Safe Haskell	None
Language	Haskell2010

Prelude

Description

This module essentially replaces the default Prelude with Universum.

It works because we are using the 'base-noprelude' package instead of base.

Synopsis

(++) :: [a] -> [a] -> [a]
seq :: a -> b -> b
filter :: (a -> Bool) -> [a] -> [a]
zip :: [a] -> [b] -> [(a, b)]
fst :: (a, b) -> a
snd :: (a, b) -> b
otherwise :: Bool
($) :: (a -> b) -> a -> b
fromIntegral :: (Integral a, Num b) => a -> b
realToFrac :: (Real a, Fractional b) => a -> b
guard :: Alternative f => Bool -> f ()
join :: Monad m => m (m a) -> m a
class Bounded a where
- minBound :: a
- maxBound :: a
class Enum a where
- succ :: a -> a
- pred :: a -> a
- toEnum :: Int -> a
- fromEnum :: a -> Int
- enumFrom :: a -> [a]
- enumFromThen :: a -> a -> [a]
- enumFromTo :: a -> a -> [a]
- enumFromThenTo :: a -> a -> a -> [a]
class Eq a where
- (==) :: a -> a -> Bool
- (/=) :: a -> a -> Bool
class Fractional a => Floating a where
- pi :: a
- exp :: a -> a
- sqrt :: a -> a
- (**) :: a -> a -> a
- logBase :: a -> a -> a
- sin :: a -> a
- cos :: a -> a
- tan :: a -> a
- asin :: a -> a
- acos :: a -> a
- atan :: a -> a
- sinh :: a -> a
- cosh :: a -> a
- tanh :: a -> a
- asinh :: a -> a
- acosh :: a -> a
- atanh :: a -> a
class Num a => Fractional a where
- (/) :: a -> a -> a
- recip :: a -> a
- fromRational :: Rational -> a
class (Real a, Enum a) => Integral a where
- quot :: a -> a -> a
- rem :: a -> a -> a
- div :: a -> a -> a
- mod :: a -> a -> a
- quotRem :: a -> a -> (a, a)
- divMod :: a -> a -> (a, a)
- toInteger :: a -> Integer
class Applicative m => Monad (m :: Type -> Type) where
- (>>=) :: m a -> (a -> m b) -> m b
- (>>) :: m a -> m b -> m b
- return :: a -> m a
class Functor (f :: Type -> Type) where
- fmap :: (a -> b) -> f a -> f b
- (<$) :: a -> f b -> f a
class Num a where
- (+) :: a -> a -> a
- (-) :: a -> a -> a
- (*) :: a -> a -> a
- negate :: a -> a
- abs :: a -> a
- signum :: a -> a
- fromInteger :: Integer -> a
class Eq a => Ord a where
- compare :: a -> a -> Ordering
- (<) :: a -> a -> Bool
- (<=) :: a -> a -> Bool
- (>) :: a -> a -> Bool
- (>=) :: a -> a -> Bool
- max :: a -> a -> a
- min :: a -> a -> a
class Read a
class (Num a, Ord a) => Real a where
- toRational :: a -> Rational
class (Real a, Fractional a) => RealFrac a where
- properFraction :: Integral b => a -> (b, a)
- truncate :: Integral b => a -> b
- round :: Integral b => a -> b
- ceiling :: Integral b => a -> b
- floor :: Integral b => a -> b
class Show a
class Typeable (a :: k)
class Monad m => MonadFail (m :: Type -> Type) where
- fail :: String -> m a
class IsString a where
- fromString :: String -> a
class Functor f => Applicative (f :: Type -> Type) where
- pure :: a -> f a
- (<*>) :: f (a -> b) -> f a -> f b
- liftA2 :: (a -> b -> c) -> f a -> f b -> f c
- (*>) :: f a -> f b -> f b
- (<*) :: f a -> f b -> f a
class Foldable (t :: Type -> Type)
class (Functor t, Foldable t) => Traversable (t :: Type -> Type) where
- traverse :: Applicative f => (a -> f b) -> t a -> f (t b)
- sequenceA :: Applicative f => t (f a) -> f (t a)
- mapM :: Monad m => (a -> m b) -> t a -> m (t b)
- sequence :: Monad m => t (m a) -> m (t a)
class Generic a
class KnownNat (n :: Nat)
class IsLabel (x :: Symbol) a where
- fromLabel :: a
class Semigroup a where
- (<>) :: a -> a -> a
- sconcat :: NonEmpty a -> a
- stimes :: Integral b => b -> a -> a
class Semigroup a => Monoid a where
- mempty :: a
- mappend :: a -> a -> a
- mconcat :: [a] -> a
data Bool
- = False
- | True
data Char
data Double = D# Double#
data Float = F# Float#
data Int
data Int8
data Int16
data Int32
data Int64
data Integer
data Natural
data Maybe a
- = Nothing
- | Just a
data Ordering
- = LT
- | EQ
- | GT
data Ratio a = !a :% !a
type Rational = Ratio Integer
data IO a
data Word
data Word8
data Word16
data Word32
data Word64
data Ptr a
data FunPtr a
data Either a b
- = Left a
- | Right b
data Constraint
type family CmpNat (a :: Nat) (b :: Nat) :: Ordering where ...
class a ~R# b => Coercible (a :: k0) (b :: k0)
data CallStack
data Handle
integralEnumFromThenTo :: Integral a => a -> a -> a -> [a]
integralEnumFromTo :: Integral a => a -> a -> [a]
integralEnumFromThen :: (Integral a, Bounded a) => a -> a -> [a]
integralEnumFrom :: (Integral a, Bounded a) => a -> [a]
gcdWord' :: Word -> Word -> Word
gcdInt' :: Int -> Int -> Int
(^^%^^) :: Integral a => Rational -> a -> Rational
(^%^) :: Integral a => Rational -> a -> Rational
numericEnumFromThenTo :: (Ord a, Fractional a) => a -> a -> a -> [a]
numericEnumFromTo :: (Ord a, Fractional a) => a -> a -> [a]
numericEnumFromThen :: Fractional a => a -> a -> [a]
numericEnumFrom :: Fractional a => a -> [a]
notANumber :: Rational
infinity :: Rational
ratioPrec1 :: Int
ratioPrec :: Int
underflowError :: a
overflowError :: a
ratioZeroDenominatorError :: a
divZeroError :: a
reduce :: Integral a => a -> a -> Ratio a
boundedEnumFromThen :: (Enum a, Bounded a) => a -> a -> [a]
boundedEnumFrom :: (Enum a, Bounded a) => a -> [a]
maxInt :: Int
minInt :: Int
newtype Compose (f :: k -> Type) (g :: k1 -> k) (a :: k1) :: forall k k1. (k -> Type) -> (k1 -> k) -> k1 -> Type = Compose {
- getCompose :: f (g a)
}
vacuous :: Functor f => f Void -> f a
absurd :: Void -> a
data Void
mtimesDefault :: (Integral b, Monoid a) => b -> a -> a
cycle1 :: Semigroup m => m -> m
data WrappedMonoid m
newtype Option a = Option {
- getOption :: Maybe a
}
sortWith :: Ord b => (a -> b) -> [a] -> [a]
class Bifunctor (p :: Type -> Type -> Type) where
- bimap :: (a -> b) -> (c -> d) -> p a c -> p b d
- first :: (a -> b) -> p a c -> p b c
- second :: (b -> c) -> p a b -> p a c
init :: NonEmpty a -> [a]
last :: NonEmpty a -> a
tail :: NonEmpty a -> [a]
head :: NonEmpty a -> a
nonEmpty :: [a] -> Maybe (NonEmpty a)
showStackTrace :: IO (Maybe String)
getStackTrace :: IO (Maybe [Location])
class Monad m => MonadIO (m :: Type -> Type) where
- liftIO :: IO a -> m a
mfilter :: MonadPlus m => (a -> Bool) -> m a -> m a
(<$!>) :: Monad m => (a -> b) -> m a -> m b
unless :: Applicative f => Bool -> f () -> f ()
replicateM_ :: Applicative m => Int -> m a -> m ()
replicateM :: Applicative m => Int -> m a -> m [a]
foldM_ :: (Foldable t, Monad m) => (b -> a -> m b) -> b -> t a -> m ()
foldM :: (Foldable t, Monad m) => (b -> a -> m b) -> b -> t a -> m b
zipWithM_ :: Applicative m => (a -> b -> m c) -> [a] -> [b] -> m ()
zipWithM :: Applicative m => (a -> b -> m c) -> [a] -> [b] -> m [c]
mapAndUnzipM :: Applicative m => (a -> m (b, c)) -> [a] -> m ([b], [c])
forever :: Applicative f => f a -> f b
(<=<) :: Monad m => (b -> m c) -> (a -> m b) -> a -> m c
(>=>) :: Monad m => (a -> m b) -> (b -> m c) -> a -> m c
filterM :: Applicative m => (a -> m Bool) -> [a] -> m [a]
foldMapDefault :: (Traversable t, Monoid m) => (a -> m) -> t a -> m
fmapDefault :: Traversable t => (a -> b) -> t a -> t b
mapAccumR :: Traversable t => (a -> b -> (a, c)) -> a -> t b -> (a, t c)
mapAccumL :: Traversable t => (a -> b -> (a, c)) -> a -> t b -> (a, t c)
forM :: (Traversable t, Monad m) => t a -> (a -> m b) -> m (t b)
optional :: Alternative f => f a -> f (Maybe a)
newtype ZipList a = ZipList {
- getZipList :: [a]
}
(&&&) :: Arrow a => a b c -> a b c' -> a b (c, c')
newtype Identity a = Identity {
- runIdentity :: a
}
stderr :: Handle
stdin :: Handle
withFrozenCallStack :: HasCallStack => (HasCallStack -> a) -> a
callStack :: HasCallStack -> CallStack
writeTVar :: TVar a -> a -> STM ()
readTVar :: TVar a -> STM a
newTVar :: a -> STM (TVar a)
data STM a
data TVar a
stdout :: Handle
data IORef a
type FilePath = String
prettyCallStack :: CallStack -> String
prettySrcLoc :: SrcLoc -> String
class (Typeable e, Show e) => Exception e where
- toException :: e -> SomeException
- fromException :: SomeException -> Maybe e
- displayException :: e -> String
newtype Const a (b :: k) :: forall k. Type -> k -> Type = Const {
- getConst :: a
}
minimumBy :: Foldable t => (a -> a -> Ordering) -> t a -> a
maximumBy :: Foldable t => (a -> a -> Ordering) -> t a -> a
concatMap :: Foldable t => (a -> [b]) -> t a -> [b]
concat :: Foldable t => t [a] -> [a]
foldlM :: (Foldable t, Monad m) => (b -> a -> m b) -> b -> t a -> m b
foldrM :: (Foldable t, Monad m) => (a -> b -> m b) -> b -> t a -> m b
newtype First a = First {
- getFirst :: Maybe a
}
newtype Last a = Last {
- getLast :: Maybe a
}
stimesMonoid :: (Integral b, Monoid a) => b -> a -> a
stimesIdempotent :: Integral b => b -> a -> a
newtype Dual a = Dual {
- getDual :: a
}
newtype Endo a = Endo {
- appEndo :: a -> a
}
newtype All = All {
- getAll :: Bool
}
newtype Any = Any {
- getAny :: Bool
}
newtype Sum a = Sum {
- getSum :: a
}
newtype Product a = Product {
- getProduct :: a
}
newtype Alt (f :: k -> Type) (a :: k) :: forall k. (k -> Type) -> k -> Type = Alt {
- getAlt :: f a
}
someNatVal :: Natural -> SomeNat
natVal :: KnownNat n => proxy n -> Natural
data SomeNat where
- SomeNat :: forall (n :: Nat). KnownNat n => Proxy n -> SomeNat
unfoldr :: (b -> Maybe (a, b)) -> b -> [a]
sortOn :: Ord b => (a -> b) -> [a] -> [a]
sortBy :: (a -> a -> Ordering) -> [a] -> [a]
sort :: Ord a => [a] -> [a]
permutations :: [a] -> [[a]]
subsequences :: [a] -> [[a]]
tails :: [a] -> [[a]]
inits :: [a] -> [[a]]
group :: Eq a => [a] -> [[a]]
genericReplicate :: Integral i => i -> a -> [a]
genericSplitAt :: Integral i => i -> [a] -> ([a], [a])
genericDrop :: Integral i => i -> [a] -> [a]
genericTake :: Integral i => i -> [a] -> [a]
genericLength :: Num i => [a] -> i
transpose :: [[a]] -> [[a]]
intercalate :: [a] -> [[a]] -> [a]
intersperse :: a -> [a] -> [a]
isPrefixOf :: Eq a => [a] -> [a] -> Bool
readMaybe :: Read a => String -> Maybe a
reads :: Read a => ReadS a
isRight :: Either a b -> Bool
isLeft :: Either a b -> Bool
partitionEithers :: [Either a b] -> ([a], [b])
rights :: [Either a b] -> [b]
lefts :: [Either a b] -> [a]
either :: (a -> c) -> (b -> c) -> Either a b -> c
comparing :: Ord a => (b -> a) -> b -> b -> Ordering
newtype Down a = Down a
data Proxy (t :: k) :: forall k. k -> Type = Proxy
data IOMode
- = ReadMode
- | WriteMode
- | AppendMode
- | ReadWriteMode
byteSwap64 :: Word64 -> Word64
byteSwap32 :: Word32 -> Word32
byteSwap16 :: Word16 -> Word16
xor :: Bits a => a -> a -> a
bool :: a -> a -> Bool -> a
(&) :: a -> (a -> b) -> b
on :: (b -> b -> c) -> (a -> b) -> a -> a -> c
fix :: (a -> a) -> a
void :: Functor f => f a -> f ()
($>) :: Functor f => f a -> b -> f b
(<&>) :: Functor f => f a -> (a -> b) -> f b
(<$>) :: Functor f => (a -> b) -> f a -> f b
lcm :: Integral a => a -> a -> a
gcd :: Integral a => a -> a -> a
(^^) :: (Fractional a, Integral b) => a -> b -> a
(^) :: (Num a, Integral b) => a -> b -> a
odd :: Integral a => a -> Bool
even :: Integral a => a -> Bool
denominator :: Ratio a -> a
numerator :: Ratio a -> a
chr :: Int -> Char
unzip3 :: [(a, b, c)] -> ([a], [b], [c])
unzip :: [(a, b)] -> ([a], [b])
zipWith :: (a -> b -> c) -> [a] -> [b] -> [c]
zip3 :: [a] -> [b] -> [c] -> [(a, b, c)]
reverse :: [a] -> [a]
break :: (a -> Bool) -> [a] -> ([a], [a])
splitAt :: Int -> [a] -> ([a], [a])
drop :: Int -> [a] -> [a]
take :: Int -> [a] -> [a]
dropWhile :: (a -> Bool) -> [a] -> [a]
takeWhile :: (a -> Bool) -> [a] -> [a]
cycle :: [a] -> [a]
replicate :: Int -> a -> [a]
repeat :: a -> [a]
iterate :: (a -> a) -> a -> [a]
scanr :: (a -> b -> b) -> b -> [a] -> [b]
scanl :: (b -> a -> b) -> b -> [a] -> [b]
mapMaybe :: (a -> Maybe b) -> [a] -> [b]
catMaybes :: [Maybe a] -> [a]
listToMaybe :: [a] -> Maybe a
maybeToList :: Maybe a -> [a]
fromMaybe :: a -> Maybe a -> a
isNothing :: Maybe a -> Bool
isJust :: Maybe a -> Bool
maybe :: b -> (a -> b) -> Maybe a -> b
swap :: (a, b) -> (b, a)
uncurry :: (a -> b -> c) -> (a, b) -> c
curry :: ((a, b) -> c) -> a -> b -> c
data MVar a
subtract :: Num a => a -> a -> a
currentCallStack :: IO [String]
asTypeOf :: a -> a -> a
flip :: (a -> b -> c) -> b -> a -> c
(.) :: (b -> c) -> (a -> b) -> a -> c
const :: a -> b -> a
id :: a -> a
ord :: Char -> Int
ap :: Monad m => m (a -> b) -> m a -> m b
liftM5 :: Monad m => (a1 -> a2 -> a3 -> a4 -> a5 -> r) -> m a1 -> m a2 -> m a3 -> m a4 -> m a5 -> m r
liftM4 :: Monad m => (a1 -> a2 -> a3 -> a4 -> r) -> m a1 -> m a2 -> m a3 -> m a4 -> m r
liftM3 :: Monad m => (a1 -> a2 -> a3 -> r) -> m a1 -> m a2 -> m a3 -> m r
liftM2 :: Monad m => (a1 -> a2 -> r) -> m a1 -> m a2 -> m r
when :: Applicative f => Bool -> f () -> f ()
(=<<) :: Monad m => (a -> m b) -> m a -> m b
liftA3 :: Applicative f => (a -> b -> c -> d) -> f a -> f b -> f c -> f d
(<**>) :: Applicative f => f a -> f (a -> b) -> f b
class Applicative f => Alternative (f :: Type -> Type) where
- empty :: f a
- (<|>) :: f a -> f a -> f a
- some :: f a -> f [a]
- many :: f a -> f [a]
class (Alternative m, Monad m) => MonadPlus (m :: Type -> Type) where
- mzero :: m a
- mplus :: m a -> m a -> m a
data NonEmpty a = a :| [a]
type String = [Char]
getCallStack :: CallStack -> [([Char], SrcLoc)]
type HasCallStack = ?callStack :: CallStack
stimesIdempotentMonoid :: (Integral b, Monoid a) => b -> a -> a
data SomeException where
- SomeException :: forall e. Exception e => e -> SomeException
(&&) :: Bool -> Bool -> Bool
(||) :: Bool -> Bool -> Bool
not :: Bool -> Bool
data ByteString
data IntMap a
data IntSet
data Map k a
data Seq a
data Set a
force :: NFData a => a -> a
($!!) :: NFData a => (a -> b) -> a -> b
deepseq :: NFData a => a -> b -> b
class NFData a where
- rnf :: a -> ()
newtype MaybeT (m :: Type -> Type) a = MaybeT {
- runMaybeT :: m (Maybe a)
}
newtype ExceptT e (m :: Type -> Type) a = ExceptT (m (Either e a))
class Monad m => MonadThrow (m :: Type -> Type)
class MonadThrow m => MonadCatch (m :: Type -> Type)
class MonadCatch m => MonadMask (m :: Type -> Type) where
- mask :: ((forall a. m a -> m a) -> m b) -> m b
- uninterruptibleMask :: ((forall a. m a -> m a) -> m b) -> m b
- generalBracket :: m a -> (a -> ExitCase b -> m c) -> (a -> m b) -> m (b, c)
class Hashable a where
- hashWithSalt :: Int -> a -> Int
(^?) :: s -> Getting (First a) s a -> Maybe a
(^..) :: s -> Getting (Endo [a]) s a -> [a]
(^.) :: s -> Getting a s a -> a
set :: ASetter s t a b -> b -> s -> t
(.~) :: ASetter s t a b -> b -> s -> t
over :: ASetter s t a b -> (a -> b) -> s -> t
(%~) :: ASetter s t a b -> (a -> b) -> s -> t
_1 :: Field1 s t a b => Lens s t a b
_2 :: Field2 s t a b => Lens s t a b
_3 :: Field3 s t a b => Lens s t a b
_4 :: Field4 s t a b => Lens s t a b
_5 :: Field5 s t a b => Lens s t a b
type Lens s t a b = forall (f :: Type -> Type). Functor f => (a -> f b) -> s -> f t
type Lens' s a = Lens s s a a
type Traversal s t a b = forall (f :: Type -> Type). Applicative f => (a -> f b) -> s -> f t
type Traversal' s a = Traversal s s a a
modify :: MonadState s m => (s -> s) -> m ()
gets :: MonadState s m => (s -> a) -> m a
asks :: MonadReader r m => (r -> a) -> m a
class Monad m => MonadReader r (m :: Type -> Type) | m -> r where
- ask :: m r
- local :: (r -> r) -> m a -> m a
- reader :: (r -> a) -> m a
class Monad m => MonadState s (m :: Type -> Type) | m -> s where
- get :: m s
- put :: s -> m ()
- state :: (s -> (a, s)) -> m a
newtype ReaderT r (m :: k -> Type) (a :: k) :: forall k. Type -> (k -> Type) -> k -> Type = ReaderT {
- runReaderT :: r -> m a
}
type Reader r = ReaderT r Identity
preuse :: MonadState s m => Getting (First a) s a -> m (Maybe a)
use :: MonadState s m => Getting a s a -> m a
preview :: MonadReader s m => Getting (First a) s a -> m (Maybe a)
view :: MonadReader s m => Getting a s a -> m a
class MonadTrans (t :: (Type -> Type) -> Type -> Type) where
- lift :: Monad m => m a -> t m a
data IdentityT (f :: k -> Type) (a :: k) :: forall k. (k -> Type) -> k -> Type
modify' :: MonadState s m => (s -> s) -> m ()
runExceptT :: ExceptT e m a -> m (Either e a)
runReader :: Reader r a -> r -> a
newtype StateT s (m :: Type -> Type) a = StateT {
- runStateT :: s -> m (a, s)
}
type State s = StateT s Identity
runState :: State s a -> s -> (a, s)
evalState :: State s a -> s -> a
execState :: State s a -> s -> s
withState :: (s -> s) -> State s a -> State s a
evalStateT :: Monad m => StateT s m a -> s -> m a
execStateT :: Monad m => StateT s m a -> s -> m s
bracketOnError :: MonadMask m => m a -> (a -> m b) -> (a -> m c) -> m c
finally :: MonadMask m => m a -> m b -> m a
bracket_ :: MonadMask m => m a -> m b -> m c -> m c
bracket :: MonadMask m => m a -> (a -> m b) -> (a -> m c) -> m c
onException :: MonadMask m => m a -> m b -> m a
tryAny :: MonadCatch m => m a -> m (Either SomeException a)
try :: (MonadCatch m, Exception e) => m a -> m (Either e a)
handleAny :: MonadCatch m => (SomeException -> m a) -> m a -> m a
catchAny :: MonadCatch m => m a -> (SomeException -> m a) -> m a
catch :: (MonadCatch m, Exception e) => m a -> (e -> m a) -> m a
throwM :: (MonadThrow m, Exception e) => e -> m a
modifyTVar' :: TVar a -> (a -> a) -> STM ()
fromStrict :: Text -> Text
toStrict :: Text -> Text
unwords :: [Text] -> Text
unlines :: [Text] -> Text
lines :: Text -> [Text]
words :: Text -> [Text]
decodeUtf8' :: ByteString -> Either UnicodeException Text
decodeUtf8With :: OnDecodeError -> ByteString -> Text
data Text
lenientDecode :: OnDecodeError
strictDecode :: OnDecodeError
type OnError a b = String -> Maybe a -> Maybe b
type OnDecodeError = OnError Word8 Char
data UnicodeException
exceptToMaybeT :: Functor m => ExceptT e m a -> MaybeT m a
maybeToExceptT :: Functor m => e -> MaybeT m a -> ExceptT e m a
class SuperComposition a b c | a b -> c where
- (...) :: a -> b -> c
type ($) (f :: k -> k1) (a :: k) = f a
type family Each (c :: [k -> Constraint]) (as :: [k]) :: Constraint where ...
type With (a :: [k -> Constraint]) (b :: k) = a <+> b
show :: (Show a, IsString b) => a -> b
readEither :: (ToString a, Read b) => a -> Either Text b
type LText = Text
type LByteString = ByteString
class ConvertUtf8 a b where
- encodeUtf8 :: a -> b
- decodeUtf8 :: b -> a
- decodeUtf8Strict :: b -> Either UnicodeException a
class ToText a where
- toText :: a -> Text
class ToLText a where
- toLText :: a -> Text
class ToString a where
- toString :: a -> String
undefined :: HasCallStack => a
traceId :: Text -> Text
traceM :: Monad m => Text -> m ()
traceShowM :: (Show a, Monad m) => a -> m ()
traceShowIdWith :: Show s => (a -> s) -> a -> a
traceIdWith :: (a -> Text) -> a -> a
traceShowId :: Show a => a -> a
traceShow :: Show a => a -> b -> b
error :: HasCallStack => Text -> a
trace :: Text -> a -> a
data Undefined = Undefined
putLTextLn :: MonadIO m => Text -> m ()
putLText :: MonadIO m => Text -> m ()
putTextLn :: MonadIO m => Text -> m ()
putText :: MonadIO m => Text -> m ()
hPrint :: (MonadIO m, Show a) => Handle -> a -> m ()
print :: (MonadIO m, Show a) => a -> m ()
putStrLn :: (Print a, MonadIO m) => a -> m ()
putStr :: (Print a, MonadIO m) => a -> m ()
hPutStrLn :: (Print a, MonadIO m) => Handle -> a -> m ()
hPutStr :: (Print a, MonadIO m) => Handle -> a -> m ()
class Print a
unstableNub :: (Eq a, Hashable a) => [a] -> [a]
sortNub :: Ord a => [a] -> [a]
hashNub :: (Eq a, Hashable a) => [a] -> [a]
ordNub :: Ord a => [a] -> [a]
guardM :: MonadPlus m => m Bool -> m ()
ifM :: Monad m => m Bool -> m a -> m a -> m a
unlessM :: Monad m => m Bool -> m () -> m ()
whenM :: Monad m => m Bool -> m () -> m ()
evaluateNF_ :: (NFData a, MonadIO m) => a -> m ()
evaluateNF :: (NFData a, MonadIO m) => a -> m a
evaluateWHNF_ :: MonadIO m => a -> m ()
evaluateWHNF :: MonadIO m => a -> m a
note :: MonadError e m => e -> Maybe a -> m a
bug :: (HasCallStack, Exception e) => e -> a
pattern Exc :: forall e. Exception e => e -> SomeException
data Bug = Bug SomeException CallStack
whenNotNullM :: Monad m => m [a] -> (NonEmpty a -> m ()) -> m ()
whenNotNull :: Applicative f => [a] -> (NonEmpty a -> f ()) -> f ()
uncons :: [a] -> Maybe (a, [a])
anyM :: (Container f, Monad m) => (Element f -> m Bool) -> f -> m Bool
allM :: (Container f, Monad m) => (Element f -> m Bool) -> f -> m Bool
orM :: (Container f, Element f ~ m Bool, Monad m) => f -> m Bool
andM :: (Container f, Element f ~ m Bool, Monad m) => f -> m Bool
concatForM :: (Applicative f, Monoid m, Container (l m), Element (l m) ~ m, Traversable l) => l a -> (a -> f m) -> f m
concatMapM :: (Applicative f, Monoid m, Container (l m), Element (l m) ~ m, Traversable l) => (a -> f m) -> l a -> f m
asum :: (Container t, Alternative f, Element t ~ f a) => t -> f a
sequence_ :: (Container t, Monad m, Element t ~ m a) => t -> m ()
sequenceA_ :: (Container t, Applicative f, Element t ~ f a) => t -> f ()
forM_ :: (Container t, Monad m) => t -> (Element t -> m b) -> m ()
mapM_ :: (Container t, Monad m) => (Element t -> m b) -> t -> m ()
for_ :: (Container t, Applicative f) => t -> (Element t -> f b) -> f ()
traverse_ :: (Container t, Applicative f) => (Element t -> f b) -> t -> f ()
product :: (Container t, Num (Element t)) => t -> Element t
sum :: (Container t, Num (Element t)) => t -> Element t
flipfoldl' :: (Container t, Element t ~ a) => (a -> b -> b) -> b -> t -> b
class ToPairs t where
- toPairs :: t -> [(Key t, Val t)]
- keys :: t -> [Key t]
- elems :: t -> [Val t]
class Container t where
- type Element t :: Type
- toList :: t -> [Element t]
- null :: t -> Bool
- foldr :: (Element t -> b -> b) -> b -> t -> b
- foldl :: (b -> Element t -> b) -> b -> t -> b
- foldl' :: (b -> Element t -> b) -> b -> t -> b
- length :: t -> Int
- elem :: Element t -> t -> Bool
- maximum :: t -> Element t
- minimum :: t -> Element t
- foldMap :: Monoid m => (Element t -> m) -> t -> m
- fold :: t -> Element t
- foldr' :: (Element t -> b -> b) -> b -> t -> b
- foldr1 :: (Element t -> Element t -> Element t) -> t -> Element t
- foldl1 :: (Element t -> Element t -> Element t) -> t -> Element t
- notElem :: Element t -> t -> Bool
- all :: (Element t -> Bool) -> t -> Bool
- any :: (Element t -> Bool) -> t -> Bool
- and :: t -> Bool
- or :: t -> Bool
- find :: (Element t -> Bool) -> t -> Maybe (Element t)
- safeHead :: t -> Maybe (Element t)
class One x where
- type OneItem x :: Type
- one :: OneItem x -> x
maybeToMonoid :: Monoid m => Maybe m -> m
executingState :: s -> State s a -> s
executingStateT :: Functor f => s -> StateT s f a -> f s
evaluatingState :: s -> State s a -> a
evaluatingStateT :: Functor f => s -> StateT s f a -> f a
usingState :: s -> State s a -> (a, s)
usingStateT :: s -> StateT s m a -> m (a, s)
usingReader :: r -> Reader r a -> a
usingReaderT :: r -> ReaderT r m a -> m a
whenRightM :: Monad m => m (Either l r) -> (r -> m ()) -> m ()
whenRight :: Applicative f => Either l r -> (r -> f ()) -> f ()
whenLeftM :: Monad m => m (Either l r) -> (l -> m ()) -> m ()
whenLeft :: Applicative f => Either l r -> (l -> f ()) -> f ()
maybeToLeft :: r -> Maybe l -> Either l r
maybeToRight :: l -> Maybe r -> Either l r
rightToMaybe :: Either l r -> Maybe r
leftToMaybe :: Either l r -> Maybe l
fromRight :: b -> Either a b -> b
fromLeft :: a -> Either a b -> a
whenNothingM_ :: Monad m => m (Maybe a) -> m () -> m ()
whenNothingM :: Monad m => m (Maybe a) -> m a -> m a
whenNothing_ :: Applicative f => Maybe a -> f () -> f ()
whenNothing :: Applicative f => Maybe a -> f a -> f a
whenJustM :: Monad m => m (Maybe a) -> (a -> m ()) -> m ()
whenJust :: Applicative f => Maybe a -> (a -> f ()) -> f ()
(?:) :: Maybe a -> a -> a
atomicWriteIORef :: MonadIO m => IORef a -> a -> m ()
atomicModifyIORef' :: MonadIO m => IORef a -> (a -> (a, b)) -> m b
atomicModifyIORef :: MonadIO m => IORef a -> (a -> (a, b)) -> m b
modifyIORef' :: MonadIO m => IORef a -> (a -> a) -> m ()
modifyIORef :: MonadIO m => IORef a -> (a -> a) -> m ()
writeIORef :: MonadIO m => IORef a -> a -> m ()
readIORef :: MonadIO m => IORef a -> m a
newIORef :: MonadIO m => a -> m (IORef a)
withFile :: (MonadIO m, MonadMask m) => FilePath -> IOMode -> (Handle -> m a) -> m a
hClose :: MonadIO m => Handle -> m ()
openFile :: MonadIO m => FilePath -> IOMode -> m Handle
getLine :: MonadIO m => m Text
appendFile :: MonadIO m => FilePath -> Text -> m ()
die :: MonadIO m => String -> m a
exitSuccess :: MonadIO m => m a
exitFailure :: MonadIO m => m a
exitWith :: MonadIO m => ExitCode -> m a
readTVarIO :: MonadIO m => TVar a -> m a
newTVarIO :: MonadIO m => a -> m (TVar a)
atomically :: MonadIO m => STM a -> m a
tryTakeMVar :: MonadIO m => MVar a -> m (Maybe a)
tryReadMVar :: MonadIO m => MVar a -> m (Maybe a)
tryPutMVar :: MonadIO m => MVar a -> a -> m Bool
takeMVar :: MonadIO m => MVar a -> m a
swapMVar :: MonadIO m => MVar a -> a -> m a
readMVar :: MonadIO m => MVar a -> m a
putMVar :: MonadIO m => MVar a -> a -> m ()
newMVar :: MonadIO m => a -> m (MVar a)
newEmptyMVar :: MonadIO m => m (MVar a)
(<<$>>) :: (Functor f, Functor g) => (a -> b) -> f (g a) -> f (g b)
map :: Functor f => (a -> b) -> f a -> f b
($!) :: (a -> b) -> a -> b
pass :: Applicative f => f ()
data Vector a
data HashMap k v
data HashSet a

Documentation

(++) :: [a] -> [a] -> [a] infixr 5 #

Append two lists, i.e.,

[x1, ..., xm] ++ [y1, ..., yn] == [x1, ..., xm, y1, ..., yn]
[x1, ..., xm] ++ [y1, ...] == [x1, ..., xm, y1, ...]

If the first list is not finite, the result is the first list.

seq :: a -> b -> b #

The value of seq a b is bottom if a is bottom, and otherwise equal to b. In other words, it evaluates the first argument a to weak head normal form (WHNF). seq is usually introduced to improve performance by avoiding unneeded laziness.

A note on evaluation order: the expression seq a b does not guarantee that a will be evaluated before b. The only guarantee given by seq is that the both a and b will be evaluated before seq returns a value. In particular, this means that b may be evaluated before a. If you need to guarantee a specific order of evaluation, you must use the function pseq from the "parallel" package.

filter :: (a -> Bool) -> [a] -> [a] #

filter, applied to a predicate and a list, returns the list of those elements that satisfy the predicate; i.e.,

filter p xs = [ x | x <- xs, p x]

zip :: [a] -> [b] -> [(a, b)] #

zip takes two lists and returns a list of corresponding pairs.

zip [1, 2] ['a', 'b'] = [(1, 'a'), (2, 'b')]

If one input list is short, excess elements of the longer list are discarded:

zip [1] ['a', 'b'] = [(1, 'a')]
zip [1, 2] ['a'] = [(1, 'a')]

zip is right-lazy:

zip [] _|_ = []
zip _|_ [] = _|_

fst :: (a, b) -> a #

Extract the first component of a pair.

snd :: (a, b) -> b #

Extract the second component of a pair.

otherwise :: Bool #

otherwise is defined as the value True. It helps to make guards more readable. eg.

 f x | x < 0     = ...
     | otherwise = ...

($) :: (a -> b) -> a -> b infixr 0 #

Application operator. This operator is redundant, since ordinary application (f x) means the same as (f $ x). However, $ has low, right-associative binding precedence, so it sometimes allows parentheses to be omitted; for example:

f $ g $ h x  =  f (g (h x))

It is also useful in higher-order situations, such as map ($ 0) xs, or zipWith ($) fs xs.

Note that ($) is levity-polymorphic in its result type, so that foo $ True where foo :: Bool -> Int# is well-typed

fromIntegral :: (Integral a, Num b) => a -> b #

general coercion from integral types

realToFrac :: (Real a, Fractional b) => a -> b #

general coercion to fractional types

guard :: Alternative f => Bool -> f () #

Conditional failure of Alternative computations. Defined by

guard True  = pure ()
guard False = empty

Examples

Expand

Common uses of guard include conditionally signaling an error in an error monad and conditionally rejecting the current choice in an Alternative-based parser.

As an example of signaling an error in the error monad Maybe, consider a safe division function safeDiv x y that returns Nothing when the denominator y is zero and Just (x `div` y) otherwise. For example:

>>> safeDiv 4 0
Nothing
>>> safeDiv 4 2
Just 2

A definition of safeDiv using guards, but not guard:

safeDiv :: Int -> Int -> Maybe Int
safeDiv x y | y /= 0    = Just (x `div` y)
            | otherwise = Nothing

A definition of safeDiv using guard and Monad do-notation:

safeDiv :: Int -> Int -> Maybe Int
safeDiv x y = do
  guard (y /= 0)
  return (x `div` y)

join :: Monad m => m (m a) -> m a #

The join function is the conventional monad join operator. It is used to remove one level of monadic structure, projecting its bound argument into the outer level.

Examples

Expand

A common use of join is to run an IO computation returned from an STM transaction, since STM transactions can't perform IO directly. Recall that

atomically :: STM a -> IO a

is used to run STM transactions atomically. So, by specializing the types of atomically and join to

atomically :: STM (IO b) -> IO (IO b)
join       :: IO (IO b)  -> IO b

we can compose them as

join . atomically :: STM (IO b) -> IO b

to run an STM transaction and the IO action it returns.

class Bounded a where #

The Bounded class is used to name the upper and lower limits of a type. Ord is not a superclass of Bounded since types that are not totally ordered may also have upper and lower bounds.

The Bounded class may be derived for any enumeration type; minBound is the first constructor listed in the data declaration and maxBound is the last. Bounded may also be derived for single-constructor datatypes whose constituent types are in Bounded.

Methods

minBound :: a #

maxBound :: a #

Instances

Bounded Bool	Since: base-2.1
Instance details Defined in GHC.Enum Methods minBound :: Bool # maxBound :: Bool #
Bounded Char	Since: base-2.1
Instance details Defined in GHC.Enum Methods minBound :: Char # maxBound :: Char #
Bounded Int	Since: base-2.1
Instance details Defined in GHC.Enum Methods minBound :: Int # maxBound :: Int #
Bounded Int8	Since: base-2.1
Instance details Defined in GHC.Int Methods minBound :: Int8 # maxBound :: Int8 #
Bounded Int16	Since: base-2.1
Instance details Defined in GHC.Int Methods minBound :: Int16 # maxBound :: Int16 #
Bounded Int32	Since: base-2.1
Instance details Defined in GHC.Int Methods minBound :: Int32 # maxBound :: Int32 #
Bounded Int64	Since: base-2.1
Instance details Defined in GHC.Int Methods minBound :: Int64 # maxBound :: Int64 #
Bounded Ordering	Since: base-2.1
Instance details Defined in GHC.Enum Methods minBound :: Ordering # maxBound :: Ordering #
Bounded Word	Since: base-2.1
Instance details Defined in GHC.Enum Methods minBound :: Word # maxBound :: Word #
Bounded Word8	Since: base-2.1
Instance details Defined in GHC.Word Methods minBound :: Word8 # maxBound :: Word8 #
Bounded Word16	Since: base-2.1
Instance details Defined in GHC.Word Methods minBound :: Word16 # maxBound :: Word16 #
Bounded Word32	Since: base-2.1
Instance details Defined in GHC.Word Methods minBound :: Word32 # maxBound :: Word32 #
Bounded Word64	Since: base-2.1
Instance details Defined in GHC.Word Methods minBound :: Word64 # maxBound :: Word64 #
Bounded VecCount	Since: base-4.10.0.0
Instance details Defined in GHC.Enum Methods minBound :: VecCount # maxBound :: VecCount #
Bounded VecElem	Since: base-4.10.0.0
Instance details Defined in GHC.Enum Methods minBound :: VecElem # maxBound :: VecElem #
Bounded ()	Since: base-2.1
Instance details Defined in GHC.Enum Methods minBound :: () # maxBound :: () #
Bounded All	Since: base-2.1
Instance details Defined in Data.Semigroup.Internal Methods minBound :: All # maxBound :: All #
Bounded Any	Since: base-2.1
Instance details Defined in Data.Semigroup.Internal Methods minBound :: Any # maxBound :: Any #
Bounded Associativity	Since: base-4.9.0.0
Instance details Defined in GHC.Generics Methods minBound :: Associativity # maxBound :: Associativity #
Bounded SourceUnpackedness	Since: base-4.9.0.0
Instance details Defined in GHC.Generics Methods minBound :: SourceUnpackedness # maxBound :: SourceUnpackedness #
Bounded SourceStrictness	Since: base-4.9.0.0
Instance details Defined in GHC.Generics Methods minBound :: SourceStrictness # maxBound :: SourceStrictness #
Bounded DecidedStrictness	Since: base-4.9.0.0
Instance details Defined in GHC.Generics Methods minBound :: DecidedStrictness # maxBound :: DecidedStrictness #
Bounded Undefined
Instance details Defined in Universum.Debug Methods minBound :: Undefined # maxBound :: Undefined #
Bounded a => Bounded (Min a)	Since: base-4.9.0.0
Instance details Defined in Data.Semigroup Methods minBound :: Min a # maxBound :: Min a #
Bounded a => Bounded (Max a)	Since: base-4.9.0.0
Instance details Defined in Data.Semigroup Methods minBound :: Max a # maxBound :: Max a #
Bounded a => Bounded (First a)	Since: base-4.9.0.0
Instance details Defined in Data.Semigroup Methods minBound :: First a # maxBound :: First a #
Bounded a => Bounded (Last a)	Since: base-4.9.0.0
Instance details Defined in Data.Semigroup Methods minBound :: Last a # maxBound :: Last a #
Bounded m => Bounded (WrappedMonoid m)	Since: base-4.9.0.0
Instance details Defined in Data.Semigroup Methods minBound :: WrappedMonoid m # maxBound :: WrappedMonoid m #
Bounded a => Bounded (Identity a)	Since: base-4.9.0.0
Instance details Defined in Data.Functor.Identity Methods minBound :: Identity a # maxBound :: Identity a #
Bounded a => Bounded (Dual a)	Since: base-2.1
Instance details Defined in Data.Semigroup.Internal Methods minBound :: Dual a # maxBound :: Dual a #
Bounded a => Bounded (Sum a)	Since: base-2.1
Instance details Defined in Data.Semigroup.Internal Methods minBound :: Sum a # maxBound :: Sum a #
Bounded a => Bounded (Product a)	Since: base-2.1
Instance details Defined in Data.Semigroup.Internal Methods minBound :: Product a # maxBound :: Product a #
(Bounded a, Bounded b) => Bounded (a, b)	Since: base-2.1
Instance details Defined in GHC.Enum Methods minBound :: (a, b) # maxBound :: (a, b) #
Bounded (Proxy t)	Since: base-4.7.0.0
Instance details Defined in Data.Proxy Methods minBound :: Proxy t # maxBound :: Proxy t #
(Bounded a, Bounded b, Bounded c) => Bounded (a, b, c)	Since: base-2.1
Instance details Defined in GHC.Enum Methods minBound :: (a, b, c) # maxBound :: (a, b, c) #
Bounded a => Bounded (Const a b)	Since: base-4.9.0.0
Instance details Defined in Data.Functor.Const Methods minBound :: Const a b # maxBound :: Const a b #
(Applicative f, Bounded a) => Bounded (Ap f a)	Since: base-4.12.0.0
Instance details Defined in Data.Monoid Methods minBound :: Ap f a # maxBound :: Ap f a #
a ~ b => Bounded (a :~: b)	Since: base-4.7.0.0
Instance details Defined in Data.Type.Equality Methods minBound :: a :~: b # maxBound :: a :~: b #
(Bounded a, Bounded b, Bounded c, Bounded d) => Bounded (a, b, c, d)	Since: base-2.1
Instance details Defined in GHC.Enum Methods minBound :: (a, b, c, d) # maxBound :: (a, b, c, d) #
a ~~ b => Bounded (a :~~: b)	Since: base-4.10.0.0
Instance details Defined in Data.Type.Equality Methods minBound :: a :~~: b # maxBound :: a :~~: b #
(Bounded a, Bounded b, Bounded c, Bounded d, Bounded e) => Bounded (a, b, c, d, e)	Since: base-2.1
Instance details Defined in GHC.Enum Methods minBound :: (a, b, c, d, e) # maxBound :: (a, b, c, d, e) #
(Bounded a, Bounded b, Bounded c, Bounded d, Bounded e, Bounded f) => Bounded (a, b, c, d, e, f)	Since: base-2.1
Instance details Defined in GHC.Enum Methods minBound :: (a, b, c, d, e, f) # maxBound :: (a, b, c, d, e, f) #
(Bounded a, Bounded b, Bounded c, Bounded d, Bounded e, Bounded f, Bounded g) => Bounded (a, b, c, d, e, f, g)	Since: base-2.1
Instance details Defined in GHC.Enum Methods minBound :: (a, b, c, d, e, f, g) # maxBound :: (a, b, c, d, e, f, g) #
(Bounded a, Bounded b, Bounded c, Bounded d, Bounded e, Bounded f, Bounded g, Bounded h) => Bounded (a, b, c, d, e, f, g, h)	Since: base-2.1
Instance details Defined in GHC.Enum Methods minBound :: (a, b, c, d, e, f, g, h) # maxBound :: (a, b, c, d, e, f, g, h) #
(Bounded a, Bounded b, Bounded c, Bounded d, Bounded e, Bounded f, Bounded g, Bounded h, Bounded i) => Bounded (a, b, c, d, e, f, g, h, i)	Since: base-2.1
Instance details Defined in GHC.Enum Methods minBound :: (a, b, c, d, e, f, g, h, i) # maxBound :: (a, b, c, d, e, f, g, h, i) #
(Bounded a, Bounded b, Bounded c, Bounded d, Bounded e, Bounded f, Bounded g, Bounded h, Bounded i, Bounded j) => Bounded (a, b, c, d, e, f, g, h, i, j)	Since: base-2.1
Instance details Defined in GHC.Enum Methods minBound :: (a, b, c, d, e, f, g, h, i, j) # maxBound :: (a, b, c, d, e, f, g, h, i, j) #
(Bounded a, Bounded b, Bounded c, Bounded d, Bounded e, Bounded f, Bounded g, Bounded h, Bounded i, Bounded j, Bounded k) => Bounded (a, b, c, d, e, f, g, h, i, j, k)	Since: base-2.1
Instance details Defined in GHC.Enum Methods minBound :: (a, b, c, d, e, f, g, h, i, j, k) # maxBound :: (a, b, c, d, e, f, g, h, i, j, k) #
(Bounded a, Bounded b, Bounded c, Bounded d, Bounded e, Bounded f, Bounded g, Bounded h, Bounded i, Bounded j, Bounded k, Bounded l) => Bounded (a, b, c, d, e, f, g, h, i, j, k, l)	Since: base-2.1
Instance details Defined in GHC.Enum Methods minBound :: (a, b, c, d, e, f, g, h, i, j, k, l) # maxBound :: (a, b, c, d, e, f, g, h, i, j, k, l) #
(Bounded a, Bounded b, Bounded c, Bounded d, Bounded e, Bounded f, Bounded g, Bounded h, Bounded i, Bounded j, Bounded k, Bounded l, Bounded m) => Bounded (a, b, c, d, e, f, g, h, i, j, k, l, m)	Since: base-2.1
Instance details Defined in GHC.Enum Methods minBound :: (a, b, c, d, e, f, g, h, i, j, k, l, m) # maxBound :: (a, b, c, d, e, f, g, h, i, j, k, l, m) #
(Bounded a, Bounded b, Bounded c, Bounded d, Bounded e, Bounded f, Bounded g, Bounded h, Bounded i, Bounded j, Bounded k, Bounded l, Bounded m, Bounded n) => Bounded (a, b, c, d, e, f, g, h, i, j, k, l, m, n)	Since: base-2.1
Instance details Defined in GHC.Enum Methods minBound :: (a, b, c, d, e, f, g, h, i, j, k, l, m, n) # maxBound :: (a, b, c, d, e, f, g, h, i, j, k, l, m, n) #
(Bounded a, Bounded b, Bounded c, Bounded d, Bounded e, Bounded f, Bounded g, Bounded h, Bounded i, Bounded j, Bounded k, Bounded l, Bounded m, Bounded n, Bounded o) => Bounded (a, b, c, d, e, f, g, h, i, j, k, l, m, n, o)	Since: base-2.1
Instance details Defined in GHC.Enum Methods minBound :: (a, b, c, d, e, f, g, h, i, j, k, l, m, n, o) # maxBound :: (a, b, c, d, e, f, g, h, i, j, k, l, m, n, o) #

class Enum a where #

Class Enum defines operations on sequentially ordered types.

The enumFrom... methods are used in Haskell's translation of arithmetic sequences.

Instances of Enum may be derived for any enumeration type (types whose constructors have no fields). The nullary constructors are assumed to be numbered left-to-right by fromEnum from 0 through n-1. See Chapter 10 of the Haskell Report for more details.

For any type that is an instance of class Bounded as well as Enum, the following should hold:

The calls succ maxBound and pred minBound should result in a runtime error.
fromEnum and toEnum should give a runtime error if the result value is not representable in the result type. For example, toEnum 7 :: Bool is an error.
enumFrom and enumFromThen should be defined with an implicit bound, thus:

   enumFrom     x   = enumFromTo     x maxBound
   enumFromThen x y = enumFromThenTo x y bound
     where
       bound | fromEnum y >= fromEnum x = maxBound
             | otherwise                = minBound

Minimal complete definition

toEnum, fromEnum

Methods

succ :: a -> a #

the successor of a value. For numeric types, succ adds 1.

pred :: a -> a #

the predecessor of a value. For numeric types, pred subtracts 1.

toEnum :: Int -> a #

Convert from an Int.

fromEnum :: a -> Int #

Convert to an Int. It is implementation-dependent what fromEnum returns when applied to a value that is too large to fit in an Int.

enumFrom :: a -> [a] #

Used in Haskell's translation of [n..] with [n..] = enumFrom n, a possible implementation being enumFrom n = n : enumFrom (succ n). For example:

```
enumFrom 4 :: [Integer] = [4,5,6,7,...]
```

enumFrom 6 :: [Int] = [6,7,8,9,...,maxBound :: Int]

enumFromThen :: a -> a -> [a] #

Used in Haskell's translation of [n,n'..] with [n,n'..] = enumFromThen n n', a possible implementation being enumFromThen n n' = n : n' : worker (f x) (f x n'), worker s v = v : worker s (s v), x = fromEnum n' - fromEnum n and f n y | n > 0 = f (n - 1) (succ y) | n < 0 = f (n + 1) (pred y) | otherwise = y For example:

enumFromThen 4 6 :: [Integer] = [4,6,8,10...]

enumFromThen 6 2 :: [Int] = [6,2,-2,-6,...,minBound :: Int]

enumFromTo :: a -> a -> [a] #

Used in Haskell's translation of [n..m] with [n..m] = enumFromTo n m, a possible implementation being enumFromTo n m | n <= m = n : enumFromTo (succ n) m | otherwise = []. For example:

```
enumFromTo 6 10 :: [Int] = [6,7,8,9,10]
```
```
enumFromTo 42 1 :: [Integer] = []
```

enumFromThenTo :: a -> a -> a -> [a] #

Used in Haskell's translation of [n,n'..m] with [n,n'..m] = enumFromThenTo n n' m, a possible implementation being enumFromThenTo n n' m = worker (f x) (c x) n m, x = fromEnum n' - fromEnum n, c x = bool (>=) ((x 0) f n y | n > 0 = f (n - 1) (succ y) | n < 0 = f (n + 1) (pred y) | otherwise = y and worker s c v m | c v m = v : worker s c (s v) m | otherwise = [] For example:

enumFromThenTo 4 2 -6 :: [Integer] = [4,2,0,-2,-4,-6]

```
enumFromThenTo 6 8 2 :: [Int] = []
```

Instances

Enum Bool	Since: base-2.1
Instance details Defined in GHC.Enum Methods succ :: Bool -> Bool # pred :: Bool -> Bool # toEnum :: Int -> Bool # fromEnum :: Bool -> Int # enumFrom :: Bool -> [Bool] # enumFromThen :: Bool -> Bool -> [Bool] # enumFromTo :: Bool -> Bool -> [Bool] # enumFromThenTo :: Bool -> Bool -> Bool -> [Bool] #
Enum Char	Since: base-2.1
Instance details Defined in GHC.Enum Methods succ :: Char -> Char # pred :: Char -> Char # toEnum :: Int -> Char # fromEnum :: Char -> Int # enumFrom :: Char -> [Char] # enumFromThen :: Char -> Char -> [Char] # enumFromTo :: Char -> Char -> [Char] # enumFromThenTo :: Char -> Char -> Char -> [Char] #
Enum Int	Since: base-2.1
Instance details Defined in GHC.Enum Methods succ :: Int -> Int # pred :: Int -> Int # toEnum :: Int -> Int # fromEnum :: Int -> Int # enumFrom :: Int -> [Int] # enumFromThen :: Int -> Int -> [Int] # enumFromTo :: Int -> Int -> [Int] # enumFromThenTo :: Int -> Int -> Int -> [Int] #
Enum Int8	Since: base-2.1
Instance details Defined in GHC.Int Methods succ :: Int8 -> Int8 # pred :: Int8 -> Int8 # toEnum :: Int -> Int8 # fromEnum :: Int8 -> Int # enumFrom :: Int8 -> [Int8] # enumFromThen :: Int8 -> Int8 -> [Int8] # enumFromTo :: Int8 -> Int8 -> [Int8] # enumFromThenTo :: Int8 -> Int8 -> Int8 -> [Int8] #
Enum Int16	Since: base-2.1
Instance details Defined in GHC.Int Methods succ :: Int16 -> Int16 # pred :: Int16 -> Int16 # toEnum :: Int -> Int16 # fromEnum :: Int16 -> Int # enumFrom :: Int16 -> [Int16] # enumFromThen :: Int16 -> Int16 -> [Int16] # enumFromTo :: Int16 -> Int16 -> [Int16] # enumFromThenTo :: Int16 -> Int16 -> Int16 -> [Int16] #
Enum Int32	Since: base-2.1
Instance details Defined in GHC.Int Methods succ :: Int32 -> Int32 # pred :: Int32 -> Int32 # toEnum :: Int -> Int32 # fromEnum :: Int32 -> Int # enumFrom :: Int32 -> [Int32] # enumFromThen :: Int32 -> Int32 -> [Int32] # enumFromTo :: Int32 -> Int32 -> [Int32] # enumFromThenTo :: Int32 -> Int32 -> Int32 -> [Int32] #
Enum Int64	Since: base-2.1
Instance details Defined in GHC.Int Methods succ :: Int64 -> Int64 # pred :: Int64 -> Int64 # toEnum :: Int -> Int64 # fromEnum :: Int64 -> Int # enumFrom :: Int64 -> [Int64] # enumFromThen :: Int64 -> Int64 -> [Int64] # enumFromTo :: Int64 -> Int64 -> [Int64] # enumFromThenTo :: Int64 -> Int64 -> Int64 -> [Int64] #
Enum Integer	Since: base-2.1
Instance details Defined in GHC.Enum Methods succ :: Integer -> Integer # pred :: Integer -> Integer # toEnum :: Int -> Integer # fromEnum :: Integer -> Int # enumFrom :: Integer -> [Integer] # enumFromThen :: Integer -> Integer -> [Integer] # enumFromTo :: Integer -> Integer -> [Integer] # enumFromThenTo :: Integer -> Integer -> Integer -> [Integer] #
Enum Natural	Since: base-4.8.0.0
Instance details Defined in GHC.Enum Methods succ :: Natural -> Natural # pred :: Natural -> Natural # toEnum :: Int -> Natural # fromEnum :: Natural -> Int # enumFrom :: Natural -> [Natural] # enumFromThen :: Natural -> Natural -> [Natural] # enumFromTo :: Natural -> Natural -> [Natural] # enumFromThenTo :: Natural -> Natural -> Natural -> [Natural] #
Enum Ordering	Since: base-2.1
Instance details Defined in GHC.Enum Methods succ :: Ordering -> Ordering # pred :: Ordering -> Ordering # toEnum :: Int -> Ordering # fromEnum :: Ordering -> Int # enumFrom :: Ordering -> [Ordering] # enumFromThen :: Ordering -> Ordering -> [Ordering] # enumFromTo :: Ordering -> Ordering -> [Ordering] # enumFromThenTo :: Ordering -> Ordering -> Ordering -> [Ordering] #
Enum Word	Since: base-2.1
Instance details Defined in GHC.Enum Methods succ :: Word -> Word # pred :: Word -> Word # toEnum :: Int -> Word # fromEnum :: Word -> Int # enumFrom :: Word -> [Word] # enumFromThen :: Word -> Word -> [Word] # enumFromTo :: Word -> Word -> [Word] # enumFromThenTo :: Word -> Word -> Word -> [Word] #
Enum Word8	Since: base-2.1
Instance details Defined in GHC.Word Methods succ :: Word8 -> Word8 # pred :: Word8 -> Word8 # toEnum :: Int -> Word8 # fromEnum :: Word8 -> Int # enumFrom :: Word8 -> [Word8] # enumFromThen :: Word8 -> Word8 -> [Word8] # enumFromTo :: Word8 -> Word8 -> [Word8] # enumFromThenTo :: Word8 -> Word8 -> Word8 -> [Word8] #
Enum Word16	Since: base-2.1
Instance details Defined in GHC.Word Methods succ :: Word16 -> Word16 # pred :: Word16 -> Word16 # toEnum :: Int -> Word16 # fromEnum :: Word16 -> Int # enumFrom :: Word16 -> [Word16] # enumFromThen :: Word16 -> Word16 -> [Word16] # enumFromTo :: Word16 -> Word16 -> [Word16] # enumFromThenTo :: Word16 -> Word16 -> Word16 -> [Word16] #
Enum Word32	Since: base-2.1
Instance details Defined in GHC.Word Methods succ :: Word32 -> Word32 # pred :: Word32 -> Word32 # toEnum :: Int -> Word32 # fromEnum :: Word32 -> Int # enumFrom :: Word32 -> [Word32] # enumFromThen :: Word32 -> Word32 -> [Word32] # enumFromTo :: Word32 -> Word32 -> [Word32] # enumFromThenTo :: Word32 -> Word32 -> Word32 -> [Word32] #
Enum Word64	Since: base-2.1
Instance details Defined in GHC.Word Methods succ :: Word64 -> Word64 # pred :: Word64 -> Word64 # toEnum :: Int -> Word64 # fromEnum :: Word64 -> Int # enumFrom :: Word64 -> [Word64] # enumFromThen :: Word64 -> Word64 -> [Word64] # enumFromTo :: Word64 -> Word64 -> [Word64] # enumFromThenTo :: Word64 -> Word64 -> Word64 -> [Word64] #
Enum VecCount	Since: base-4.10.0.0
Instance details Defined in GHC.Enum Methods succ :: VecCount -> VecCount # pred :: VecCount -> VecCount # toEnum :: Int -> VecCount # fromEnum :: VecCount -> Int # enumFrom :: VecCount -> [VecCount] # enumFromThen :: VecCount -> VecCount -> [VecCount] # enumFromTo :: VecCount -> VecCount -> [VecCount] # enumFromThenTo :: VecCount -> VecCount -> VecCount -> [VecCount] #
Enum VecElem	Since: base-4.10.0.0
Instance details Defined in GHC.Enum Methods succ :: VecElem -> VecElem # pred :: VecElem -> VecElem # toEnum :: Int -> VecElem # fromEnum :: VecElem -> Int # enumFrom :: VecElem -> [VecElem] # enumFromThen :: VecElem -> VecElem -> [VecElem] # enumFromTo :: VecElem -> VecElem -> [VecElem] # enumFromThenTo :: VecElem -> VecElem -> VecElem -> [VecElem] #
Enum ()	Since: base-2.1
Instance details Defined in GHC.Enum Methods succ :: () -> () # pred :: () -> () # toEnum :: Int -> () # fromEnum :: () -> Int # enumFrom :: () -> [()] # enumFromThen :: () -> () -> [()] # enumFromTo :: () -> () -> [()] # enumFromThenTo :: () -> () -> () -> [()] #
Enum Associativity	Since: base-4.9.0.0
Instance details Defined in GHC.Generics Methods succ :: Associativity -> Associativity # pred :: Associativity -> Associativity # toEnum :: Int -> Associativity # fromEnum :: Associativity -> Int # enumFrom :: Associativity -> [Associativity] # enumFromThen :: Associativity -> Associativity -> [Associativity] # enumFromTo :: Associativity -> Associativity -> [Associativity] # enumFromThenTo :: Associativity -> Associativity -> Associativity -> [Associativity] #
Enum SourceUnpackedness	Since: base-4.9.0.0
Instance details Defined in GHC.Generics Methods succ :: SourceUnpackedness -> SourceUnpackedness # pred :: SourceUnpackedness -> SourceUnpackedness # toEnum :: Int -> SourceUnpackedness # fromEnum :: SourceUnpackedness -> Int # enumFrom :: SourceUnpackedness -> [SourceUnpackedness] # enumFromThen :: SourceUnpackedness -> SourceUnpackedness -> [SourceUnpackedness] # enumFromTo :: SourceUnpackedness -> SourceUnpackedness -> [SourceUnpackedness] # enumFromThenTo :: SourceUnpackedness -> SourceUnpackedness -> SourceUnpackedness -> [SourceUnpackedness] #
Enum SourceStrictness	Since: base-4.9.0.0
Instance details Defined in GHC.Generics Methods succ :: SourceStrictness -> SourceStrictness # pred :: SourceStrictness -> SourceStrictness # toEnum :: Int -> SourceStrictness # fromEnum :: SourceStrictness -> Int # enumFrom :: SourceStrictness -> [SourceStrictness] # enumFromThen :: SourceStrictness -> SourceStrictness -> [SourceStrictness] # enumFromTo :: SourceStrictness -> SourceStrictness -> [SourceStrictness] # enumFromThenTo :: SourceStrictness -> SourceStrictness -> SourceStrictness -> [SourceStrictness] #
Enum DecidedStrictness	Since: base-4.9.0.0
Instance details Defined in GHC.Generics Methods succ :: DecidedStrictness -> DecidedStrictness # pred :: DecidedStrictness -> DecidedStrictness # toEnum :: Int -> DecidedStrictness # fromEnum :: DecidedStrictness -> Int # enumFrom :: DecidedStrictness -> [DecidedStrictness] # enumFromThen :: DecidedStrictness -> DecidedStrictness -> [DecidedStrictness] # enumFromTo :: DecidedStrictness -> DecidedStrictness -> [DecidedStrictness] # enumFromThenTo :: DecidedStrictness -> DecidedStrictness -> DecidedStrictness -> [DecidedStrictness] #
Enum IOMode	Since: base-4.2.0.0
Instance details Defined in GHC.IO.IOMode Methods succ :: IOMode -> IOMode # pred :: IOMode -> IOMode # toEnum :: Int -> IOMode # fromEnum :: IOMode -> Int # enumFrom :: IOMode -> [IOMode] # enumFromThen :: IOMode -> IOMode -> [IOMode] # enumFromTo :: IOMode -> IOMode -> [IOMode] # enumFromThenTo :: IOMode -> IOMode -> IOMode -> [IOMode] #
Enum Undefined
Instance details Defined in Universum.Debug Methods succ :: Undefined -> Undefined # pred :: Undefined -> Undefined # toEnum :: Int -> Undefined # fromEnum :: Undefined -> Int # enumFrom :: Undefined -> [Undefined] # enumFromThen :: Undefined -> Undefined -> [Undefined] # enumFromTo :: Undefined -> Undefined -> [Undefined] # enumFromThenTo :: Undefined -> Undefined -> Undefined -> [Undefined] #
Integral a => Enum (Ratio a)	Since: base-2.0.1
Instance details Defined in GHC.Real Methods succ :: Ratio a -> Ratio a # pred :: Ratio a -> Ratio a # toEnum :: Int -> Ratio a # fromEnum :: Ratio a -> Int # enumFrom :: Ratio a -> [Ratio a] # enumFromThen :: Ratio a -> Ratio a -> [Ratio a] # enumFromTo :: Ratio a -> Ratio a -> [Ratio a] # enumFromThenTo :: Ratio a -> Ratio a -> Ratio a -> [Ratio a] #
Enum a => Enum (Min a)	Since: base-4.9.0.0
Instance details Defined in Data.Semigroup Methods succ :: Min a -> Min a # pred :: Min a -> Min a # toEnum :: Int -> Min a # fromEnum :: Min a -> Int # enumFrom :: Min a -> [Min a] # enumFromThen :: Min a -> Min a -> [Min a] # enumFromTo :: Min a -> Min a -> [Min a] # enumFromThenTo :: Min a -> Min a -> Min a -> [Min a] #
Enum a => Enum (Max a)	Since: base-4.9.0.0
Instance details Defined in Data.Semigroup Methods succ :: Max a -> Max a # pred :: Max a -> Max a # toEnum :: Int -> Max a # fromEnum :: Max a -> Int # enumFrom :: Max a -> [Max a] # enumFromThen :: Max a -> Max a -> [Max a] # enumFromTo :: Max a -> Max a -> [Max a] # enumFromThenTo :: Max a -> Max a -> Max a -> [Max a] #
Enum a => Enum (First a)	Since: base-4.9.0.0
Instance details Defined in Data.Semigroup Methods succ :: First a -> First a # pred :: First a -> First a # toEnum :: Int -> First a # fromEnum :: First a -> Int # enumFrom :: First a -> [First a] # enumFromThen :: First a -> First a -> [First a] # enumFromTo :: First a -> First a -> [First a] # enumFromThenTo :: First a -> First a -> First a -> [First a] #
Enum a => Enum (Last a)	Since: base-4.9.0.0
Instance details Defined in Data.Semigroup Methods succ :: Last a -> Last a # pred :: Last a -> Last a # toEnum :: Int -> Last a # fromEnum :: Last a -> Int # enumFrom :: Last a -> [Last a] # enumFromThen :: Last a -> Last a -> [Last a] # enumFromTo :: Last a -> Last a -> [Last a] # enumFromThenTo :: Last a -> Last a -> Last a -> [Last a] #
Enum a => Enum (WrappedMonoid a)	Since: base-4.9.0.0
Instance details Defined in Data.Semigroup Methods succ :: WrappedMonoid a -> WrappedMonoid a # pred :: WrappedMonoid a -> WrappedMonoid a # toEnum :: Int -> WrappedMonoid a # fromEnum :: WrappedMonoid a -> Int # enumFrom :: WrappedMonoid a -> [WrappedMonoid a] # enumFromThen :: WrappedMonoid a -> WrappedMonoid a -> [WrappedMonoid a] # enumFromTo :: WrappedMonoid a -> WrappedMonoid a -> [WrappedMonoid a] # enumFromThenTo :: WrappedMonoid a -> WrappedMonoid a -> WrappedMonoid a -> [WrappedMonoid a] #
Enum a => Enum (Identity a)	Since: base-4.9.0.0
Instance details Defined in Data.Functor.Identity Methods succ :: Identity a -> Identity a # pred :: Identity a -> Identity a # toEnum :: Int -> Identity a # fromEnum :: Identity a -> Int # enumFrom :: Identity a -> [Identity a] # enumFromThen :: Identity a -> Identity a -> [Identity a] # enumFromTo :: Identity a -> Identity a -> [Identity a] # enumFromThenTo :: Identity a -> Identity a -> Identity a -> [Identity a] #
Enum (Proxy s)	Since: base-4.7.0.0
Instance details Defined in Data.Proxy Methods succ :: Proxy s -> Proxy s # pred :: Proxy s -> Proxy s # toEnum :: Int -> Proxy s # fromEnum :: Proxy s -> Int # enumFrom :: Proxy s -> [Proxy s] # enumFromThen :: Proxy s -> Proxy s -> [Proxy s] # enumFromTo :: Proxy s -> Proxy s -> [Proxy s] # enumFromThenTo :: Proxy s -> Proxy s -> Proxy s -> [Proxy s] #
Enum a => Enum (Const a b)	Since: base-4.9.0.0
Instance details Defined in Data.Functor.Const Methods succ :: Const a b -> Const a b # pred :: Const a b -> Const a b # toEnum :: Int -> Const a b # fromEnum :: Const a b -> Int # enumFrom :: Const a b -> [Const a b] # enumFromThen :: Const a b -> Const a b -> [Const a b] # enumFromTo :: Const a b -> Const a b -> [Const a b] # enumFromThenTo :: Const a b -> Const a b -> Const a b -> [Const a b] #
Enum (f a) => Enum (Ap f a)	Since: base-4.12.0.0
Instance details Defined in Data.Monoid Methods succ :: Ap f a -> Ap f a # pred :: Ap f a -> Ap f a # toEnum :: Int -> Ap f a # fromEnum :: Ap f a -> Int # enumFrom :: Ap f a -> [Ap f a] # enumFromThen :: Ap f a -> Ap f a -> [Ap f a] # enumFromTo :: Ap f a -> Ap f a -> [Ap f a] # enumFromThenTo :: Ap f a -> Ap f a -> Ap f a -> [Ap f a] #
Enum (f a) => Enum (Alt f a)	Since: base-4.8.0.0
Instance details Defined in Data.Semigroup.Internal Methods succ :: Alt f a -> Alt f a # pred :: Alt f a -> Alt f a # toEnum :: Int -> Alt f a # fromEnum :: Alt f a -> Int # enumFrom :: Alt f a -> [Alt f a] # enumFromThen :: Alt f a -> Alt f a -> [Alt f a] # enumFromTo :: Alt f a -> Alt f a -> [Alt f a] # enumFromThenTo :: Alt f a -> Alt f a -> Alt f a -> [Alt f a] #
a ~ b => Enum (a :~: b)	Since: base-4.7.0.0
Instance details Defined in Data.Type.Equality Methods succ :: (a :~: b) -> a :~: b # pred :: (a :~: b) -> a :~: b # toEnum :: Int -> a :~: b # fromEnum :: (a :~: b) -> Int # enumFrom :: (a :~: b) -> [a :~: b] # enumFromThen :: (a :~: b) -> (a :~: b) -> [a :~: b] # enumFromTo :: (a :~: b) -> (a :~: b) -> [a :~: b] # enumFromThenTo :: (a :~: b) -> (a :~: b) -> (a :~: b) -> [a :~: b] #
a ~~ b => Enum (a :~~: b)	Since: base-4.10.0.0
Instance details Defined in Data.Type.Equality Methods succ :: (a :~~: b) -> a :~~: b # pred :: (a :~~: b) -> a :~~: b # toEnum :: Int -> a :~~: b # fromEnum :: (a :~~: b) -> Int # enumFrom :: (a :~~: b) -> [a :~~: b] # enumFromThen :: (a :~~: b) -> (a :~~: b) -> [a :~~: b] # enumFromTo :: (a :~~: b) -> (a :~~: b) -> [a :~~: b] # enumFromThenTo :: (a :~~: b) -> (a :~~: b) -> (a :~~: b) -> [a :~~: b] #

class Eq a where #

The Eq class defines equality (==) and inequality (/=). All the basic datatypes exported by the Prelude are instances of Eq, and Eq may be derived for any datatype whose constituents are also instances of Eq.

The Haskell Report defines no laws for Eq. However, == is customarily expected to implement an equivalence relationship where two values comparing equal are indistinguishable by "public" functions, with a "public" function being one not allowing to see implementation details. For example, for a type representing non-normalised natural numbers modulo 100, a "public" function doesn't make the difference between 1 and 201. It is expected to have the following properties:

Reflexivity: x == x = True
Symmetry: x == y = y == x
Transitivity: if x == y && y == z = True, then x == z = True
Substitutivity: if x == y = True and f is a "public" function whose return type is an instance of Eq, then f x == f y = True
Negation: x /= y = not (x == y)

Minimal complete definition: either == or /=.

Minimal complete definition

(==) | (/=)

Methods

(==) :: a -> a -> Bool infix 4 #

(/=) :: a -> a -> Bool infix 4 #

Instances

Eq Bool
Instance details Defined in GHC.Classes Methods (==) :: Bool -> Bool -> Bool # (/=) :: Bool -> Bool -> Bool #
Eq Char
Instance details Defined in GHC.Classes Methods (==) :: Char -> Char -> Bool # (/=) :: Char -> Char -> Bool #
Eq Double	Note that due to the presence of `NaN`, `Double`'s `Eq` instance does not satisfy reflexivity. `>>>` `0/0 == (0/0 :: Double)`False Also note that `Double`'s `Eq` instance does not satisfy substitutivity: `>>>` `0 == (-0 :: Double)`True `>>>` `recip 0 == recip (-0 :: Double)`False
Instance details Defined in GHC.Classes Methods (==) :: Double -> Double -> Bool # (/=) :: Double -> Double -> Bool #
Eq Float	Note that due to the presence of `NaN`, `Float`'s `Eq` instance does not satisfy reflexivity. `>>>` `0/0 == (0/0 :: Float)`False Also note that `Float`'s `Eq` instance does not satisfy substitutivity: `>>>` `0 == (-0 :: Float)`True `>>>` `recip 0 == recip (-0 :: Float)`False
Instance details Defined in GHC.Classes Methods (==) :: Float -> Float -> Bool # (/=) :: Float -> Float -> Bool #
Eq Int
Instance details Defined in GHC.Classes Methods (==) :: Int -> Int -> Bool # (/=) :: Int -> Int -> Bool #
Eq Int8	Since: base-2.1
Instance details Defined in GHC.Int Methods (==) :: Int8 -> Int8 -> Bool # (/=) :: Int8 -> Int8 -> Bool #
Eq Int16	Since: base-2.1
Instance details Defined in GHC.Int Methods (==) :: Int16 -> Int16 -> Bool # (/=) :: Int16 -> Int16 -> Bool #
Eq Int32	Since: base-2.1
Instance details Defined in GHC.Int Methods (==) :: Int32 -> Int32 -> Bool # (/=) :: Int32 -> Int32 -> Bool #
Eq Int64	Since: base-2.1
Instance details Defined in GHC.Int Methods (==) :: Int64 -> Int64 -> Bool # (/=) :: Int64 -> Int64 -> Bool #
Eq Integer
Instance details Defined in GHC.Integer.Type Methods (==) :: Integer -> Integer -> Bool # (/=) :: Integer -> Integer -> Bool #
Eq Natural	Since: base-4.8.0.0
Instance details Defined in GHC.Natural Methods (==) :: Natural -> Natural -> Bool # (/=) :: Natural -> Natural -> Bool #
Eq Ordering
Instance details Defined in GHC.Classes Methods (==) :: Ordering -> Ordering -> Bool # (/=) :: Ordering -> Ordering -> Bool #
Eq Word
Instance details Defined in GHC.Classes Methods (==) :: Word -> Word -> Bool # (/=) :: Word -> Word -> Bool #
Eq Word8	Since: base-2.1
Instance details Defined in GHC.Word Methods (==) :: Word8 -> Word8 -> Bool # (/=) :: Word8 -> Word8 -> Bool #
Eq Word16	Since: base-2.1
Instance details Defined in GHC.Word Methods (==) :: Word16 -> Word16 -> Bool # (/=) :: Word16 -> Word16 -> Bool #
Eq Word32	Since: base-2.1
Instance details Defined in GHC.Word Methods (==) :: Word32 -> Word32 -> Bool # (/=) :: Word32 -> Word32 -> Bool #
Eq Word64	Since: base-2.1
Instance details Defined in GHC.Word Methods (==) :: Word64 -> Word64 -> Bool # (/=) :: Word64 -> Word64 -> Bool #
Eq SomeTypeRep
Instance details Defined in Data.Typeable.Internal Methods (==) :: SomeTypeRep -> SomeTypeRep -> Bool # (/=) :: SomeTypeRep -> SomeTypeRep -> Bool #
Eq ()
Instance details Defined in GHC.Classes Methods (==) :: () -> () -> Bool # (/=) :: () -> () -> Bool #
Eq TyCon
Instance details Defined in GHC.Classes Methods (==) :: TyCon -> TyCon -> Bool # (/=) :: TyCon -> TyCon -> Bool #
Eq Module
Instance details Defined in GHC.Classes Methods (==) :: Module -> Module -> Bool # (/=) :: Module -> Module -> Bool #
Eq TrName
Instance details Defined in GHC.Classes Methods (==) :: TrName -> TrName -> Bool # (/=) :: TrName -> TrName -> Bool #
Eq Handle	Since: base-4.1.0.0
Instance details Defined in GHC.IO.Handle.Types Methods (==) :: Handle -> Handle -> Bool # (/=) :: Handle -> Handle -> Bool #
Eq BigNat
Instance details Defined in GHC.Integer.Type Methods (==) :: BigNat -> BigNat -> Bool # (/=) :: BigNat -> BigNat -> Bool #
Eq Void	Since: base-4.8.0.0
Instance details Defined in Data.Void Methods (==) :: Void -> Void -> Bool # (/=) :: Void -> Void -> Bool #
Eq SpecConstrAnnotation	Since: base-4.3.0.0
Instance details Defined in GHC.Exts Methods (==) :: SpecConstrAnnotation -> SpecConstrAnnotation -> Bool # (/=) :: SpecConstrAnnotation -> SpecConstrAnnotation -> Bool #
Eq Version	Since: base-2.1
Instance details Defined in Data.Version Methods (==) :: Version -> Version -> Bool # (/=) :: Version -> Version -> Bool #
Eq ThreadId	Since: base-4.2.0.0
Instance details Defined in GHC.Conc.Sync Methods (==) :: ThreadId -> ThreadId -> Bool # (/=) :: ThreadId -> ThreadId -> Bool #
Eq BlockReason	Since: base-4.3.0.0
Instance details Defined in GHC.Conc.Sync Methods (==) :: BlockReason -> BlockReason -> Bool # (/=) :: BlockReason -> BlockReason -> Bool #
Eq ThreadStatus	Since: base-4.3.0.0
Instance details Defined in GHC.Conc.Sync Methods (==) :: ThreadStatus -> ThreadStatus -> Bool # (/=) :: ThreadStatus -> ThreadStatus -> Bool #
Eq AsyncException	Since: base-4.2.0.0
Instance details Defined in GHC.IO.Exception Methods (==) :: AsyncException -> AsyncException -> Bool # (/=) :: AsyncException -> AsyncException -> Bool #
Eq ArrayException	Since: base-4.2.0.0
Instance details Defined in GHC.IO.Exception Methods (==) :: ArrayException -> ArrayException -> Bool # (/=) :: ArrayException -> ArrayException -> Bool #
Eq ExitCode
Instance details Defined in GHC.IO.Exception Methods (==) :: ExitCode -> ExitCode -> Bool # (/=) :: ExitCode -> ExitCode -> Bool #
Eq IOErrorType	Since: base-4.1.0.0
Instance details Defined in GHC.IO.Exception Methods (==) :: IOErrorType -> IOErrorType -> Bool # (/=) :: IOErrorType -> IOErrorType -> Bool #
Eq BufferMode	Since: base-4.2.0.0
Instance details Defined in GHC.IO.Handle.Types Methods (==) :: BufferMode -> BufferMode -> Bool # (/=) :: BufferMode -> BufferMode -> Bool #
Eq Newline	Since: base-4.2.0.0
Instance details Defined in GHC.IO.Handle.Types Methods (==) :: Newline -> Newline -> Bool # (/=) :: Newline -> Newline -> Bool #
Eq NewlineMode	Since: base-4.2.0.0
Instance details Defined in GHC.IO.Handle.Types Methods (==) :: NewlineMode -> NewlineMode -> Bool # (/=) :: NewlineMode -> NewlineMode -> Bool #
Eq MaskingState	Since: base-4.3.0.0
Instance details Defined in GHC.IO Methods (==) :: MaskingState -> MaskingState -> Bool # (/=) :: MaskingState -> MaskingState -> Bool #
Eq IOException	Since: base-4.1.0.0
Instance details Defined in GHC.IO.Exception Methods (==) :: IOException -> IOException -> Bool # (/=) :: IOException -> IOException -> Bool #
Eq ErrorCall	Since: base-4.7.0.0
Instance details Defined in GHC.Exception Methods (==) :: ErrorCall -> ErrorCall -> Bool # (/=) :: ErrorCall -> ErrorCall -> Bool #
Eq ArithException	Since: base-3.0
Instance details Defined in GHC.Exception.Type Methods (==) :: ArithException -> ArithException -> Bool # (/=) :: ArithException -> ArithException -> Bool #
Eq All	Since: base-2.1
Instance details Defined in Data.Semigroup.Internal Methods (==) :: All -> All -> Bool # (/=) :: All -> All -> Bool #
Eq Any	Since: base-2.1
Instance details Defined in Data.Semigroup.Internal Methods (==) :: Any -> Any -> Bool # (/=) :: Any -> Any -> Bool #
Eq Fixity	Since: base-4.6.0.0
Instance details Defined in GHC.Generics Methods (==) :: Fixity -> Fixity -> Bool # (/=) :: Fixity -> Fixity -> Bool #
Eq Associativity	Since: base-4.6.0.0
Instance details Defined in GHC.Generics Methods (==) :: Associativity -> Associativity -> Bool # (/=) :: Associativity -> Associativity -> Bool #
Eq SourceUnpackedness	Since: base-4.9.0.0
Instance details Defined in GHC.Generics Methods (==) :: SourceUnpackedness -> SourceUnpackedness -> Bool # (/=) :: SourceUnpackedness -> SourceUnpackedness -> Bool #
Eq SourceStrictness	Since: base-4.9.0.0
Instance details Defined in GHC.Generics Methods (==) :: SourceStrictness -> SourceStrictness -> Bool # (/=) :: SourceStrictness -> SourceStrictness -> Bool #
Eq DecidedStrictness	Since: base-4.9.0.0
Instance details Defined in GHC.Generics Methods (==) :: DecidedStrictness -> DecidedStrictness -> Bool # (/=) :: DecidedStrictness -> DecidedStrictness -> Bool #
Eq SomeNat	Since: base-4.7.0.0
Instance details Defined in GHC.TypeNats Methods (==) :: SomeNat -> SomeNat -> Bool # (/=) :: SomeNat -> SomeNat -> Bool #
Eq IOMode	Since: base-4.2.0.0
Instance details Defined in GHC.IO.IOMode Methods (==) :: IOMode -> IOMode -> Bool # (/=) :: IOMode -> IOMode -> Bool #
Eq SrcLoc	Since: base-4.9.0.0
Instance details Defined in GHC.Stack.Types Methods (==) :: SrcLoc -> SrcLoc -> Bool # (/=) :: SrcLoc -> SrcLoc -> Bool #
Eq ByteString
Instance details Defined in Data.ByteString.Internal Methods (==) :: ByteString -> ByteString -> Bool # (/=) :: ByteString -> ByteString -> Bool #
Eq IntSet
Instance details Defined in Data.IntSet.Internal Methods (==) :: IntSet -> IntSet -> Bool # (/=) :: IntSet -> IntSet -> Bool #
Eq UnicodeException
Instance details Defined in Data.Text.Encoding.Error Methods (==) :: UnicodeException -> UnicodeException -> Bool # (/=) :: UnicodeException -> UnicodeException -> Bool #
Eq Undefined
Instance details Defined in Universum.Debug Methods (==) :: Undefined -> Undefined -> Bool # (/=) :: Undefined -> Undefined -> Bool #
Eq CodePoint
Instance details Defined in Data.Text.Encoding Methods (==) :: CodePoint -> CodePoint -> Bool # (/=) :: CodePoint -> CodePoint -> Bool #
Eq DecoderState
Instance details Defined in Data.Text.Encoding Methods (==) :: DecoderState -> DecoderState -> Bool # (/=) :: DecoderState -> DecoderState -> Bool #
Eq a => Eq [a]
Instance details Defined in GHC.Classes Methods (==) :: [a] -> [a] -> Bool # (/=) :: [a] -> [a] -> Bool #
Eq a => Eq (Maybe a)	Since: base-2.1
Instance details Defined in GHC.Maybe Methods (==) :: Maybe a -> Maybe a -> Bool # (/=) :: Maybe a -> Maybe a -> Bool #
Eq a => Eq (Ratio a)	Since: base-2.1
Instance details Defined in GHC.Real Methods (==) :: Ratio a -> Ratio a -> Bool # (/=) :: Ratio a -> Ratio a -> Bool #
Eq (Ptr a)	Since: base-2.1
Instance details Defined in GHC.Ptr Methods (==) :: Ptr a -> Ptr a -> Bool # (/=) :: Ptr a -> Ptr a -> Bool #
Eq (FunPtr a)
Instance details Defined in GHC.Ptr Methods (==) :: FunPtr a -> FunPtr a -> Bool # (/=) :: FunPtr a -> FunPtr a -> Bool #
Eq p => Eq (Par1 p)	Since: base-4.7.0.0
Instance details Defined in GHC.Generics Methods (==) :: Par1 p -> Par1 p -> Bool # (/=) :: Par1 p -> Par1 p -> Bool #
Eq a => Eq (Min a)	Since: base-4.9.0.0
Instance details Defined in Data.Semigroup Methods (==) :: Min a -> Min a -> Bool # (/=) :: Min a -> Min a -> Bool #
Eq a => Eq (Max a)	Since: base-4.9.0.0
Instance details Defined in Data.Semigroup Methods (==) :: Max a -> Max a -> Bool # (/=) :: Max a -> Max a -> Bool #
Eq a => Eq (First a)	Since: base-4.9.0.0
Instance details Defined in Data.Semigroup Methods (==) :: First a -> First a -> Bool # (/=) :: First a -> First a -> Bool #
Eq a => Eq (Last a)	Since: base-4.9.0.0
Instance details Defined in Data.Semigroup Methods (==) :: Last a -> Last a -> Bool # (/=) :: Last a -> Last a -> Bool #
Eq m => Eq (WrappedMonoid m)	Since: base-4.9.0.0
Instance details Defined in Data.Semigroup Methods (==) :: WrappedMonoid m -> WrappedMonoid m -> Bool # (/=) :: WrappedMonoid m -> WrappedMonoid m -> Bool #
Eq a => Eq (Option a)	Since: base-4.9.0.0
Instance details Defined in Data.Semigroup Methods (==) :: Option a -> Option a -> Bool # (/=) :: Option a -> Option a -> Bool #
Eq a => Eq (ZipList a)	Since: base-4.7.0.0
Instance details Defined in Control.Applicative Methods (==) :: ZipList a -> ZipList a -> Bool # (/=) :: ZipList a -> ZipList a -> Bool #
Eq a => Eq (Identity a)	Since: base-4.8.0.0
Instance details Defined in Data.Functor.Identity Methods (==) :: Identity a -> Identity a -> Bool # (/=) :: Identity a -> Identity a -> Bool #
Eq (TVar a)	Since: base-4.8.0.0
Instance details Defined in GHC.Conc.Sync Methods (==) :: TVar a -> TVar a -> Bool # (/=) :: TVar a -> TVar a -> Bool #
Eq (IORef a)	^ Pointer equality. Since: base-4.1.0.0
Instance details Defined in GHC.IORef Methods (==) :: IORef a -> IORef a -> Bool # (/=) :: IORef a -> IORef a -> Bool #
Eq a => Eq (First a)	Since: base-2.1
Instance details Defined in Data.Monoid Methods (==) :: First a -> First a -> Bool # (/=) :: First a -> First a -> Bool #
Eq a => Eq (Last a)	Since: base-2.1
Instance details Defined in Data.Monoid Methods (==) :: Last a -> Last a -> Bool # (/=) :: Last a -> Last a -> Bool #
Eq a => Eq (Dual a)	Since: base-2.1
Instance details Defined in Data.Semigroup.Internal Methods (==) :: Dual a -> Dual a -> Bool # (/=) :: Dual a -> Dual a -> Bool #
Eq a => Eq (Sum a)	Since: base-2.1
Instance details Defined in Data.Semigroup.Internal Methods (==) :: Sum a -> Sum a -> Bool # (/=) :: Sum a -> Sum a -> Bool #
Eq a => Eq (Product a)	Since: base-2.1
Instance details Defined in Data.Semigroup.Internal Methods (==) :: Product a -> Product a -> Bool # (/=) :: Product a -> Product a -> Bool #
Eq a => Eq (Down a)	Since: base-4.6.0.0
Instance details Defined in Data.Ord Methods (==) :: Down a -> Down a -> Bool # (/=) :: Down a -> Down a -> Bool #
Eq (MVar a)	Since: base-4.1.0.0
Instance details Defined in GHC.MVar Methods (==) :: MVar a -> MVar a -> Bool # (/=) :: MVar a -> MVar a -> Bool #
Eq a => Eq (NonEmpty a)	Since: base-4.9.0.0
Instance details Defined in GHC.Base Methods (==) :: NonEmpty a -> NonEmpty a -> Bool # (/=) :: NonEmpty a -> NonEmpty a -> Bool #
Eq a => Eq (IntMap a)
Instance details Defined in Data.IntMap.Internal Methods (==) :: IntMap a -> IntMap a -> Bool # (/=) :: IntMap a -> IntMap a -> Bool #
Eq a => Eq (Seq a)
Instance details Defined in Data.Sequence.Internal Methods (==) :: Seq a -> Seq a -> Bool # (/=) :: Seq a -> Seq a -> Bool #
Eq a => Eq (ViewL a)
Instance details Defined in Data.Sequence.Internal Methods (==) :: ViewL a -> ViewL a -> Bool # (/=) :: ViewL a -> ViewL a -> Bool #
Eq a => Eq (ViewR a)
Instance details Defined in Data.Sequence.Internal Methods (==) :: ViewR a -> ViewR a -> Bool # (/=) :: ViewR a -> ViewR a -> Bool #
Eq a => Eq (Set a)
Instance details Defined in Data.Set.Internal Methods (==) :: Set a -> Set a -> Bool # (/=) :: Set a -> Set a -> Bool #
Eq a => Eq (Hashed a)	Uses precomputed hash to detect inequality faster
Instance details Defined in Data.Hashable.Class Methods (==) :: Hashed a -> Hashed a -> Bool # (/=) :: Hashed a -> Hashed a -> Bool #
Eq a => Eq (Vector a)
Instance details Defined in Data.Vector Methods (==) :: Vector a -> Vector a -> Bool # (/=) :: Vector a -> Vector a -> Bool #
Eq a => Eq (HashSet a)
Instance details Defined in Data.HashSet.Base Methods (==) :: HashSet a -> HashSet a -> Bool # (/=) :: HashSet a -> HashSet a -> Bool #
(Eq a, Eq b) => Eq (Either a b)	Since: base-2.1
Instance details Defined in Data.Either Methods (==) :: Either a b -> Either a b -> Bool # (/=) :: Either a b -> Either a b -> Bool #
Eq (V1 p)	Since: base-4.9.0.0
Instance details Defined in GHC.Generics Methods (==) :: V1 p -> V1 p -> Bool # (/=) :: V1 p -> V1 p -> Bool #
Eq (U1 p)	Since: base-4.9.0.0
Instance details Defined in GHC.Generics Methods (==) :: U1 p -> U1 p -> Bool # (/=) :: U1 p -> U1 p -> Bool #
Eq (TypeRep a)	Since: base-2.1
Instance details Defined in Data.Typeable.Internal Methods (==) :: TypeRep a -> TypeRep a -> Bool # (/=) :: TypeRep a -> TypeRep a -> Bool #
(Eq a, Eq b) => Eq (a, b)
Instance details Defined in GHC.Classes Methods (==) :: (a, b) -> (a, b) -> Bool # (/=) :: (a, b) -> (a, b) -> Bool #
Eq a => Eq (Arg a b)	Since: base-4.9.0.0
Instance details Defined in Data.Semigroup Methods (==) :: Arg a b -> Arg a b -> Bool # (/=) :: Arg a b -> Arg a b -> Bool #
Eq (Proxy s)	Since: base-4.7.0.0
Instance details Defined in Data.Proxy Methods (==) :: Proxy s -> Proxy s -> Bool # (/=) :: Proxy s -> Proxy s -> Bool #
(Eq k, Eq a) => Eq (Map k a)
Instance details Defined in Data.Map.Internal Methods (==) :: Map k a -> Map k a -> Bool # (/=) :: Map k a -> Map k a -> Bool #
(Eq1 m, Eq a) => Eq (MaybeT m a)
Instance details Defined in Control.Monad.Trans.Maybe Methods (==) :: MaybeT m a -> MaybeT m a -> Bool # (/=) :: MaybeT m a -> MaybeT m a -> Bool #
(Eq k, Eq v) => Eq (HashMap k v)
Instance details Defined in Data.HashMap.Base Methods (==) :: HashMap k v -> HashMap k v -> Bool # (/=) :: HashMap k v -> HashMap k v -> Bool #
(Eq k, Eq v) => Eq (Leaf k v)
Instance details Defined in Data.HashMap.Base Methods (==) :: Leaf k v -> Leaf k v -> Bool # (/=) :: Leaf k v -> Leaf k v -> Bool #
Eq (f p) => Eq (Rec1 f p)	Since: base-4.7.0.0
Instance details Defined in GHC.Generics Methods (==) :: Rec1 f p -> Rec1 f p -> Bool # (/=) :: Rec1 f p -> Rec1 f p -> Bool #
Eq (URec (Ptr ()) p)	Since: base-4.9.0.0
Instance details Defined in GHC.Generics Methods (==) :: URec (Ptr ()) p -> URec (Ptr ()) p -> Bool # (/=) :: URec (Ptr ()) p -> URec (Ptr ()) p -> Bool #
Eq (URec Char p)	Since: base-4.9.0.0
Instance details Defined in GHC.Generics Methods (==) :: URec Char p -> URec Char p -> Bool # (/=) :: URec Char p -> URec Char p -> Bool #
Eq (URec Double p)	Since: base-4.9.0.0
Instance details Defined in GHC.Generics Methods (==) :: URec Double p -> URec Double p -> Bool # (/=) :: URec Double p -> URec Double p -> Bool #
Eq (URec Float p)
Instance details Defined in GHC.Generics Methods (==) :: URec Float p -> URec Float p -> Bool # (/=) :: URec Float p -> URec Float p -> Bool #
Eq (URec Int p)	Since: base-4.9.0.0
Instance details Defined in GHC.Generics Methods (==) :: URec Int p -> URec Int p -> Bool # (/=) :: URec Int p -> URec Int p -> Bool #
Eq (URec Word p)	Since: base-4.9.0.0
Instance details Defined in GHC.Generics Methods (==) :: URec Word p -> URec Word p -> Bool # (/=) :: URec Word p -> URec Word p -> Bool #
(Eq a, Eq b, Eq c) => Eq (a, b, c)
Instance details Defined in GHC.Classes Methods (==) :: (a, b, c) -> (a, b, c) -> Bool # (/=) :: (a, b, c) -> (a, b, c) -> Bool #
Eq a => Eq (Const a b)	Since: base-4.9.0.0
Instance details Defined in Data.Functor.Const Methods (==) :: Const a b -> Const a b -> Bool # (/=) :: Const a b -> Const a b -> Bool #
Eq (f a) => Eq (Ap f a)	Since: base-4.12.0.0
Instance details Defined in Data.Monoid Methods (==) :: Ap f a -> Ap f a -> Bool # (/=) :: Ap f a -> Ap f a -> Bool #
Eq (f a) => Eq (Alt f a)	Since: base-4.8.0.0
Instance details Defined in Data.Semigroup.Internal Methods (==) :: Alt f a -> Alt f a -> Bool # (/=) :: Alt f a -> Alt f a -> Bool #
Eq (a :~: b)	Since: base-4.7.0.0
Instance details Defined in Data.Type.Equality Methods (==) :: (a :~: b) -> (a :~: b) -> Bool # (/=) :: (a :~: b) -> (a :~: b) -> Bool #
(Eq e, Eq1 m, Eq a) => Eq (ExceptT e m a)
Instance details Defined in Control.Monad.Trans.Except Methods (==) :: ExceptT e m a -> ExceptT e m a -> Bool # (/=) :: ExceptT e m a -> ExceptT e m a -> Bool #
(Eq1 f, Eq a) => Eq (IdentityT f a)
Instance details Defined in Control.Monad.Trans.Identity Methods (==) :: IdentityT f a -> IdentityT f a -> Bool # (/=) :: IdentityT f a -> IdentityT f a -> Bool #
(Eq e, Eq1 m, Eq a) => Eq (ErrorT e m a)
Instance details Defined in Control.Monad.Trans.Error Methods (==) :: ErrorT e m a -> ErrorT e m a -> Bool # (/=) :: ErrorT e m a -> ErrorT e m a -> Bool #
Eq c => Eq (K1 i c p)	Since: base-4.7.0.0
Instance details Defined in GHC.Generics Methods (==) :: K1 i c p -> K1 i c p -> Bool # (/=) :: K1 i c p -> K1 i c p -> Bool #
(Eq (f p), Eq (g p)) => Eq ((f :+: g) p)	Since: base-4.7.0.0
Instance details Defined in GHC.Generics Methods (==) :: (f :+: g) p -> (f :+: g) p -> Bool # (/=) :: (f :+: g) p -> (f :+: g) p -> Bool #
(Eq (f p), Eq (g p)) => Eq ((f :*: g) p)	Since: base-4.7.0.0
Instance details Defined in GHC.Generics Methods (==) :: (f :: g) p -> (f :: g) p -> Bool # (/=) :: (f :: g) p -> (f :: g) p -> Bool #
(Eq a, Eq b, Eq c, Eq d) => Eq (a, b, c, d)
Instance details Defined in GHC.Classes Methods (==) :: (a, b, c, d) -> (a, b, c, d) -> Bool # (/=) :: (a, b, c, d) -> (a, b, c, d) -> Bool #
Eq (a :~~: b)	Since: base-4.10.0.0
Instance details Defined in Data.Type.Equality Methods (==) :: (a :~~: b) -> (a :~~: b) -> Bool # (/=) :: (a :~~: b) -> (a :~~: b) -> Bool #
Eq (f p) => Eq (M1 i c f p)	Since: base-4.7.0.0
Instance details Defined in GHC.Generics Methods (==) :: M1 i c f p -> M1 i c f p -> Bool # (/=) :: M1 i c f p -> M1 i c f p -> Bool #
Eq (f (g p)) => Eq ((f :.: g) p)	Since: base-4.7.0.0
Instance details Defined in GHC.Generics Methods (==) :: (f :.: g) p -> (f :.: g) p -> Bool # (/=) :: (f :.: g) p -> (f :.: g) p -> Bool #
(Eq a, Eq b, Eq c, Eq d, Eq e) => Eq (a, b, c, d, e)
Instance details Defined in GHC.Classes Methods (==) :: (a, b, c, d, e) -> (a, b, c, d, e) -> Bool # (/=) :: (a, b, c, d, e) -> (a, b, c, d, e) -> Bool #
(Eq1 f, Eq1 g, Eq a) => Eq (Compose f g a)	Since: base-4.9.0.0
Instance details Defined in Data.Functor.Compose Methods (==) :: Compose f g a -> Compose f g a -> Bool # (/=) :: Compose f g a -> Compose f g a -> Bool #
(Eq a, Eq b, Eq c, Eq d, Eq e, Eq f) => Eq (a, b, c, d, e, f)
Instance details Defined in GHC.Classes Methods (==) :: (a, b, c, d, e, f) -> (a, b, c, d, e, f) -> Bool # (/=) :: (a, b, c, d, e, f) -> (a, b, c, d, e, f) -> Bool #
(Eq a, Eq b, Eq c, Eq d, Eq e, Eq f, Eq g) => Eq (a, b, c, d, e, f, g)
Instance details Defined in GHC.Classes Methods (==) :: (a, b, c, d, e, f, g) -> (a, b, c, d, e, f, g) -> Bool # (/=) :: (a, b, c, d, e, f, g) -> (a, b, c, d, e, f, g) -> Bool #
(Eq a, Eq b, Eq c, Eq d, Eq e, Eq f, Eq g, Eq h) => Eq (a, b, c, d, e, f, g, h)
Instance details Defined in GHC.Classes Methods (==) :: (a, b, c, d, e, f, g, h) -> (a, b, c, d, e, f, g, h) -> Bool # (/=) :: (a, b, c, d, e, f, g, h) -> (a, b, c, d, e, f, g, h) -> Bool #
(Eq a, Eq b, Eq c, Eq d, Eq e, Eq f, Eq g, Eq h, Eq i) => Eq (a, b, c, d, e, f, g, h, i)
Instance details Defined in GHC.Classes Methods (==) :: (a, b, c, d, e, f, g, h, i) -> (a, b, c, d, e, f, g, h, i) -> Bool # (/=) :: (a, b, c, d, e, f, g, h, i) -> (a, b, c, d, e, f, g, h, i) -> Bool #
(Eq a, Eq b, Eq c, Eq d, Eq e, Eq f, Eq g, Eq h, Eq i, Eq j) => Eq (a, b, c, d, e, f, g, h, i, j)
Instance details Defined in GHC.Classes Methods (==) :: (a, b, c, d, e, f, g, h, i, j) -> (a, b, c, d, e, f, g, h, i, j) -> Bool # (/=) :: (a, b, c, d, e, f, g, h, i, j) -> (a, b, c, d, e, f, g, h, i, j) -> Bool #
(Eq a, Eq b, Eq c, Eq d, Eq e, Eq f, Eq g, Eq h, Eq i, Eq j, Eq k) => Eq (a, b, c, d, e, f, g, h, i, j, k)
Instance details Defined in GHC.Classes Methods (==) :: (a, b, c, d, e, f, g, h, i, j, k) -> (a, b, c, d, e, f, g, h, i, j, k) -> Bool # (/=) :: (a, b, c, d, e, f, g, h, i, j, k) -> (a, b, c, d, e, f, g, h, i, j, k) -> Bool #
(Eq a, Eq b, Eq c, Eq d, Eq e, Eq f, Eq g, Eq h, Eq i, Eq j, Eq k, Eq l) => Eq (a, b, c, d, e, f, g, h, i, j, k, l)
Instance details Defined in GHC.Classes Methods (==) :: (a, b, c, d, e, f, g, h, i, j, k, l) -> (a, b, c, d, e, f, g, h, i, j, k, l) -> Bool # (/=) :: (a, b, c, d, e, f, g, h, i, j, k, l) -> (a, b, c, d, e, f, g, h, i, j, k, l) -> Bool #
(Eq a, Eq b, Eq c, Eq d, Eq e, Eq f, Eq g, Eq h, Eq i, Eq j, Eq k, Eq l, Eq m) => Eq (a, b, c, d, e, f, g, h, i, j, k, l, m)
Instance details Defined in GHC.Classes Methods (==) :: (a, b, c, d, e, f, g, h, i, j, k, l, m) -> (a, b, c, d, e, f, g, h, i, j, k, l, m) -> Bool # (/=) :: (a, b, c, d, e, f, g, h, i, j, k, l, m) -> (a, b, c, d, e, f, g, h, i, j, k, l, m) -> Bool #
(Eq a, Eq b, Eq c, Eq d, Eq e, Eq f, Eq g, Eq h, Eq i, Eq j, Eq k, Eq l, Eq m, Eq n) => Eq (a, b, c, d, e, f, g, h, i, j, k, l, m, n)
Instance details Defined in GHC.Classes Methods (==) :: (a, b, c, d, e, f, g, h, i, j, k, l, m, n) -> (a, b, c, d, e, f, g, h, i, j, k, l, m, n) -> Bool # (/=) :: (a, b, c, d, e, f, g, h, i, j, k, l, m, n) -> (a, b, c, d, e, f, g, h, i, j, k, l, m, n) -> Bool #
(Eq a, Eq b, Eq c, Eq d, Eq e, Eq f, Eq g, Eq h, Eq i, Eq j, Eq k, Eq l, Eq m, Eq n, Eq o) => Eq (a, b, c, d, e, f, g, h, i, j, k, l, m, n, o)
Instance details Defined in GHC.Classes Methods (==) :: (a, b, c, d, e, f, g, h, i, j, k, l, m, n, o) -> (a, b, c, d, e, f, g, h, i, j, k, l, m, n, o) -> Bool # (/=) :: (a, b, c, d, e, f, g, h, i, j, k, l, m, n, o) -> (a, b, c, d, e, f, g, h, i, j, k, l, m, n, o) -> Bool #

class Fractional a => Floating a where #

Trigonometric and hyperbolic functions and related functions.

The Haskell Report defines no laws for Floating. However, '(+)', '(*)' and exp are customarily expected to define an exponential field and have the following properties:

exp (a + b) = @exp a * exp b
exp (fromInteger 0) = fromInteger 1

Minimal complete definition

pi, exp, log, sin, cos, asin, acos, atan, sinh, cosh, asinh, acosh, atanh

Methods

pi :: a #

exp :: a -> a #

sqrt :: a -> a #

(**) :: a -> a -> a infixr 8 #

logBase :: a -> a -> a #

sin :: a -> a #

cos :: a -> a #

tan :: a -> a #

asin :: a -> a #

acos :: a -> a #

atan :: a -> a #

sinh :: a -> a #

cosh :: a -> a #

tanh :: a -> a #

asinh :: a -> a #

acosh :: a -> a #

atanh :: a -> a #

Instances

Floating Double	Since: base-2.1
Instance details Defined in GHC.Float Methods pi :: Double # exp :: Double -> Double # log :: Double -> Double # sqrt :: Double -> Double # (**) :: Double -> Double -> Double # logBase :: Double -> Double -> Double # sin :: Double -> Double # cos :: Double -> Double # tan :: Double -> Double # asin :: Double -> Double # acos :: Double -> Double # atan :: Double -> Double # sinh :: Double -> Double # cosh :: Double -> Double # tanh :: Double -> Double # asinh :: Double -> Double # acosh :: Double -> Double # atanh :: Double -> Double # log1p :: Double -> Double # expm1 :: Double -> Double # log1pexp :: Double -> Double # log1mexp :: Double -> Double #
Floating Float	Since: base-2.1
Instance details Defined in GHC.Float Methods pi :: Float # exp :: Float -> Float # log :: Float -> Float # sqrt :: Float -> Float # (**) :: Float -> Float -> Float # logBase :: Float -> Float -> Float # sin :: Float -> Float # cos :: Float -> Float # tan :: Float -> Float # asin :: Float -> Float # acos :: Float -> Float # atan :: Float -> Float # sinh :: Float -> Float # cosh :: Float -> Float # tanh :: Float -> Float # asinh :: Float -> Float # acosh :: Float -> Float # atanh :: Float -> Float # log1p :: Float -> Float # expm1 :: Float -> Float # log1pexp :: Float -> Float # log1mexp :: Float -> Float #
Floating a => Floating (Identity a)	Since: base-4.9.0.0
Instance details Defined in Data.Functor.Identity Methods pi :: Identity a # exp :: Identity a -> Identity a # log :: Identity a -> Identity a # sqrt :: Identity a -> Identity a # (**) :: Identity a -> Identity a -> Identity a # logBase :: Identity a -> Identity a -> Identity a # sin :: Identity a -> Identity a # cos :: Identity a -> Identity a # tan :: Identity a -> Identity a # asin :: Identity a -> Identity a # acos :: Identity a -> Identity a # atan :: Identity a -> Identity a # sinh :: Identity a -> Identity a # cosh :: Identity a -> Identity a # tanh :: Identity a -> Identity a # asinh :: Identity a -> Identity a # acosh :: Identity a -> Identity a # atanh :: Identity a -> Identity a # log1p :: Identity a -> Identity a # expm1 :: Identity a -> Identity a # log1pexp :: Identity a -> Identity a # log1mexp :: Identity a -> Identity a #
Floating a => Floating (Const a b)	Since: base-4.9.0.0
Instance details Defined in Data.Functor.Const Methods pi :: Const a b # exp :: Const a b -> Const a b # log :: Const a b -> Const a b # sqrt :: Const a b -> Const a b # (**) :: Const a b -> Const a b -> Const a b # logBase :: Const a b -> Const a b -> Const a b # sin :: Const a b -> Const a b # cos :: Const a b -> Const a b # tan :: Const a b -> Const a b # asin :: Const a b -> Const a b # acos :: Const a b -> Const a b # atan :: Const a b -> Const a b # sinh :: Const a b -> Const a b # cosh :: Const a b -> Const a b # tanh :: Const a b -> Const a b # asinh :: Const a b -> Const a b # acosh :: Const a b -> Const a b # atanh :: Const a b -> Const a b # log1p :: Const a b -> Const a b # expm1 :: Const a b -> Const a b # log1pexp :: Const a b -> Const a b # log1mexp :: Const a b -> Const a b #

class Num a => Fractional a where #

Fractional numbers, supporting real division.

The Haskell Report defines no laws for Fractional. However, '(+)' and '(*)' are customarily expected to define a division ring and have the following properties:

recip gives the multiplicative inverse: x * recip x = recip x * x = fromInteger 1

Note that it isn't customarily expected that a type instance of Fractional implement a field. However, all instances in base do.

Minimal complete definition

fromRational, (recip | (/))

Methods

(/) :: a -> a -> a infixl 7 #

fractional division

recip :: a -> a #

reciprocal fraction

fromRational :: Rational -> a #

Conversion from a Rational (that is Ratio Integer). A floating literal stands for an application of fromRational to a value of type Rational, so such literals have type (Fractional a) => a.

Instances

Integral a => Fractional (Ratio a)	Since: base-2.0.1
Instance details Defined in GHC.Real Methods (/) :: Ratio a -> Ratio a -> Ratio a # recip :: Ratio a -> Ratio a # fromRational :: Rational -> Ratio a #
Fractional a => Fractional (Identity a)	Since: base-4.9.0.0
Instance details Defined in Data.Functor.Identity Methods (/) :: Identity a -> Identity a -> Identity a # recip :: Identity a -> Identity a # fromRational :: Rational -> Identity a #
Fractional a => Fractional (Const a b)	Since: base-4.9.0.0
Instance details Defined in Data.Functor.Const Methods (/) :: Const a b -> Const a b -> Const a b # recip :: Const a b -> Const a b # fromRational :: Rational -> Const a b #

class (Real a, Enum a) => Integral a where #

Integral numbers, supporting integer division.

The Haskell Report defines no laws for Integral. However, Integral instances are customarily expected to define a Euclidean domain and have the following properties for the 'div'/'mod' and 'quot'/'rem' pairs, given suitable Euclidean functions f and g:

x = y * quot x y + rem x y with rem x y = fromInteger 0 or g (rem x y) < g y
x = y * div x y + mod x y with mod x y = fromInteger 0 or f (mod x y) < f y

An example of a suitable Euclidean function, for Integer's instance, is abs.

Minimal complete definition

quotRem, toInteger

Methods

quot :: a -> a -> a infixl 7 #

integer division truncated toward zero

rem :: a -> a -> a infixl 7 #

integer remainder, satisfying

(x `quot` y)*y + (x `rem` y) == x

div :: a -> a -> a infixl 7 #

integer division truncated toward negative infinity

mod :: a -> a -> a infixl 7 #

integer modulus, satisfying

(x `div` y)*y + (x `mod` y) == x

quotRem :: a -> a -> (a, a) #

simultaneous quot and rem

divMod :: a -> a -> (a, a) #

simultaneous div and mod

toInteger :: a -> Integer #

conversion to Integer

Instances

Integral Int	Since: base-2.0.1
Instance details Defined in GHC.Real Methods quot :: Int -> Int -> Int # rem :: Int -> Int -> Int # div :: Int -> Int -> Int # mod :: Int -> Int -> Int # quotRem :: Int -> Int -> (Int, Int) # divMod :: Int -> Int -> (Int, Int) # toInteger :: Int -> Integer #
Integral Int8	Since: base-2.1
Instance details Defined in GHC.Int Methods quot :: Int8 -> Int8 -> Int8 # rem :: Int8 -> Int8 -> Int8 # div :: Int8 -> Int8 -> Int8 # mod :: Int8 -> Int8 -> Int8 # quotRem :: Int8 -> Int8 -> (Int8, Int8) # divMod :: Int8 -> Int8 -> (Int8, Int8) # toInteger :: Int8 -> Integer #
Integral Int16	Since: base-2.1
Instance details Defined in GHC.Int Methods quot :: Int16 -> Int16 -> Int16 # rem :: Int16 -> Int16 -> Int16 # div :: Int16 -> Int16 -> Int16 # mod :: Int16 -> Int16 -> Int16 # quotRem :: Int16 -> Int16 -> (Int16, Int16) # divMod :: Int16 -> Int16 -> (Int16, Int16) # toInteger :: Int16 -> Integer #
Integral Int32	Since: base-2.1
Instance details Defined in GHC.Int Methods quot :: Int32 -> Int32 -> Int32 # rem :: Int32 -> Int32 -> Int32 # div :: Int32 -> Int32 -> Int32 # mod :: Int32 -> Int32 -> Int32 # quotRem :: Int32 -> Int32 -> (Int32, Int32) # divMod :: Int32 -> Int32 -> (Int32, Int32) # toInteger :: Int32 -> Integer #
Integral Int64	Since: base-2.1
Instance details Defined in GHC.Int Methods quot :: Int64 -> Int64 -> Int64 # rem :: Int64 -> Int64 -> Int64 # div :: Int64 -> Int64 -> Int64 # mod :: Int64 -> Int64 -> Int64 # quotRem :: Int64 -> Int64 -> (Int64, Int64) # divMod :: Int64 -> Int64 -> (Int64, Int64) # toInteger :: Int64 -> Integer #
Integral Integer	Since: base-2.0.1
Instance details Defined in GHC.Real Methods quot :: Integer -> Integer -> Integer # rem :: Integer -> Integer -> Integer # div :: Integer -> Integer -> Integer # mod :: Integer -> Integer -> Integer # quotRem :: Integer -> Integer -> (Integer, Integer) # divMod :: Integer -> Integer -> (Integer, Integer) # toInteger :: Integer -> Integer #
Integral Natural	Since: base-4.8.0.0
Instance details Defined in GHC.Real Methods quot :: Natural -> Natural -> Natural # rem :: Natural -> Natural -> Natural # div :: Natural -> Natural -> Natural # mod :: Natural -> Natural -> Natural # quotRem :: Natural -> Natural -> (Natural, Natural) # divMod :: Natural -> Natural -> (Natural, Natural) # toInteger :: Natural -> Integer #
Integral Word	Since: base-2.1
Instance details Defined in GHC.Real Methods quot :: Word -> Word -> Word # rem :: Word -> Word -> Word # div :: Word -> Word -> Word # mod :: Word -> Word -> Word # quotRem :: Word -> Word -> (Word, Word) # divMod :: Word -> Word -> (Word, Word) # toInteger :: Word -> Integer #
Integral Word8	Since: base-2.1
Instance details Defined in GHC.Word Methods quot :: Word8 -> Word8 -> Word8 # rem :: Word8 -> Word8 -> Word8 # div :: Word8 -> Word8 -> Word8 # mod :: Word8 -> Word8 -> Word8 # quotRem :: Word8 -> Word8 -> (Word8, Word8) # divMod :: Word8 -> Word8 -> (Word8, Word8) # toInteger :: Word8 -> Integer #
Integral Word16	Since: base-2.1
Instance details Defined in GHC.Word Methods quot :: Word16 -> Word16 -> Word16 # rem :: Word16 -> Word16 -> Word16 # div :: Word16 -> Word16 -> Word16 # mod :: Word16 -> Word16 -> Word16 # quotRem :: Word16 -> Word16 -> (Word16, Word16) # divMod :: Word16 -> Word16 -> (Word16, Word16) # toInteger :: Word16 -> Integer #
Integral Word32	Since: base-2.1
Instance details Defined in GHC.Word Methods quot :: Word32 -> Word32 -> Word32 # rem :: Word32 -> Word32 -> Word32 # div :: Word32 -> Word32 -> Word32 # mod :: Word32 -> Word32 -> Word32 # quotRem :: Word32 -> Word32 -> (Word32, Word32) # divMod :: Word32 -> Word32 -> (Word32, Word32) # toInteger :: Word32 -> Integer #
Integral Word64	Since: base-2.1
Instance details Defined in GHC.Word Methods quot :: Word64 -> Word64 -> Word64 # rem :: Word64 -> Word64 -> Word64 # div :: Word64 -> Word64 -> Word64 # mod :: Word64 -> Word64 -> Word64 # quotRem :: Word64 -> Word64 -> (Word64, Word64) # divMod :: Word64 -> Word64 -> (Word64, Word64) # toInteger :: Word64 -> Integer #
Integral a => Integral (Identity a)	Since: base-4.9.0.0
Instance details Defined in Data.Functor.Identity Methods quot :: Identity a -> Identity a -> Identity a # rem :: Identity a -> Identity a -> Identity a # div :: Identity a -> Identity a -> Identity a # mod :: Identity a -> Identity a -> Identity a # quotRem :: Identity a -> Identity a -> (Identity a, Identity a) # divMod :: Identity a -> Identity a -> (Identity a, Identity a) # toInteger :: Identity a -> Integer #
Integral a => Integral (Const a b)	Since: base-4.9.0.0
Instance details Defined in Data.Functor.Const Methods quot :: Const a b -> Const a b -> Const a b # rem :: Const a b -> Const a b -> Const a b # div :: Const a b -> Const a b -> Const a b # mod :: Const a b -> Const a b -> Const a b # quotRem :: Const a b -> Const a b -> (Const a b, Const a b) # divMod :: Const a b -> Const a b -> (Const a b, Const a b) # toInteger :: Const a b -> Integer #

class Applicative m => Monad (m :: Type -> Type) where #

The Monad class defines the basic operations over a monad, a concept from a branch of mathematics known as category theory. From the perspective of a Haskell programmer, however, it is best to think of a monad as an abstract datatype of actions. Haskell's do expressions provide a convenient syntax for writing monadic expressions.

Instances of Monad should satisfy the following laws:

```
return a >>= k  =  k a
```
```
m >>= return  =  m
```

m >>= (\x -> k x >>= h)  =  (m >>= k) >>= h

Furthermore, the Monad and Applicative operations should relate as follows:

```
pure = return
```
```
(<*>) = ap
```

The above laws imply:

```
fmap f xs  =  xs >>= return . f
```
```
(>>) = (*>)
```

and that pure and (<*>) satisfy the applicative functor laws.

The instances of Monad for lists, Maybe and IO defined in the Prelude satisfy these laws.

Minimal complete definition

(>>=)

Methods

(>>=) :: m a -> (a -> m b) -> m b infixl 1 #

Sequentially compose two actions, passing any value produced by the first as an argument to the second.

(>>) :: m a -> m b -> m b infixl 1 #

Sequentially compose two actions, discarding any value produced by the first, like sequencing operators (such as the semicolon) in imperative languages.

return :: a -> m a #

Inject a value into the monadic type.

Instances

Monad []	Since: base-2.1
Instance details Defined in GHC.Base Methods (>>=) :: [a] -> (a -> [b]) -> [b] # (>>) :: [a] -> [b] -> [b] # return :: a -> [a] # fail :: String -> [a] #
Monad Maybe	Since: base-2.1
Instance details Defined in GHC.Base Methods (>>=) :: Maybe a -> (a -> Maybe b) -> Maybe b # (>>) :: Maybe a -> Maybe b -> Maybe b # return :: a -> Maybe a # fail :: String -> Maybe a #
Monad IO	Since: base-2.1
Instance details Defined in GHC.Base Methods (>>=) :: IO a -> (a -> IO b) -> IO b # (>>) :: IO a -> IO b -> IO b # return :: a -> IO a # fail :: String -> IO a #
Monad Par1	Since: base-4.9.0.0
Instance details Defined in GHC.Generics Methods (>>=) :: Par1 a -> (a -> Par1 b) -> Par1 b # (>>) :: Par1 a -> Par1 b -> Par1 b # return :: a -> Par1 a # fail :: String -> Par1 a #
Monad Min	Since: base-4.9.0.0
Instance details Defined in Data.Semigroup Methods (>>=) :: Min a -> (a -> Min b) -> Min b # (>>) :: Min a -> Min b -> Min b # return :: a -> Min a # fail :: String -> Min a #
Monad Max	Since: base-4.9.0.0
Instance details Defined in Data.Semigroup Methods (>>=) :: Max a -> (a -> Max b) -> Max b # (>>) :: Max a -> Max b -> Max b # return :: a -> Max a # fail :: String -> Max a #
Monad First	Since: base-4.9.0.0
Instance details Defined in Data.Semigroup Methods (>>=) :: First a -> (a -> First b) -> First b # (>>) :: First a -> First b -> First b # return :: a -> First a # fail :: String -> First a #
Monad Last	Since: base-4.9.0.0
Instance details Defined in Data.Semigroup Methods (>>=) :: Last a -> (a -> Last b) -> Last b # (>>) :: Last a -> Last b -> Last b # return :: a -> Last a # fail :: String -> Last a #
Monad Option	Since: base-4.9.0.0
Instance details Defined in Data.Semigroup Methods (>>=) :: Option a -> (a -> Option b) -> Option b # (>>) :: Option a -> Option b -> Option b # return :: a -> Option a # fail :: String -> Option a #
Monad Identity	Since: base-4.8.0.0
Instance details Defined in Data.Functor.Identity Methods (>>=) :: Identity a -> (a -> Identity b) -> Identity b # (>>) :: Identity a -> Identity b -> Identity b # return :: a -> Identity a # fail :: String -> Identity a #
Monad STM	Since: base-4.3.0.0
Instance details Defined in GHC.Conc.Sync Methods (>>=) :: STM a -> (a -> STM b) -> STM b # (>>) :: STM a -> STM b -> STM b # return :: a -> STM a # fail :: String -> STM a #
Monad First	Since: base-4.8.0.0
Instance details Defined in Data.Monoid Methods (>>=) :: First a -> (a -> First b) -> First b # (>>) :: First a -> First b -> First b # return :: a -> First a # fail :: String -> First a #
Monad Last	Since: base-4.8.0.0
Instance details Defined in Data.Monoid Methods (>>=) :: Last a -> (a -> Last b) -> Last b # (>>) :: Last a -> Last b -> Last b # return :: a -> Last a # fail :: String -> Last a #
Monad Dual	Since: base-4.8.0.0
Instance details Defined in Data.Semigroup.Internal Methods (>>=) :: Dual a -> (a -> Dual b) -> Dual b # (>>) :: Dual a -> Dual b -> Dual b # return :: a -> Dual a # fail :: String -> Dual a #
Monad Sum	Since: base-4.8.0.0
Instance details Defined in Data.Semigroup.Internal Methods (>>=) :: Sum a -> (a -> Sum b) -> Sum b # (>>) :: Sum a -> Sum b -> Sum b # return :: a -> Sum a # fail :: String -> Sum a #
Monad Product	Since: base-4.8.0.0
Instance details Defined in Data.Semigroup.Internal Methods (>>=) :: Product a -> (a -> Product b) -> Product b # (>>) :: Product a -> Product b -> Product b # return :: a -> Product a # fail :: String -> Product a #
Monad Down	Since: base-4.11.0.0
Instance details Defined in Data.Ord Methods (>>=) :: Down a -> (a -> Down b) -> Down b # (>>) :: Down a -> Down b -> Down b # return :: a -> Down a # fail :: String -> Down a #
Monad ReadP	Since: base-2.1
Instance details Defined in Text.ParserCombinators.ReadP Methods (>>=) :: ReadP a -> (a -> ReadP b) -> ReadP b # (>>) :: ReadP a -> ReadP b -> ReadP b # return :: a -> ReadP a # fail :: String -> ReadP a #
Monad NonEmpty	Since: base-4.9.0.0
Instance details Defined in GHC.Base Methods (>>=) :: NonEmpty a -> (a -> NonEmpty b) -> NonEmpty b # (>>) :: NonEmpty a -> NonEmpty b -> NonEmpty b # return :: a -> NonEmpty a # fail :: String -> NonEmpty a #
Monad Seq
Instance details Defined in Data.Sequence.Internal Methods (>>=) :: Seq a -> (a -> Seq b) -> Seq b # (>>) :: Seq a -> Seq b -> Seq b # return :: a -> Seq a # fail :: String -> Seq a #
Monad Vector
Instance details Defined in Data.Vector Methods (>>=) :: Vector a -> (a -> Vector b) -> Vector b # (>>) :: Vector a -> Vector b -> Vector b # return :: a -> Vector a # fail :: String -> Vector a #
Monad P	Since: base-2.1
Instance details Defined in Text.ParserCombinators.ReadP Methods (>>=) :: P a -> (a -> P b) -> P b # (>>) :: P a -> P b -> P b # return :: a -> P a # fail :: String -> P a #
Monad (Either e)	Since: base-4.4.0.0
Instance details Defined in Data.Either Methods (>>=) :: Either e a -> (a -> Either e b) -> Either e b # (>>) :: Either e a -> Either e b -> Either e b # return :: a -> Either e a # fail :: String -> Either e a #
Monad (U1 :: Type -> Type)	Since: base-4.9.0.0
Instance details Defined in GHC.Generics Methods (>>=) :: U1 a -> (a -> U1 b) -> U1 b # (>>) :: U1 a -> U1 b -> U1 b # return :: a -> U1 a # fail :: String -> U1 a #
Monoid a => Monad ((,) a)	Since: base-4.9.0.0
Instance details Defined in GHC.Base Methods (>>=) :: (a, a0) -> (a0 -> (a, b)) -> (a, b) # (>>) :: (a, a0) -> (a, b) -> (a, b) # return :: a0 -> (a, a0) # fail :: String -> (a, a0) #
Monad m => Monad (WrappedMonad m)	Since: base-4.7.0.0
Instance details Defined in Control.Applicative Methods (>>=) :: WrappedMonad m a -> (a -> WrappedMonad m b) -> WrappedMonad m b # (>>) :: WrappedMonad m a -> WrappedMonad m b -> WrappedMonad m b # return :: a -> WrappedMonad m a # fail :: String -> WrappedMonad m a #
ArrowApply a => Monad (ArrowMonad a)	Since: base-2.1
Instance details Defined in Control.Arrow Methods (>>=) :: ArrowMonad a a0 -> (a0 -> ArrowMonad a b) -> ArrowMonad a b # (>>) :: ArrowMonad a a0 -> ArrowMonad a b -> ArrowMonad a b # return :: a0 -> ArrowMonad a a0 # fail :: String -> ArrowMonad a a0 #
Monad (Proxy :: Type -> Type)	Since: base-4.7.0.0
Instance details Defined in Data.Proxy Methods (>>=) :: Proxy a -> (a -> Proxy b) -> Proxy b # (>>) :: Proxy a -> Proxy b -> Proxy b # return :: a -> Proxy a # fail :: String -> Proxy a #
Monad m => Monad (MaybeT m)
Instance details Defined in Control.Monad.Trans.Maybe Methods (>>=) :: MaybeT m a -> (a -> MaybeT m b) -> MaybeT m b # (>>) :: MaybeT m a -> MaybeT m b -> MaybeT m b # return :: a -> MaybeT m a # fail :: String -> MaybeT m a #
Monad f => Monad (Rec1 f)	Since: base-4.9.0.0
Instance details Defined in GHC.Generics Methods (>>=) :: Rec1 f a -> (a -> Rec1 f b) -> Rec1 f b # (>>) :: Rec1 f a -> Rec1 f b -> Rec1 f b # return :: a -> Rec1 f a # fail :: String -> Rec1 f a #
Monad f => Monad (Ap f)	Since: base-4.12.0.0
Instance details Defined in Data.Monoid Methods (>>=) :: Ap f a -> (a -> Ap f b) -> Ap f b # (>>) :: Ap f a -> Ap f b -> Ap f b # return :: a -> Ap f a # fail :: String -> Ap f a #
Monad f => Monad (Alt f)	Since: base-4.8.0.0
Instance details Defined in Data.Semigroup.Internal Methods (>>=) :: Alt f a -> (a -> Alt f b) -> Alt f b # (>>) :: Alt f a -> Alt f b -> Alt f b # return :: a -> Alt f a # fail :: String -> Alt f a #
(Applicative f, Monad f) => Monad (WhenMissing f x)	Equivalent to `ReaderT k (ReaderT x (MaybeT f))`. Since: containers-0.5.9
Instance details Defined in Data.IntMap.Internal Methods (>>=) :: WhenMissing f x a -> (a -> WhenMissing f x b) -> WhenMissing f x b # (>>) :: WhenMissing f x a -> WhenMissing f x b -> WhenMissing f x b # return :: a -> WhenMissing f x a # fail :: String -> WhenMissing f x a #
Monad m => Monad (ExceptT e m)
Instance details Defined in Control.Monad.Trans.Except Methods (>>=) :: ExceptT e m a -> (a -> ExceptT e m b) -> ExceptT e m b # (>>) :: ExceptT e m a -> ExceptT e m b -> ExceptT e m b # return :: a -> ExceptT e m a # fail :: String -> ExceptT e m a #
Monad m => Monad (IdentityT m)
Instance details Defined in Control.Monad.Trans.Identity Methods (>>=) :: IdentityT m a -> (a -> IdentityT m b) -> IdentityT m b # (>>) :: IdentityT m a -> IdentityT m b -> IdentityT m b # return :: a -> IdentityT m a # fail :: String -> IdentityT m a #
(Monad m, Error e) => Monad (ErrorT e m)
Instance details Defined in Control.Monad.Trans.Error Methods (>>=) :: ErrorT e m a -> (a -> ErrorT e m b) -> ErrorT e m b # (>>) :: ErrorT e m a -> ErrorT e m b -> ErrorT e m b # return :: a -> ErrorT e m a # fail :: String -> ErrorT e m a #
Monad m => Monad (StateT s m)
Instance details Defined in Control.Monad.Trans.State.Strict Methods (>>=) :: StateT s m a -> (a -> StateT s m b) -> StateT s m b # (>>) :: StateT s m a -> StateT s m b -> StateT s m b # return :: a -> StateT s m a # fail :: String -> StateT s m a #
Monad m => Monad (StateT s m)
Instance details Defined in Lens.Micro Methods (>>=) :: StateT s m a -> (a -> StateT s m b) -> StateT s m b # (>>) :: StateT s m a -> StateT s m b -> StateT s m b # return :: a -> StateT s m a # fail :: String -> StateT s m a #
Monad ((->) r :: Type -> Type)	Since: base-2.1
Instance details Defined in GHC.Base Methods (>>=) :: (r -> a) -> (a -> r -> b) -> r -> b # (>>) :: (r -> a) -> (r -> b) -> r -> b # return :: a -> r -> a # fail :: String -> r -> a #
(Monad f, Monad g) => Monad (f :*: g)	Since: base-4.9.0.0
Instance details Defined in GHC.Generics Methods (>>=) :: (f :: g) a -> (a -> (f :: g) b) -> (f :: g) b # (>>) :: (f :: g) a -> (f :: g) b -> (f :: g) b # return :: a -> (f :: g) a # fail :: String -> (f :: g) a #
(Monad f, Applicative f) => Monad (WhenMatched f x y)	Equivalent to `ReaderT Key (ReaderT x (ReaderT y (MaybeT f)))` Since: containers-0.5.9
Instance details Defined in Data.IntMap.Internal Methods (>>=) :: WhenMatched f x y a -> (a -> WhenMatched f x y b) -> WhenMatched f x y b # (>>) :: WhenMatched f x y a -> WhenMatched f x y b -> WhenMatched f x y b # return :: a -> WhenMatched f x y a # fail :: String -> WhenMatched f x y a #
(Applicative f, Monad f) => Monad (WhenMissing f k x)	Equivalent to `ReaderT k (ReaderT x (MaybeT f))` . Since: containers-0.5.9
Instance details Defined in Data.Map.Internal Methods (>>=) :: WhenMissing f k x a -> (a -> WhenMissing f k x b) -> WhenMissing f k x b # (>>) :: WhenMissing f k x a -> WhenMissing f k x b -> WhenMissing f k x b # return :: a -> WhenMissing f k x a # fail :: String -> WhenMissing f k x a #
Monad m => Monad (ReaderT r m)
Instance details Defined in Control.Monad.Trans.Reader Methods (>>=) :: ReaderT r m a -> (a -> ReaderT r m b) -> ReaderT r m b # (>>) :: ReaderT r m a -> ReaderT r m b -> ReaderT r m b # return :: a -> ReaderT r m a # fail :: String -> ReaderT r m a #
Monad f => Monad (M1 i c f)	Since: base-4.9.0.0
Instance details Defined in GHC.Generics Methods (>>=) :: M1 i c f a -> (a -> M1 i c f b) -> M1 i c f b # (>>) :: M1 i c f a -> M1 i c f b -> M1 i c f b # return :: a -> M1 i c f a # fail :: String -> M1 i c f a #
(Monad f, Applicative f) => Monad (WhenMatched f k x y)	Equivalent to `ReaderT k (ReaderT x (ReaderT y (MaybeT f)))` Since: containers-0.5.9
Instance details Defined in Data.Map.Internal Methods (>>=) :: WhenMatched f k x y a -> (a -> WhenMatched f k x y b) -> WhenMatched f k x y b # (>>) :: WhenMatched f k x y a -> WhenMatched f k x y b -> WhenMatched f k x y b # return :: a -> WhenMatched f k x y a # fail :: String -> WhenMatched f k x y a #

class Functor (f :: Type -> Type) where #

The Functor class is used for types that can be mapped over. Instances of Functor should satisfy the following laws:

fmap id  ==  id
fmap (f . g)  ==  fmap f . fmap g

The instances of Functor for lists, Maybe and IO satisfy these laws.

Minimal complete definition

fmap

Methods

fmap :: (a -> b) -> f a -> f b #

(<$) :: a -> f b -> f a infixl 4 #

Replace all locations in the input with the same value. The default definition is fmap . const, but this may be overridden with a more efficient version.

Instances

Functor []	Since: base-2.1
Instance details Defined in GHC.Base Methods fmap :: (a -> b) -> [a] -> [b] # (<$) :: a -> [b] -> [a] #
Functor Maybe	Since: base-2.1
Instance details Defined in GHC.Base Methods fmap :: (a -> b) -> Maybe a -> Maybe b # (<$) :: a -> Maybe b -> Maybe a #
Functor IO	Since: base-2.1
Instance details Defined in GHC.Base Methods fmap :: (a -> b) -> IO a -> IO b # (<$) :: a -> IO b -> IO a #
Functor Par1	Since: base-4.9.0.0
Instance details Defined in GHC.Generics Methods fmap :: (a -> b) -> Par1 a -> Par1 b # (<$) :: a -> Par1 b -> Par1 a #
Functor Min	Since: base-4.9.0.0
Instance details Defined in Data.Semigroup Methods fmap :: (a -> b) -> Min a -> Min b # (<$) :: a -> Min b -> Min a #
Functor Max	Since: base-4.9.0.0
Instance details Defined in Data.Semigroup Methods fmap :: (a -> b) -> Max a -> Max b # (<$) :: a -> Max b -> Max a #
Functor First	Since: base-4.9.0.0
Instance details Defined in Data.Semigroup Methods fmap :: (a -> b) -> First a -> First b # (<$) :: a -> First b -> First a #
Functor Last	Since: base-4.9.0.0
Instance details Defined in Data.Semigroup Methods fmap :: (a -> b) -> Last a -> Last b # (<$) :: a -> Last b -> Last a #
Functor Option	Since: base-4.9.0.0
Instance details Defined in Data.Semigroup Methods fmap :: (a -> b) -> Option a -> Option b # (<$) :: a -> Option b -> Option a #
Functor ZipList	Since: base-2.1
Instance details Defined in Control.Applicative Methods fmap :: (a -> b) -> ZipList a -> ZipList b # (<$) :: a -> ZipList b -> ZipList a #
Functor Identity	Since: base-4.8.0.0
Instance details Defined in Data.Functor.Identity Methods fmap :: (a -> b) -> Identity a -> Identity b # (<$) :: a -> Identity b -> Identity a #
Functor Handler	Since: base-4.6.0.0
Instance details Defined in Control.Exception Methods fmap :: (a -> b) -> Handler a -> Handler b # (<$) :: a -> Handler b -> Handler a #
Functor STM	Since: base-4.3.0.0
Instance details Defined in GHC.Conc.Sync Methods fmap :: (a -> b) -> STM a -> STM b # (<$) :: a -> STM b -> STM a #
Functor First	Since: base-4.8.0.0
Instance details Defined in Data.Monoid Methods fmap :: (a -> b) -> First a -> First b # (<$) :: a -> First b -> First a #
Functor Last	Since: base-4.8.0.0
Instance details Defined in Data.Monoid Methods fmap :: (a -> b) -> Last a -> Last b # (<$) :: a -> Last b -> Last a #
Functor Dual	Since: base-4.8.0.0
Instance details Defined in Data.Semigroup.Internal Methods fmap :: (a -> b) -> Dual a -> Dual b # (<$) :: a -> Dual b -> Dual a #
Functor Sum	Since: base-4.8.0.0
Instance details Defined in Data.Semigroup.Internal Methods fmap :: (a -> b) -> Sum a -> Sum b # (<$) :: a -> Sum b -> Sum a #
Functor Product	Since: base-4.8.0.0
Instance details Defined in Data.Semigroup.Internal Methods fmap :: (a -> b) -> Product a -> Product b # (<$) :: a -> Product b -> Product a #
Functor Down	Since: base-4.11.0.0
Instance details Defined in Data.Ord Methods fmap :: (a -> b) -> Down a -> Down b # (<$) :: a -> Down b -> Down a #
Functor ReadP	Since: base-2.1
Instance details Defined in Text.ParserCombinators.ReadP Methods fmap :: (a -> b) -> ReadP a -> ReadP b # (<$) :: a -> ReadP b -> ReadP a #
Functor NonEmpty	Since: base-4.9.0.0
Instance details Defined in GHC.Base Methods fmap :: (a -> b) -> NonEmpty a -> NonEmpty b # (<$) :: a -> NonEmpty b -> NonEmpty a #
Functor IntMap
Instance details Defined in Data.IntMap.Internal Methods fmap :: (a -> b) -> IntMap a -> IntMap b # (<$) :: a -> IntMap b -> IntMap a #
Functor Seq
Instance details Defined in Data.Sequence.Internal Methods fmap :: (a -> b) -> Seq a -> Seq b # (<$) :: a -> Seq b -> Seq a #
Functor FingerTree
Instance details Defined in Data.Sequence.Internal Methods fmap :: (a -> b) -> FingerTree a -> FingerTree b # (<$) :: a -> FingerTree b -> FingerTree a #
Functor Digit
Instance details Defined in Data.Sequence.Internal Methods fmap :: (a -> b) -> Digit a -> Digit b # (<$) :: a -> Digit b -> Digit a #
Functor Node
Instance details Defined in Data.Sequence.Internal Methods fmap :: (a -> b) -> Node a -> Node b # (<$) :: a -> Node b -> Node a #
Functor Elem
Instance details Defined in Data.Sequence.Internal Methods fmap :: (a -> b) -> Elem a -> Elem b # (<$) :: a -> Elem b -> Elem a #
Functor ViewL
Instance details Defined in Data.Sequence.Internal Methods fmap :: (a -> b) -> ViewL a -> ViewL b # (<$) :: a -> ViewL b -> ViewL a #
Functor ViewR
Instance details Defined in Data.Sequence.Internal Methods fmap :: (a -> b) -> ViewR a -> ViewR b # (<$) :: a -> ViewR b -> ViewR a #
Functor Vector
Instance details Defined in Data.Vector Methods fmap :: (a -> b) -> Vector a -> Vector b # (<$) :: a -> Vector b -> Vector a #
Functor P	Since: base-4.8.0.0
Instance details Defined in Text.ParserCombinators.ReadP Methods fmap :: (a -> b) -> P a -> P b # (<$) :: a -> P b -> P a #
Functor (Either a)	Since: base-3.0
Instance details Defined in Data.Either Methods fmap :: (a0 -> b) -> Either a a0 -> Either a b # (<$) :: a0 -> Either a b -> Either a a0 #
Functor (V1 :: Type -> Type)	Since: base-4.9.0.0
Instance details Defined in GHC.Generics Methods fmap :: (a -> b) -> V1 a -> V1 b # (<$) :: a -> V1 b -> V1 a #
Functor (U1 :: Type -> Type)	Since: base-4.9.0.0
Instance details Defined in GHC.Generics Methods fmap :: (a -> b) -> U1 a -> U1 b # (<$) :: a -> U1 b -> U1 a #
Functor ((,) a)	Since: base-2.1
Instance details Defined in GHC.Base Methods fmap :: (a0 -> b) -> (a, a0) -> (a, b) # (<$) :: a0 -> (a, b) -> (a, a0) #
Functor (Arg a)	Since: base-4.9.0.0
Instance details Defined in Data.Semigroup Methods fmap :: (a0 -> b) -> Arg a a0 -> Arg a b # (<$) :: a0 -> Arg a b -> Arg a a0 #
Monad m => Functor (WrappedMonad m)	Since: base-2.1
Instance details Defined in Control.Applicative Methods fmap :: (a -> b) -> WrappedMonad m a -> WrappedMonad m b # (<$) :: a -> WrappedMonad m b -> WrappedMonad m a #
Arrow a => Functor (ArrowMonad a)	Since: base-4.6.0.0
Instance details Defined in Control.Arrow Methods fmap :: (a0 -> b) -> ArrowMonad a a0 -> ArrowMonad a b # (<$) :: a0 -> ArrowMonad a b -> ArrowMonad a a0 #
Functor (Proxy :: Type -> Type)	Since: base-4.7.0.0
Instance details Defined in Data.Proxy Methods fmap :: (a -> b) -> Proxy a -> Proxy b # (<$) :: a -> Proxy b -> Proxy a #
Functor (Map k)
Instance details Defined in Data.Map.Internal Methods fmap :: (a -> b) -> Map k a -> Map k b # (<$) :: a -> Map k b -> Map k a #
Functor m => Functor (MaybeT m)
Instance details Defined in Control.Monad.Trans.Maybe Methods fmap :: (a -> b) -> MaybeT m a -> MaybeT m b # (<$) :: a -> MaybeT m b -> MaybeT m a #
Monad m => Functor (Handler m)
Instance details Defined in Control.Monad.Catch Methods fmap :: (a -> b) -> Handler m a -> Handler m b # (<$) :: a -> Handler m b -> Handler m a #
Functor (HashMap k)
Instance details Defined in Data.HashMap.Base Methods fmap :: (a -> b) -> HashMap k a -> HashMap k b # (<$) :: a -> HashMap k b -> HashMap k a #
Functor f => Functor (Rec1 f)	Since: base-4.9.0.0
Instance details Defined in GHC.Generics Methods fmap :: (a -> b) -> Rec1 f a -> Rec1 f b # (<$) :: a -> Rec1 f b -> Rec1 f a #
Functor (URec Char :: Type -> Type)	Since: base-4.9.0.0
Instance details Defined in GHC.Generics Methods fmap :: (a -> b) -> URec Char a -> URec Char b # (<$) :: a -> URec Char b -> URec Char a #
Functor (URec Double :: Type -> Type)	Since: base-4.9.0.0
Instance details Defined in GHC.Generics Methods fmap :: (a -> b) -> URec Double a -> URec Double b # (<$) :: a -> URec Double b -> URec Double a #
Functor (URec Float :: Type -> Type)	Since: base-4.9.0.0
Instance details Defined in GHC.Generics Methods fmap :: (a -> b) -> URec Float a -> URec Float b # (<$) :: a -> URec Float b -> URec Float a #
Functor (URec Int :: Type -> Type)	Since: base-4.9.0.0
Instance details Defined in GHC.Generics Methods fmap :: (a -> b) -> URec Int a -> URec Int b # (<$) :: a -> URec Int b -> URec Int a #
Functor (URec Word :: Type -> Type)	Since: base-4.9.0.0
Instance details Defined in GHC.Generics Methods fmap :: (a -> b) -> URec Word a -> URec Word b # (<$) :: a -> URec Word b -> URec Word a #
Functor (URec (Ptr ()) :: Type -> Type)	Since: base-4.9.0.0
Instance details Defined in GHC.Generics Methods fmap :: (a -> b) -> URec (Ptr ()) a -> URec (Ptr ()) b # (<$) :: a -> URec (Ptr ()) b -> URec (Ptr ()) a #
Arrow a => Functor (WrappedArrow a b)	Since: base-2.1
Instance details Defined in Control.Applicative Methods fmap :: (a0 -> b0) -> WrappedArrow a b a0 -> WrappedArrow a b b0 # (<$) :: a0 -> WrappedArrow a b b0 -> WrappedArrow a b a0 #
Functor (Const m :: Type -> Type)	Since: base-2.1
Instance details Defined in Data.Functor.Const Methods fmap :: (a -> b) -> Const m a -> Const m b # (<$) :: a -> Const m b -> Const m a #
Functor f => Functor (Ap f)	Since: base-4.12.0.0
Instance details Defined in Data.Monoid Methods fmap :: (a -> b) -> Ap f a -> Ap f b # (<$) :: a -> Ap f b -> Ap f a #
Functor f => Functor (Alt f)	Since: base-4.8.0.0
Instance details Defined in Data.Semigroup.Internal Methods fmap :: (a -> b) -> Alt f a -> Alt f b # (<$) :: a -> Alt f b -> Alt f a #
(Applicative f, Monad f) => Functor (WhenMissing f x)	Since: containers-0.5.9
Instance details Defined in Data.IntMap.Internal Methods fmap :: (a -> b) -> WhenMissing f x a -> WhenMissing f x b # (<$) :: a -> WhenMissing f x b -> WhenMissing f x a #
Functor m => Functor (ExceptT e m)
Instance details Defined in Control.Monad.Trans.Except Methods fmap :: (a -> b) -> ExceptT e m a -> ExceptT e m b # (<$) :: a -> ExceptT e m b -> ExceptT e m a #
Functor m => Functor (IdentityT m)
Instance details Defined in Control.Monad.Trans.Identity Methods fmap :: (a -> b) -> IdentityT m a -> IdentityT m b # (<$) :: a -> IdentityT m b -> IdentityT m a #
Functor m => Functor (ErrorT e m)
Instance details Defined in Control.Monad.Trans.Error Methods fmap :: (a -> b) -> ErrorT e m a -> ErrorT e m b # (<$) :: a -> ErrorT e m b -> ErrorT e m a #
Functor m => Functor (StateT s m)
Instance details Defined in Control.Monad.Trans.State.Strict Methods fmap :: (a -> b) -> StateT s m a -> StateT s m b # (<$) :: a -> StateT s m b -> StateT s m a #
Functor (Bazaar a b)
Instance details Defined in Lens.Micro Methods fmap :: (a0 -> b0) -> Bazaar a b a0 -> Bazaar a b b0 # (<$) :: a0 -> Bazaar a b b0 -> Bazaar a b a0 #
Functor m => Functor (StateT s m)
Instance details Defined in Lens.Micro Methods fmap :: (a -> b) -> StateT s m a -> StateT s m b # (<$) :: a -> StateT s m b -> StateT s m a #
Functor ((->) r :: Type -> Type)	Since: base-2.1
Instance details Defined in GHC.Base Methods fmap :: (a -> b) -> (r -> a) -> r -> b # (<$) :: a -> (r -> b) -> r -> a #
Functor (K1 i c :: Type -> Type)	Since: base-4.9.0.0
Instance details Defined in GHC.Generics Methods fmap :: (a -> b) -> K1 i c a -> K1 i c b # (<$) :: a -> K1 i c b -> K1 i c a #
(Functor f, Functor g) => Functor (f :+: g)	Since: base-4.9.0.0
Instance details Defined in GHC.Generics Methods fmap :: (a -> b) -> (f :+: g) a -> (f :+: g) b # (<$) :: a -> (f :+: g) b -> (f :+: g) a #
(Functor f, Functor g) => Functor (f :*: g)	Since: base-4.9.0.0
Instance details Defined in GHC.Generics Methods fmap :: (a -> b) -> (f :: g) a -> (f :: g) b # (<$) :: a -> (f :: g) b -> (f :: g) a #
Functor f => Functor (WhenMatched f x y)	Since: containers-0.5.9
Instance details Defined in Data.IntMap.Internal Methods fmap :: (a -> b) -> WhenMatched f x y a -> WhenMatched f x y b # (<$) :: a -> WhenMatched f x y b -> WhenMatched f x y a #
(Applicative f, Monad f) => Functor (WhenMissing f k x)	Since: containers-0.5.9
Instance details Defined in Data.Map.Internal Methods fmap :: (a -> b) -> WhenMissing f k x a -> WhenMissing f k x b # (<$) :: a -> WhenMissing f k x b -> WhenMissing f k x a #
Functor m => Functor (ReaderT r m)
Instance details Defined in Control.Monad.Trans.Reader Methods fmap :: (a -> b) -> ReaderT r m a -> ReaderT r m b # (<$) :: a -> ReaderT r m b -> ReaderT r m a #
Functor f => Functor (M1 i c f)	Since: base-4.9.0.0
Instance details Defined in GHC.Generics Methods fmap :: (a -> b) -> M1 i c f a -> M1 i c f b # (<$) :: a -> M1 i c f b -> M1 i c f a #
(Functor f, Functor g) => Functor (f :.: g)	Since: base-4.9.0.0
Instance details Defined in GHC.Generics Methods fmap :: (a -> b) -> (f :.: g) a -> (f :.: g) b # (<$) :: a -> (f :.: g) b -> (f :.: g) a #
(Functor f, Functor g) => Functor (Compose f g)	Since: base-4.9.0.0
Instance details Defined in Data.Functor.Compose Methods fmap :: (a -> b) -> Compose f g a -> Compose f g b # (<$) :: a -> Compose f g b -> Compose f g a #
Functor f => Functor (WhenMatched f k x y)	Since: containers-0.5.9
Instance details Defined in Data.Map.Internal Methods fmap :: (a -> b) -> WhenMatched f k x y a -> WhenMatched f k x y b # (<$) :: a -> WhenMatched f k x y b -> WhenMatched f k x y a #

class Num a where #

Basic numeric class.

The Haskell Report defines no laws for Num. However, '(+)' and '(*)' are customarily expected to define a ring and have the following properties:

Associativity of (+): (x + y) + z = x + (y + z)
Commutativity of (+): x + y = y + x
fromInteger 0 is the additive identity: x + fromInteger 0 = x
negate gives the additive inverse: x + negate x = fromInteger 0
Associativity of (*): (x * y) * z = x * (y * z)
fromInteger 1 is the multiplicative identity: x * fromInteger 1 = x and fromInteger 1 * x = x
Distributivity of (*) with respect to (+): a * (b + c) = (a * b) + (a * c) and (b + c) * a = (b * a) + (c * a)

Note that it isn't customarily expected that a type instance of both Num and Ord implement an ordered ring. Indeed, in base only Integer and Rational do.

Minimal complete definition

(+), (*), abs, signum, fromInteger, (negate | (-))

Methods

(+) :: a -> a -> a infixl 6 #

(-) :: a -> a -> a infixl 6 #

(*) :: a -> a -> a infixl 7 #

negate :: a -> a #

Unary negation.

abs :: a -> a #

Absolute value.

signum :: a -> a #

Sign of a number. The functions abs and signum should satisfy the law:

abs x * signum x == x

For real numbers, the signum is either -1 (negative), 0 (zero) or 1 (positive).

fromInteger :: Integer -> a #

Conversion from an Integer. An integer literal represents the application of the function fromInteger to the appropriate value of type Integer, so such literals have type (Num a) => a.

Instances

Num Int	Since: base-2.1
Instance details Defined in GHC.Num Methods (+) :: Int -> Int -> Int # (-) :: Int -> Int -> Int # (*) :: Int -> Int -> Int # negate :: Int -> Int # abs :: Int -> Int # signum :: Int -> Int # fromInteger :: Integer -> Int #
Num Int8	Since: base-2.1
Instance details Defined in GHC.Int Methods (+) :: Int8 -> Int8 -> Int8 # (-) :: Int8 -> Int8 -> Int8 # (*) :: Int8 -> Int8 -> Int8 # negate :: Int8 -> Int8 # abs :: Int8 -> Int8 # signum :: Int8 -> Int8 # fromInteger :: Integer -> Int8 #
Num Int16	Since: base-2.1
Instance details Defined in GHC.Int Methods (+) :: Int16 -> Int16 -> Int16 # (-) :: Int16 -> Int16 -> Int16 # (*) :: Int16 -> Int16 -> Int16 # negate :: Int16 -> Int16 # abs :: Int16 -> Int16 # signum :: Int16 -> Int16 # fromInteger :: Integer -> Int16 #
Num Int32	Since: base-2.1
Instance details Defined in GHC.Int Methods (+) :: Int32 -> Int32 -> Int32 # (-) :: Int32 -> Int32 -> Int32 # (*) :: Int32 -> Int32 -> Int32 # negate :: Int32 -> Int32 # abs :: Int32 -> Int32 # signum :: Int32 -> Int32 # fromInteger :: Integer -> Int32 #
Num Int64	Since: base-2.1
Instance details Defined in GHC.Int Methods (+) :: Int64 -> Int64 -> Int64 # (-) :: Int64 -> Int64 -> Int64 # (*) :: Int64 -> Int64 -> Int64 # negate :: Int64 -> Int64 # abs :: Int64 -> Int64 # signum :: Int64 -> Int64 # fromInteger :: Integer -> Int64 #
Num Integer	Since: base-2.1
Instance details Defined in GHC.Num Methods (+) :: Integer -> Integer -> Integer # (-) :: Integer -> Integer -> Integer # (*) :: Integer -> Integer -> Integer # negate :: Integer -> Integer # abs :: Integer -> Integer # signum :: Integer -> Integer # fromInteger :: Integer -> Integer #
Num Natural	Note that `Natural`'s `Num` instance isn't a ring: no element but 0 has an additive inverse. It is a semiring though. Since: base-4.8.0.0
Instance details Defined in GHC.Num Methods (+) :: Natural -> Natural -> Natural # (-) :: Natural -> Natural -> Natural # (*) :: Natural -> Natural -> Natural # negate :: Natural -> Natural # abs :: Natural -> Natural # signum :: Natural -> Natural # fromInteger :: Integer -> Natural #
Num Word	Since: base-2.1
Instance details Defined in GHC.Num Methods (+) :: Word -> Word -> Word # (-) :: Word -> Word -> Word # (*) :: Word -> Word -> Word # negate :: Word -> Word # abs :: Word -> Word # signum :: Word -> Word # fromInteger :: Integer -> Word #
Num Word8	Since: base-2.1
Instance details Defined in GHC.Word Methods (+) :: Word8 -> Word8 -> Word8 # (-) :: Word8 -> Word8 -> Word8 # (*) :: Word8 -> Word8 -> Word8 # negate :: Word8 -> Word8 # abs :: Word8 -> Word8 # signum :: Word8 -> Word8 # fromInteger :: Integer -> Word8 #
Num Word16	Since: base-2.1
Instance details Defined in GHC.Word Methods (+) :: Word16 -> Word16 -> Word16 # (-) :: Word16 -> Word16 -> Word16 # (*) :: Word16 -> Word16 -> Word16 # negate :: Word16 -> Word16 # abs :: Word16 -> Word16 # signum :: Word16 -> Word16 # fromInteger :: Integer -> Word16 #
Num Word32	Since: base-2.1
Instance details Defined in GHC.Word Methods (+) :: Word32 -> Word32 -> Word32 # (-) :: Word32 -> Word32 -> Word32 # (*) :: Word32 -> Word32 -> Word32 # negate :: Word32 -> Word32 # abs :: Word32 -> Word32 # signum :: Word32 -> Word32 # fromInteger :: Integer -> Word32 #
Num Word64	Since: base-2.1
Instance details Defined in GHC.Word Methods (+) :: Word64 -> Word64 -> Word64 # (-) :: Word64 -> Word64 -> Word64 # (*) :: Word64 -> Word64 -> Word64 # negate :: Word64 -> Word64 # abs :: Word64 -> Word64 # signum :: Word64 -> Word64 # fromInteger :: Integer -> Word64 #
Num CodePoint
Instance details Defined in Data.Text.Encoding Methods (+) :: CodePoint -> CodePoint -> CodePoint # (-) :: CodePoint -> CodePoint -> CodePoint # (*) :: CodePoint -> CodePoint -> CodePoint # negate :: CodePoint -> CodePoint # abs :: CodePoint -> CodePoint # signum :: CodePoint -> CodePoint # fromInteger :: Integer -> CodePoint #
Num DecoderState
Instance details Defined in Data.Text.Encoding Methods (+) :: DecoderState -> DecoderState -> DecoderState # (-) :: DecoderState -> DecoderState -> DecoderState # (*) :: DecoderState -> DecoderState -> DecoderState # negate :: DecoderState -> DecoderState # abs :: DecoderState -> DecoderState # signum :: DecoderState -> DecoderState # fromInteger :: Integer -> DecoderState #
Integral a => Num (Ratio a)	Since: base-2.0.1
Instance details Defined in GHC.Real Methods (+) :: Ratio a -> Ratio a -> Ratio a # (-) :: Ratio a -> Ratio a -> Ratio a # (*) :: Ratio a -> Ratio a -> Ratio a # negate :: Ratio a -> Ratio a # abs :: Ratio a -> Ratio a # signum :: Ratio a -> Ratio a # fromInteger :: Integer -> Ratio a #
Num a => Num (Min a)	Since: base-4.9.0.0
Instance details Defined in Data.Semigroup Methods (+) :: Min a -> Min a -> Min a # (-) :: Min a -> Min a -> Min a # (*) :: Min a -> Min a -> Min a # negate :: Min a -> Min a # abs :: Min a -> Min a # signum :: Min a -> Min a # fromInteger :: Integer -> Min a #
Num a => Num (Max a)	Since: base-4.9.0.0
Instance details Defined in Data.Semigroup Methods (+) :: Max a -> Max a -> Max a # (-) :: Max a -> Max a -> Max a # (*) :: Max a -> Max a -> Max a # negate :: Max a -> Max a # abs :: Max a -> Max a # signum :: Max a -> Max a # fromInteger :: Integer -> Max a #
Num a => Num (Identity a)	Since: base-4.9.0.0
Instance details Defined in Data.Functor.Identity Methods (+) :: Identity a -> Identity a -> Identity a # (-) :: Identity a -> Identity a -> Identity a # (*) :: Identity a -> Identity a -> Identity a # negate :: Identity a -> Identity a # abs :: Identity a -> Identity a # signum :: Identity a -> Identity a # fromInteger :: Integer -> Identity a #
Num a => Num (Sum a)	Since: base-4.7.0.0
Instance details Defined in Data.Semigroup.Internal Methods (+) :: Sum a -> Sum a -> Sum a # (-) :: Sum a -> Sum a -> Sum a # (*) :: Sum a -> Sum a -> Sum a # negate :: Sum a -> Sum a # abs :: Sum a -> Sum a # signum :: Sum a -> Sum a # fromInteger :: Integer -> Sum a #
Num a => Num (Product a)	Since: base-4.7.0.0
Instance details Defined in Data.Semigroup.Internal Methods (+) :: Product a -> Product a -> Product a # (-) :: Product a -> Product a -> Product a # (*) :: Product a -> Product a -> Product a # negate :: Product a -> Product a # abs :: Product a -> Product a # signum :: Product a -> Product a # fromInteger :: Integer -> Product a #
Num a => Num (Down a)	Since: base-4.11.0.0
Instance details Defined in Data.Ord Methods (+) :: Down a -> Down a -> Down a # (-) :: Down a -> Down a -> Down a # (*) :: Down a -> Down a -> Down a # negate :: Down a -> Down a # abs :: Down a -> Down a # signum :: Down a -> Down a # fromInteger :: Integer -> Down a #
Num a => Num (Const a b)	Since: base-4.9.0.0
Instance details Defined in Data.Functor.Const Methods (+) :: Const a b -> Const a b -> Const a b # (-) :: Const a b -> Const a b -> Const a b # (*) :: Const a b -> Const a b -> Const a b # negate :: Const a b -> Const a b # abs :: Const a b -> Const a b # signum :: Const a b -> Const a b # fromInteger :: Integer -> Const a b #
(Applicative f, Num a) => Num (Ap f a)	Since: base-4.12.0.0
Instance details Defined in Data.Monoid Methods (+) :: Ap f a -> Ap f a -> Ap f a # (-) :: Ap f a -> Ap f a -> Ap f a # (*) :: Ap f a -> Ap f a -> Ap f a # negate :: Ap f a -> Ap f a # abs :: Ap f a -> Ap f a # signum :: Ap f a -> Ap f a # fromInteger :: Integer -> Ap f a #
Num (f a) => Num (Alt f a)	Since: base-4.8.0.0
Instance details Defined in Data.Semigroup.Internal Methods (+) :: Alt f a -> Alt f a -> Alt f a # (-) :: Alt f a -> Alt f a -> Alt f a # (*) :: Alt f a -> Alt f a -> Alt f a # negate :: Alt f a -> Alt f a # abs :: Alt f a -> Alt f a # signum :: Alt f a -> Alt f a # fromInteger :: Integer -> Alt f a #

class Eq a => Ord a where #

The Ord class is used for totally ordered datatypes.

Instances of Ord can be derived for any user-defined datatype whose constituent types are in Ord. The declared order of the constructors in the data declaration determines the ordering in derived Ord instances. The Ordering datatype allows a single comparison to determine the precise ordering of two objects.

The Haskell Report defines no laws for Ord. However, <= is customarily expected to implement a non-strict partial order and have the following properties:

Transitivity: if x <= y && y <= z = True, then x <= z = True
Reflexivity: x <= x = True
Antisymmetry: if x <= y && y <= x = True, then x == y = True

Note that the following operator interactions are expected to hold:

x >= y = y <= x
x < y = x <= y && x /= y
x > y = y < x
x < y = compare x y == LT
x > y = compare x y == GT
x == y = compare x y == EQ
min x y == if x <= y then x else y = True
max x y == if x >= y then x else y = True

Minimal complete definition: either compare or <=. Using compare can be more efficient for complex types.

Minimal complete definition

compare | (<=)

Methods

compare :: a -> a -> Ordering #

(<) :: a -> a -> Bool infix 4 #

(<=) :: a -> a -> Bool infix 4 #

(>) :: a -> a -> Bool infix 4 #

(>=) :: a -> a -> Bool infix 4 #

max :: a -> a -> a #

min :: a -> a -> a #

Instances

Ord Bool
Instance details Defined in GHC.Classes Methods compare :: Bool -> Bool -> Ordering # (<) :: Bool -> Bool -> Bool # (<=) :: Bool -> Bool -> Bool # (>) :: Bool -> Bool -> Bool # (>=) :: Bool -> Bool -> Bool # max :: Bool -> Bool -> Bool # min :: Bool -> Bool -> Bool #
Ord Char
Instance details Defined in GHC.Classes Methods compare :: Char -> Char -> Ordering # (<) :: Char -> Char -> Bool # (<=) :: Char -> Char -> Bool # (>) :: Char -> Char -> Bool # (>=) :: Char -> Char -> Bool # max :: Char -> Char -> Char # min :: Char -> Char -> Char #
Ord Double	Note that due to the presence of `NaN`, `Double`'s `Ord` instance does not satisfy reflexivity. `>>>` `0/0 <= (0/0 :: Double)`False Also note that, due to the same, `Ord`'s operator interactions are not respected by `Double`'s instance: `>>>` `(0/0 :: Double) > 1`False `>>>` `compare (0/0 :: Double) 1`GT
Instance details Defined in GHC.Classes Methods compare :: Double -> Double -> Ordering # (<) :: Double -> Double -> Bool # (<=) :: Double -> Double -> Bool # (>) :: Double -> Double -> Bool # (>=) :: Double -> Double -> Bool # max :: Double -> Double -> Double # min :: Double -> Double -> Double #
Ord Float	Note that due to the presence of `NaN`, `Float`'s `Ord` instance does not satisfy reflexivity. `>>>` `0/0 <= (0/0 :: Float)`False Also note that, due to the same, `Ord`'s operator interactions are not respected by `Float`'s instance: `>>>` `(0/0 :: Float) > 1`False `>>>` `compare (0/0 :: Float) 1`GT
Instance details Defined in GHC.Classes Methods compare :: Float -> Float -> Ordering # (<) :: Float -> Float -> Bool # (<=) :: Float -> Float -> Bool # (>) :: Float -> Float -> Bool # (>=) :: Float -> Float -> Bool # max :: Float -> Float -> Float # min :: Float -> Float -> Float #
Ord Int
Instance details Defined in GHC.Classes Methods compare :: Int -> Int -> Ordering # (<) :: Int -> Int -> Bool # (<=) :: Int -> Int -> Bool # (>) :: Int -> Int -> Bool # (>=) :: Int -> Int -> Bool # max :: Int -> Int -> Int # min :: Int -> Int -> Int #
Ord Int8	Since: base-2.1
Instance details Defined in GHC.Int Methods compare :: Int8 -> Int8 -> Ordering # (<) :: Int8 -> Int8 -> Bool # (<=) :: Int8 -> Int8 -> Bool # (>) :: Int8 -> Int8 -> Bool # (>=) :: Int8 -> Int8 -> Bool # max :: Int8 -> Int8 -> Int8 # min :: Int8 -> Int8 -> Int8 #
Ord Int16	Since: base-2.1
Instance details Defined in GHC.Int Methods compare :: Int16 -> Int16 -> Ordering # (<) :: Int16 -> Int16 -> Bool # (<=) :: Int16 -> Int16 -> Bool # (>) :: Int16 -> Int16 -> Bool # (>=) :: Int16 -> Int16 -> Bool # max :: Int16 -> Int16 -> Int16 # min :: Int16 -> Int16 -> Int16 #
Ord Int32	Since: base-2.1
Instance details Defined in GHC.Int Methods compare :: Int32 -> Int32 -> Ordering # (<) :: Int32 -> Int32 -> Bool # (<=) :: Int32 -> Int32 -> Bool # (>) :: Int32 -> Int32 -> Bool # (>=) :: Int32 -> Int32 -> Bool # max :: Int32 -> Int32 -> Int32 # min :: Int32 -> Int32 -> Int32 #
Ord Int64	Since: base-2.1
Instance details Defined in GHC.Int Methods compare :: Int64 -> Int64 -> Ordering # (<) :: Int64 -> Int64 -> Bool # (<=) :: Int64 -> Int64 -> Bool # (>) :: Int64 -> Int64 -> Bool # (>=) :: Int64 -> Int64 -> Bool # max :: Int64 -> Int64 -> Int64 # min :: Int64 -> Int64 -> Int64 #
Ord Integer
Instance details Defined in GHC.Integer.Type Methods compare :: Integer -> Integer -> Ordering # (<) :: Integer -> Integer -> Bool # (<=) :: Integer -> Integer -> Bool # (>) :: Integer -> Integer -> Bool # (>=) :: Integer -> Integer -> Bool # max :: Integer -> Integer -> Integer # min :: Integer -> Integer -> Integer #
Ord Natural	Since: base-4.8.0.0
Instance details Defined in GHC.Natural Methods compare :: Natural -> Natural -> Ordering # (<) :: Natural -> Natural -> Bool # (<=) :: Natural -> Natural -> Bool # (>) :: Natural -> Natural -> Bool # (>=) :: Natural -> Natural -> Bool # max :: Natural -> Natural -> Natural # min :: Natural -> Natural -> Natural #
Ord Ordering
Instance details Defined in GHC.Classes Methods compare :: Ordering -> Ordering -> Ordering # (<) :: Ordering -> Ordering -> Bool # (<=) :: Ordering -> Ordering -> Bool # (>) :: Ordering -> Ordering -> Bool # (>=) :: Ordering -> Ordering -> Bool # max :: Ordering -> Ordering -> Ordering # min :: Ordering -> Ordering -> Ordering #
Ord Word
Instance details Defined in GHC.Classes Methods compare :: Word -> Word -> Ordering # (<) :: Word -> Word -> Bool # (<=) :: Word -> Word -> Bool # (>) :: Word -> Word -> Bool # (>=) :: Word -> Word -> Bool # max :: Word -> Word -> Word # min :: Word -> Word -> Word #
Ord Word8	Since: base-2.1
Instance details Defined in GHC.Word Methods compare :: Word8 -> Word8 -> Ordering # (<) :: Word8 -> Word8 -> Bool # (<=) :: Word8 -> Word8 -> Bool # (>) :: Word8 -> Word8 -> Bool # (>=) :: Word8 -> Word8 -> Bool # max :: Word8 -> Word8 -> Word8 # min :: Word8 -> Word8 -> Word8 #
Ord Word16	Since: base-2.1
Instance details Defined in GHC.Word Methods compare :: Word16 -> Word16 -> Ordering # (<) :: Word16 -> Word16 -> Bool # (<=) :: Word16 -> Word16 -> Bool # (>) :: Word16 -> Word16 -> Bool # (>=) :: Word16 -> Word16 -> Bool # max :: Word16 -> Word16 -> Word16 # min :: Word16 -> Word16 -> Word16 #
Ord Word32	Since: base-2.1
Instance details Defined in GHC.Word Methods compare :: Word32 -> Word32 -> Ordering # (<) :: Word32 -> Word32 -> Bool # (<=) :: Word32 -> Word32 -> Bool # (>) :: Word32 -> Word32 -> Bool # (>=) :: Word32 -> Word32 -> Bool # max :: Word32 -> Word32 -> Word32 # min :: Word32 -> Word32 -> Word32 #
Ord Word64	Since: base-2.1
Instance details Defined in GHC.Word Methods compare :: Word64 -> Word64 -> Ordering # (<) :: Word64 -> Word64 -> Bool # (<=) :: Word64 -> Word64 -> Bool # (>) :: Word64 -> Word64 -> Bool # (>=) :: Word64 -> Word64 -> Bool # max :: Word64 -> Word64 -> Word64 # min :: Word64 -> Word64 -> Word64 #
Ord SomeTypeRep
Instance details Defined in Data.Typeable.Internal Methods compare :: SomeTypeRep -> SomeTypeRep -> Ordering # (<) :: SomeTypeRep -> SomeTypeRep -> Bool # (<=) :: SomeTypeRep -> SomeTypeRep -> Bool # (>) :: SomeTypeRep -> SomeTypeRep -> Bool # (>=) :: SomeTypeRep -> SomeTypeRep -> Bool # max :: SomeTypeRep -> SomeTypeRep -> SomeTypeRep # min :: SomeTypeRep -> SomeTypeRep -> SomeTypeRep #
Ord ()
Instance details Defined in GHC.Classes Methods compare :: () -> () -> Ordering # (<) :: () -> () -> Bool # (<=) :: () -> () -> Bool # (>) :: () -> () -> Bool # (>=) :: () -> () -> Bool # max :: () -> () -> () # min :: () -> () -> () #
Ord TyCon
Instance details Defined in GHC.Classes Methods compare :: TyCon -> TyCon -> Ordering # (<) :: TyCon -> TyCon -> Bool # (<=) :: TyCon -> TyCon -> Bool # (>) :: TyCon -> TyCon -> Bool # (>=) :: TyCon -> TyCon -> Bool # max :: TyCon -> TyCon -> TyCon # min :: TyCon -> TyCon -> TyCon #
Ord BigNat
Instance details Defined in GHC.Integer.Type Methods compare :: BigNat -> BigNat -> Ordering # (<) :: BigNat -> BigNat -> Bool # (<=) :: BigNat -> BigNat -> Bool # (>) :: BigNat -> BigNat -> Bool # (>=) :: BigNat -> BigNat -> Bool # max :: BigNat -> BigNat -> BigNat # min :: BigNat -> BigNat -> BigNat #
Ord Void	Since: base-4.8.0.0
Instance details Defined in Data.Void Methods compare :: Void -> Void -> Ordering # (<) :: Void -> Void -> Bool # (<=) :: Void -> Void -> Bool # (>) :: Void -> Void -> Bool # (>=) :: Void -> Void -> Bool # max :: Void -> Void -> Void # min :: Void -> Void -> Void #
Ord Version	Since: base-2.1
Instance details Defined in Data.Version Methods compare :: Version -> Version -> Ordering # (<) :: Version -> Version -> Bool # (<=) :: Version -> Version -> Bool # (>) :: Version -> Version -> Bool # (>=) :: Version -> Version -> Bool # max :: Version -> Version -> Version # min :: Version -> Version -> Version #
Ord ThreadId	Since: base-4.2.0.0
Instance details Defined in GHC.Conc.Sync Methods compare :: ThreadId -> ThreadId -> Ordering # (<) :: ThreadId -> ThreadId -> Bool # (<=) :: ThreadId -> ThreadId -> Bool # (>) :: ThreadId -> ThreadId -> Bool # (>=) :: ThreadId -> ThreadId -> Bool # max :: ThreadId -> ThreadId -> ThreadId # min :: ThreadId -> ThreadId -> ThreadId #
Ord BlockReason	Since: base-4.3.0.0
Instance details Defined in GHC.Conc.Sync Methods compare :: BlockReason -> BlockReason -> Ordering # (<) :: BlockReason -> BlockReason -> Bool # (<=) :: BlockReason -> BlockReason -> Bool # (>) :: BlockReason -> BlockReason -> Bool # (>=) :: BlockReason -> BlockReason -> Bool # max :: BlockReason -> BlockReason -> BlockReason # min :: BlockReason -> BlockReason -> BlockReason #
Ord ThreadStatus	Since: base-4.3.0.0
Instance details Defined in GHC.Conc.Sync Methods compare :: ThreadStatus -> ThreadStatus -> Ordering # (<) :: ThreadStatus -> ThreadStatus -> Bool # (<=) :: ThreadStatus -> ThreadStatus -> Bool # (>) :: ThreadStatus -> ThreadStatus -> Bool # (>=) :: ThreadStatus -> ThreadStatus -> Bool # max :: ThreadStatus -> ThreadStatus -> ThreadStatus # min :: ThreadStatus -> ThreadStatus -> ThreadStatus #
Ord AsyncException	Since: base-4.2.0.0
Instance details Defined in GHC.IO.Exception Methods compare :: AsyncException -> AsyncException -> Ordering # (<) :: AsyncException -> AsyncException -> Bool # (<=) :: AsyncException -> AsyncException -> Bool # (>) :: AsyncException -> AsyncException -> Bool # (>=) :: AsyncException -> AsyncException -> Bool # max :: AsyncException -> AsyncException -> AsyncException # min :: AsyncException -> AsyncException -> AsyncException #
Ord ArrayException	Since: base-4.2.0.0
Instance details Defined in GHC.IO.Exception Methods compare :: ArrayException -> ArrayException -> Ordering # (<) :: ArrayException -> ArrayException -> Bool # (<=) :: ArrayException -> ArrayException -> Bool # (>) :: ArrayException -> ArrayException -> Bool # (>=) :: ArrayException -> ArrayException -> Bool # max :: ArrayException -> ArrayException -> ArrayException # min :: ArrayException -> ArrayException -> ArrayException #
Ord ExitCode
Instance details Defined in GHC.IO.Exception Methods compare :: ExitCode -> ExitCode -> Ordering # (<) :: ExitCode -> ExitCode -> Bool # (<=) :: ExitCode -> ExitCode -> Bool # (>) :: ExitCode -> ExitCode -> Bool # (>=) :: ExitCode -> ExitCode -> Bool # max :: ExitCode -> ExitCode -> ExitCode # min :: ExitCode -> ExitCode -> ExitCode #
Ord BufferMode	Since: base-4.2.0.0
Instance details Defined in GHC.IO.Handle.Types Methods compare :: BufferMode -> BufferMode -> Ordering # (<) :: BufferMode -> BufferMode -> Bool # (<=) :: BufferMode -> BufferMode -> Bool # (>) :: BufferMode -> BufferMode -> Bool # (>=) :: BufferMode -> BufferMode -> Bool # max :: BufferMode -> BufferMode -> BufferMode # min :: BufferMode -> BufferMode -> BufferMode #
Ord Newline	Since: base-4.3.0.0
Instance details Defined in GHC.IO.Handle.Types Methods compare :: Newline -> Newline -> Ordering # (<) :: Newline -> Newline -> Bool # (<=) :: Newline -> Newline -> Bool # (>) :: Newline -> Newline -> Bool # (>=) :: Newline -> Newline -> Bool # max :: Newline -> Newline -> Newline # min :: Newline -> Newline -> Newline #
Ord NewlineMode	Since: base-4.3.0.0
Instance details Defined in GHC.IO.Handle.Types Methods compare :: NewlineMode -> NewlineMode -> Ordering # (<) :: NewlineMode -> NewlineMode -> Bool # (<=) :: NewlineMode -> NewlineMode -> Bool # (>) :: NewlineMode -> NewlineMode -> Bool # (>=) :: NewlineMode -> NewlineMode -> Bool # max :: NewlineMode -> NewlineMode -> NewlineMode # min :: NewlineMode -> NewlineMode -> NewlineMode #
Ord ErrorCall	Since: base-4.7.0.0
Instance details Defined in GHC.Exception Methods compare :: ErrorCall -> ErrorCall -> Ordering # (<) :: ErrorCall -> ErrorCall -> Bool # (<=) :: ErrorCall -> ErrorCall -> Bool # (>) :: ErrorCall -> ErrorCall -> Bool # (>=) :: ErrorCall -> ErrorCall -> Bool # max :: ErrorCall -> ErrorCall -> ErrorCall # min :: ErrorCall -> ErrorCall -> ErrorCall #
Ord ArithException	Since: base-3.0
Instance details Defined in GHC.Exception.Type Methods compare :: ArithException -> ArithException -> Ordering # (<) :: ArithException -> ArithException -> Bool # (<=) :: ArithException -> ArithException -> Bool # (>) :: ArithException -> ArithException -> Bool # (>=) :: ArithException -> ArithException -> Bool # max :: ArithException -> ArithException -> ArithException # min :: ArithException -> ArithException -> ArithException #
Ord All	Since: base-2.1
Instance details Defined in Data.Semigroup.Internal Methods compare :: All -> All -> Ordering # (<) :: All -> All -> Bool # (<=) :: All -> All -> Bool # (>) :: All -> All -> Bool # (>=) :: All -> All -> Bool # max :: All -> All -> All # min :: All -> All -> All #
Ord Any	Since: base-2.1
Instance details Defined in Data.Semigroup.Internal Methods compare :: Any -> Any -> Ordering # (<) :: Any -> Any -> Bool # (<=) :: Any -> Any -> Bool # (>) :: Any -> Any -> Bool # (>=) :: Any -> Any -> Bool # max :: Any -> Any -> Any # min :: Any -> Any -> Any #
Ord Fixity	Since: base-4.6.0.0
Instance details Defined in GHC.Generics Methods compare :: Fixity -> Fixity -> Ordering # (<) :: Fixity -> Fixity -> Bool # (<=) :: Fixity -> Fixity -> Bool # (>) :: Fixity -> Fixity -> Bool # (>=) :: Fixity -> Fixity -> Bool # max :: Fixity -> Fixity -> Fixity # min :: Fixity -> Fixity -> Fixity #
Ord Associativity	Since: base-4.6.0.0
Instance details Defined in GHC.Generics Methods compare :: Associativity -> Associativity -> Ordering # (<) :: Associativity -> Associativity -> Bool # (<=) :: Associativity -> Associativity -> Bool # (>) :: Associativity -> Associativity -> Bool # (>=) :: Associativity -> Associativity -> Bool # max :: Associativity -> Associativity -> Associativity # min :: Associativity -> Associativity -> Associativity #
Ord SourceUnpackedness	Since: base-4.9.0.0
Instance details Defined in GHC.Generics Methods compare :: SourceUnpackedness -> SourceUnpackedness -> Ordering # (<) :: SourceUnpackedness -> SourceUnpackedness -> Bool # (<=) :: SourceUnpackedness -> SourceUnpackedness -> Bool # (>) :: SourceUnpackedness -> SourceUnpackedness -> Bool # (>=) :: SourceUnpackedness -> SourceUnpackedness -> Bool # max :: SourceUnpackedness -> SourceUnpackedness -> SourceUnpackedness # min :: SourceUnpackedness -> SourceUnpackedness -> SourceUnpackedness #
Ord SourceStrictness	Since: base-4.9.0.0
Instance details Defined in GHC.Generics Methods compare :: SourceStrictness -> SourceStrictness -> Ordering # (<) :: SourceStrictness -> SourceStrictness -> Bool # (<=) :: SourceStrictness -> SourceStrictness -> Bool # (>) :: SourceStrictness -> SourceStrictness -> Bool # (>=) :: SourceStrictness -> SourceStrictness -> Bool # max :: SourceStrictness -> SourceStrictness -> SourceStrictness # min :: SourceStrictness -> SourceStrictness -> SourceStrictness #
Ord DecidedStrictness	Since: base-4.9.0.0
Instance details Defined in GHC.Generics Methods compare :: DecidedStrictness -> DecidedStrictness -> Ordering # (<) :: DecidedStrictness -> DecidedStrictness -> Bool # (<=) :: DecidedStrictness -> DecidedStrictness -> Bool # (>) :: DecidedStrictness -> DecidedStrictness -> Bool # (>=) :: DecidedStrictness -> DecidedStrictness -> Bool # max :: DecidedStrictness -> DecidedStrictness -> DecidedStrictness # min :: DecidedStrictness -> DecidedStrictness -> DecidedStrictness #
Ord SomeNat	Since: base-4.7.0.0
Instance details Defined in GHC.TypeNats Methods compare :: SomeNat -> SomeNat -> Ordering # (<) :: SomeNat -> SomeNat -> Bool # (<=) :: SomeNat -> SomeNat -> Bool # (>) :: SomeNat -> SomeNat -> Bool # (>=) :: SomeNat -> SomeNat -> Bool # max :: SomeNat -> SomeNat -> SomeNat # min :: SomeNat -> SomeNat -> SomeNat #
Ord IOMode	Since: base-4.2.0.0
Instance details Defined in GHC.IO.IOMode Methods compare :: IOMode -> IOMode -> Ordering # (<) :: IOMode -> IOMode -> Bool # (<=) :: IOMode -> IOMode -> Bool # (>) :: IOMode -> IOMode -> Bool # (>=) :: IOMode -> IOMode -> Bool # max :: IOMode -> IOMode -> IOMode # min :: IOMode -> IOMode -> IOMode #
Ord ByteString
Instance details Defined in Data.ByteString.Internal Methods compare :: ByteString -> ByteString -> Ordering # (<) :: ByteString -> ByteString -> Bool # (<=) :: ByteString -> ByteString -> Bool # (>) :: ByteString -> ByteString -> Bool # (>=) :: ByteString -> ByteString -> Bool # max :: ByteString -> ByteString -> ByteString # min :: ByteString -> ByteString -> ByteString #
Ord IntSet
Instance details Defined in Data.IntSet.Internal Methods compare :: IntSet -> IntSet -> Ordering # (<) :: IntSet -> IntSet -> Bool # (<=) :: IntSet -> IntSet -> Bool # (>) :: IntSet -> IntSet -> Bool # (>=) :: IntSet -> IntSet -> Bool # max :: IntSet -> IntSet -> IntSet # min :: IntSet -> IntSet -> IntSet #
Ord Undefined
Instance details Defined in Universum.Debug Methods compare :: Undefined -> Undefined -> Ordering # (<) :: Undefined -> Undefined -> Bool # (<=) :: Undefined -> Undefined -> Bool # (>) :: Undefined -> Undefined -> Bool # (>=) :: Undefined -> Undefined -> Bool # max :: Undefined -> Undefined -> Undefined # min :: Undefined -> Undefined -> Undefined #
Ord a => Ord [a]
Instance details Defined in GHC.Classes Methods compare :: [a] -> [a] -> Ordering # (<) :: [a] -> [a] -> Bool # (<=) :: [a] -> [a] -> Bool # (>) :: [a] -> [a] -> Bool # (>=) :: [a] -> [a] -> Bool # max :: [a] -> [a] -> [a] # min :: [a] -> [a] -> [a] #
Ord a => Ord (Maybe a)	Since: base-2.1
Instance details Defined in GHC.Maybe Methods compare :: Maybe a -> Maybe a -> Ordering # (<) :: Maybe a -> Maybe a -> Bool # (<=) :: Maybe a -> Maybe a -> Bool # (>) :: Maybe a -> Maybe a -> Bool # (>=) :: Maybe a -> Maybe a -> Bool # max :: Maybe a -> Maybe a -> Maybe a # min :: Maybe a -> Maybe a -> Maybe a #
Integral a => Ord (Ratio a)	Since: base-2.0.1
Instance details Defined in GHC.Real Methods compare :: Ratio a -> Ratio a -> Ordering # (<) :: Ratio a -> Ratio a -> Bool # (<=) :: Ratio a -> Ratio a -> Bool # (>) :: Ratio a -> Ratio a -> Bool # (>=) :: Ratio a -> Ratio a -> Bool # max :: Ratio a -> Ratio a -> Ratio a # min :: Ratio a -> Ratio a -> Ratio a #
Ord (Ptr a)	Since: base-2.1
Instance details Defined in GHC.Ptr Methods compare :: Ptr a -> Ptr a -> Ordering # (<) :: Ptr a -> Ptr a -> Bool # (<=) :: Ptr a -> Ptr a -> Bool # (>) :: Ptr a -> Ptr a -> Bool # (>=) :: Ptr a -> Ptr a -> Bool # max :: Ptr a -> Ptr a -> Ptr a # min :: Ptr a -> Ptr a -> Ptr a #
Ord (FunPtr a)
Instance details Defined in GHC.Ptr Methods compare :: FunPtr a -> FunPtr a -> Ordering # (<) :: FunPtr a -> FunPtr a -> Bool # (<=) :: FunPtr a -> FunPtr a -> Bool # (>) :: FunPtr a -> FunPtr a -> Bool # (>=) :: FunPtr a -> FunPtr a -> Bool # max :: FunPtr a -> FunPtr a -> FunPtr a # min :: FunPtr a -> FunPtr a -> FunPtr a #
Ord p => Ord (Par1 p)	Since: base-4.7.0.0
Instance details Defined in GHC.Generics Methods compare :: Par1 p -> Par1 p -> Ordering # (<) :: Par1 p -> Par1 p -> Bool # (<=) :: Par1 p -> Par1 p -> Bool # (>) :: Par1 p -> Par1 p -> Bool # (>=) :: Par1 p -> Par1 p -> Bool # max :: Par1 p -> Par1 p -> Par1 p # min :: Par1 p -> Par1 p -> Par1 p #
Ord a => Ord (Min a)	Since: base-4.9.0.0
Instance details Defined in Data.Semigroup Methods compare :: Min a -> Min a -> Ordering # (<) :: Min a -> Min a -> Bool # (<=) :: Min a -> Min a -> Bool # (>) :: Min a -> Min a -> Bool # (>=) :: Min a -> Min a -> Bool # max :: Min a -> Min a -> Min a # min :: Min a -> Min a -> Min a #
Ord a => Ord (Max a)	Since: base-4.9.0.0
Instance details Defined in Data.Semigroup Methods compare :: Max a -> Max a -> Ordering # (<) :: Max a -> Max a -> Bool # (<=) :: Max a -> Max a -> Bool # (>) :: Max a -> Max a -> Bool # (>=) :: Max a -> Max a -> Bool # max :: Max a -> Max a -> Max a # min :: Max a -> Max a -> Max a #
Ord a => Ord (First a)	Since: base-4.9.0.0
Instance details Defined in Data.Semigroup Methods compare :: First a -> First a -> Ordering # (<) :: First a -> First a -> Bool # (<=) :: First a -> First a -> Bool # (>) :: First a -> First a -> Bool # (>=) :: First a -> First a -> Bool # max :: First a -> First a -> First a # min :: First a -> First a -> First a #
Ord a => Ord (Last a)	Since: base-4.9.0.0
Instance details Defined in Data.Semigroup Methods compare :: Last a -> Last a -> Ordering # (<) :: Last a -> Last a -> Bool # (<=) :: Last a -> Last a -> Bool # (>) :: Last a -> Last a -> Bool # (>=) :: Last a -> Last a -> Bool # max :: Last a -> Last a -> Last a # min :: Last a -> Last a -> Last a #
Ord m => Ord (WrappedMonoid m)	Since: base-4.9.0.0
Instance details Defined in Data.Semigroup Methods compare :: WrappedMonoid m -> WrappedMonoid m -> Ordering # (<) :: WrappedMonoid m -> WrappedMonoid m -> Bool # (<=) :: WrappedMonoid m -> WrappedMonoid m -> Bool # (>) :: WrappedMonoid m -> WrappedMonoid m -> Bool # (>=) :: WrappedMonoid m -> WrappedMonoid m -> Bool # max :: WrappedMonoid m -> WrappedMonoid m -> WrappedMonoid m # min :: WrappedMonoid m -> WrappedMonoid m -> WrappedMonoid m #
Ord a => Ord (Option a)	Since: base-4.9.0.0
Instance details Defined in Data.Semigroup Methods compare :: Option a -> Option a -> Ordering # (<) :: Option a -> Option a -> Bool # (<=) :: Option a -> Option a -> Bool # (>) :: Option a -> Option a -> Bool # (>=) :: Option a -> Option a -> Bool # max :: Option a -> Option a -> Option a # min :: Option a -> Option a -> Option a #
Ord a => Ord (ZipList a)	Since: base-4.7.0.0
Instance details Defined in Control.Applicative Methods compare :: ZipList a -> ZipList a -> Ordering # (<) :: ZipList a -> ZipList a -> Bool # (<=) :: ZipList a -> ZipList a -> Bool # (>) :: ZipList a -> ZipList a -> Bool # (>=) :: ZipList a -> ZipList a -> Bool # max :: ZipList a -> ZipList a -> ZipList a # min :: ZipList a -> ZipList a -> ZipList a #
Ord a => Ord (Identity a)	Since: base-4.8.0.0
Instance details Defined in Data.Functor.Identity Methods compare :: Identity a -> Identity a -> Ordering # (<) :: Identity a -> Identity a -> Bool # (<=) :: Identity a -> Identity a -> Bool # (>) :: Identity a -> Identity a -> Bool # (>=) :: Identity a -> Identity a -> Bool # max :: Identity a -> Identity a -> Identity a # min :: Identity a -> Identity a -> Identity a #
Ord a => Ord (First a)	Since: base-2.1
Instance details Defined in Data.Monoid Methods compare :: First a -> First a -> Ordering # (<) :: First a -> First a -> Bool # (<=) :: First a -> First a -> Bool # (>) :: First a -> First a -> Bool # (>=) :: First a -> First a -> Bool # max :: First a -> First a -> First a # min :: First a -> First a -> First a #
Ord a => Ord (Last a)	Since: base-2.1
Instance details Defined in Data.Monoid Methods compare :: Last a -> Last a -> Ordering # (<) :: Last a -> Last a -> Bool # (<=) :: Last a -> Last a -> Bool # (>) :: Last a -> Last a -> Bool # (>=) :: Last a -> Last a -> Bool # max :: Last a -> Last a -> Last a # min :: Last a -> Last a -> Last a #
Ord a => Ord (Dual a)	Since: base-2.1
Instance details Defined in Data.Semigroup.Internal Methods compare :: Dual a -> Dual a -> Ordering # (<) :: Dual a -> Dual a -> Bool # (<=) :: Dual a -> Dual a -> Bool # (>) :: Dual a -> Dual a -> Bool # (>=) :: Dual a -> Dual a -> Bool # max :: Dual a -> Dual a -> Dual a # min :: Dual a -> Dual a -> Dual a #
Ord a => Ord (Sum a)	Since: base-2.1
Instance details Defined in Data.Semigroup.Internal Methods compare :: Sum a -> Sum a -> Ordering # (<) :: Sum a -> Sum a -> Bool # (<=) :: Sum a -> Sum a -> Bool # (>) :: Sum a -> Sum a -> Bool # (>=) :: Sum a -> Sum a -> Bool # max :: Sum a -> Sum a -> Sum a # min :: Sum a -> Sum a -> Sum a #
Ord a => Ord (Product a)	Since: base-2.1
Instance details Defined in Data.Semigroup.Internal Methods compare :: Product a -> Product a -> Ordering # (<) :: Product a -> Product a -> Bool # (<=) :: Product a -> Product a -> Bool # (>) :: Product a -> Product a -> Bool # (>=) :: Product a -> Product a -> Bool # max :: Product a -> Product a -> Product a # min :: Product a -> Product a -> Product a #
Ord a => Ord (Down a)	Since: base-4.6.0.0
Instance details Defined in Data.Ord Methods compare :: Down a -> Down a -> Ordering # (<) :: Down a -> Down a -> Bool # (<=) :: Down a -> Down a -> Bool # (>) :: Down a -> Down a -> Bool # (>=) :: Down a -> Down a -> Bool # max :: Down a -> Down a -> Down a # min :: Down a -> Down a -> Down a #
Ord a => Ord (NonEmpty a)	Since: base-4.9.0.0
Instance details Defined in GHC.Base Methods compare :: NonEmpty a -> NonEmpty a -> Ordering # (<) :: NonEmpty a -> NonEmpty a -> Bool # (<=) :: NonEmpty a -> NonEmpty a -> Bool # (>) :: NonEmpty a -> NonEmpty a -> Bool # (>=) :: NonEmpty a -> NonEmpty a -> Bool # max :: NonEmpty a -> NonEmpty a -> NonEmpty a # min :: NonEmpty a -> NonEmpty a -> NonEmpty a #
Ord a => Ord (IntMap a)
Instance details Defined in Data.IntMap.Internal Methods compare :: IntMap a -> IntMap a -> Ordering # (<) :: IntMap a -> IntMap a -> Bool # (<=) :: IntMap a -> IntMap a -> Bool # (>) :: IntMap a -> IntMap a -> Bool # (>=) :: IntMap a -> IntMap a -> Bool # max :: IntMap a -> IntMap a -> IntMap a # min :: IntMap a -> IntMap a -> IntMap a #
Ord a => Ord (Seq a)
Instance details Defined in Data.Sequence.Internal Methods compare :: Seq a -> Seq a -> Ordering # (<) :: Seq a -> Seq a -> Bool # (<=) :: Seq a -> Seq a -> Bool # (>) :: Seq a -> Seq a -> Bool # (>=) :: Seq a -> Seq a -> Bool # max :: Seq a -> Seq a -> Seq a # min :: Seq a -> Seq a -> Seq a #
Ord a => Ord (ViewL a)
Instance details Defined in Data.Sequence.Internal Methods compare :: ViewL a -> ViewL a -> Ordering # (<) :: ViewL a -> ViewL a -> Bool # (<=) :: ViewL a -> ViewL a -> Bool # (>) :: ViewL a -> ViewL a -> Bool # (>=) :: ViewL a -> ViewL a -> Bool # max :: ViewL a -> ViewL a -> ViewL a # min :: ViewL a -> ViewL a -> ViewL a #
Ord a => Ord (ViewR a)
Instance details Defined in Data.Sequence.Internal Methods compare :: ViewR a -> ViewR a -> Ordering # (<) :: ViewR a -> ViewR a -> Bool # (<=) :: ViewR a -> ViewR a -> Bool # (>) :: ViewR a -> ViewR a -> Bool # (>=) :: ViewR a -> ViewR a -> Bool # max :: ViewR a -> ViewR a -> ViewR a # min :: ViewR a -> ViewR a -> ViewR a #
Ord a => Ord (Set a)
Instance details Defined in Data.Set.Internal Methods compare :: Set a -> Set a -> Ordering # (<) :: Set a -> Set a -> Bool # (<=) :: Set a -> Set a -> Bool # (>) :: Set a -> Set a -> Bool # (>=) :: Set a -> Set a -> Bool # max :: Set a -> Set a -> Set a # min :: Set a -> Set a -> Set a #
Ord a => Ord (Hashed a)
Instance details Defined in Data.Hashable.Class Methods compare :: Hashed a -> Hashed a -> Ordering # (<) :: Hashed a -> Hashed a -> Bool # (<=) :: Hashed a -> Hashed a -> Bool # (>) :: Hashed a -> Hashed a -> Bool # (>=) :: Hashed a -> Hashed a -> Bool # max :: Hashed a -> Hashed a -> Hashed a # min :: Hashed a -> Hashed a -> Hashed a #
Ord a => Ord (Vector a)
Instance details Defined in Data.Vector Methods compare :: Vector a -> Vector a -> Ordering # (<) :: Vector a -> Vector a -> Bool # (<=) :: Vector a -> Vector a -> Bool # (>) :: Vector a -> Vector a -> Bool # (>=) :: Vector a -> Vector a -> Bool # max :: Vector a -> Vector a -> Vector a # min :: Vector a -> Vector a -> Vector a #
Ord a => Ord (HashSet a)
Instance details Defined in Data.HashSet.Base Methods compare :: HashSet a -> HashSet a -> Ordering # (<) :: HashSet a -> HashSet a -> Bool # (<=) :: HashSet a -> HashSet a -> Bool # (>) :: HashSet a -> HashSet a -> Bool # (>=) :: HashSet a -> HashSet a -> Bool # max :: HashSet a -> HashSet a -> HashSet a # min :: HashSet a -> HashSet a -> HashSet a #
(Ord a, Ord b) => Ord (Either a b)	Since: base-2.1
Instance details Defined in Data.Either Methods compare :: Either a b -> Either a b -> Ordering # (<) :: Either a b -> Either a b -> Bool # (<=) :: Either a b -> Either a b -> Bool # (>) :: Either a b -> Either a b -> Bool # (>=) :: Either a b -> Either a b -> Bool # max :: Either a b -> Either a b -> Either a b # min :: Either a b -> Either a b -> Either a b #
Ord (V1 p)	Since: base-4.9.0.0
Instance details Defined in GHC.Generics Methods compare :: V1 p -> V1 p -> Ordering # (<) :: V1 p -> V1 p -> Bool # (<=) :: V1 p -> V1 p -> Bool # (>) :: V1 p -> V1 p -> Bool # (>=) :: V1 p -> V1 p -> Bool # max :: V1 p -> V1 p -> V1 p # min :: V1 p -> V1 p -> V1 p #
Ord (U1 p)	Since: base-4.7.0.0
Instance details Defined in GHC.Generics Methods compare :: U1 p -> U1 p -> Ordering # (<) :: U1 p -> U1 p -> Bool # (<=) :: U1 p -> U1 p -> Bool # (>) :: U1 p -> U1 p -> Bool # (>=) :: U1 p -> U1 p -> Bool # max :: U1 p -> U1 p -> U1 p # min :: U1 p -> U1 p -> U1 p #
Ord (TypeRep a)	Since: base-4.4.0.0
Instance details Defined in Data.Typeable.Internal Methods compare :: TypeRep a -> TypeRep a -> Ordering # (<) :: TypeRep a -> TypeRep a -> Bool # (<=) :: TypeRep a -> TypeRep a -> Bool # (>) :: TypeRep a -> TypeRep a -> Bool # (>=) :: TypeRep a -> TypeRep a -> Bool # max :: TypeRep a -> TypeRep a -> TypeRep a # min :: TypeRep a -> TypeRep a -> TypeRep a #
(Ord a, Ord b) => Ord (a, b)
Instance details Defined in GHC.Classes Methods compare :: (a, b) -> (a, b) -> Ordering # (<) :: (a, b) -> (a, b) -> Bool # (<=) :: (a, b) -> (a, b) -> Bool # (>) :: (a, b) -> (a, b) -> Bool # (>=) :: (a, b) -> (a, b) -> Bool # max :: (a, b) -> (a, b) -> (a, b) # min :: (a, b) -> (a, b) -> (a, b) #
Ord a => Ord (Arg a b)	Since: base-4.9.0.0
Instance details Defined in Data.Semigroup Methods compare :: Arg a b -> Arg a b -> Ordering # (<) :: Arg a b -> Arg a b -> Bool # (<=) :: Arg a b -> Arg a b -> Bool # (>) :: Arg a b -> Arg a b -> Bool # (>=) :: Arg a b -> Arg a b -> Bool # max :: Arg a b -> Arg a b -> Arg a b # min :: Arg a b -> Arg a b -> Arg a b #
Ord (Proxy s)	Since: base-4.7.0.0
Instance details Defined in Data.Proxy Methods compare :: Proxy s -> Proxy s -> Ordering # (<) :: Proxy s -> Proxy s -> Bool # (<=) :: Proxy s -> Proxy s -> Bool # (>) :: Proxy s -> Proxy s -> Bool # (>=) :: Proxy s -> Proxy s -> Bool # max :: Proxy s -> Proxy s -> Proxy s # min :: Proxy s -> Proxy s -> Proxy s #
(Ord k, Ord v) => Ord (Map k v)
Instance details Defined in Data.Map.Internal Methods compare :: Map k v -> Map k v -> Ordering # (<) :: Map k v -> Map k v -> Bool # (<=) :: Map k v -> Map k v -> Bool # (>) :: Map k v -> Map k v -> Bool # (>=) :: Map k v -> Map k v -> Bool # max :: Map k v -> Map k v -> Map k v # min :: Map k v -> Map k v -> Map k v #
(Ord1 m, Ord a) => Ord (MaybeT m a)
Instance details Defined in Control.Monad.Trans.Maybe Methods compare :: MaybeT m a -> MaybeT m a -> Ordering # (<) :: MaybeT m a -> MaybeT m a -> Bool # (<=) :: MaybeT m a -> MaybeT m a -> Bool # (>) :: MaybeT m a -> MaybeT m a -> Bool # (>=) :: MaybeT m a -> MaybeT m a -> Bool # max :: MaybeT m a -> MaybeT m a -> MaybeT m a # min :: MaybeT m a -> MaybeT m a -> MaybeT m a #
(Ord k, Ord v) => Ord (HashMap k v)	The order is total. Note: Because the hash is not guaranteed to be stable across library versions, OSes, or architectures, neither is an actual order of elements in `HashMap` or an result of `compare`.is stable.
Instance details Defined in Data.HashMap.Base Methods compare :: HashMap k v -> HashMap k v -> Ordering # (<) :: HashMap k v -> HashMap k v -> Bool # (<=) :: HashMap k v -> HashMap k v -> Bool # (>) :: HashMap k v -> HashMap k v -> Bool # (>=) :: HashMap k v -> HashMap k v -> Bool # max :: HashMap k v -> HashMap k v -> HashMap k v # min :: HashMap k v -> HashMap k v -> HashMap k v #
Ord (f p) => Ord (Rec1 f p)	Since: base-4.7.0.0
Instance details Defined in GHC.Generics Methods compare :: Rec1 f p -> Rec1 f p -> Ordering # (<) :: Rec1 f p -> Rec1 f p -> Bool # (<=) :: Rec1 f p -> Rec1 f p -> Bool # (>) :: Rec1 f p -> Rec1 f p -> Bool # (>=) :: Rec1 f p -> Rec1 f p -> Bool # max :: Rec1 f p -> Rec1 f p -> Rec1 f p # min :: Rec1 f p -> Rec1 f p -> Rec1 f p #
Ord (URec (Ptr ()) p)	Since: base-4.9.0.0
Instance details Defined in GHC.Generics Methods compare :: URec (Ptr ()) p -> URec (Ptr ()) p -> Ordering # (<) :: URec (Ptr ()) p -> URec (Ptr ()) p -> Bool # (<=) :: URec (Ptr ()) p -> URec (Ptr ()) p -> Bool # (>) :: URec (Ptr ()) p -> URec (Ptr ()) p -> Bool # (>=) :: URec (Ptr ()) p -> URec (Ptr ()) p -> Bool # max :: URec (Ptr ()) p -> URec (Ptr ()) p -> URec (Ptr ()) p # min :: URec (Ptr ()) p -> URec (Ptr ()) p -> URec (Ptr ()) p #
Ord (URec Char p)	Since: base-4.9.0.0
Instance details Defined in GHC.Generics Methods compare :: URec Char p -> URec Char p -> Ordering # (<) :: URec Char p -> URec Char p -> Bool # (<=) :: URec Char p -> URec Char p -> Bool # (>) :: URec Char p -> URec Char p -> Bool # (>=) :: URec Char p -> URec Char p -> Bool # max :: URec Char p -> URec Char p -> URec Char p # min :: URec Char p -> URec Char p -> URec Char p #
Ord (URec Double p)	Since: base-4.9.0.0
Instance details Defined in GHC.Generics Methods compare :: URec Double p -> URec Double p -> Ordering # (<) :: URec Double p -> URec Double p -> Bool # (<=) :: URec Double p -> URec Double p -> Bool # (>) :: URec Double p -> URec Double p -> Bool # (>=) :: URec Double p -> URec Double p -> Bool # max :: URec Double p -> URec Double p -> URec Double p # min :: URec Double p -> URec Double p -> URec Double p #
Ord (URec Float p)
Instance details Defined in GHC.Generics Methods compare :: URec Float p -> URec Float p -> Ordering # (<) :: URec Float p -> URec Float p -> Bool # (<=) :: URec Float p -> URec Float p -> Bool # (>) :: URec Float p -> URec Float p -> Bool # (>=) :: URec Float p -> URec Float p -> Bool # max :: URec Float p -> URec Float p -> URec Float p # min :: URec Float p -> URec Float p -> URec Float p #
Ord (URec Int p)	Since: base-4.9.0.0
Instance details Defined in GHC.Generics Methods compare :: URec Int p -> URec Int p -> Ordering # (<) :: URec Int p -> URec Int p -> Bool # (<=) :: URec Int p -> URec Int p -> Bool # (>) :: URec Int p -> URec Int p -> Bool # (>=) :: URec Int p -> URec Int p -> Bool # max :: URec Int p -> URec Int p -> URec Int p # min :: URec Int p -> URec Int p -> URec Int p #
Ord (URec Word p)	Since: base-4.9.0.0
Instance details Defined in GHC.Generics Methods compare :: URec Word p -> URec Word p -> Ordering # (<) :: URec Word p -> URec Word p -> Bool # (<=) :: URec Word p -> URec Word p -> Bool # (>) :: URec Word p -> URec Word p -> Bool # (>=) :: URec Word p -> URec Word p -> Bool # max :: URec Word p -> URec Word p -> URec Word p # min :: URec Word p -> URec Word p -> URec Word p #
(Ord a, Ord b, Ord c) => Ord (a, b, c)
Instance details Defined in GHC.Classes Methods compare :: (a, b, c) -> (a, b, c) -> Ordering # (<) :: (a, b, c) -> (a, b, c) -> Bool # (<=) :: (a, b, c) -> (a, b, c) -> Bool # (>) :: (a, b, c) -> (a, b, c) -> Bool # (>=) :: (a, b, c) -> (a, b, c) -> Bool # max :: (a, b, c) -> (a, b, c) -> (a, b, c) # min :: (a, b, c) -> (a, b, c) -> (a, b, c) #
Ord a => Ord (Const a b)	Since: base-4.9.0.0
Instance details Defined in Data.Functor.Const Methods compare :: Const a b -> Const a b -> Ordering # (<) :: Const a b -> Const a b -> Bool # (<=) :: Const a b -> Const a b -> Bool # (>) :: Const a b -> Const a b -> Bool # (>=) :: Const a b -> Const a b -> Bool # max :: Const a b -> Const a b -> Const a b # min :: Const a b -> Const a b -> Const a b #
Ord (f a) => Ord (Ap f a)	Since: base-4.12.0.0
Instance details Defined in Data.Monoid Methods compare :: Ap f a -> Ap f a -> Ordering # (<) :: Ap f a -> Ap f a -> Bool # (<=) :: Ap f a -> Ap f a -> Bool # (>) :: Ap f a -> Ap f a -> Bool # (>=) :: Ap f a -> Ap f a -> Bool # max :: Ap f a -> Ap f a -> Ap f a # min :: Ap f a -> Ap f a -> Ap f a #
Ord (f a) => Ord (Alt f a)	Since: base-4.8.0.0
Instance details Defined in Data.Semigroup.Internal Methods compare :: Alt f a -> Alt f a -> Ordering # (<) :: Alt f a -> Alt f a -> Bool # (<=) :: Alt f a -> Alt f a -> Bool # (>) :: Alt f a -> Alt f a -> Bool # (>=) :: Alt f a -> Alt f a -> Bool # max :: Alt f a -> Alt f a -> Alt f a # min :: Alt f a -> Alt f a -> Alt f a #
Ord (a :~: b)	Since: base-4.7.0.0
Instance details Defined in Data.Type.Equality Methods compare :: (a :~: b) -> (a :~: b) -> Ordering # (<) :: (a :~: b) -> (a :~: b) -> Bool # (<=) :: (a :~: b) -> (a :~: b) -> Bool # (>) :: (a :~: b) -> (a :~: b) -> Bool # (>=) :: (a :~: b) -> (a :~: b) -> Bool # max :: (a :~: b) -> (a :~: b) -> a :~: b # min :: (a :~: b) -> (a :~: b) -> a :~: b #
(Ord e, Ord1 m, Ord a) => Ord (ExceptT e m a)
Instance details Defined in Control.Monad.Trans.Except Methods compare :: ExceptT e m a -> ExceptT e m a -> Ordering # (<) :: ExceptT e m a -> ExceptT e m a -> Bool # (<=) :: ExceptT e m a -> ExceptT e m a -> Bool # (>) :: ExceptT e m a -> ExceptT e m a -> Bool # (>=) :: ExceptT e m a -> ExceptT e m a -> Bool # max :: ExceptT e m a -> ExceptT e m a -> ExceptT e m a # min :: ExceptT e m a -> ExceptT e m a -> ExceptT e m a #
(Ord1 f, Ord a) => Ord (IdentityT f a)
Instance details Defined in Control.Monad.Trans.Identity Methods compare :: IdentityT f a -> IdentityT f a -> Ordering # (<) :: IdentityT f a -> IdentityT f a -> Bool # (<=) :: IdentityT f a -> IdentityT f a -> Bool # (>) :: IdentityT f a -> IdentityT f a -> Bool # (>=) :: IdentityT f a -> IdentityT f a -> Bool # max :: IdentityT f a -> IdentityT f a -> IdentityT f a # min :: IdentityT f a -> IdentityT f a -> IdentityT f a #
(Ord e, Ord1 m, Ord a) => Ord (ErrorT e m a)
Instance details Defined in Control.Monad.Trans.Error Methods compare :: ErrorT e m a -> ErrorT e m a -> Ordering # (<) :: ErrorT e m a -> ErrorT e m a -> Bool # (<=) :: ErrorT e m a -> ErrorT e m a -> Bool # (>) :: ErrorT e m a -> ErrorT e m a -> Bool # (>=) :: ErrorT e m a -> ErrorT e m a -> Bool # max :: ErrorT e m a -> ErrorT e m a -> ErrorT e m a # min :: ErrorT e m a -> ErrorT e m a -> ErrorT e m a #
Ord c => Ord (K1 i c p)	Since: base-4.7.0.0
Instance details Defined in GHC.Generics Methods compare :: K1 i c p -> K1 i c p -> Ordering # (<) :: K1 i c p -> K1 i c p -> Bool # (<=) :: K1 i c p -> K1 i c p -> Bool # (>) :: K1 i c p -> K1 i c p -> Bool # (>=) :: K1 i c p -> K1 i c p -> Bool # max :: K1 i c p -> K1 i c p -> K1 i c p # min :: K1 i c p -> K1 i c p -> K1 i c p #
(Ord (f p), Ord (g p)) => Ord ((f :+: g) p)	Since: base-4.7.0.0
Instance details Defined in GHC.Generics Methods compare :: (f :+: g) p -> (f :+: g) p -> Ordering # (<) :: (f :+: g) p -> (f :+: g) p -> Bool # (<=) :: (f :+: g) p -> (f :+: g) p -> Bool # (>) :: (f :+: g) p -> (f :+: g) p -> Bool # (>=) :: (f :+: g) p -> (f :+: g) p -> Bool # max :: (f :+: g) p -> (f :+: g) p -> (f :+: g) p # min :: (f :+: g) p -> (f :+: g) p -> (f :+: g) p #
(Ord (f p), Ord (g p)) => Ord ((f :*: g) p)	Since: base-4.7.0.0
Instance details Defined in GHC.Generics Methods compare :: (f :: g) p -> (f :: g) p -> Ordering # (<) :: (f :: g) p -> (f :: g) p -> Bool # (<=) :: (f :: g) p -> (f :: g) p -> Bool # (>) :: (f :: g) p -> (f :: g) p -> Bool # (>=) :: (f :: g) p -> (f :: g) p -> Bool # max :: (f :: g) p -> (f :: g) p -> (f :: g) p # min :: (f :: g) p -> (f :: g) p -> (f :: g) p #
(Ord a, Ord b, Ord c, Ord d) => Ord (a, b, c, d)
Instance details Defined in GHC.Classes Methods compare :: (a, b, c, d) -> (a, b, c, d) -> Ordering # (<) :: (a, b, c, d) -> (a, b, c, d) -> Bool # (<=) :: (a, b, c, d) -> (a, b, c, d) -> Bool # (>) :: (a, b, c, d) -> (a, b, c, d) -> Bool # (>=) :: (a, b, c, d) -> (a, b, c, d) -> Bool # max :: (a, b, c, d) -> (a, b, c, d) -> (a, b, c, d) # min :: (a, b, c, d) -> (a, b, c, d) -> (a, b, c, d) #
Ord (a :~~: b)	Since: base-4.10.0.0
Instance details Defined in Data.Type.Equality Methods compare :: (a :~~: b) -> (a :~~: b) -> Ordering # (<) :: (a :~~: b) -> (a :~~: b) -> Bool # (<=) :: (a :~~: b) -> (a :~~: b) -> Bool # (>) :: (a :~~: b) -> (a :~~: b) -> Bool # (>=) :: (a :~~: b) -> (a :~~: b) -> Bool # max :: (a :~~: b) -> (a :~~: b) -> a :~~: b # min :: (a :~~: b) -> (a :~~: b) -> a :~~: b #
Ord (f p) => Ord (M1 i c f p)	Since: base-4.7.0.0
Instance details Defined in GHC.Generics Methods compare :: M1 i c f p -> M1 i c f p -> Ordering # (<) :: M1 i c f p -> M1 i c f p -> Bool # (<=) :: M1 i c f p -> M1 i c f p -> Bool # (>) :: M1 i c f p -> M1 i c f p -> Bool # (>=) :: M1 i c f p -> M1 i c f p -> Bool # max :: M1 i c f p -> M1 i c f p -> M1 i c f p # min :: M1 i c f p -> M1 i c f p -> M1 i c f p #
Ord (f (g p)) => Ord ((f :.: g) p)	Since: base-4.7.0.0
Instance details Defined in GHC.Generics Methods compare :: (f :.: g) p -> (f :.: g) p -> Ordering # (<) :: (f :.: g) p -> (f :.: g) p -> Bool # (<=) :: (f :.: g) p -> (f :.: g) p -> Bool # (>) :: (f :.: g) p -> (f :.: g) p -> Bool # (>=) :: (f :.: g) p -> (f :.: g) p -> Bool # max :: (f :.: g) p -> (f :.: g) p -> (f :.: g) p # min :: (f :.: g) p -> (f :.: g) p -> (f :.: g) p #
(Ord a, Ord b, Ord c, Ord d, Ord e) => Ord (a, b, c, d, e)
Instance details Defined in GHC.Classes Methods compare :: (a, b, c, d, e) -> (a, b, c, d, e) -> Ordering # (<) :: (a, b, c, d, e) -> (a, b, c, d, e) -> Bool # (<=) :: (a, b, c, d, e) -> (a, b, c, d, e) -> Bool # (>) :: (a, b, c, d, e) -> (a, b, c, d, e) -> Bool # (>=) :: (a, b, c, d, e) -> (a, b, c, d, e) -> Bool # max :: (a, b, c, d, e) -> (a, b, c, d, e) -> (a, b, c, d, e) # min :: (a, b, c, d, e) -> (a, b, c, d, e) -> (a, b, c, d, e) #
(Ord1 f, Ord1 g, Ord a) => Ord (Compose f g a)	Since: base-4.9.0.0
Instance details Defined in Data.Functor.Compose Methods compare :: Compose f g a -> Compose f g a -> Ordering # (<) :: Compose f g a -> Compose f g a -> Bool # (<=) :: Compose f g a -> Compose f g a -> Bool # (>) :: Compose f g a -> Compose f g a -> Bool # (>=) :: Compose f g a -> Compose f g a -> Bool # max :: Compose f g a -> Compose f g a -> Compose f g a # min :: Compose f g a -> Compose f g a -> Compose f g a #
(Ord a, Ord b, Ord c, Ord d, Ord e, Ord f) => Ord (a, b, c, d, e, f)
Instance details Defined in GHC.Classes Methods compare :: (a, b, c, d, e, f) -> (a, b, c, d, e, f) -> Ordering # (<) :: (a, b, c, d, e, f) -> (a, b, c, d, e, f) -> Bool # (<=) :: (a, b, c, d, e, f) -> (a, b, c, d, e, f) -> Bool # (>) :: (a, b, c, d, e, f) -> (a, b, c, d, e, f) -> Bool # (>=) :: (a, b, c, d, e, f) -> (a, b, c, d, e, f) -> Bool # max :: (a, b, c, d, e, f) -> (a, b, c, d, e, f) -> (a, b, c, d, e, f) # min :: (a, b, c, d, e, f) -> (a, b, c, d, e, f) -> (a, b, c, d, e, f) #
(Ord a, Ord b, Ord c, Ord d, Ord e, Ord f, Ord g) => Ord (a, b, c, d, e, f, g)
Instance details Defined in GHC.Classes Methods compare :: (a, b, c, d, e, f, g) -> (a, b, c, d, e, f, g) -> Ordering # (<) :: (a, b, c, d, e, f, g) -> (a, b, c, d, e, f, g) -> Bool # (<=) :: (a, b, c, d, e, f, g) -> (a, b, c, d, e, f, g) -> Bool # (>) :: (a, b, c, d, e, f, g) -> (a, b, c, d, e, f, g) -> Bool # (>=) :: (a, b, c, d, e, f, g) -> (a, b, c, d, e, f, g) -> Bool # max :: (a, b, c, d, e, f, g) -> (a, b, c, d, e, f, g) -> (a, b, c, d, e, f, g) # min :: (a, b, c, d, e, f, g) -> (a, b, c, d, e, f, g) -> (a, b, c, d, e, f, g) #
(Ord a, Ord b, Ord c, Ord d, Ord e, Ord f, Ord g, Ord h) => Ord (a, b, c, d, e, f, g, h)
Instance details Defined in GHC.Classes Methods compare :: (a, b, c, d, e, f, g, h) -> (a, b, c, d, e, f, g, h) -> Ordering # (<) :: (a, b, c, d, e, f, g, h) -> (a, b, c, d, e, f, g, h) -> Bool # (<=) :: (a, b, c, d, e, f, g, h) -> (a, b, c, d, e, f, g, h) -> Bool # (>) :: (a, b, c, d, e, f, g, h) -> (a, b, c, d, e, f, g, h) -> Bool # (>=) :: (a, b, c, d, e, f, g, h) -> (a, b, c, d, e, f, g, h) -> Bool # max :: (a, b, c, d, e, f, g, h) -> (a, b, c, d, e, f, g, h) -> (a, b, c, d, e, f, g, h) # min :: (a, b, c, d, e, f, g, h) -> (a, b, c, d, e, f, g, h) -> (a, b, c, d, e, f, g, h) #
(Ord a, Ord b, Ord c, Ord d, Ord e, Ord f, Ord g, Ord h, Ord i) => Ord (a, b, c, d, e, f, g, h, i)
Instance details Defined in GHC.Classes Methods compare :: (a, b, c, d, e, f, g, h, i) -> (a, b, c, d, e, f, g, h, i) -> Ordering # (<) :: (a, b, c, d, e, f, g, h, i) -> (a, b, c, d, e, f, g, h, i) -> Bool # (<=) :: (a, b, c, d, e, f, g, h, i) -> (a, b, c, d, e, f, g, h, i) -> Bool # (>) :: (a, b, c, d, e, f, g, h, i) -> (a, b, c, d, e, f, g, h, i) -> Bool # (>=) :: (a, b, c, d, e, f, g, h, i) -> (a, b, c, d, e, f, g, h, i) -> Bool # max :: (a, b, c, d, e, f, g, h, i) -> (a, b, c, d, e, f, g, h, i) -> (a, b, c, d, e, f, g, h, i) # min :: (a, b, c, d, e, f, g, h, i) -> (a, b, c, d, e, f, g, h, i) -> (a, b, c, d, e, f, g, h, i) #
(Ord a, Ord b, Ord c, Ord d, Ord e, Ord f, Ord g, Ord h, Ord i, Ord j) => Ord (a, b, c, d, e, f, g, h, i, j)
Instance details Defined in GHC.Classes Methods compare :: (a, b, c, d, e, f, g, h, i, j) -> (a, b, c, d, e, f, g, h, i, j) -> Ordering # (<) :: (a, b, c, d, e, f, g, h, i, j) -> (a, b, c, d, e, f, g, h, i, j) -> Bool # (<=) :: (a, b, c, d, e, f, g, h, i, j) -> (a, b, c, d, e, f, g, h, i, j) -> Bool # (>) :: (a, b, c, d, e, f, g, h, i, j) -> (a, b, c, d, e, f, g, h, i, j) -> Bool # (>=) :: (a, b, c, d, e, f, g, h, i, j) -> (a, b, c, d, e, f, g, h, i, j) -> Bool # max :: (a, b, c, d, e, f, g, h, i, j) -> (a, b, c, d, e, f, g, h, i, j) -> (a, b, c, d, e, f, g, h, i, j) # min :: (a, b, c, d, e, f, g, h, i, j) -> (a, b, c, d, e, f, g, h, i, j) -> (a, b, c, d, e, f, g, h, i, j) #
(Ord a, Ord b, Ord c, Ord d, Ord e, Ord f, Ord g, Ord h, Ord i, Ord j, Ord k) => Ord (a, b, c, d, e, f, g, h, i, j, k)
Instance details Defined in GHC.Classes Methods compare :: (a, b, c, d, e, f, g, h, i, j, k) -> (a, b, c, d, e, f, g, h, i, j, k) -> Ordering # (<) :: (a, b, c, d, e, f, g, h, i, j, k) -> (a, b, c, d, e, f, g, h, i, j, k) -> Bool # (<=) :: (a, b, c, d, e, f, g, h, i, j, k) -> (a, b, c, d, e, f, g, h, i, j, k) -> Bool # (>) :: (a, b, c, d, e, f, g, h, i, j, k) -> (a, b, c, d, e, f, g, h, i, j, k) -> Bool # (>=) :: (a, b, c, d, e, f, g, h, i, j, k) -> (a, b, c, d, e, f, g, h, i, j, k) -> Bool # max :: (a, b, c, d, e, f, g, h, i, j, k) -> (a, b, c, d, e, f, g, h, i, j, k) -> (a, b, c, d, e, f, g, h, i, j, k) # min :: (a, b, c, d, e, f, g, h, i, j, k) -> (a, b, c, d, e, f, g, h, i, j, k) -> (a, b, c, d, e, f, g, h, i, j, k) #
(Ord a, Ord b, Ord c, Ord d, Ord e, Ord f, Ord g, Ord h, Ord i, Ord j, Ord k, Ord l) => Ord (a, b, c, d, e, f, g, h, i, j, k, l)
Instance details Defined in GHC.Classes Methods compare :: (a, b, c, d, e, f, g, h, i, j, k, l) -> (a, b, c, d, e, f, g, h, i, j, k, l) -> Ordering # (<) :: (a, b, c, d, e, f, g, h, i, j, k, l) -> (a, b, c, d, e, f, g, h, i, j, k, l) -> Bool # (<=) :: (a, b, c, d, e, f, g, h, i, j, k, l) -> (a, b, c, d, e, f, g, h, i, j, k, l) -> Bool # (>) :: (a, b, c, d, e, f, g, h, i, j, k, l) -> (a, b, c, d, e, f, g, h, i, j, k, l) -> Bool # (>=) :: (a, b, c, d, e, f, g, h, i, j, k, l) -> (a, b, c, d, e, f, g, h, i, j, k, l) -> Bool # max :: (a, b, c, d, e, f, g, h, i, j, k, l) -> (a, b, c, d, e, f, g, h, i, j, k, l) -> (a, b, c, d, e, f, g, h, i, j, k, l) # min :: (a, b, c, d, e, f, g, h, i, j, k, l) -> (a, b, c, d, e, f, g, h, i, j, k, l) -> (a, b, c, d, e, f, g, h, i, j, k, l) #
(Ord a, Ord b, Ord c, Ord d, Ord e, Ord f, Ord g, Ord h, Ord i, Ord j, Ord k, Ord l, Ord m) => Ord (a, b, c, d, e, f, g, h, i, j, k, l, m)
Instance details Defined in GHC.Classes Methods compare :: (a, b, c, d, e, f, g, h, i, j, k, l, m) -> (a, b, c, d, e, f, g, h, i, j, k, l, m) -> Ordering # (<) :: (a, b, c, d, e, f, g, h, i, j, k, l, m) -> (a, b, c, d, e, f, g, h, i, j, k, l, m) -> Bool # (<=) :: (a, b, c, d, e, f, g, h, i, j, k, l, m) -> (a, b, c, d, e, f, g, h, i, j, k, l, m) -> Bool # (>) :: (a, b, c, d, e, f, g, h, i, j, k, l, m) -> (a, b, c, d, e, f, g, h, i, j, k, l, m) -> Bool # (>=) :: (a, b, c, d, e, f, g, h, i, j, k, l, m) -> (a, b, c, d, e, f, g, h, i, j, k, l, m) -> Bool # max :: (a, b, c, d, e, f, g, h, i, j, k, l, m) -> (a, b, c, d, e, f, g, h, i, j, k, l, m) -> (a, b, c, d, e, f, g, h, i, j, k, l, m) # min :: (a, b, c, d, e, f, g, h, i, j, k, l, m) -> (a, b, c, d, e, f, g, h, i, j, k, l, m) -> (a, b, c, d, e, f, g, h, i, j, k, l, m) #
(Ord a, Ord b, Ord c, Ord d, Ord e, Ord f, Ord g, Ord h, Ord i, Ord j, Ord k, Ord l, Ord m, Ord n) => Ord (a, b, c, d, e, f, g, h, i, j, k, l, m, n)
Instance details Defined in GHC.Classes Methods compare :: (a, b, c, d, e, f, g, h, i, j, k, l, m, n) -> (a, b, c, d, e, f, g, h, i, j, k, l, m, n) -> Ordering # (<) :: (a, b, c, d, e, f, g, h, i, j, k, l, m, n) -> (a, b, c, d, e, f, g, h, i, j, k, l, m, n) -> Bool # (<=) :: (a, b, c, d, e, f, g, h, i, j, k, l, m, n) -> (a, b, c, d, e, f, g, h, i, j, k, l, m, n) -> Bool # (>) :: (a, b, c, d, e, f, g, h, i, j, k, l, m, n) -> (a, b, c, d, e, f, g, h, i, j, k, l, m, n) -> Bool # (>=) :: (a, b, c, d, e, f, g, h, i, j, k, l, m, n) -> (a, b, c, d, e, f, g, h, i, j, k, l, m, n) -> Bool # max :: (a, b, c, d, e, f, g, h, i, j, k, l, m, n) -> (a, b, c, d, e, f, g, h, i, j, k, l, m, n) -> (a, b, c, d, e, f, g, h, i, j, k, l, m, n) # min :: (a, b, c, d, e, f, g, h, i, j, k, l, m, n) -> (a, b, c, d, e, f, g, h, i, j, k, l, m, n) -> (a, b, c, d, e, f, g, h, i, j, k, l, m, n) #
(Ord a, Ord b, Ord c, Ord d, Ord e, Ord f, Ord g, Ord h, Ord i, Ord j, Ord k, Ord l, Ord m, Ord n, Ord o) => Ord (a, b, c, d, e, f, g, h, i, j, k, l, m, n, o)
Instance details Defined in GHC.Classes Methods compare :: (a, b, c, d, e, f, g, h, i, j, k, l, m, n, o) -> (a, b, c, d, e, f, g, h, i, j, k, l, m, n, o) -> Ordering # (<) :: (a, b, c, d, e, f, g, h, i, j, k, l, m, n, o) -> (a, b, c, d, e, f, g, h, i, j, k, l, m, n, o) -> Bool # (<=) :: (a, b, c, d, e, f, g, h, i, j, k, l, m, n, o) -> (a, b, c, d, e, f, g, h, i, j, k, l, m, n, o) -> Bool # (>) :: (a, b, c, d, e, f, g, h, i, j, k, l, m, n, o) -> (a, b, c, d, e, f, g, h, i, j, k, l, m, n, o) -> Bool # (>=) :: (a, b, c, d, e, f, g, h, i, j, k, l, m, n, o) -> (a, b, c, d, e, f, g, h, i, j, k, l, m, n, o) -> Bool # max :: (a, b, c, d, e, f, g, h, i, j, k, l, m, n, o) -> (a, b, c, d, e, f, g, h, i, j, k, l, m, n, o) -> (a, b, c, d, e, f, g, h, i, j, k, l, m, n, o) # min :: (a, b, c, d, e, f, g, h, i, j, k, l, m, n, o) -> (a, b, c, d, e, f, g, h, i, j, k, l, m, n, o) -> (a, b, c, d, e, f, g, h, i, j, k, l, m, n, o) #

class Read a #

Parsing of Strings, producing values.

Derived instances of Read make the following assumptions, which derived instances of Show obey:

If the constructor is defined to be an infix operator, then the derived Read instance will parse only infix applications of the constructor (not the prefix form).
Associativity is not used to reduce the occurrence of parentheses, although precedence may be.
If the constructor is defined using record syntax, the derived Read will parse only the record-syntax form, and furthermore, the fields must be given in the same order as the original declaration.
The derived Read instance allows arbitrary Haskell whitespace between tokens of the input string. Extra parentheses are also allowed.

For example, given the declarations

infixr 5 :^:
data Tree a =  Leaf a  |  Tree a :^: Tree a

the derived instance of Read in Haskell 2010 is equivalent to

instance (Read a) => Read (Tree a) where

        readsPrec d r =  readParen (d > app_prec)
                         (\r -> [(Leaf m,t) |
                                 ("Leaf",s) <- lex r,
                                 (m,t) <- readsPrec (app_prec+1) s]) r

                      ++ readParen (d > up_prec)
                         (\r -> [(u:^:v,w) |
                                 (u,s) <- readsPrec (up_prec+1) r,
                                 (":^:",t) <- lex s,
                                 (v,w) <- readsPrec (up_prec+1) t]) r

          where app_prec = 10
                up_prec = 5

Note that right-associativity of :^: is unused.

The derived instance in GHC is equivalent to

instance (Read a) => Read (Tree a) where

        readPrec = parens $ (prec app_prec $ do
                                 Ident "Leaf" <- lexP
                                 m <- step readPrec
                                 return (Leaf m))

                     +++ (prec up_prec $ do
                                 u <- step readPrec
                                 Symbol ":^:" <- lexP
                                 v <- step readPrec
                                 return (u :^: v))

          where app_prec = 10
                up_prec = 5

        readListPrec = readListPrecDefault

Why do both readsPrec and readPrec exist, and why does GHC opt to implement readPrec in derived Read instances instead of readsPrec? The reason is that readsPrec is based on the ReadS type, and although ReadS is mentioned in the Haskell 2010 Report, it is not a very efficient parser data structure.

readPrec, on the other hand, is based on a much more efficient ReadPrec datatype (a.k.a "new-style parsers"), but its definition relies on the use of the RankNTypes language extension. Therefore, readPrec (and its cousin, readListPrec) are marked as GHC-only. Nevertheless, it is recommended to use readPrec instead of readsPrec whenever possible for the efficiency improvements it brings.

As mentioned above, derived Read instances in GHC will implement readPrec instead of readsPrec. The default implementations of readsPrec (and its cousin, readList) will simply use readPrec under the hood. If you are writing a Read instance by hand, it is recommended to write it like so:

instance Read T where
  readPrec     = ...
  readListPrec = readListPrecDefault

Minimal complete definition

readsPrec | readPrec

Instances

Read Bool	Since: base-2.1
Instance details Defined in GHC.Read Methods readsPrec :: Int -> ReadS Bool # readList :: ReadS [Bool] # readPrec :: ReadPrec Bool # readListPrec :: ReadPrec [Bool] #
Read Char	Since: base-2.1
Instance details Defined in GHC.Read Methods readsPrec :: Int -> ReadS Char # readList :: ReadS [Char] # readPrec :: ReadPrec Char # readListPrec :: ReadPrec [Char] #
Read Double	Since: base-2.1
Instance details Defined in GHC.Read Methods readsPrec :: Int -> ReadS Double # readList :: ReadS [Double] # readPrec :: ReadPrec Double # readListPrec :: ReadPrec [Double] #
Read Float	Since: base-2.1
Instance details Defined in GHC.Read Methods readsPrec :: Int -> ReadS Float # readList :: ReadS [Float] # readPrec :: ReadPrec Float # readListPrec :: ReadPrec [Float] #
Read Int	Since: base-2.1
Instance details Defined in GHC.Read Methods readsPrec :: Int -> ReadS Int # readList :: ReadS [Int] # readPrec :: ReadPrec Int # readListPrec :: ReadPrec [Int] #
Read Int8	Since: base-2.1
Instance details Defined in GHC.Int Methods readsPrec :: Int -> ReadS Int8 # readList :: ReadS [Int8] # readPrec :: ReadPrec Int8 # readListPrec :: ReadPrec [Int8] #
Read Int16	Since: base-2.1
Instance details Defined in GHC.Int Methods readsPrec :: Int -> ReadS Int16 # readList :: ReadS [Int16] # readPrec :: ReadPrec Int16 # readListPrec :: ReadPrec [Int16] #
Read Int32	Since: base-2.1
Instance details Defined in GHC.Int Methods readsPrec :: Int -> ReadS Int32 # readList :: ReadS [Int32] # readPrec :: ReadPrec Int32 # readListPrec :: ReadPrec [Int32] #
Read Int64	Since: base-2.1
Instance details Defined in GHC.Int Methods readsPrec :: Int -> ReadS Int64 # readList :: ReadS [Int64] # readPrec :: ReadPrec Int64 # readListPrec :: ReadPrec [Int64] #
Read Integer	Since: base-2.1
Instance details Defined in GHC.Read Methods readsPrec :: Int -> ReadS Integer # readList :: ReadS [Integer] # readPrec :: ReadPrec Integer # readListPrec :: ReadPrec [Integer] #
Read Natural	Since: base-4.8.0.0
Instance details Defined in GHC.Read Methods readsPrec :: Int -> ReadS Natural # readList :: ReadS [Natural] # readPrec :: ReadPrec Natural # readListPrec :: ReadPrec [Natural] #
Read Ordering	Since: base-2.1
Instance details Defined in GHC.Read Methods readsPrec :: Int -> ReadS Ordering # readList :: ReadS [Ordering] # readPrec :: ReadPrec Ordering # readListPrec :: ReadPrec [Ordering] #
Read Word	Since: base-4.5.0.0
Instance details Defined in GHC.Read Methods readsPrec :: Int -> ReadS Word # readList :: ReadS [Word] # readPrec :: ReadPrec Word # readListPrec :: ReadPrec [Word] #
Read Word8	Since: base-2.1
Instance details Defined in GHC.Read Methods readsPrec :: Int -> ReadS Word8 # readList :: ReadS [Word8] # readPrec :: ReadPrec Word8 # readListPrec :: ReadPrec [Word8] #
Read Word16	Since: base-2.1
Instance details Defined in GHC.Read Methods readsPrec :: Int -> ReadS Word16 # readList :: ReadS [Word16] # readPrec :: ReadPrec Word16 # readListPrec :: ReadPrec [Word16] #
Read Word32	Since: base-2.1
Instance details Defined in GHC.Read Methods readsPrec :: Int -> ReadS Word32 # readList :: ReadS [Word32] # readPrec :: ReadPrec Word32 # readListPrec :: ReadPrec [Word32] #
Read Word64	Since: base-2.1
Instance details Defined in GHC.Read Methods readsPrec :: Int -> ReadS Word64 # readList :: ReadS [Word64] # readPrec :: ReadPrec Word64 # readListPrec :: ReadPrec [Word64] #
Read ()	Since: base-2.1
Instance details Defined in GHC.Read Methods readsPrec :: Int -> ReadS () # readList :: ReadS [()] # readPrec :: ReadPrec () # readListPrec :: ReadPrec [()] #
Read Void	Reading a `Void` value is always a parse error, considering `Void` as a data type with no constructors. Since: base-4.8.0.0
Instance details Defined in Data.Void Methods readsPrec :: Int -> ReadS Void # readList :: ReadS [Void] # readPrec :: ReadPrec Void # readListPrec :: ReadPrec [Void] #
Read Version	Since: base-2.1
Instance details Defined in Data.Version Methods readsPrec :: Int -> ReadS Version # readList :: ReadS [Version] # readPrec :: ReadPrec Version # readListPrec :: ReadPrec [Version] #
Read ExitCode
Instance details Defined in GHC.IO.Exception Methods readsPrec :: Int -> ReadS ExitCode # readList :: ReadS [ExitCode] # readPrec :: ReadPrec ExitCode # readListPrec :: ReadPrec [ExitCode] #
Read BufferMode	Since: base-4.2.0.0
Instance details Defined in GHC.IO.Handle.Types Methods readsPrec :: Int -> ReadS BufferMode # readList :: ReadS [BufferMode] # readPrec :: ReadPrec BufferMode # readListPrec :: ReadPrec [BufferMode] #
Read Newline	Since: base-4.3.0.0
Instance details Defined in GHC.IO.Handle.Types Methods readsPrec :: Int -> ReadS Newline # readList :: ReadS [Newline] # readPrec :: ReadPrec Newline # readListPrec :: ReadPrec [Newline] #
Read NewlineMode	Since: base-4.3.0.0
Instance details Defined in GHC.IO.Handle.Types Methods readsPrec :: Int -> ReadS NewlineMode # readList :: ReadS [NewlineMode] # readPrec :: ReadPrec NewlineMode # readListPrec :: ReadPrec [NewlineMode] #
Read All	Since: base-2.1
Instance details Defined in Data.Semigroup.Internal Methods readsPrec :: Int -> ReadS All # readList :: ReadS [All] # readPrec :: ReadPrec All # readListPrec :: ReadPrec [All] #
Read Any	Since: base-2.1
Instance details Defined in Data.Semigroup.Internal Methods readsPrec :: Int -> ReadS Any # readList :: ReadS [Any] # readPrec :: ReadPrec Any # readListPrec :: ReadPrec [Any] #
Read Fixity	Since: base-4.6.0.0
Instance details Defined in GHC.Generics Methods readsPrec :: Int -> ReadS Fixity # readList :: ReadS [Fixity] # readPrec :: ReadPrec Fixity # readListPrec :: ReadPrec [Fixity] #
Read Associativity	Since: base-4.6.0.0
Instance details Defined in GHC.Generics Methods readsPrec :: Int -> ReadS Associativity # readList :: ReadS [Associativity] # readPrec :: ReadPrec Associativity # readListPrec :: ReadPrec [Associativity] #
Read SourceUnpackedness	Since: base-4.9.0.0
Instance details Defined in GHC.Generics Methods readsPrec :: Int -> ReadS SourceUnpackedness # readList :: ReadS [SourceUnpackedness] # readPrec :: ReadPrec SourceUnpackedness # readListPrec :: ReadPrec [SourceUnpackedness] #
Read SourceStrictness	Since: base-4.9.0.0
Instance details Defined in GHC.Generics Methods readsPrec :: Int -> ReadS SourceStrictness # readList :: ReadS [SourceStrictness] # readPrec :: ReadPrec SourceStrictness # readListPrec :: ReadPrec [SourceStrictness] #
Read DecidedStrictness	Since: base-4.9.0.0
Instance details Defined in GHC.Generics Methods readsPrec :: Int -> ReadS DecidedStrictness # readList :: ReadS [DecidedStrictness] # readPrec :: ReadPrec DecidedStrictness # readListPrec :: ReadPrec [DecidedStrictness] #
Read SomeNat	Since: base-4.7.0.0
Instance details Defined in GHC.TypeNats Methods readsPrec :: Int -> ReadS SomeNat # readList :: ReadS [SomeNat] # readPrec :: ReadPrec SomeNat # readListPrec :: ReadPrec [SomeNat] #
Read IOMode	Since: base-4.2.0.0
Instance details Defined in GHC.IO.IOMode Methods readsPrec :: Int -> ReadS IOMode # readList :: ReadS [IOMode] # readPrec :: ReadPrec IOMode # readListPrec :: ReadPrec [IOMode] #
Read Lexeme	Since: base-2.1
Instance details Defined in GHC.Read Methods readsPrec :: Int -> ReadS Lexeme # readList :: ReadS [Lexeme] # readPrec :: ReadPrec Lexeme # readListPrec :: ReadPrec [Lexeme] #
Read GeneralCategory	Since: base-2.1
Instance details Defined in GHC.Read Methods readsPrec :: Int -> ReadS GeneralCategory # readList :: ReadS [GeneralCategory] # readPrec :: ReadPrec GeneralCategory # readListPrec :: ReadPrec [GeneralCategory] #
Read ByteString
Instance details Defined in Data.ByteString.Internal Methods readsPrec :: Int -> ReadS ByteString # readList :: ReadS [ByteString] # readPrec :: ReadPrec ByteString # readListPrec :: ReadPrec [ByteString] #
Read IntSet
Instance details Defined in Data.IntSet.Internal Methods readsPrec :: Int -> ReadS IntSet # readList :: ReadS [IntSet] # readPrec :: ReadPrec IntSet # readListPrec :: ReadPrec [IntSet] #
Read Undefined
Instance details Defined in Universum.Debug Methods readsPrec :: Int -> ReadS Undefined # readList :: ReadS [Undefined] # readPrec :: ReadPrec Undefined # readListPrec :: ReadPrec [Undefined] #
Read a => Read [a]	Since: base-2.1
Instance details Defined in GHC.Read Methods readsPrec :: Int -> ReadS [a] # readList :: ReadS [[a]] # readPrec :: ReadPrec [a] # readListPrec :: ReadPrec [[a]] #
Read a => Read (Maybe a)	Since: base-2.1
Instance details Defined in GHC.Read Methods readsPrec :: Int -> ReadS (Maybe a) # readList :: ReadS [Maybe a] # readPrec :: ReadPrec (Maybe a) # readListPrec :: ReadPrec [Maybe a] #
(Integral a, Read a) => Read (Ratio a)	Since: base-2.1
Instance details Defined in GHC.Read Methods readsPrec :: Int -> ReadS (Ratio a) # readList :: ReadS [Ratio a] # readPrec :: ReadPrec (Ratio a) # readListPrec :: ReadPrec [Ratio a] #
Read p => Read (Par1 p)	Since: base-4.7.0.0
Instance details Defined in GHC.Generics Methods readsPrec :: Int -> ReadS (Par1 p) # readList :: ReadS [Par1 p] # readPrec :: ReadPrec (Par1 p) # readListPrec :: ReadPrec [Par1 p] #
Read a => Read (Min a)	Since: base-4.9.0.0
Instance details Defined in Data.Semigroup Methods readsPrec :: Int -> ReadS (Min a) # readList :: ReadS [Min a] # readPrec :: ReadPrec (Min a) # readListPrec :: ReadPrec [Min a] #
Read a => Read (Max a)	Since: base-4.9.0.0
Instance details Defined in Data.Semigroup Methods readsPrec :: Int -> ReadS (Max a) # readList :: ReadS [Max a] # readPrec :: ReadPrec (Max a) # readListPrec :: ReadPrec [Max a] #
Read a => Read (First a)	Since: base-4.9.0.0
Instance details Defined in Data.Semigroup Methods readsPrec :: Int -> ReadS (First a) # readList :: ReadS [First a] # readPrec :: ReadPrec (First a) # readListPrec :: ReadPrec [First a] #
Read a => Read (Last a)	Since: base-4.9.0.0
Instance details Defined in Data.Semigroup Methods readsPrec :: Int -> ReadS (Last a) # readList :: ReadS [Last a] # readPrec :: ReadPrec (Last a) # readListPrec :: ReadPrec [Last a] #
Read m => Read (WrappedMonoid m)	Since: base-4.9.0.0
Instance details Defined in Data.Semigroup Methods readsPrec :: Int -> ReadS (WrappedMonoid m) # readList :: ReadS [WrappedMonoid m] # readPrec :: ReadPrec (WrappedMonoid m) # readListPrec :: ReadPrec [WrappedMonoid m] #
Read a => Read (Option a)	Since: base-4.9.0.0
Instance details Defined in Data.Semigroup Methods readsPrec :: Int -> ReadS (Option a) # readList :: ReadS [Option a] # readPrec :: ReadPrec (Option a) # readListPrec :: ReadPrec [Option a] #
Read a => Read (ZipList a)	Since: base-4.7.0.0
Instance details Defined in Control.Applicative Methods readsPrec :: Int -> ReadS (ZipList a) # readList :: ReadS [ZipList a] # readPrec :: ReadPrec (ZipList a) # readListPrec :: ReadPrec [ZipList a] #
Read a => Read (Identity a)	This instance would be equivalent to the derived instances of the `Identity` newtype if the `runIdentity` field were removed Since: base-4.8.0.0
Instance details Defined in Data.Functor.Identity Methods readsPrec :: Int -> ReadS (Identity a) # readList :: ReadS [Identity a] # readPrec :: ReadPrec (Identity a) # readListPrec :: ReadPrec [Identity a] #
Read a => Read (First a)	Since: base-2.1
Instance details Defined in Data.Monoid Methods readsPrec :: Int -> ReadS (First a) # readList :: ReadS [First a] # readPrec :: ReadPrec (First a) # readListPrec :: ReadPrec [First a] #
Read a => Read (Last a)	Since: base-2.1
Instance details Defined in Data.Monoid Methods readsPrec :: Int -> ReadS (Last a) # readList :: ReadS [Last a] # readPrec :: ReadPrec (Last a) # readListPrec :: ReadPrec [Last a] #
Read a => Read (Dual a)	Since: base-2.1
Instance details Defined in Data.Semigroup.Internal Methods readsPrec :: Int -> ReadS (Dual a) # readList :: ReadS [Dual a] # readPrec :: ReadPrec (Dual a) # readListPrec :: ReadPrec [Dual a] #
Read a => Read (Sum a)	Since: base-2.1
Instance details Defined in Data.Semigroup.Internal Methods readsPrec :: Int -> ReadS (Sum a) # readList :: ReadS [Sum a] # readPrec :: ReadPrec (Sum a) # readListPrec :: ReadPrec [Sum a] #
Read a => Read (Product a)	Since: base-2.1
Instance details Defined in Data.Semigroup.Internal Methods readsPrec :: Int -> ReadS (Product a) # readList :: ReadS [Product a] # readPrec :: ReadPrec (Product a) # readListPrec :: ReadPrec [Product a] #
Read a => Read (Down a)	Since: base-4.7.0.0
Instance details Defined in Data.Ord Methods readsPrec :: Int -> ReadS (Down a) # readList :: ReadS [Down a] # readPrec :: ReadPrec (Down a) # readListPrec :: ReadPrec [Down a] #
Read a => Read (NonEmpty a)	Since: base-4.11.0.0
Instance details Defined in GHC.Read Methods readsPrec :: Int -> ReadS (NonEmpty a) # readList :: ReadS [NonEmpty a] # readPrec :: ReadPrec (NonEmpty a) # readListPrec :: ReadPrec [NonEmpty a] #
Read e => Read (IntMap e)
Instance details Defined in Data.IntMap.Internal Methods readsPrec :: Int -> ReadS (IntMap e) # readList :: ReadS [IntMap e] # readPrec :: ReadPrec (IntMap e) # readListPrec :: ReadPrec [IntMap e] #
Read a => Read (Seq a)
Instance details Defined in Data.Sequence.Internal Methods readsPrec :: Int -> ReadS (Seq a) # readList :: ReadS [Seq a] # readPrec :: ReadPrec (Seq a) # readListPrec :: ReadPrec [Seq a] #
Read a => Read (ViewL a)
Instance details Defined in Data.Sequence.Internal Methods readsPrec :: Int -> ReadS (ViewL a) # readList :: ReadS [ViewL a] # readPrec :: ReadPrec (ViewL a) # readListPrec :: ReadPrec [ViewL a] #
Read a => Read (ViewR a)
Instance details Defined in Data.Sequence.Internal Methods readsPrec :: Int -> ReadS (ViewR a) # readList :: ReadS [ViewR a] # readPrec :: ReadPrec (ViewR a) # readListPrec :: ReadPrec [ViewR a] #
(Read a, Ord a) => Read (Set a)
Instance details Defined in Data.Set.Internal Methods readsPrec :: Int -> ReadS (Set a) # readList :: ReadS [Set a] # readPrec :: ReadPrec (Set a) # readListPrec :: ReadPrec [Set a] #
Read a => Read (Vector a)
Instance details Defined in Data.Vector Methods readsPrec :: Int -> ReadS (Vector a) # readList :: ReadS [Vector a] # readPrec :: ReadPrec (Vector a) # readListPrec :: ReadPrec [Vector a] #
(Eq a, Hashable a, Read a) => Read (HashSet a)
Instance details Defined in Data.HashSet.Base Methods readsPrec :: Int -> ReadS (HashSet a) # readList :: ReadS [HashSet a] # readPrec :: ReadPrec (HashSet a) # readListPrec :: ReadPrec [HashSet a] #
(Read a, Read b) => Read (Either a b)	Since: base-3.0
Instance details Defined in Data.Either Methods readsPrec :: Int -> ReadS (Either a b) # readList :: ReadS [Either a b] # readPrec :: ReadPrec (Either a b) # readListPrec :: ReadPrec [Either a b] #
Read (V1 p)	Since: base-4.9.0.0
Instance details Defined in GHC.Generics Methods readsPrec :: Int -> ReadS (V1 p) # readList :: ReadS [V1 p] # readPrec :: ReadPrec (V1 p) # readListPrec :: ReadPrec [V1 p] #
Read (U1 p)	Since: base-4.9.0.0
Instance details Defined in GHC.Generics Methods readsPrec :: Int -> ReadS (U1 p) # readList :: ReadS [U1 p] # readPrec :: ReadPrec (U1 p) # readListPrec :: ReadPrec [U1 p] #
(Read a, Read b) => Read (a, b)	Since: base-2.1
Instance details Defined in GHC.Read Methods readsPrec :: Int -> ReadS (a, b) # readList :: ReadS [(a, b)] # readPrec :: ReadPrec (a, b) # readListPrec :: ReadPrec [(a, b)] #
(Ix a, Read a, Read b) => Read (Array a b)	Since: base-2.1
Instance details Defined in GHC.Read Methods readsPrec :: Int -> ReadS (Array a b) # readList :: ReadS [Array a b] # readPrec :: ReadPrec (Array a b) # readListPrec :: ReadPrec [Array a b] #
(Read a, Read b) => Read (Arg a b)	Since: base-4.9.0.0
Instance details Defined in Data.Semigroup Methods readsPrec :: Int -> ReadS (Arg a b) # readList :: ReadS [Arg a b] # readPrec :: ReadPrec (Arg a b) # readListPrec :: ReadPrec [Arg a b] #
Read (Proxy t)	Since: base-4.7.0.0
Instance details Defined in Data.Proxy Methods readsPrec :: Int -> ReadS (Proxy t) # readList :: ReadS [Proxy t] # readPrec :: ReadPrec (Proxy t) # readListPrec :: ReadPrec [Proxy t] #
(Ord k, Read k, Read e) => Read (Map k e)
Instance details Defined in Data.Map.Internal Methods readsPrec :: Int -> ReadS (Map k e) # readList :: ReadS [Map k e] # readPrec :: ReadPrec (Map k e) # readListPrec :: ReadPrec [Map k e] #
(Read1 m, Read a) => Read (MaybeT m a)
Instance details Defined in Control.Monad.Trans.Maybe Methods readsPrec :: Int -> ReadS (MaybeT m a) # readList :: ReadS [MaybeT m a] # readPrec :: ReadPrec (MaybeT m a) # readListPrec :: ReadPrec [MaybeT m a] #
(Eq k, Hashable k, Read k, Read e) => Read (HashMap k e)
Instance details Defined in Data.HashMap.Base Methods readsPrec :: Int -> ReadS (HashMap k e) # readList :: ReadS [HashMap k e] # readPrec :: ReadPrec (HashMap k e) # readListPrec :: ReadPrec [HashMap k e] #
Read (f p) => Read (Rec1 f p)	Since: base-4.7.0.0
Instance details Defined in GHC.Generics Methods readsPrec :: Int -> ReadS (Rec1 f p) # readList :: ReadS [Rec1 f p] # readPrec :: ReadPrec (Rec1 f p) # readListPrec :: ReadPrec [Rec1 f p] #
(Read a, Read b, Read c) => Read (a, b, c)	Since: base-2.1
Instance details Defined in GHC.Read Methods readsPrec :: Int -> ReadS (a, b, c) # readList :: ReadS [(a, b, c)] # readPrec :: ReadPrec (a, b, c) # readListPrec :: ReadPrec [(a, b, c)] #
Read a => Read (Const a b)	This instance would be equivalent to the derived instances of the `Const` newtype if the `runConst` field were removed Since: base-4.8.0.0
Instance details Defined in Data.Functor.Const Methods readsPrec :: Int -> ReadS (Const a b) # readList :: ReadS [Const a b] # readPrec :: ReadPrec (Const a b) # readListPrec :: ReadPrec [Const a b] #
Read (f a) => Read (Ap f a)	Since: base-4.12.0.0
Instance details Defined in Data.Monoid Methods readsPrec :: Int -> ReadS (Ap f a) # readList :: ReadS [Ap f a] # readPrec :: ReadPrec (Ap f a) # readListPrec :: ReadPrec [Ap f a] #
Read (f a) => Read (Alt f a)	Since: base-4.8.0.0
Instance details Defined in Data.Semigroup.Internal Methods readsPrec :: Int -> ReadS (Alt f a) # readList :: ReadS [Alt f a] # readPrec :: ReadPrec (Alt f a) # readListPrec :: ReadPrec [Alt f a] #
a ~ b => Read (a :~: b)	Since: base-4.7.0.0
Instance details Defined in Data.Type.Equality Methods readsPrec :: Int -> ReadS (a :~: b) # readList :: ReadS [a :~: b] # readPrec :: ReadPrec (a :~: b) # readListPrec :: ReadPrec [a :~: b] #
(Read e, Read1 m, Read a) => Read (ExceptT e m a)
Instance details Defined in Control.Monad.Trans.Except Methods readsPrec :: Int -> ReadS (ExceptT e m a) # readList :: ReadS [ExceptT e m a] # readPrec :: ReadPrec (ExceptT e m a) # readListPrec :: ReadPrec [ExceptT e m a] #
(Read1 f, Read a) => Read (IdentityT f a)
Instance details Defined in Control.Monad.Trans.Identity Methods readsPrec :: Int -> ReadS (IdentityT f a) # readList :: ReadS [IdentityT f a] # readPrec :: ReadPrec (IdentityT f a) # readListPrec :: ReadPrec [IdentityT f a] #
(Read e, Read1 m, Read a) => Read (ErrorT e m a)
Instance details Defined in Control.Monad.Trans.Error Methods readsPrec :: Int -> ReadS (ErrorT e m a) # readList :: ReadS [ErrorT e m a] # readPrec :: ReadPrec (ErrorT e m a) # readListPrec :: ReadPrec [ErrorT e m a] #
Read c => Read (K1 i c p)	Since: base-4.7.0.0
Instance details Defined in GHC.Generics Methods readsPrec :: Int -> ReadS (K1 i c p) # readList :: ReadS [K1 i c p] # readPrec :: ReadPrec (K1 i c p) # readListPrec :: ReadPrec [K1 i c p] #
(Read (f p), Read (g p)) => Read ((f :+: g) p)	Since: base-4.7.0.0
Instance details Defined in GHC.Generics Methods readsPrec :: Int -> ReadS ((f :+: g) p) # readList :: ReadS [(f :+: g) p] # readPrec :: ReadPrec ((f :+: g) p) # readListPrec :: ReadPrec [(f :+: g) p] #
(Read (f p), Read (g p)) => Read ((f :*: g) p)	Since: base-4.7.0.0
Instance details Defined in GHC.Generics Methods readsPrec :: Int -> ReadS ((f :: g) p) # readList :: ReadS [(f :: g) p] # readPrec :: ReadPrec ((f :: g) p) # readListPrec :: ReadPrec [(f :: g) p] #
(Read a, Read b, Read c, Read d) => Read (a, b, c, d)	Since: base-2.1
Instance details Defined in GHC.Read Methods readsPrec :: Int -> ReadS (a, b, c, d) # readList :: ReadS [(a, b, c, d)] # readPrec :: ReadPrec (a, b, c, d) # readListPrec :: ReadPrec [(a, b, c, d)] #
a ~~ b => Read (a :~~: b)	Since: base-4.10.0.0
Instance details Defined in Data.Type.Equality Methods readsPrec :: Int -> ReadS (a :~~: b) # readList :: ReadS [a :~~: b] # readPrec :: ReadPrec (a :~~: b) # readListPrec :: ReadPrec [a :~~: b] #
Read (f p) => Read (M1 i c f p)	Since: base-4.7.0.0
Instance details Defined in GHC.Generics Methods readsPrec :: Int -> ReadS (M1 i c f p) # readList :: ReadS [M1 i c f p] # readPrec :: ReadPrec (M1 i c f p) # readListPrec :: ReadPrec [M1 i c f p] #
Read (f (g p)) => Read ((f :.: g) p)	Since: base-4.7.0.0
Instance details Defined in GHC.Generics Methods readsPrec :: Int -> ReadS ((f :.: g) p) # readList :: ReadS [(f :.: g) p] # readPrec :: ReadPrec ((f :.: g) p) # readListPrec :: ReadPrec [(f :.: g) p] #
(Read a, Read b, Read c, Read d, Read e) => Read (a, b, c, d, e)	Since: base-2.1
Instance details Defined in GHC.Read Methods readsPrec :: Int -> ReadS (a, b, c, d, e) # readList :: ReadS [(a, b, c, d, e)] # readPrec :: ReadPrec (a, b, c, d, e) # readListPrec :: ReadPrec [(a, b, c, d, e)] #
(Read1 f, Read1 g, Read a) => Read (Compose f g a)	Since: base-4.9.0.0
Instance details Defined in Data.Functor.Compose Methods readsPrec :: Int -> ReadS (Compose f g a) # readList :: ReadS [Compose f g a] # readPrec :: ReadPrec (Compose f g a) # readListPrec :: ReadPrec [Compose f g a] #
(Read a, Read b, Read c, Read d, Read e, Read f) => Read (a, b, c, d, e, f)	Since: base-2.1
Instance details Defined in GHC.Read Methods readsPrec :: Int -> ReadS (a, b, c, d, e, f) # readList :: ReadS [(a, b, c, d, e, f)] # readPrec :: ReadPrec (a, b, c, d, e, f) # readListPrec :: ReadPrec [(a, b, c, d, e, f)] #
(Read a, Read b, Read c, Read d, Read e, Read f, Read g) => Read (a, b, c, d, e, f, g)	Since: base-2.1
Instance details Defined in GHC.Read Methods readsPrec :: Int -> ReadS (a, b, c, d, e, f, g) # readList :: ReadS [(a, b, c, d, e, f, g)] # readPrec :: ReadPrec (a, b, c, d, e, f, g) # readListPrec :: ReadPrec [(a, b, c, d, e, f, g)] #
(Read a, Read b, Read c, Read d, Read e, Read f, Read g, Read h) => Read (a, b, c, d, e, f, g, h)	Since: base-2.1
Instance details Defined in GHC.Read Methods readsPrec :: Int -> ReadS (a, b, c, d, e, f, g, h) # readList :: ReadS [(a, b, c, d, e, f, g, h)] # readPrec :: ReadPrec (a, b, c, d, e, f, g, h) # readListPrec :: ReadPrec [(a, b, c, d, e, f, g, h)] #
(Read a, Read b, Read c, Read d, Read e, Read f, Read g, Read h, Read i) => Read (a, b, c, d, e, f, g, h, i)	Since: base-2.1
Instance details Defined in GHC.Read Methods readsPrec :: Int -> ReadS (a, b, c, d, e, f, g, h, i) # readList :: ReadS [(a, b, c, d, e, f, g, h, i)] # readPrec :: ReadPrec (a, b, c, d, e, f, g, h, i) # readListPrec :: ReadPrec [(a, b, c, d, e, f, g, h, i)] #
(Read a, Read b, Read c, Read d, Read e, Read f, Read g, Read h, Read i, Read j) => Read (a, b, c, d, e, f, g, h, i, j)	Since: base-2.1
Instance details Defined in GHC.Read Methods readsPrec :: Int -> ReadS (a, b, c, d, e, f, g, h, i, j) # readList :: ReadS [(a, b, c, d, e, f, g, h, i, j)] # readPrec :: ReadPrec (a, b, c, d, e, f, g, h, i, j) # readListPrec :: ReadPrec [(a, b, c, d, e, f, g, h, i, j)] #
(Read a, Read b, Read c, Read d, Read e, Read f, Read g, Read h, Read i, Read j, Read k) => Read (a, b, c, d, e, f, g, h, i, j, k)	Since: base-2.1
Instance details Defined in GHC.Read Methods readsPrec :: Int -> ReadS (a, b, c, d, e, f, g, h, i, j, k) # readList :: ReadS [(a, b, c, d, e, f, g, h, i, j, k)] # readPrec :: ReadPrec (a, b, c, d, e, f, g, h, i, j, k) # readListPrec :: ReadPrec [(a, b, c, d, e, f, g, h, i, j, k)] #
(Read a, Read b, Read c, Read d, Read e, Read f, Read g, Read h, Read i, Read j, Read k, Read l) => Read (a, b, c, d, e, f, g, h, i, j, k, l)	Since: base-2.1
Instance details Defined in GHC.Read Methods readsPrec :: Int -> ReadS (a, b, c, d, e, f, g, h, i, j, k, l) # readList :: ReadS [(a, b, c, d, e, f, g, h, i, j, k, l)] # readPrec :: ReadPrec (a, b, c, d, e, f, g, h, i, j, k, l) # readListPrec :: ReadPrec [(a, b, c, d, e, f, g, h, i, j, k, l)] #
(Read a, Read b, Read c, Read d, Read e, Read f, Read g, Read h, Read i, Read j, Read k, Read l, Read m) => Read (a, b, c, d, e, f, g, h, i, j, k, l, m)	Since: base-2.1
Instance details Defined in GHC.Read Methods readsPrec :: Int -> ReadS (a, b, c, d, e, f, g, h, i, j, k, l, m) # readList :: ReadS [(a, b, c, d, e, f, g, h, i, j, k, l, m)] # readPrec :: ReadPrec (a, b, c, d, e, f, g, h, i, j, k, l, m) # readListPrec :: ReadPrec [(a, b, c, d, e, f, g, h, i, j, k, l, m)] #
(Read a, Read b, Read c, Read d, Read e, Read f, Read g, Read h, Read i, Read j, Read k, Read l, Read m, Read n) => Read (a, b, c, d, e, f, g, h, i, j, k, l, m, n)	Since: base-2.1
Instance details Defined in GHC.Read Methods readsPrec :: Int -> ReadS (a, b, c, d, e, f, g, h, i, j, k, l, m, n) # readList :: ReadS [(a, b, c, d, e, f, g, h, i, j, k, l, m, n)] # readPrec :: ReadPrec (a, b, c, d, e, f, g, h, i, j, k, l, m, n) # readListPrec :: ReadPrec [(a, b, c, d, e, f, g, h, i, j, k, l, m, n)] #
(Read a, Read b, Read c, Read d, Read e, Read f, Read g, Read h, Read i, Read j, Read k, Read l, Read m, Read n, Read o) => Read (a, b, c, d, e, f, g, h, i, j, k, l, m, n, o)	Since: base-2.1
Instance details Defined in GHC.Read Methods readsPrec :: Int -> ReadS (a, b, c, d, e, f, g, h, i, j, k, l, m, n, o) # readList :: ReadS [(a, b, c, d, e, f, g, h, i, j, k, l, m, n, o)] # readPrec :: ReadPrec (a, b, c, d, e, f, g, h, i, j, k, l, m, n, o) # readListPrec :: ReadPrec [(a, b, c, d, e, f, g, h, i, j, k, l, m, n, o)] #

class (Num a, Ord a) => Real a where #

Methods

toRational :: a -> Rational #

the rational equivalent of its real argument with full precision

Instances

Real Int	Since: base-2.0.1
Instance details Defined in GHC.Real Methods toRational :: Int -> Rational #
Real Int8	Since: base-2.1
Instance details Defined in GHC.Int Methods toRational :: Int8 -> Rational #
Real Int16	Since: base-2.1
Instance details Defined in GHC.Int Methods toRational :: Int16 -> Rational #
Real Int32	Since: base-2.1
Instance details Defined in GHC.Int Methods toRational :: Int32 -> Rational #
Real Int64	Since: base-2.1
Instance details Defined in GHC.Int Methods toRational :: Int64 -> Rational #
Real Integer	Since: base-2.0.1
Instance details Defined in GHC.Real Methods toRational :: Integer -> Rational #
Real Natural	Since: base-4.8.0.0
Instance details Defined in GHC.Real Methods toRational :: Natural -> Rational #
Real Word	Since: base-2.1
Instance details Defined in GHC.Real Methods toRational :: Word -> Rational #
Real Word8	Since: base-2.1
Instance details Defined in GHC.Word Methods toRational :: Word8 -> Rational #
Real Word16	Since: base-2.1
Instance details Defined in GHC.Word Methods toRational :: Word16 -> Rational #
Real Word32	Since: base-2.1
Instance details Defined in GHC.Word Methods toRational :: Word32 -> Rational #
Real Word64	Since: base-2.1
Instance details Defined in GHC.Word Methods toRational :: Word64 -> Rational #
Integral a => Real (Ratio a)	Since: base-2.0.1
Instance details Defined in GHC.Real Methods toRational :: Ratio a -> Rational #
Real a => Real (Identity a)	Since: base-4.9.0.0
Instance details Defined in Data.Functor.Identity Methods toRational :: Identity a -> Rational #
Real a => Real (Const a b)	Since: base-4.9.0.0
Instance details Defined in Data.Functor.Const Methods toRational :: Const a b -> Rational #

class (Real a, Fractional a) => RealFrac a where #

Extracting components of fractions.

Minimal complete definition

properFraction

Methods

properFraction :: Integral b => a -> (b, a) #

The function properFraction takes a real fractional number x and returns a pair (n,f) such that x = n+f, and:

n is an integral number with the same sign as x; and
f is a fraction with the same type and sign as x, and with absolute value less than 1.

The default definitions of the ceiling, floor, truncate and round functions are in terms of properFraction.

truncate :: Integral b => a -> b #

truncate x returns the integer nearest x between zero and x

round :: Integral b => a -> b #

round x returns the nearest integer to x; the even integer if x is equidistant between two integers

ceiling :: Integral b => a -> b #

ceiling x returns the least integer not less than x

floor :: Integral b => a -> b #

floor x returns the greatest integer not greater than x

Instances

Integral a => RealFrac (Ratio a)	Since: base-2.0.1
Instance details Defined in GHC.Real Methods properFraction :: Integral b => Ratio a -> (b, Ratio a) # truncate :: Integral b => Ratio a -> b # round :: Integral b => Ratio a -> b # ceiling :: Integral b => Ratio a -> b # floor :: Integral b => Ratio a -> b #
RealFrac a => RealFrac (Identity a)	Since: base-4.9.0.0
Instance details Defined in Data.Functor.Identity Methods properFraction :: Integral b => Identity a -> (b, Identity a) # truncate :: Integral b => Identity a -> b # round :: Integral b => Identity a -> b # ceiling :: Integral b => Identity a -> b # floor :: Integral b => Identity a -> b #
RealFrac a => RealFrac (Const a b)	Since: base-4.9.0.0
Instance details Defined in Data.Functor.Const Methods properFraction :: Integral b0 => Const a b -> (b0, Const a b) # truncate :: Integral b0 => Const a b -> b0 # round :: Integral b0 => Const a b -> b0 # ceiling :: Integral b0 => Const a b -> b0 # floor :: Integral b0 => Const a b -> b0 #

class Show a #

Conversion of values to readable Strings.

Derived instances of Show have the following properties, which are compatible with derived instances of Read:

The result of show is a syntactically correct Haskell expression containing only constants, given the fixity declarations in force at the point where the type is declared. It contains only the constructor names defined in the data type, parentheses, and spaces. When labelled constructor fields are used, braces, commas, field names, and equal signs are also used.
If the constructor is defined to be an infix operator, then showsPrec will produce infix applications of the constructor.
the representation will be enclosed in parentheses if the precedence of the top-level constructor in x is less than d (associativity is ignored). Thus, if d is 0 then the result is never surrounded in parentheses; if d is 11 it is always surrounded in parentheses, unless it is an atomic expression.
If the constructor is defined using record syntax, then show will produce the record-syntax form, with the fields given in the same order as the original declaration.

For example, given the declarations

infixr 5 :^:
data Tree a =  Leaf a  |  Tree a :^: Tree a

the derived instance of Show is equivalent to

instance (Show a) => Show (Tree a) where

       showsPrec d (Leaf m) = showParen (d > app_prec) $
            showString "Leaf " . showsPrec (app_prec+1) m
         where app_prec = 10

       showsPrec d (u :^: v) = showParen (d > up_prec) $
            showsPrec (up_prec+1) u .
            showString " :^: "      .
            showsPrec (up_prec+1) v
         where up_prec = 5

Note that right-associativity of :^: is ignored. For example,

show (Leaf 1 :^: Leaf 2 :^: Leaf 3) produces the string "Leaf 1 :^: (Leaf 2 :^: Leaf 3)".

Minimal complete definition

showsPrec | show

Instances

Show Bool	Since: base-2.1
Instance details Defined in GHC.Show Methods showsPrec :: Int -> Bool -> ShowS # show :: Bool -> String # showList :: [Bool] -> ShowS #
Show Char	Since: base-2.1
Instance details Defined in GHC.Show Methods showsPrec :: Int -> Char -> ShowS # show :: Char -> String # showList :: [Char] -> ShowS #
Show Int	Since: base-2.1
Instance details Defined in GHC.Show Methods showsPrec :: Int -> Int -> ShowS # show :: Int -> String # showList :: [Int] -> ShowS #
Show Int8	Since: base-2.1
Instance details Defined in GHC.Int Methods showsPrec :: Int -> Int8 -> ShowS # show :: Int8 -> String # showList :: [Int8] -> ShowS #
Show Int16	Since: base-2.1
Instance details Defined in GHC.Int Methods showsPrec :: Int -> Int16 -> ShowS # show :: Int16 -> String # showList :: [Int16] -> ShowS #
Show Int32	Since: base-2.1
Instance details Defined in GHC.Int Methods showsPrec :: Int -> Int32 -> ShowS # show :: Int32 -> String # showList :: [Int32] -> ShowS #
Show Int64	Since: base-2.1
Instance details Defined in GHC.Int Methods showsPrec :: Int -> Int64 -> ShowS # show :: Int64 -> String # showList :: [Int64] -> ShowS #
Show Integer	Since: base-2.1
Instance details Defined in GHC.Show Methods showsPrec :: Int -> Integer -> ShowS # show :: Integer -> String # showList :: [Integer] -> ShowS #
Show Natural	Since: base-4.8.0.0
Instance details Defined in GHC.Show Methods showsPrec :: Int -> Natural -> ShowS # show :: Natural -> String # showList :: [Natural] -> ShowS #
Show Ordering	Since: base-2.1
Instance details Defined in GHC.Show Methods showsPrec :: Int -> Ordering -> ShowS # show :: Ordering -> String # showList :: [Ordering] -> ShowS #
Show Word	Since: base-2.1
Instance details Defined in GHC.Show Methods showsPrec :: Int -> Word -> ShowS # show :: Word -> String # showList :: [Word] -> ShowS #
Show Word8	Since: base-2.1
Instance details Defined in GHC.Word Methods showsPrec :: Int -> Word8 -> ShowS # show :: Word8 -> String # showList :: [Word8] -> ShowS #
Show Word16	Since: base-2.1
Instance details Defined in GHC.Word Methods showsPrec :: Int -> Word16 -> ShowS # show :: Word16 -> String # showList :: [Word16] -> ShowS #
Show Word32	Since: base-2.1
Instance details Defined in GHC.Word Methods showsPrec :: Int -> Word32 -> ShowS # show :: Word32 -> String # showList :: [Word32] -> ShowS #
Show Word64	Since: base-2.1
Instance details Defined in GHC.Word Methods showsPrec :: Int -> Word64 -> ShowS # show :: Word64 -> String # showList :: [Word64] -> ShowS #
Show RuntimeRep	Since: base-4.11.0.0
Instance details Defined in GHC.Show Methods showsPrec :: Int -> RuntimeRep -> ShowS # show :: RuntimeRep -> String # showList :: [RuntimeRep] -> ShowS #
Show VecCount	Since: base-4.11.0.0
Instance details Defined in GHC.Show Methods showsPrec :: Int -> VecCount -> ShowS # show :: VecCount -> String # showList :: [VecCount] -> ShowS #
Show VecElem	Since: base-4.11.0.0
Instance details Defined in GHC.Show Methods showsPrec :: Int -> VecElem -> ShowS # show :: VecElem -> String # showList :: [VecElem] -> ShowS #
Show CallStack	Since: base-4.9.0.0
Instance details Defined in GHC.Show Methods showsPrec :: Int -> CallStack -> ShowS # show :: CallStack -> String # showList :: [CallStack] -> ShowS #
Show SomeTypeRep	Since: base-4.10.0.0
Instance details Defined in Data.Typeable.Internal Methods showsPrec :: Int -> SomeTypeRep -> ShowS # show :: SomeTypeRep -> String # showList :: [SomeTypeRep] -> ShowS #
Show ()	Since: base-2.1
Instance details Defined in GHC.Show Methods showsPrec :: Int -> () -> ShowS # show :: () -> String # showList :: [()] -> ShowS #
Show TyCon	Since: base-2.1
Instance details Defined in GHC.Show Methods showsPrec :: Int -> TyCon -> ShowS # show :: TyCon -> String # showList :: [TyCon] -> ShowS #
Show Module	Since: base-4.9.0.0
Instance details Defined in GHC.Show Methods showsPrec :: Int -> Module -> ShowS # show :: Module -> String # showList :: [Module] -> ShowS #
Show TrName	Since: base-4.9.0.0
Instance details Defined in GHC.Show Methods showsPrec :: Int -> TrName -> ShowS # show :: TrName -> String # showList :: [TrName] -> ShowS #
Show KindRep
Instance details Defined in GHC.Show Methods showsPrec :: Int -> KindRep -> ShowS # show :: KindRep -> String # showList :: [KindRep] -> ShowS #
Show TypeLitSort	Since: base-4.11.0.0
Instance details Defined in GHC.Show Methods showsPrec :: Int -> TypeLitSort -> ShowS # show :: TypeLitSort -> String # showList :: [TypeLitSort] -> ShowS #
Show Handle	Since: base-4.1.0.0
Instance details Defined in GHC.IO.Handle.Types Methods showsPrec :: Int -> Handle -> ShowS # show :: Handle -> String # showList :: [Handle] -> ShowS #
Show HandleType	Since: base-4.1.0.0
Instance details Defined in GHC.IO.Handle.Types Methods showsPrec :: Int -> HandleType -> ShowS # show :: HandleType -> String # showList :: [HandleType] -> ShowS #
Show Void	Since: base-4.8.0.0
Instance details Defined in Data.Void Methods showsPrec :: Int -> Void -> ShowS # show :: Void -> String # showList :: [Void] -> ShowS #
Show Version	Since: base-2.1
Instance details Defined in Data.Version Methods showsPrec :: Int -> Version -> ShowS # show :: Version -> String # showList :: [Version] -> ShowS #
Show ThreadId	Since: base-4.2.0.0
Instance details Defined in GHC.Conc.Sync Methods showsPrec :: Int -> ThreadId -> ShowS # show :: ThreadId -> String # showList :: [ThreadId] -> ShowS #
Show BlockReason	Since: base-4.3.0.0
Instance details Defined in GHC.Conc.Sync Methods showsPrec :: Int -> BlockReason -> ShowS # show :: BlockReason -> String # showList :: [BlockReason] -> ShowS #
Show ThreadStatus	Since: base-4.3.0.0
Instance details Defined in GHC.Conc.Sync Methods showsPrec :: Int -> ThreadStatus -> ShowS # show :: ThreadStatus -> String # showList :: [ThreadStatus] -> ShowS #
Show BlockedIndefinitelyOnMVar	Since: base-4.1.0.0
Instance details Defined in GHC.IO.Exception Methods showsPrec :: Int -> BlockedIndefinitelyOnMVar -> ShowS # show :: BlockedIndefinitelyOnMVar -> String # showList :: [BlockedIndefinitelyOnMVar] -> ShowS #
Show BlockedIndefinitelyOnSTM	Since: base-4.1.0.0
Instance details Defined in GHC.IO.Exception Methods showsPrec :: Int -> BlockedIndefinitelyOnSTM -> ShowS # show :: BlockedIndefinitelyOnSTM -> String # showList :: [BlockedIndefinitelyOnSTM] -> ShowS #
Show Deadlock	Since: base-4.1.0.0
Instance details Defined in GHC.IO.Exception Methods showsPrec :: Int -> Deadlock -> ShowS # show :: Deadlock -> String # showList :: [Deadlock] -> ShowS #
Show AllocationLimitExceeded	Since: base-4.7.1.0
Instance details Defined in GHC.IO.Exception Methods showsPrec :: Int -> AllocationLimitExceeded -> ShowS # show :: AllocationLimitExceeded -> String # showList :: [AllocationLimitExceeded] -> ShowS #
Show CompactionFailed	Since: base-4.10.0.0
Instance details Defined in GHC.IO.Exception Methods showsPrec :: Int -> CompactionFailed -> ShowS # show :: CompactionFailed -> String # showList :: [CompactionFailed] -> ShowS #
Show AssertionFailed	Since: base-4.1.0.0
Instance details Defined in GHC.IO.Exception Methods showsPrec :: Int -> AssertionFailed -> ShowS # show :: AssertionFailed -> String # showList :: [AssertionFailed] -> ShowS #
Show SomeAsyncException	Since: base-4.7.0.0
Instance details Defined in GHC.IO.Exception Methods showsPrec :: Int -> SomeAsyncException -> ShowS # show :: SomeAsyncException -> String # showList :: [SomeAsyncException] -> ShowS #
Show AsyncException	Since: base-4.1.0.0
Instance details Defined in GHC.IO.Exception Methods showsPrec :: Int -> AsyncException -> ShowS # show :: AsyncException -> String # showList :: [AsyncException] -> ShowS #
Show ArrayException	Since: base-4.1.0.0
Instance details Defined in GHC.IO.Exception Methods showsPrec :: Int -> ArrayException -> ShowS # show :: ArrayException -> String # showList :: [ArrayException] -> ShowS #
Show FixIOException	Since: base-4.11.0.0
Instance details Defined in GHC.IO.Exception Methods showsPrec :: Int -> FixIOException -> ShowS # show :: FixIOException -> String # showList :: [FixIOException] -> ShowS #
Show ExitCode
Instance details Defined in GHC.IO.Exception Methods showsPrec :: Int -> ExitCode -> ShowS # show :: ExitCode -> String # showList :: [ExitCode] -> ShowS #
Show IOErrorType	Since: base-4.1.0.0
Instance details Defined in GHC.IO.Exception Methods showsPrec :: Int -> IOErrorType -> ShowS # show :: IOErrorType -> String # showList :: [IOErrorType] -> ShowS #
Show BufferMode	Since: base-4.2.0.0
Instance details Defined in GHC.IO.Handle.Types Methods showsPrec :: Int -> BufferMode -> ShowS # show :: BufferMode -> String # showList :: [BufferMode] -> ShowS #
Show Newline	Since: base-4.3.0.0
Instance details Defined in GHC.IO.Handle.Types Methods showsPrec :: Int -> Newline -> ShowS # show :: Newline -> String # showList :: [Newline] -> ShowS #
Show NewlineMode	Since: base-4.3.0.0
Instance details Defined in GHC.IO.Handle.Types Methods showsPrec :: Int -> NewlineMode -> ShowS # show :: NewlineMode -> String # showList :: [NewlineMode] -> ShowS #
Show MaskingState	Since: base-4.3.0.0
Instance details Defined in GHC.IO Methods showsPrec :: Int -> MaskingState -> ShowS # show :: MaskingState -> String # showList :: [MaskingState] -> ShowS #
Show IOException	Since: base-4.1.0.0
Instance details Defined in GHC.IO.Exception Methods showsPrec :: Int -> IOException -> ShowS # show :: IOException -> String # showList :: [IOException] -> ShowS #
Show ErrorCall	Since: base-4.0.0.0
Instance details Defined in GHC.Exception Methods showsPrec :: Int -> ErrorCall -> ShowS # show :: ErrorCall -> String # showList :: [ErrorCall] -> ShowS #
Show ArithException	Since: base-4.0.0.0
Instance details Defined in GHC.Exception.Type Methods showsPrec :: Int -> ArithException -> ShowS # show :: ArithException -> String # showList :: [ArithException] -> ShowS #
Show All	Since: base-2.1
Instance details Defined in Data.Semigroup.Internal Methods showsPrec :: Int -> All -> ShowS # show :: All -> String # showList :: [All] -> ShowS #
Show Any	Since: base-2.1
Instance details Defined in Data.Semigroup.Internal Methods showsPrec :: Int -> Any -> ShowS # show :: Any -> String # showList :: [Any] -> ShowS #
Show Fixity	Since: base-4.6.0.0
Instance details Defined in GHC.Generics Methods showsPrec :: Int -> Fixity -> ShowS # show :: Fixity -> String # showList :: [Fixity] -> ShowS #
Show Associativity	Since: base-4.6.0.0
Instance details Defined in GHC.Generics Methods showsPrec :: Int -> Associativity -> ShowS # show :: Associativity -> String # showList :: [Associativity] -> ShowS #
Show SourceUnpackedness	Since: base-4.9.0.0
Instance details Defined in GHC.Generics Methods showsPrec :: Int -> SourceUnpackedness -> ShowS # show :: SourceUnpackedness -> String # showList :: [SourceUnpackedness] -> ShowS #
Show SourceStrictness	Since: base-4.9.0.0
Instance details Defined in GHC.Generics Methods showsPrec :: Int -> SourceStrictness -> ShowS # show :: SourceStrictness -> String # showList :: [SourceStrictness] -> ShowS #
Show DecidedStrictness	Since: base-4.9.0.0
Instance details Defined in GHC.Generics Methods showsPrec :: Int -> DecidedStrictness -> ShowS # show :: DecidedStrictness -> String # showList :: [DecidedStrictness] -> ShowS #
Show SomeNat	Since: base-4.7.0.0
Instance details Defined in GHC.TypeNats Methods showsPrec :: Int -> SomeNat -> ShowS # show :: SomeNat -> String # showList :: [SomeNat] -> ShowS #
Show IOMode	Since: base-4.2.0.0
Instance details Defined in GHC.IO.IOMode Methods showsPrec :: Int -> IOMode -> ShowS # show :: IOMode -> String # showList :: [IOMode] -> ShowS #
Show SrcLoc	Since: base-4.9.0.0
Instance details Defined in GHC.Show Methods showsPrec :: Int -> SrcLoc -> ShowS # show :: SrcLoc -> String # showList :: [SrcLoc] -> ShowS #
Show SomeException	Since: base-3.0
Instance details Defined in GHC.Exception.Type Methods showsPrec :: Int -> SomeException -> ShowS # show :: SomeException -> String # showList :: [SomeException] -> ShowS #
Show ByteString
Instance details Defined in Data.ByteString.Internal Methods showsPrec :: Int -> ByteString -> ShowS # show :: ByteString -> String # showList :: [ByteString] -> ShowS #
Show IntSet
Instance details Defined in Data.IntSet.Internal Methods showsPrec :: Int -> IntSet -> ShowS # show :: IntSet -> String # showList :: [IntSet] -> ShowS #
Show StringException
Instance details Defined in Control.Exception.Safe Methods showsPrec :: Int -> StringException -> ShowS # show :: StringException -> String # showList :: [StringException] -> ShowS #
Show SyncExceptionWrapper
Instance details Defined in Control.Exception.Safe Methods showsPrec :: Int -> SyncExceptionWrapper -> ShowS # show :: SyncExceptionWrapper -> String # showList :: [SyncExceptionWrapper] -> ShowS #
Show AsyncExceptionWrapper
Instance details Defined in Control.Exception.Safe Methods showsPrec :: Int -> AsyncExceptionWrapper -> ShowS # show :: AsyncExceptionWrapper -> String # showList :: [AsyncExceptionWrapper] -> ShowS #
Show Decoding
Instance details Defined in Data.Text.Encoding Methods showsPrec :: Int -> Decoding -> ShowS # show :: Decoding -> String # showList :: [Decoding] -> ShowS #
Show UnicodeException
Instance details Defined in Data.Text.Encoding.Error Methods showsPrec :: Int -> UnicodeException -> ShowS # show :: UnicodeException -> String # showList :: [UnicodeException] -> ShowS #
Show Undefined
Instance details Defined in Universum.Debug Methods showsPrec :: Int -> Undefined -> ShowS # show :: Undefined -> String # showList :: [Undefined] -> ShowS #
Show Bug
Instance details Defined in Universum.Exception Methods showsPrec :: Int -> Bug -> ShowS # show :: Bug -> String # showList :: [Bug] -> ShowS #
Show CodePoint
Instance details Defined in Data.Text.Encoding Methods showsPrec :: Int -> CodePoint -> ShowS # show :: CodePoint -> String # showList :: [CodePoint] -> ShowS #
Show DecoderState
Instance details Defined in Data.Text.Encoding Methods showsPrec :: Int -> DecoderState -> ShowS # show :: DecoderState -> String # showList :: [DecoderState] -> ShowS #
Show a => Show [a]	Since: base-2.1
Instance details Defined in GHC.Show Methods showsPrec :: Int -> [a] -> ShowS # show :: [a] -> String # showList :: [[a]] -> ShowS #
Show a => Show (Maybe a)	Since: base-2.1
Instance details Defined in GHC.Show Methods showsPrec :: Int -> Maybe a -> ShowS # show :: Maybe a -> String # showList :: [Maybe a] -> ShowS #
Show a => Show (Ratio a)	Since: base-2.0.1
Instance details Defined in GHC.Real Methods showsPrec :: Int -> Ratio a -> ShowS # show :: Ratio a -> String # showList :: [Ratio a] -> ShowS #
Show (Ptr a)	Since: base-2.1
Instance details Defined in GHC.Ptr Methods showsPrec :: Int -> Ptr a -> ShowS # show :: Ptr a -> String # showList :: [Ptr a] -> ShowS #
Show (FunPtr a)	Since: base-2.1
Instance details Defined in GHC.Ptr Methods showsPrec :: Int -> FunPtr a -> ShowS # show :: FunPtr a -> String # showList :: [FunPtr a] -> ShowS #
Show p => Show (Par1 p)	Since: base-4.7.0.0
Instance details Defined in GHC.Generics Methods showsPrec :: Int -> Par1 p -> ShowS # show :: Par1 p -> String # showList :: [Par1 p] -> ShowS #
Show a => Show (Min a)	Since: base-4.9.0.0
Instance details Defined in Data.Semigroup Methods showsPrec :: Int -> Min a -> ShowS # show :: Min a -> String # showList :: [Min a] -> ShowS #
Show a => Show (Max a)	Since: base-4.9.0.0
Instance details Defined in Data.Semigroup Methods showsPrec :: Int -> Max a -> ShowS # show :: Max a -> String # showList :: [Max a] -> ShowS #
Show a => Show (First a)	Since: base-4.9.0.0
Instance details Defined in Data.Semigroup Methods showsPrec :: Int -> First a -> ShowS # show :: First a -> String # showList :: [First a] -> ShowS #
Show a => Show (Last a)	Since: base-4.9.0.0
Instance details Defined in Data.Semigroup Methods showsPrec :: Int -> Last a -> ShowS # show :: Last a -> String # showList :: [Last a] -> ShowS #
Show m => Show (WrappedMonoid m)	Since: base-4.9.0.0
Instance details Defined in Data.Semigroup Methods showsPrec :: Int -> WrappedMonoid m -> ShowS # show :: WrappedMonoid m -> String # showList :: [WrappedMonoid m] -> ShowS #
Show a => Show (Option a)	Since: base-4.9.0.0
Instance details Defined in Data.Semigroup Methods showsPrec :: Int -> Option a -> ShowS # show :: Option a -> String # showList :: [Option a] -> ShowS #
Show a => Show (ZipList a)	Since: base-4.7.0.0
Instance details Defined in Control.Applicative Methods showsPrec :: Int -> ZipList a -> ShowS # show :: ZipList a -> String # showList :: [ZipList a] -> ShowS #
Show a => Show (Identity a)	This instance would be equivalent to the derived instances of the `Identity` newtype if the `runIdentity` field were removed Since: base-4.8.0.0
Instance details Defined in Data.Functor.Identity Methods showsPrec :: Int -> Identity a -> ShowS # show :: Identity a -> String # showList :: [Identity a] -> ShowS #
Show a => Show (First a)	Since: base-2.1
Instance details Defined in Data.Monoid Methods showsPrec :: Int -> First a -> ShowS # show :: First a -> String # showList :: [First a] -> ShowS #
Show a => Show (Last a)	Since: base-2.1
Instance details Defined in Data.Monoid Methods showsPrec :: Int -> Last a -> ShowS # show :: Last a -> String # showList :: [Last a] -> ShowS #
Show a => Show (Dual a)	Since: base-2.1
Instance details Defined in Data.Semigroup.Internal Methods showsPrec :: Int -> Dual a -> ShowS # show :: Dual a -> String # showList :: [Dual a] -> ShowS #
Show a => Show (Sum a)	Since: base-2.1
Instance details Defined in Data.Semigroup.Internal Methods showsPrec :: Int -> Sum a -> ShowS # show :: Sum a -> String # showList :: [Sum a] -> ShowS #
Show a => Show (Product a)	Since: base-2.1
Instance details Defined in Data.Semigroup.Internal Methods showsPrec :: Int -> Product a -> ShowS # show :: Product a -> String # showList :: [Product a] -> ShowS #
Show a => Show (Down a)	Since: base-4.7.0.0
Instance details Defined in Data.Ord Methods showsPrec :: Int -> Down a -> ShowS # show :: Down a -> String # showList :: [Down a] -> ShowS #
Show a => Show (NonEmpty a)	Since: base-4.11.0.0
Instance details Defined in GHC.Show Methods showsPrec :: Int -> NonEmpty a -> ShowS # show :: NonEmpty a -> String # showList :: [NonEmpty a] -> ShowS #
Show a => Show (IntMap a)
Instance details Defined in Data.IntMap.Internal Methods showsPrec :: Int -> IntMap a -> ShowS # show :: IntMap a -> String # showList :: [IntMap a] -> ShowS #
Show a => Show (Seq a)
Instance details Defined in Data.Sequence.Internal Methods showsPrec :: Int -> Seq a -> ShowS # show :: Seq a -> String # showList :: [Seq a] -> ShowS #
Show a => Show (ViewL a)
Instance details Defined in Data.Sequence.Internal Methods showsPrec :: Int -> ViewL a -> ShowS # show :: ViewL a -> String # showList :: [ViewL a] -> ShowS #
Show a => Show (ViewR a)
Instance details Defined in Data.Sequence.Internal Methods showsPrec :: Int -> ViewR a -> ShowS # show :: ViewR a -> String # showList :: [ViewR a] -> ShowS #
Show a => Show (Set a)
Instance details Defined in Data.Set.Internal Methods showsPrec :: Int -> Set a -> ShowS # show :: Set a -> String # showList :: [Set a] -> ShowS #
Show a => Show (ExitCase a)
Instance details Defined in Control.Monad.Catch Methods showsPrec :: Int -> ExitCase a -> ShowS # show :: ExitCase a -> String # showList :: [ExitCase a] -> ShowS #
Show a => Show (Hashed a)
Instance details Defined in Data.Hashable.Class Methods showsPrec :: Int -> Hashed a -> ShowS # show :: Hashed a -> String # showList :: [Hashed a] -> ShowS #
Show a => Show (Vector a)
Instance details Defined in Data.Vector Methods showsPrec :: Int -> Vector a -> ShowS # show :: Vector a -> String # showList :: [Vector a] -> ShowS #
Show a => Show (HashSet a)
Instance details Defined in Data.HashSet.Base Methods showsPrec :: Int -> HashSet a -> ShowS # show :: HashSet a -> String # showList :: [HashSet a] -> ShowS #
(Show a, Show b) => Show (Either a b)	Since: base-3.0
Instance details Defined in Data.Either Methods showsPrec :: Int -> Either a b -> ShowS # show :: Either a b -> String # showList :: [Either a b] -> ShowS #
Show (V1 p)	Since: base-4.9.0.0
Instance details Defined in GHC.Generics Methods showsPrec :: Int -> V1 p -> ShowS # show :: V1 p -> String # showList :: [V1 p] -> ShowS #
Show (U1 p)	Since: base-4.9.0.0
Instance details Defined in GHC.Generics Methods showsPrec :: Int -> U1 p -> ShowS # show :: U1 p -> String # showList :: [U1 p] -> ShowS #
Show (TypeRep a)
Instance details Defined in Data.Typeable.Internal Methods showsPrec :: Int -> TypeRep a -> ShowS # show :: TypeRep a -> String # showList :: [TypeRep a] -> ShowS #
(Show a, Show b) => Show (a, b)	Since: base-2.1
Instance details Defined in GHC.Show Methods showsPrec :: Int -> (a, b) -> ShowS # show :: (a, b) -> String # showList :: [(a, b)] -> ShowS #
(Show a, Show b) => Show (Arg a b)	Since: base-4.9.0.0
Instance details Defined in Data.Semigroup Methods showsPrec :: Int -> Arg a b -> ShowS # show :: Arg a b -> String # showList :: [Arg a b] -> ShowS #
Show (Proxy s)	Since: base-4.7.0.0
Instance details Defined in Data.Proxy Methods showsPrec :: Int -> Proxy s -> ShowS # show :: Proxy s -> String # showList :: [Proxy s] -> ShowS #
(Show k, Show a) => Show (Map k a)
Instance details Defined in Data.Map.Internal Methods showsPrec :: Int -> Map k a -> ShowS # show :: Map k a -> String # showList :: [Map k a] -> ShowS #
(Show1 m, Show a) => Show (MaybeT m a)
Instance details Defined in Control.Monad.Trans.Maybe Methods showsPrec :: Int -> MaybeT m a -> ShowS # show :: MaybeT m a -> String # showList :: [MaybeT m a] -> ShowS #
(Show k, Show v) => Show (HashMap k v)
Instance details Defined in Data.HashMap.Base Methods showsPrec :: Int -> HashMap k v -> ShowS # show :: HashMap k v -> String # showList :: [HashMap k v] -> ShowS #
Show (f p) => Show (Rec1 f p)	Since: base-4.7.0.0
Instance details Defined in GHC.Generics Methods showsPrec :: Int -> Rec1 f p -> ShowS # show :: Rec1 f p -> String # showList :: [Rec1 f p] -> ShowS #
Show (URec Char p)	Since: base-4.9.0.0
Instance details Defined in GHC.Generics Methods showsPrec :: Int -> URec Char p -> ShowS # show :: URec Char p -> String # showList :: [URec Char p] -> ShowS #
Show (URec Double p)	Since: base-4.9.0.0
Instance details Defined in GHC.Generics Methods showsPrec :: Int -> URec Double p -> ShowS # show :: URec Double p -> String # showList :: [URec Double p] -> ShowS #
Show (URec Float p)
Instance details Defined in GHC.Generics Methods showsPrec :: Int -> URec Float p -> ShowS # show :: URec Float p -> String # showList :: [URec Float p] -> ShowS #
Show (URec Int p)	Since: base-4.9.0.0
Instance details Defined in GHC.Generics Methods showsPrec :: Int -> URec Int p -> ShowS # show :: URec Int p -> String # showList :: [URec Int p] -> ShowS #
Show (URec Word p)	Since: base-4.9.0.0
Instance details Defined in GHC.Generics Methods showsPrec :: Int -> URec Word p -> ShowS # show :: URec Word p -> String # showList :: [URec Word p] -> ShowS #
(Show a, Show b, Show c) => Show (a, b, c)	Since: base-2.1
Instance details Defined in GHC.Show Methods showsPrec :: Int -> (a, b, c) -> ShowS # show :: (a, b, c) -> String # showList :: [(a, b, c)] -> ShowS #
Show a => Show (Const a b)	This instance would be equivalent to the derived instances of the `Const` newtype if the `runConst` field were removed Since: base-4.8.0.0
Instance details Defined in Data.Functor.Const Methods showsPrec :: Int -> Const a b -> ShowS # show :: Const a b -> String # showList :: [Const a b] -> ShowS #
Show (f a) => Show (Ap f a)	Since: base-4.12.0.0
Instance details Defined in Data.Monoid Methods showsPrec :: Int -> Ap f a -> ShowS # show :: Ap f a -> String # showList :: [Ap f a] -> ShowS #
Show (f a) => Show (Alt f a)	Since: base-4.8.0.0
Instance details Defined in Data.Semigroup.Internal Methods showsPrec :: Int -> Alt f a -> ShowS # show :: Alt f a -> String # showList :: [Alt f a] -> ShowS #
Show (a :~: b)	Since: base-4.7.0.0
Instance details Defined in Data.Type.Equality Methods showsPrec :: Int -> (a :~: b) -> ShowS # show :: (a :~: b) -> String # showList :: [a :~: b] -> ShowS #
(Show e, Show1 m, Show a) => Show (ExceptT e m a)
Instance details Defined in Control.Monad.Trans.Except Methods showsPrec :: Int -> ExceptT e m a -> ShowS # show :: ExceptT e m a -> String # showList :: [ExceptT e m a] -> ShowS #
(Show1 f, Show a) => Show (IdentityT f a)
Instance details Defined in Control.Monad.Trans.Identity Methods showsPrec :: Int -> IdentityT f a -> ShowS # show :: IdentityT f a -> String # showList :: [IdentityT f a] -> ShowS #
(Show e, Show1 m, Show a) => Show (ErrorT e m a)
Instance details Defined in Control.Monad.Trans.Error Methods showsPrec :: Int -> ErrorT e m a -> ShowS # show :: ErrorT e m a -> String # showList :: [ErrorT e m a] -> ShowS #
Show c => Show (K1 i c p)	Since: base-4.7.0.0
Instance details Defined in GHC.Generics Methods showsPrec :: Int -> K1 i c p -> ShowS # show :: K1 i c p -> String # showList :: [K1 i c p] -> ShowS #
(Show (f p), Show (g p)) => Show ((f :+: g) p)	Since: base-4.7.0.0
Instance details Defined in GHC.Generics Methods showsPrec :: Int -> (f :+: g) p -> ShowS # show :: (f :+: g) p -> String # showList :: [(f :+: g) p] -> ShowS #
(Show (f p), Show (g p)) => Show ((f :*: g) p)	Since: base-4.7.0.0
Instance details Defined in GHC.Generics Methods showsPrec :: Int -> (f :: g) p -> ShowS # show :: (f :: g) p -> String # showList :: [(f :*: g) p] -> ShowS #
(Show a, Show b, Show c, Show d) => Show (a, b, c, d)	Since: base-2.1
Instance details Defined in GHC.Show Methods showsPrec :: Int -> (a, b, c, d) -> ShowS # show :: (a, b, c, d) -> String # showList :: [(a, b, c, d)] -> ShowS #
Show (a :~~: b)	Since: base-4.10.0.0
Instance details Defined in Data.Type.Equality Methods showsPrec :: Int -> (a :~~: b) -> ShowS # show :: (a :~~: b) -> String # showList :: [a :~~: b] -> ShowS #
Show (f p) => Show (M1 i c f p)	Since: base-4.7.0.0
Instance details Defined in GHC.Generics Methods showsPrec :: Int -> M1 i c f p -> ShowS # show :: M1 i c f p -> String # showList :: [M1 i c f p] -> ShowS #
Show (f (g p)) => Show ((f :.: g) p)	Since: base-4.7.0.0
Instance details Defined in GHC.Generics Methods showsPrec :: Int -> (f :.: g) p -> ShowS # show :: (f :.: g) p -> String # showList :: [(f :.: g) p] -> ShowS #
(Show a, Show b, Show c, Show d, Show e) => Show (a, b, c, d, e)	Since: base-2.1
Instance details Defined in GHC.Show Methods showsPrec :: Int -> (a, b, c, d, e) -> ShowS # show :: (a, b, c, d, e) -> String # showList :: [(a, b, c, d, e)] -> ShowS #
(Show1 f, Show1 g, Show a) => Show (Compose f g a)	Since: base-4.9.0.0
Instance details Defined in Data.Functor.Compose Methods showsPrec :: Int -> Compose f g a -> ShowS # show :: Compose f g a -> String # showList :: [Compose f g a] -> ShowS #
(Show a, Show b, Show c, Show d, Show e, Show f) => Show (a, b, c, d, e, f)	Since: base-2.1
Instance details Defined in GHC.Show Methods showsPrec :: Int -> (a, b, c, d, e, f) -> ShowS # show :: (a, b, c, d, e, f) -> String # showList :: [(a, b, c, d, e, f)] -> ShowS #
(Show a, Show b, Show c, Show d, Show e, Show f, Show g) => Show (a, b, c, d, e, f, g)	Since: base-2.1
Instance details Defined in GHC.Show Methods showsPrec :: Int -> (a, b, c, d, e, f, g) -> ShowS # show :: (a, b, c, d, e, f, g) -> String # showList :: [(a, b, c, d, e, f, g)] -> ShowS #
(Show a, Show b, Show c, Show d, Show e, Show f, Show g, Show h) => Show (a, b, c, d, e, f, g, h)	Since: base-2.1
Instance details Defined in GHC.Show Methods showsPrec :: Int -> (a, b, c, d, e, f, g, h) -> ShowS # show :: (a, b, c, d, e, f, g, h) -> String # showList :: [(a, b, c, d, e, f, g, h)] -> ShowS #
(Show a, Show b, Show c, Show d, Show e, Show f, Show g, Show h, Show i) => Show (a, b, c, d, e, f, g, h, i)	Since: base-2.1
Instance details Defined in GHC.Show Methods showsPrec :: Int -> (a, b, c, d, e, f, g, h, i) -> ShowS # show :: (a, b, c, d, e, f, g, h, i) -> String # showList :: [(a, b, c, d, e, f, g, h, i)] -> ShowS #
(Show a, Show b, Show c, Show d, Show e, Show f, Show g, Show h, Show i, Show j) => Show (a, b, c, d, e, f, g, h, i, j)	Since: base-2.1
Instance details Defined in GHC.Show Methods showsPrec :: Int -> (a, b, c, d, e, f, g, h, i, j) -> ShowS # show :: (a, b, c, d, e, f, g, h, i, j) -> String # showList :: [(a, b, c, d, e, f, g, h, i, j)] -> ShowS #
(Show a, Show b, Show c, Show d, Show e, Show f, Show g, Show h, Show i, Show j, Show k) => Show (a, b, c, d, e, f, g, h, i, j, k)	Since: base-2.1
Instance details Defined in GHC.Show Methods showsPrec :: Int -> (a, b, c, d, e, f, g, h, i, j, k) -> ShowS # show :: (a, b, c, d, e, f, g, h, i, j, k) -> String # showList :: [(a, b, c, d, e, f, g, h, i, j, k)] -> ShowS #
(Show a, Show b, Show c, Show d, Show e, Show f, Show g, Show h, Show i, Show j, Show k, Show l) => Show (a, b, c, d, e, f, g, h, i, j, k, l)	Since: base-2.1
Instance details Defined in GHC.Show Methods showsPrec :: Int -> (a, b, c, d, e, f, g, h, i, j, k, l) -> ShowS # show :: (a, b, c, d, e, f, g, h, i, j, k, l) -> String # showList :: [(a, b, c, d, e, f, g, h, i, j, k, l)] -> ShowS #
(Show a, Show b, Show c, Show d, Show e, Show f, Show g, Show h, Show i, Show j, Show k, Show l, Show m) => Show (a, b, c, d, e, f, g, h, i, j, k, l, m)	Since: base-2.1
Instance details Defined in GHC.Show Methods showsPrec :: Int -> (a, b, c, d, e, f, g, h, i, j, k, l, m) -> ShowS # show :: (a, b, c, d, e, f, g, h, i, j, k, l, m) -> String # showList :: [(a, b, c, d, e, f, g, h, i, j, k, l, m)] -> ShowS #
(Show a, Show b, Show c, Show d, Show e, Show f, Show g, Show h, Show i, Show j, Show k, Show l, Show m, Show n) => Show (a, b, c, d, e, f, g, h, i, j, k, l, m, n)	Since: base-2.1
Instance details Defined in GHC.Show Methods showsPrec :: Int -> (a, b, c, d, e, f, g, h, i, j, k, l, m, n) -> ShowS # show :: (a, b, c, d, e, f, g, h, i, j, k, l, m, n) -> String # showList :: [(a, b, c, d, e, f, g, h, i, j, k, l, m, n)] -> ShowS #
(Show a, Show b, Show c, Show d, Show e, Show f, Show g, Show h, Show i, Show j, Show k, Show l, Show m, Show n, Show o) => Show (a, b, c, d, e, f, g, h, i, j, k, l, m, n, o)	Since: base-2.1
Instance details Defined in GHC.Show Methods showsPrec :: Int -> (a, b, c, d, e, f, g, h, i, j, k, l, m, n, o) -> ShowS # show :: (a, b, c, d, e, f, g, h, i, j, k, l, m, n, o) -> String # showList :: [(a, b, c, d, e, f, g, h, i, j, k, l, m, n, o)] -> ShowS #

class Typeable (a :: k) #

The class Typeable allows a concrete representation of a type to be calculated.

Minimal complete definition

typeRep#

class Monad m => MonadFail (m :: Type -> Type) where #

When a value is bound in do-notation, the pattern on the left hand side of <- might not match. In this case, this class provides a function to recover.

A Monad without a MonadFail instance may only be used in conjunction with pattern that always match, such as newtypes, tuples, data types with only a single data constructor, and irrefutable patterns (~pat).

Instances of MonadFail should satisfy the following law: fail s should be a left zero for >>=,

fail s >>= f  =  fail s

If your Monad is also MonadPlus, a popular definition is

fail _ = mzero

Since: base-4.9.0.0

Methods

fail :: String -> m a #

Instances

MonadFail []	Since: base-4.9.0.0
Instance details Defined in Control.Monad.Fail Methods fail :: String -> [a] #
MonadFail Maybe	Since: base-4.9.0.0
Instance details Defined in Control.Monad.Fail Methods fail :: String -> Maybe a #
MonadFail IO	Since: base-4.9.0.0
Instance details Defined in Control.Monad.Fail Methods fail :: String -> IO a #
MonadFail ReadP	Since: base-4.9.0.0
Instance details Defined in Text.ParserCombinators.ReadP Methods fail :: String -> ReadP a #
MonadFail Vector
Instance details Defined in Data.Vector Methods fail :: String -> Vector a #
MonadFail P	Since: base-4.9.0.0
Instance details Defined in Text.ParserCombinators.ReadP Methods fail :: String -> P a #
Monad m => MonadFail (MaybeT m)
Instance details Defined in Control.Monad.Trans.Maybe Methods fail :: String -> MaybeT m a #
MonadFail f => MonadFail (Ap f)	Since: base-4.12.0.0
Instance details Defined in Data.Monoid Methods fail :: String -> Ap f a #
MonadFail m => MonadFail (ExceptT e m)
Instance details Defined in Control.Monad.Trans.Except Methods fail :: String -> ExceptT e m a #
MonadFail m => MonadFail (IdentityT m)
Instance details Defined in Control.Monad.Trans.Identity Methods fail :: String -> IdentityT m a #
(Monad m, Error e) => MonadFail (ErrorT e m)
Instance details Defined in Control.Monad.Trans.Error Methods fail :: String -> ErrorT e m a #
MonadFail m => MonadFail (StateT s m)
Instance details Defined in Control.Monad.Trans.State.Strict Methods fail :: String -> StateT s m a #
MonadFail m => MonadFail (StateT s m)
Instance details Defined in Lens.Micro Methods fail :: String -> StateT s m a #
MonadFail m => MonadFail (ReaderT r m)
Instance details Defined in Control.Monad.Trans.Reader Methods fail :: String -> ReaderT r m a #

class IsString a where #

Class for string-like datastructures; used by the overloaded string extension (-XOverloadedStrings in GHC).

Methods

fromString :: String -> a #

Instances

IsString ByteString
Instance details Defined in Data.ByteString.Internal Methods fromString :: String -> ByteString #
a ~ Char => IsString [a]	`(a ~ Char)` context was introduced in `4.9.0.0` Since: base-2.1
Instance details Defined in Data.String Methods fromString :: String -> [a] #
IsString a => IsString (Identity a)	Since: base-4.9.0.0
Instance details Defined in Data.String Methods fromString :: String -> Identity a #
a ~ Char => IsString (Seq a)	Since: containers-0.5.7
Instance details Defined in Data.Sequence.Internal Methods fromString :: String -> Seq a #
(IsString a, Hashable a) => IsString (Hashed a)
Instance details Defined in Data.Hashable.Class Methods fromString :: String -> Hashed a #
IsString a => IsString (Const a b)	Since: base-4.9.0.0
Instance details Defined in Data.String Methods fromString :: String -> Const a b #

class Functor f => Applicative (f :: Type -> Type) where #

A functor with application, providing operations to

embed pure expressions (pure), and
sequence computations and combine their results (<*> and liftA2).

A minimal complete definition must include implementations of pure and of either <*> or liftA2. If it defines both, then they must behave the same as their default definitions:

(<*>) = liftA2 id

liftA2 f x y = f <$> x <*> y

Further, any definition must satisfy the following:

identity

pure id <*> v = v

composition

pure (.) <*> u <*> v <*> w = u <*> (v <*> w)

homomorphism

pure f <*> pure x = pure (f x)

interchange

u <*> pure y = pure ($ y) <*> u

The other methods have the following default definitions, which may be overridden with equivalent specialized implementations:

```
u *> v = (id <$ u) <*> v
```
```
u <* v = liftA2 const u v
```

As a consequence of these laws, the Functor instance for f will satisfy

```
fmap f x = pure f <*> x
```

It may be useful to note that supposing

forall x y. p (q x y) = f x . g y

it follows from the above that

liftA2 p (liftA2 q u v) = liftA2 f u . liftA2 g v

If f is also a Monad, it should satisfy

```
pure = return
```
```
(<*>) = ap
```
```
(*>) = (>>)
```

(which implies that pure and <*> satisfy the applicative functor laws).

Minimal complete definition

pure, ((<*>) | liftA2)

Methods

pure :: a -> f a #

Lift a value.

(<*>) :: f (a -> b) -> f a -> f b infixl 4 #

Sequential application.

A few functors support an implementation of <*> that is more efficient than the default one.

liftA2 :: (a -> b -> c) -> f a -> f b -> f c #

Lift a binary function to actions.

Some functors support an implementation of liftA2 that is more efficient than the default one. In particular, if fmap is an expensive operation, it is likely better to use liftA2 than to fmap over the structure and then use <*>.

(*>) :: f a -> f b -> f b infixl 4 #

Sequence actions, discarding the value of the first argument.

(<*) :: f a -> f b -> f a infixl 4 #

Sequence actions, discarding the value of the second argument.

Instances

Applicative []	Since: base-2.1
Instance details Defined in GHC.Base Methods pure :: a -> [a] # (<>) :: [a -> b] -> [a] -> [b] # liftA2 :: (a -> b -> c) -> [a] -> [b] -> [c] # (>) :: [a] -> [b] -> [b] # (<*) :: [a] -> [b] -> [a] #
Applicative Maybe	Since: base-2.1
Instance details Defined in GHC.Base Methods pure :: a -> Maybe a # (<>) :: Maybe (a -> b) -> Maybe a -> Maybe b # liftA2 :: (a -> b -> c) -> Maybe a -> Maybe b -> Maybe c # (>) :: Maybe a -> Maybe b -> Maybe b # (<*) :: Maybe a -> Maybe b -> Maybe a #
Applicative IO	Since: base-2.1
Instance details Defined in GHC.Base Methods pure :: a -> IO a # (<>) :: IO (a -> b) -> IO a -> IO b # liftA2 :: (a -> b -> c) -> IO a -> IO b -> IO c # (>) :: IO a -> IO b -> IO b # (<*) :: IO a -> IO b -> IO a #
Applicative Par1	Since: base-4.9.0.0
Instance details Defined in GHC.Generics Methods pure :: a -> Par1 a # (<>) :: Par1 (a -> b) -> Par1 a -> Par1 b # liftA2 :: (a -> b -> c) -> Par1 a -> Par1 b -> Par1 c # (>) :: Par1 a -> Par1 b -> Par1 b # (<*) :: Par1 a -> Par1 b -> Par1 a #
Applicative Min	Since: base-4.9.0.0
Instance details Defined in Data.Semigroup Methods pure :: a -> Min a # (<>) :: Min (a -> b) -> Min a -> Min b # liftA2 :: (a -> b -> c) -> Min a -> Min b -> Min c # (>) :: Min a -> Min b -> Min b # (<*) :: Min a -> Min b -> Min a #
Applicative Max	Since: base-4.9.0.0
Instance details Defined in Data.Semigroup Methods pure :: a -> Max a # (<>) :: Max (a -> b) -> Max a -> Max b # liftA2 :: (a -> b -> c) -> Max a -> Max b -> Max c # (>) :: Max a -> Max b -> Max b # (<*) :: Max a -> Max b -> Max a #
Applicative First	Since: base-4.9.0.0
Instance details Defined in Data.Semigroup Methods pure :: a -> First a # (<>) :: First (a -> b) -> First a -> First b # liftA2 :: (a -> b -> c) -> First a -> First b -> First c # (>) :: First a -> First b -> First b # (<*) :: First a -> First b -> First a #
Applicative Last	Since: base-4.9.0.0
Instance details Defined in Data.Semigroup Methods pure :: a -> Last a # (<>) :: Last (a -> b) -> Last a -> Last b # liftA2 :: (a -> b -> c) -> Last a -> Last b -> Last c # (>) :: Last a -> Last b -> Last b # (<*) :: Last a -> Last b -> Last a #
Applicative Option	Since: base-4.9.0.0
Instance details Defined in Data.Semigroup Methods pure :: a -> Option a # (<>) :: Option (a -> b) -> Option a -> Option b # liftA2 :: (a -> b -> c) -> Option a -> Option b -> Option c # (>) :: Option a -> Option b -> Option b # (<*) :: Option a -> Option b -> Option a #
Applicative ZipList	f '<$>' 'ZipList' xs1 '<>' ... '<>' 'ZipList' xsN = 'ZipList' (zipWithN f xs1 ... xsN) where `zipWithN` refers to the `zipWith` function of the appropriate arity (`zipWith`, `zipWith3`, `zipWith4`, ...). For example: (\a b c -> stimes c [a, b]) <$> ZipList "abcd" <> ZipList "567" <> ZipList [1..] = ZipList (zipWith3 (\a b c -> stimes c [a, b]) "abcd" "567" [1..]) = ZipList {getZipList = ["a5","b6b6","c7c7c7"]} Since: base-2.1
Instance details Defined in Control.Applicative Methods pure :: a -> ZipList a # (<>) :: ZipList (a -> b) -> ZipList a -> ZipList b # liftA2 :: (a -> b -> c) -> ZipList a -> ZipList b -> ZipList c # (>) :: ZipList a -> ZipList b -> ZipList b # (<*) :: ZipList a -> ZipList b -> ZipList a #
Applicative Identity	Since: base-4.8.0.0
Instance details Defined in Data.Functor.Identity Methods pure :: a -> Identity a # (<>) :: Identity (a -> b) -> Identity a -> Identity b # liftA2 :: (a -> b -> c) -> Identity a -> Identity b -> Identity c # (>) :: Identity a -> Identity b -> Identity b # (<*) :: Identity a -> Identity b -> Identity a #
Applicative STM	Since: base-4.8.0.0
Instance details Defined in GHC.Conc.Sync Methods pure :: a -> STM a # (<>) :: STM (a -> b) -> STM a -> STM b # liftA2 :: (a -> b -> c) -> STM a -> STM b -> STM c # (>) :: STM a -> STM b -> STM b # (<*) :: STM a -> STM b -> STM a #
Applicative First	Since: base-4.8.0.0
Instance details Defined in Data.Monoid Methods pure :: a -> First a # (<>) :: First (a -> b) -> First a -> First b # liftA2 :: (a -> b -> c) -> First a -> First b -> First c # (>) :: First a -> First b -> First b # (<*) :: First a -> First b -> First a #
Applicative Last	Since: base-4.8.0.0
Instance details Defined in Data.Monoid Methods pure :: a -> Last a # (<>) :: Last (a -> b) -> Last a -> Last b # liftA2 :: (a -> b -> c) -> Last a -> Last b -> Last c # (>) :: Last a -> Last b -> Last b # (<*) :: Last a -> Last b -> Last a #
Applicative Dual	Since: base-4.8.0.0
Instance details Defined in Data.Semigroup.Internal Methods pure :: a -> Dual a # (<>) :: Dual (a -> b) -> Dual a -> Dual b # liftA2 :: (a -> b -> c) -> Dual a -> Dual b -> Dual c # (>) :: Dual a -> Dual b -> Dual b # (<*) :: Dual a -> Dual b -> Dual a #
Applicative Sum	Since: base-4.8.0.0
Instance details Defined in Data.Semigroup.Internal Methods pure :: a -> Sum a # (<>) :: Sum (a -> b) -> Sum a -> Sum b # liftA2 :: (a -> b -> c) -> Sum a -> Sum b -> Sum c # (>) :: Sum a -> Sum b -> Sum b # (<*) :: Sum a -> Sum b -> Sum a #
Applicative Product	Since: base-4.8.0.0
Instance details Defined in Data.Semigroup.Internal Methods pure :: a -> Product a # (<>) :: Product (a -> b) -> Product a -> Product b # liftA2 :: (a -> b -> c) -> Product a -> Product b -> Product c # (>) :: Product a -> Product b -> Product b # (<*) :: Product a -> Product b -> Product a #
Applicative Down	Since: base-4.11.0.0
Instance details Defined in Data.Ord Methods pure :: a -> Down a # (<>) :: Down (a -> b) -> Down a -> Down b # liftA2 :: (a -> b -> c) -> Down a -> Down b -> Down c # (>) :: Down a -> Down b -> Down b # (<*) :: Down a -> Down b -> Down a #
Applicative ReadP	Since: base-4.6.0.0
Instance details Defined in Text.ParserCombinators.ReadP Methods pure :: a -> ReadP a # (<>) :: ReadP (a -> b) -> ReadP a -> ReadP b # liftA2 :: (a -> b -> c) -> ReadP a -> ReadP b -> ReadP c # (>) :: ReadP a -> ReadP b -> ReadP b # (<*) :: ReadP a -> ReadP b -> ReadP a #
Applicative NonEmpty	Since: base-4.9.0.0
Instance details Defined in GHC.Base Methods pure :: a -> NonEmpty a # (<>) :: NonEmpty (a -> b) -> NonEmpty a -> NonEmpty b # liftA2 :: (a -> b -> c) -> NonEmpty a -> NonEmpty b -> NonEmpty c # (>) :: NonEmpty a -> NonEmpty b -> NonEmpty b # (<*) :: NonEmpty a -> NonEmpty b -> NonEmpty a #
Applicative Seq	Since: containers-0.5.4
Instance details Defined in Data.Sequence.Internal Methods pure :: a -> Seq a # (<>) :: Seq (a -> b) -> Seq a -> Seq b # liftA2 :: (a -> b -> c) -> Seq a -> Seq b -> Seq c # (>) :: Seq a -> Seq b -> Seq b # (<*) :: Seq a -> Seq b -> Seq a #
Applicative Vector
Instance details Defined in Data.Vector Methods pure :: a -> Vector a # (<>) :: Vector (a -> b) -> Vector a -> Vector b # liftA2 :: (a -> b -> c) -> Vector a -> Vector b -> Vector c # (>) :: Vector a -> Vector b -> Vector b # (<*) :: Vector a -> Vector b -> Vector a #
Applicative P	Since: base-4.5.0.0
Instance details Defined in Text.ParserCombinators.ReadP Methods pure :: a -> P a # (<>) :: P (a -> b) -> P a -> P b # liftA2 :: (a -> b -> c) -> P a -> P b -> P c # (>) :: P a -> P b -> P b # (<*) :: P a -> P b -> P a #
Applicative (Either e)	Since: base-3.0
Instance details Defined in Data.Either Methods pure :: a -> Either e a # (<>) :: Either e (a -> b) -> Either e a -> Either e b # liftA2 :: (a -> b -> c) -> Either e a -> Either e b -> Either e c # (>) :: Either e a -> Either e b -> Either e b # (<*) :: Either e a -> Either e b -> Either e a #
Applicative (U1 :: Type -> Type)	Since: base-4.9.0.0
Instance details Defined in GHC.Generics Methods pure :: a -> U1 a # (<>) :: U1 (a -> b) -> U1 a -> U1 b # liftA2 :: (a -> b -> c) -> U1 a -> U1 b -> U1 c # (>) :: U1 a -> U1 b -> U1 b # (<*) :: U1 a -> U1 b -> U1 a #
Monoid a => Applicative ((,) a)	For tuples, the `Monoid` constraint on `a` determines how the first values merge. For example, `String`s concatenate: ("hello ", (+15)) <> ("world!", 2002) ("hello world!",2017) Since: base-2.1*
Instance details Defined in GHC.Base Methods pure :: a0 -> (a, a0) # (<>) :: (a, a0 -> b) -> (a, a0) -> (a, b) # liftA2 :: (a0 -> b -> c) -> (a, a0) -> (a, b) -> (a, c) # (>) :: (a, a0) -> (a, b) -> (a, b) # (<*) :: (a, a0) -> (a, b) -> (a, a0) #
Monad m => Applicative (WrappedMonad m)	Since: base-2.1
Instance details Defined in Control.Applicative Methods pure :: a -> WrappedMonad m a # (<>) :: WrappedMonad m (a -> b) -> WrappedMonad m a -> WrappedMonad m b # liftA2 :: (a -> b -> c) -> WrappedMonad m a -> WrappedMonad m b -> WrappedMonad m c # (>) :: WrappedMonad m a -> WrappedMonad m b -> WrappedMonad m b # (<*) :: WrappedMonad m a -> WrappedMonad m b -> WrappedMonad m a #
Arrow a => Applicative (ArrowMonad a)	Since: base-4.6.0.0
Instance details Defined in Control.Arrow Methods pure :: a0 -> ArrowMonad a a0 # (<>) :: ArrowMonad a (a0 -> b) -> ArrowMonad a a0 -> ArrowMonad a b # liftA2 :: (a0 -> b -> c) -> ArrowMonad a a0 -> ArrowMonad a b -> ArrowMonad a c # (>) :: ArrowMonad a a0 -> ArrowMonad a b -> ArrowMonad a b # (<*) :: ArrowMonad a a0 -> ArrowMonad a b -> ArrowMonad a a0 #
Applicative (Proxy :: Type -> Type)	Since: base-4.7.0.0
Instance details Defined in Data.Proxy Methods pure :: a -> Proxy a # (<>) :: Proxy (a -> b) -> Proxy a -> Proxy b # liftA2 :: (a -> b -> c) -> Proxy a -> Proxy b -> Proxy c # (>) :: Proxy a -> Proxy b -> Proxy b # (<*) :: Proxy a -> Proxy b -> Proxy a #
(Functor m, Monad m) => Applicative (MaybeT m)
Instance details Defined in Control.Monad.Trans.Maybe Methods pure :: a -> MaybeT m a # (<>) :: MaybeT m (a -> b) -> MaybeT m a -> MaybeT m b # liftA2 :: (a -> b -> c) -> MaybeT m a -> MaybeT m b -> MaybeT m c # (>) :: MaybeT m a -> MaybeT m b -> MaybeT m b # (<*) :: MaybeT m a -> MaybeT m b -> MaybeT m a #
Applicative f => Applicative (Rec1 f)	Since: base-4.9.0.0
Instance details Defined in GHC.Generics Methods pure :: a -> Rec1 f a # (<>) :: Rec1 f (a -> b) -> Rec1 f a -> Rec1 f b # liftA2 :: (a -> b -> c) -> Rec1 f a -> Rec1 f b -> Rec1 f c # (>) :: Rec1 f a -> Rec1 f b -> Rec1 f b # (<*) :: Rec1 f a -> Rec1 f b -> Rec1 f a #
Arrow a => Applicative (WrappedArrow a b)	Since: base-2.1
Instance details Defined in Control.Applicative Methods pure :: a0 -> WrappedArrow a b a0 # (<>) :: WrappedArrow a b (a0 -> b0) -> WrappedArrow a b a0 -> WrappedArrow a b b0 # liftA2 :: (a0 -> b0 -> c) -> WrappedArrow a b a0 -> WrappedArrow a b b0 -> WrappedArrow a b c # (>) :: WrappedArrow a b a0 -> WrappedArrow a b b0 -> WrappedArrow a b b0 # (<*) :: WrappedArrow a b a0 -> WrappedArrow a b b0 -> WrappedArrow a b a0 #
Monoid m => Applicative (Const m :: Type -> Type)	Since: base-2.0.1
Instance details Defined in Data.Functor.Const Methods pure :: a -> Const m a # (<>) :: Const m (a -> b) -> Const m a -> Const m b # liftA2 :: (a -> b -> c) -> Const m a -> Const m b -> Const m c # (>) :: Const m a -> Const m b -> Const m b # (<*) :: Const m a -> Const m b -> Const m a #
Applicative f => Applicative (Ap f)	Since: base-4.12.0.0
Instance details Defined in Data.Monoid Methods pure :: a -> Ap f a # (<>) :: Ap f (a -> b) -> Ap f a -> Ap f b # liftA2 :: (a -> b -> c) -> Ap f a -> Ap f b -> Ap f c # (>) :: Ap f a -> Ap f b -> Ap f b # (<*) :: Ap f a -> Ap f b -> Ap f a #
Applicative f => Applicative (Alt f)	Since: base-4.8.0.0
Instance details Defined in Data.Semigroup.Internal Methods pure :: a -> Alt f a # (<>) :: Alt f (a -> b) -> Alt f a -> Alt f b # liftA2 :: (a -> b -> c) -> Alt f a -> Alt f b -> Alt f c # (>) :: Alt f a -> Alt f b -> Alt f b # (<*) :: Alt f a -> Alt f b -> Alt f a #
(Applicative f, Monad f) => Applicative (WhenMissing f x)	Equivalent to `ReaderT k (ReaderT x (MaybeT f))`. Since: containers-0.5.9
Instance details Defined in Data.IntMap.Internal Methods pure :: a -> WhenMissing f x a # (<>) :: WhenMissing f x (a -> b) -> WhenMissing f x a -> WhenMissing f x b # liftA2 :: (a -> b -> c) -> WhenMissing f x a -> WhenMissing f x b -> WhenMissing f x c # (>) :: WhenMissing f x a -> WhenMissing f x b -> WhenMissing f x b # (<*) :: WhenMissing f x a -> WhenMissing f x b -> WhenMissing f x a #
(Functor m, Monad m) => Applicative (ExceptT e m)
Instance details Defined in Control.Monad.Trans.Except Methods pure :: a -> ExceptT e m a # (<>) :: ExceptT e m (a -> b) -> ExceptT e m a -> ExceptT e m b # liftA2 :: (a -> b -> c) -> ExceptT e m a -> ExceptT e m b -> ExceptT e m c # (>) :: ExceptT e m a -> ExceptT e m b -> ExceptT e m b # (<*) :: ExceptT e m a -> ExceptT e m b -> ExceptT e m a #
Applicative m => Applicative (IdentityT m)
Instance details Defined in Control.Monad.Trans.Identity Methods pure :: a -> IdentityT m a # (<>) :: IdentityT m (a -> b) -> IdentityT m a -> IdentityT m b # liftA2 :: (a -> b -> c) -> IdentityT m a -> IdentityT m b -> IdentityT m c # (>) :: IdentityT m a -> IdentityT m b -> IdentityT m b # (<*) :: IdentityT m a -> IdentityT m b -> IdentityT m a #
(Functor m, Monad m) => Applicative (ErrorT e m)
Instance details Defined in Control.Monad.Trans.Error Methods pure :: a -> ErrorT e m a # (<>) :: ErrorT e m (a -> b) -> ErrorT e m a -> ErrorT e m b # liftA2 :: (a -> b -> c) -> ErrorT e m a -> ErrorT e m b -> ErrorT e m c # (>) :: ErrorT e m a -> ErrorT e m b -> ErrorT e m b # (<*) :: ErrorT e m a -> ErrorT e m b -> ErrorT e m a #
(Functor m, Monad m) => Applicative (StateT s m)
Instance details Defined in Control.Monad.Trans.State.Strict Methods pure :: a -> StateT s m a # (<>) :: StateT s m (a -> b) -> StateT s m a -> StateT s m b # liftA2 :: (a -> b -> c) -> StateT s m a -> StateT s m b -> StateT s m c # (>) :: StateT s m a -> StateT s m b -> StateT s m b # (<*) :: StateT s m a -> StateT s m b -> StateT s m a #
Applicative (Bazaar a b)
Instance details Defined in Lens.Micro Methods pure :: a0 -> Bazaar a b a0 # (<>) :: Bazaar a b (a0 -> b0) -> Bazaar a b a0 -> Bazaar a b b0 # liftA2 :: (a0 -> b0 -> c) -> Bazaar a b a0 -> Bazaar a b b0 -> Bazaar a b c # (>) :: Bazaar a b a0 -> Bazaar a b b0 -> Bazaar a b b0 # (<*) :: Bazaar a b a0 -> Bazaar a b b0 -> Bazaar a b a0 #
(Functor m, Monad m) => Applicative (StateT s m)
Instance details Defined in Lens.Micro Methods pure :: a -> StateT s m a # (<>) :: StateT s m (a -> b) -> StateT s m a -> StateT s m b # liftA2 :: (a -> b -> c) -> StateT s m a -> StateT s m b -> StateT s m c # (>) :: StateT s m a -> StateT s m b -> StateT s m b # (<*) :: StateT s m a -> StateT s m b -> StateT s m a #
Applicative ((->) a :: Type -> Type)	Since: base-2.1
Instance details Defined in GHC.Base Methods pure :: a0 -> a -> a0 # (<>) :: (a -> (a0 -> b)) -> (a -> a0) -> a -> b # liftA2 :: (a0 -> b -> c) -> (a -> a0) -> (a -> b) -> a -> c # (>) :: (a -> a0) -> (a -> b) -> a -> b # (<*) :: (a -> a0) -> (a -> b) -> a -> a0 #
Monoid c => Applicative (K1 i c :: Type -> Type)	Since: base-4.12.0.0
Instance details Defined in GHC.Generics Methods pure :: a -> K1 i c a # (<>) :: K1 i c (a -> b) -> K1 i c a -> K1 i c b # liftA2 :: (a -> b -> c0) -> K1 i c a -> K1 i c b -> K1 i c c0 # (>) :: K1 i c a -> K1 i c b -> K1 i c b # (<*) :: K1 i c a -> K1 i c b -> K1 i c a #
(Applicative f, Applicative g) => Applicative (f :*: g)	Since: base-4.9.0.0
Instance details Defined in GHC.Generics Methods pure :: a -> (f :: g) a # (<>) :: (f :: g) (a -> b) -> (f :: g) a -> (f :: g) b # liftA2 :: (a -> b -> c) -> (f :: g) a -> (f :: g) b -> (f :: g) c # (>) :: (f :: g) a -> (f :: g) b -> (f :: g) b # (<) :: (f :: g) a -> (f :: g) b -> (f :: g) a #
(Monad f, Applicative f) => Applicative (WhenMatched f x y)	Equivalent to `ReaderT Key (ReaderT x (ReaderT y (MaybeT f)))` Since: containers-0.5.9
Instance details Defined in Data.IntMap.Internal Methods pure :: a -> WhenMatched f x y a # (<>) :: WhenMatched f x y (a -> b) -> WhenMatched f x y a -> WhenMatched f x y b # liftA2 :: (a -> b -> c) -> WhenMatched f x y a -> WhenMatched f x y b -> WhenMatched f x y c # (>) :: WhenMatched f x y a -> WhenMatched f x y b -> WhenMatched f x y b # (<*) :: WhenMatched f x y a -> WhenMatched f x y b -> WhenMatched f x y a #
(Applicative f, Monad f) => Applicative (WhenMissing f k x)	Equivalent to `ReaderT k (ReaderT x (MaybeT f))` . Since: containers-0.5.9
Instance details Defined in Data.Map.Internal Methods pure :: a -> WhenMissing f k x a # (<>) :: WhenMissing f k x (a -> b) -> WhenMissing f k x a -> WhenMissing f k x b # liftA2 :: (a -> b -> c) -> WhenMissing f k x a -> WhenMissing f k x b -> WhenMissing f k x c # (>) :: WhenMissing f k x a -> WhenMissing f k x b -> WhenMissing f k x b # (<*) :: WhenMissing f k x a -> WhenMissing f k x b -> WhenMissing f k x a #
Applicative m => Applicative (ReaderT r m)
Instance details Defined in Control.Monad.Trans.Reader Methods pure :: a -> ReaderT r m a # (<>) :: ReaderT r m (a -> b) -> ReaderT r m a -> ReaderT r m b # liftA2 :: (a -> b -> c) -> ReaderT r m a -> ReaderT r m b -> ReaderT r m c # (>) :: ReaderT r m a -> ReaderT r m b -> ReaderT r m b # (<*) :: ReaderT r m a -> ReaderT r m b -> ReaderT r m a #
Applicative f => Applicative (M1 i c f)	Since: base-4.9.0.0
Instance details Defined in GHC.Generics Methods pure :: a -> M1 i c f a # (<>) :: M1 i c f (a -> b) -> M1 i c f a -> M1 i c f b # liftA2 :: (a -> b -> c0) -> M1 i c f a -> M1 i c f b -> M1 i c f c0 # (>) :: M1 i c f a -> M1 i c f b -> M1 i c f b # (<*) :: M1 i c f a -> M1 i c f b -> M1 i c f a #
(Applicative f, Applicative g) => Applicative (f :.: g)	Since: base-4.9.0.0
Instance details Defined in GHC.Generics Methods pure :: a -> (f :.: g) a # (<>) :: (f :.: g) (a -> b) -> (f :.: g) a -> (f :.: g) b # liftA2 :: (a -> b -> c) -> (f :.: g) a -> (f :.: g) b -> (f :.: g) c # (>) :: (f :.: g) a -> (f :.: g) b -> (f :.: g) b # (<*) :: (f :.: g) a -> (f :.: g) b -> (f :.: g) a #
(Applicative f, Applicative g) => Applicative (Compose f g)	Since: base-4.9.0.0
Instance details Defined in Data.Functor.Compose Methods pure :: a -> Compose f g a # (<>) :: Compose f g (a -> b) -> Compose f g a -> Compose f g b # liftA2 :: (a -> b -> c) -> Compose f g a -> Compose f g b -> Compose f g c # (>) :: Compose f g a -> Compose f g b -> Compose f g b # (<*) :: Compose f g a -> Compose f g b -> Compose f g a #
(Monad f, Applicative f) => Applicative (WhenMatched f k x y)	Equivalent to `ReaderT k (ReaderT x (ReaderT y (MaybeT f)))` Since: containers-0.5.9
Instance details Defined in Data.Map.Internal Methods pure :: a -> WhenMatched f k x y a # (<>) :: WhenMatched f k x y (a -> b) -> WhenMatched f k x y a -> WhenMatched f k x y b # liftA2 :: (a -> b -> c) -> WhenMatched f k x y a -> WhenMatched f k x y b -> WhenMatched f k x y c # (>) :: WhenMatched f k x y a -> WhenMatched f k x y b -> WhenMatched f k x y b # (<*) :: WhenMatched f k x y a -> WhenMatched f k x y b -> WhenMatched f k x y a #

class Foldable (t :: Type -> Type) #

Data structures that can be folded.

For example, given a data type

data Tree a = Empty | Leaf a | Node (Tree a) a (Tree a)

a suitable instance would be

instance Foldable Tree where
   foldMap f Empty = mempty
   foldMap f (Leaf x) = f x
   foldMap f (Node l k r) = foldMap f l `mappend` f k `mappend` foldMap f r

This is suitable even for abstract types, as the monoid is assumed to satisfy the monoid laws. Alternatively, one could define foldr:

instance Foldable Tree where
   foldr f z Empty = z
   foldr f z (Leaf x) = f x z
   foldr f z (Node l k r) = foldr f (f k (foldr f z r)) l

Foldable instances are expected to satisfy the following laws:

foldr f z t = appEndo (foldMap (Endo . f) t ) z

foldl f z t = appEndo (getDual (foldMap (Dual . Endo . flip f) t)) z

fold = foldMap id

length = getSum . foldMap (Sum . const  1)

sum, product, maximum, and minimum should all be essentially equivalent to foldMap forms, such as

sum = getSum . foldMap Sum

but may be less defined.

If the type is also a Functor instance, it should satisfy

foldMap f = fold . fmap f

which implies that

foldMap f . fmap g = foldMap (f . g)

Minimal complete definition

foldMap | foldr

Instances

Foldable []	Since: base-2.1
Instance details Defined in Data.Foldable Methods fold :: Monoid m => [m] -> m # foldMap :: Monoid m => (a -> m) -> [a] -> m # foldr :: (a -> b -> b) -> b -> [a] -> b # foldr' :: (a -> b -> b) -> b -> [a] -> b # foldl :: (b -> a -> b) -> b -> [a] -> b # foldl' :: (b -> a -> b) -> b -> [a] -> b # foldr1 :: (a -> a -> a) -> [a] -> a # foldl1 :: (a -> a -> a) -> [a] -> a # toList :: [a] -> [a] # null :: [a] -> Bool # length :: [a] -> Int # elem :: Eq a => a -> [a] -> Bool # maximum :: Ord a => [a] -> a # minimum :: Ord a => [a] -> a # sum :: Num a => [a] -> a # product :: Num a => [a] -> a #
Foldable Maybe	Since: base-2.1
Instance details Defined in Data.Foldable Methods fold :: Monoid m => Maybe m -> m # foldMap :: Monoid m => (a -> m) -> Maybe a -> m # foldr :: (a -> b -> b) -> b -> Maybe a -> b # foldr' :: (a -> b -> b) -> b -> Maybe a -> b # foldl :: (b -> a -> b) -> b -> Maybe a -> b # foldl' :: (b -> a -> b) -> b -> Maybe a -> b # foldr1 :: (a -> a -> a) -> Maybe a -> a # foldl1 :: (a -> a -> a) -> Maybe a -> a # toList :: Maybe a -> [a] # null :: Maybe a -> Bool # length :: Maybe a -> Int # elem :: Eq a => a -> Maybe a -> Bool # maximum :: Ord a => Maybe a -> a # minimum :: Ord a => Maybe a -> a # sum :: Num a => Maybe a -> a # product :: Num a => Maybe a -> a #
Foldable Par1	Since: base-4.9.0.0
Instance details Defined in Data.Foldable Methods fold :: Monoid m => Par1 m -> m # foldMap :: Monoid m => (a -> m) -> Par1 a -> m # foldr :: (a -> b -> b) -> b -> Par1 a -> b # foldr' :: (a -> b -> b) -> b -> Par1 a -> b # foldl :: (b -> a -> b) -> b -> Par1 a -> b # foldl' :: (b -> a -> b) -> b -> Par1 a -> b # foldr1 :: (a -> a -> a) -> Par1 a -> a # foldl1 :: (a -> a -> a) -> Par1 a -> a # toList :: Par1 a -> [a] # null :: Par1 a -> Bool # length :: Par1 a -> Int # elem :: Eq a => a -> Par1 a -> Bool # maximum :: Ord a => Par1 a -> a # minimum :: Ord a => Par1 a -> a # sum :: Num a => Par1 a -> a # product :: Num a => Par1 a -> a #
Foldable Min	Since: base-4.9.0.0
Instance details Defined in Data.Semigroup Methods fold :: Monoid m => Min m -> m # foldMap :: Monoid m => (a -> m) -> Min a -> m # foldr :: (a -> b -> b) -> b -> Min a -> b # foldr' :: (a -> b -> b) -> b -> Min a -> b # foldl :: (b -> a -> b) -> b -> Min a -> b # foldl' :: (b -> a -> b) -> b -> Min a -> b # foldr1 :: (a -> a -> a) -> Min a -> a # foldl1 :: (a -> a -> a) -> Min a -> a # toList :: Min a -> [a] # null :: Min a -> Bool # length :: Min a -> Int # elem :: Eq a => a -> Min a -> Bool # maximum :: Ord a => Min a -> a # minimum :: Ord a => Min a -> a # sum :: Num a => Min a -> a # product :: Num a => Min a -> a #
Foldable Max	Since: base-4.9.0.0
Instance details Defined in Data.Semigroup Methods fold :: Monoid m => Max m -> m # foldMap :: Monoid m => (a -> m) -> Max a -> m # foldr :: (a -> b -> b) -> b -> Max a -> b # foldr' :: (a -> b -> b) -> b -> Max a -> b # foldl :: (b -> a -> b) -> b -> Max a -> b # foldl' :: (b -> a -> b) -> b -> Max a -> b # foldr1 :: (a -> a -> a) -> Max a -> a # foldl1 :: (a -> a -> a) -> Max a -> a # toList :: Max a -> [a] # null :: Max a -> Bool # length :: Max a -> Int # elem :: Eq a => a -> Max a -> Bool # maximum :: Ord a => Max a -> a # minimum :: Ord a => Max a -> a # sum :: Num a => Max a -> a # product :: Num a => Max a -> a #
Foldable First	Since: base-4.9.0.0
Instance details Defined in Data.Semigroup Methods fold :: Monoid m => First m -> m # foldMap :: Monoid m => (a -> m) -> First a -> m # foldr :: (a -> b -> b) -> b -> First a -> b # foldr' :: (a -> b -> b) -> b -> First a -> b # foldl :: (b -> a -> b) -> b -> First a -> b # foldl' :: (b -> a -> b) -> b -> First a -> b # foldr1 :: (a -> a -> a) -> First a -> a # foldl1 :: (a -> a -> a) -> First a -> a # toList :: First a -> [a] # null :: First a -> Bool # length :: First a -> Int # elem :: Eq a => a -> First a -> Bool # maximum :: Ord a => First a -> a # minimum :: Ord a => First a -> a # sum :: Num a => First a -> a # product :: Num a => First a -> a #
Foldable Last	Since: base-4.9.0.0
Instance details Defined in Data.Semigroup Methods fold :: Monoid m => Last m -> m # foldMap :: Monoid m => (a -> m) -> Last a -> m # foldr :: (a -> b -> b) -> b -> Last a -> b # foldr' :: (a -> b -> b) -> b -> Last a -> b # foldl :: (b -> a -> b) -> b -> Last a -> b # foldl' :: (b -> a -> b) -> b -> Last a -> b # foldr1 :: (a -> a -> a) -> Last a -> a # foldl1 :: (a -> a -> a) -> Last a -> a # toList :: Last a -> [a] # null :: Last a -> Bool # length :: Last a -> Int # elem :: Eq a => a -> Last a -> Bool # maximum :: Ord a => Last a -> a # minimum :: Ord a => Last a -> a # sum :: Num a => Last a -> a # product :: Num a => Last a -> a #
Foldable Option	Since: base-4.9.0.0
Instance details Defined in Data.Semigroup Methods fold :: Monoid m => Option m -> m # foldMap :: Monoid m => (a -> m) -> Option a -> m # foldr :: (a -> b -> b) -> b -> Option a -> b # foldr' :: (a -> b -> b) -> b -> Option a -> b # foldl :: (b -> a -> b) -> b -> Option a -> b # foldl' :: (b -> a -> b) -> b -> Option a -> b # foldr1 :: (a -> a -> a) -> Option a -> a # foldl1 :: (a -> a -> a) -> Option a -> a # toList :: Option a -> [a] # null :: Option a -> Bool # length :: Option a -> Int # elem :: Eq a => a -> Option a -> Bool # maximum :: Ord a => Option a -> a # minimum :: Ord a => Option a -> a # sum :: Num a => Option a -> a # product :: Num a => Option a -> a #
Foldable ZipList	Since: base-4.9.0.0
Instance details Defined in Control.Applicative Methods fold :: Monoid m => ZipList m -> m # foldMap :: Monoid m => (a -> m) -> ZipList a -> m # foldr :: (a -> b -> b) -> b -> ZipList a -> b # foldr' :: (a -> b -> b) -> b -> ZipList a -> b # foldl :: (b -> a -> b) -> b -> ZipList a -> b # foldl' :: (b -> a -> b) -> b -> ZipList a -> b # foldr1 :: (a -> a -> a) -> ZipList a -> a # foldl1 :: (a -> a -> a) -> ZipList a -> a # toList :: ZipList a -> [a] # null :: ZipList a -> Bool # length :: ZipList a -> Int # elem :: Eq a => a -> ZipList a -> Bool # maximum :: Ord a => ZipList a -> a # minimum :: Ord a => ZipList a -> a # sum :: Num a => ZipList a -> a # product :: Num a => ZipList a -> a #
Foldable Identity	Since: base-4.8.0.0
Instance details Defined in Data.Functor.Identity Methods fold :: Monoid m => Identity m -> m # foldMap :: Monoid m => (a -> m) -> Identity a -> m # foldr :: (a -> b -> b) -> b -> Identity a -> b # foldr' :: (a -> b -> b) -> b -> Identity a -> b # foldl :: (b -> a -> b) -> b -> Identity a -> b # foldl' :: (b -> a -> b) -> b -> Identity a -> b # foldr1 :: (a -> a -> a) -> Identity a -> a # foldl1 :: (a -> a -> a) -> Identity a -> a # toList :: Identity a -> [a] # null :: Identity a -> Bool # length :: Identity a -> Int # elem :: Eq a => a -> Identity a -> Bool # maximum :: Ord a => Identity a -> a # minimum :: Ord a => Identity a -> a # sum :: Num a => Identity a -> a # product :: Num a => Identity a -> a #
Foldable First	Since: base-4.8.0.0
Instance details Defined in Data.Foldable Methods fold :: Monoid m => First m -> m # foldMap :: Monoid m => (a -> m) -> First a -> m # foldr :: (a -> b -> b) -> b -> First a -> b # foldr' :: (a -> b -> b) -> b -> First a -> b # foldl :: (b -> a -> b) -> b -> First a -> b # foldl' :: (b -> a -> b) -> b -> First a -> b # foldr1 :: (a -> a -> a) -> First a -> a # foldl1 :: (a -> a -> a) -> First a -> a # toList :: First a -> [a] # null :: First a -> Bool # length :: First a -> Int # elem :: Eq a => a -> First a -> Bool # maximum :: Ord a => First a -> a # minimum :: Ord a => First a -> a # sum :: Num a => First a -> a # product :: Num a => First a -> a #
Foldable Last	Since: base-4.8.0.0
Instance details Defined in Data.Foldable Methods fold :: Monoid m => Last m -> m # foldMap :: Monoid m => (a -> m) -> Last a -> m # foldr :: (a -> b -> b) -> b -> Last a -> b # foldr' :: (a -> b -> b) -> b -> Last a -> b # foldl :: (b -> a -> b) -> b -> Last a -> b # foldl' :: (b -> a -> b) -> b -> Last a -> b # foldr1 :: (a -> a -> a) -> Last a -> a # foldl1 :: (a -> a -> a) -> Last a -> a # toList :: Last a -> [a] # null :: Last a -> Bool # length :: Last a -> Int # elem :: Eq a => a -> Last a -> Bool # maximum :: Ord a => Last a -> a # minimum :: Ord a => Last a -> a # sum :: Num a => Last a -> a # product :: Num a => Last a -> a #
Foldable Dual	Since: base-4.8.0.0
Instance details Defined in Data.Foldable Methods fold :: Monoid m => Dual m -> m # foldMap :: Monoid m => (a -> m) -> Dual a -> m # foldr :: (a -> b -> b) -> b -> Dual a -> b # foldr' :: (a -> b -> b) -> b -> Dual a -> b # foldl :: (b -> a -> b) -> b -> Dual a -> b # foldl' :: (b -> a -> b) -> b -> Dual a -> b # foldr1 :: (a -> a -> a) -> Dual a -> a # foldl1 :: (a -> a -> a) -> Dual a -> a # toList :: Dual a -> [a] # null :: Dual a -> Bool # length :: Dual a -> Int # elem :: Eq a => a -> Dual a -> Bool # maximum :: Ord a => Dual a -> a # minimum :: Ord a => Dual a -> a # sum :: Num a => Dual a -> a # product :: Num a => Dual a -> a #
Foldable Sum	Since: base-4.8.0.0
Instance details Defined in Data.Foldable Methods fold :: Monoid m => Sum m -> m # foldMap :: Monoid m => (a -> m) -> Sum a -> m # foldr :: (a -> b -> b) -> b -> Sum a -> b # foldr' :: (a -> b -> b) -> b -> Sum a -> b # foldl :: (b -> a -> b) -> b -> Sum a -> b # foldl' :: (b -> a -> b) -> b -> Sum a -> b # foldr1 :: (a -> a -> a) -> Sum a -> a # foldl1 :: (a -> a -> a) -> Sum a -> a # toList :: Sum a -> [a] # null :: Sum a -> Bool # length :: Sum a -> Int # elem :: Eq a => a -> Sum a -> Bool # maximum :: Ord a => Sum a -> a # minimum :: Ord a => Sum a -> a # sum :: Num a => Sum a -> a # product :: Num a => Sum a -> a #
Foldable Product	Since: base-4.8.0.0
Instance details Defined in Data.Foldable Methods fold :: Monoid m => Product m -> m # foldMap :: Monoid m => (a -> m) -> Product a -> m # foldr :: (a -> b -> b) -> b -> Product a -> b # foldr' :: (a -> b -> b) -> b -> Product a -> b # foldl :: (b -> a -> b) -> b -> Product a -> b # foldl' :: (b -> a -> b) -> b -> Product a -> b # foldr1 :: (a -> a -> a) -> Product a -> a # foldl1 :: (a -> a -> a) -> Product a -> a # toList :: Product a -> [a] # null :: Product a -> Bool # length :: Product a -> Int # elem :: Eq a => a -> Product a -> Bool # maximum :: Ord a => Product a -> a # minimum :: Ord a => Product a -> a # sum :: Num a => Product a -> a # product :: Num a => Product a -> a #
Foldable Down	Since: base-4.12.0.0
Instance details Defined in Data.Foldable Methods fold :: Monoid m => Down m -> m # foldMap :: Monoid m => (a -> m) -> Down a -> m # foldr :: (a -> b -> b) -> b -> Down a -> b # foldr' :: (a -> b -> b) -> b -> Down a -> b # foldl :: (b -> a -> b) -> b -> Down a -> b # foldl' :: (b -> a -> b) -> b -> Down a -> b # foldr1 :: (a -> a -> a) -> Down a -> a # foldl1 :: (a -> a -> a) -> Down a -> a # toList :: Down a -> [a] # null :: Down a -> Bool # length :: Down a -> Int # elem :: Eq a => a -> Down a -> Bool # maximum :: Ord a => Down a -> a # minimum :: Ord a => Down a -> a # sum :: Num a => Down a -> a # product :: Num a => Down a -> a #
Foldable NonEmpty	Since: base-4.9.0.0
Instance details Defined in Data.Foldable Methods fold :: Monoid m => NonEmpty m -> m # foldMap :: Monoid m => (a -> m) -> NonEmpty a -> m # foldr :: (a -> b -> b) -> b -> NonEmpty a -> b # foldr' :: (a -> b -> b) -> b -> NonEmpty a -> b # foldl :: (b -> a -> b) -> b -> NonEmpty a -> b # foldl' :: (b -> a -> b) -> b -> NonEmpty a -> b # foldr1 :: (a -> a -> a) -> NonEmpty a -> a # foldl1 :: (a -> a -> a) -> NonEmpty a -> a # toList :: NonEmpty a -> [a] # null :: NonEmpty a -> Bool # length :: NonEmpty a -> Int # elem :: Eq a => a -> NonEmpty a -> Bool # maximum :: Ord a => NonEmpty a -> a # minimum :: Ord a => NonEmpty a -> a # sum :: Num a => NonEmpty a -> a # product :: Num a => NonEmpty a -> a #
Foldable IntMap
Instance details Defined in Data.IntMap.Internal Methods fold :: Monoid m => IntMap m -> m # foldMap :: Monoid m => (a -> m) -> IntMap a -> m # foldr :: (a -> b -> b) -> b -> IntMap a -> b # foldr' :: (a -> b -> b) -> b -> IntMap a -> b # foldl :: (b -> a -> b) -> b -> IntMap a -> b # foldl' :: (b -> a -> b) -> b -> IntMap a -> b # foldr1 :: (a -> a -> a) -> IntMap a -> a # foldl1 :: (a -> a -> a) -> IntMap a -> a # toList :: IntMap a -> [a] # null :: IntMap a -> Bool # length :: IntMap a -> Int # elem :: Eq a => a -> IntMap a -> Bool # maximum :: Ord a => IntMap a -> a # minimum :: Ord a => IntMap a -> a # sum :: Num a => IntMap a -> a # product :: Num a => IntMap a -> a #
Foldable Seq
Instance details Defined in Data.Sequence.Internal Methods fold :: Monoid m => Seq m -> m # foldMap :: Monoid m => (a -> m) -> Seq a -> m # foldr :: (a -> b -> b) -> b -> Seq a -> b # foldr' :: (a -> b -> b) -> b -> Seq a -> b # foldl :: (b -> a -> b) -> b -> Seq a -> b # foldl' :: (b -> a -> b) -> b -> Seq a -> b # foldr1 :: (a -> a -> a) -> Seq a -> a # foldl1 :: (a -> a -> a) -> Seq a -> a # toList :: Seq a -> [a] # null :: Seq a -> Bool # length :: Seq a -> Int # elem :: Eq a => a -> Seq a -> Bool # maximum :: Ord a => Seq a -> a # minimum :: Ord a => Seq a -> a # sum :: Num a => Seq a -> a # product :: Num a => Seq a -> a #
Foldable FingerTree
Instance details Defined in Data.Sequence.Internal Methods fold :: Monoid m => FingerTree m -> m # foldMap :: Monoid m => (a -> m) -> FingerTree a -> m # foldr :: (a -> b -> b) -> b -> FingerTree a -> b # foldr' :: (a -> b -> b) -> b -> FingerTree a -> b # foldl :: (b -> a -> b) -> b -> FingerTree a -> b # foldl' :: (b -> a -> b) -> b -> FingerTree a -> b # foldr1 :: (a -> a -> a) -> FingerTree a -> a # foldl1 :: (a -> a -> a) -> FingerTree a -> a # toList :: FingerTree a -> [a] # null :: FingerTree a -> Bool # length :: FingerTree a -> Int # elem :: Eq a => a -> FingerTree a -> Bool # maximum :: Ord a => FingerTree a -> a # minimum :: Ord a => FingerTree a -> a # sum :: Num a => FingerTree a -> a # product :: Num a => FingerTree a -> a #
Foldable Digit
Instance details Defined in Data.Sequence.Internal Methods fold :: Monoid m => Digit m -> m # foldMap :: Monoid m => (a -> m) -> Digit a -> m # foldr :: (a -> b -> b) -> b -> Digit a -> b # foldr' :: (a -> b -> b) -> b -> Digit a -> b # foldl :: (b -> a -> b) -> b -> Digit a -> b # foldl' :: (b -> a -> b) -> b -> Digit a -> b # foldr1 :: (a -> a -> a) -> Digit a -> a # foldl1 :: (a -> a -> a) -> Digit a -> a # toList :: Digit a -> [a] # null :: Digit a -> Bool # length :: Digit a -> Int # elem :: Eq a => a -> Digit a -> Bool # maximum :: Ord a => Digit a -> a # minimum :: Ord a => Digit a -> a # sum :: Num a => Digit a -> a # product :: Num a => Digit a -> a #
Foldable Node
Instance details Defined in Data.Sequence.Internal Methods fold :: Monoid m => Node m -> m # foldMap :: Monoid m => (a -> m) -> Node a -> m # foldr :: (a -> b -> b) -> b -> Node a -> b # foldr' :: (a -> b -> b) -> b -> Node a -> b # foldl :: (b -> a -> b) -> b -> Node a -> b # foldl' :: (b -> a -> b) -> b -> Node a -> b # foldr1 :: (a -> a -> a) -> Node a -> a # foldl1 :: (a -> a -> a) -> Node a -> a # toList :: Node a -> [a] # null :: Node a -> Bool # length :: Node a -> Int # elem :: Eq a => a -> Node a -> Bool # maximum :: Ord a => Node a -> a # minimum :: Ord a => Node a -> a # sum :: Num a => Node a -> a # product :: Num a => Node a -> a #
Foldable Elem
Instance details Defined in Data.Sequence.Internal Methods fold :: Monoid m => Elem m -> m # foldMap :: Monoid m => (a -> m) -> Elem a -> m # foldr :: (a -> b -> b) -> b -> Elem a -> b # foldr' :: (a -> b -> b) -> b -> Elem a -> b # foldl :: (b -> a -> b) -> b -> Elem a -> b # foldl' :: (b -> a -> b) -> b -> Elem a -> b # foldr1 :: (a -> a -> a) -> Elem a -> a # foldl1 :: (a -> a -> a) -> Elem a -> a # toList :: Elem a -> [a] # null :: Elem a -> Bool # length :: Elem a -> Int # elem :: Eq a => a -> Elem a -> Bool # maximum :: Ord a => Elem a -> a # minimum :: Ord a => Elem a -> a # sum :: Num a => Elem a -> a # product :: Num a => Elem a -> a #
Foldable ViewL
Instance details Defined in Data.Sequence.Internal Methods fold :: Monoid m => ViewL m -> m # foldMap :: Monoid m => (a -> m) -> ViewL a -> m # foldr :: (a -> b -> b) -> b -> ViewL a -> b # foldr' :: (a -> b -> b) -> b -> ViewL a -> b # foldl :: (b -> a -> b) -> b -> ViewL a -> b # foldl' :: (b -> a -> b) -> b -> ViewL a -> b # foldr1 :: (a -> a -> a) -> ViewL a -> a # foldl1 :: (a -> a -> a) -> ViewL a -> a # toList :: ViewL a -> [a] # null :: ViewL a -> Bool # length :: ViewL a -> Int # elem :: Eq a => a -> ViewL a -> Bool # maximum :: Ord a => ViewL a -> a # minimum :: Ord a => ViewL a -> a # sum :: Num a => ViewL a -> a # product :: Num a => ViewL a -> a #
Foldable ViewR
Instance details Defined in Data.Sequence.Internal Methods fold :: Monoid m => ViewR m -> m # foldMap :: Monoid m => (a -> m) -> ViewR a -> m # foldr :: (a -> b -> b) -> b -> ViewR a -> b # foldr' :: (a -> b -> b) -> b -> ViewR a -> b # foldl :: (b -> a -> b) -> b -> ViewR a -> b # foldl' :: (b -> a -> b) -> b -> ViewR a -> b # foldr1 :: (a -> a -> a) -> ViewR a -> a # foldl1 :: (a -> a -> a) -> ViewR a -> a # toList :: ViewR a -> [a] # null :: ViewR a -> Bool # length :: ViewR a -> Int # elem :: Eq a => a -> ViewR a -> Bool # maximum :: Ord a => ViewR a -> a # minimum :: Ord a => ViewR a -> a # sum :: Num a => ViewR a -> a # product :: Num a => ViewR a -> a #
Foldable Set
Instance details Defined in Data.Set.Internal Methods fold :: Monoid m => Set m -> m # foldMap :: Monoid m => (a -> m) -> Set a -> m # foldr :: (a -> b -> b) -> b -> Set a -> b # foldr' :: (a -> b -> b) -> b -> Set a -> b # foldl :: (b -> a -> b) -> b -> Set a -> b # foldl' :: (b -> a -> b) -> b -> Set a -> b # foldr1 :: (a -> a -> a) -> Set a -> a # foldl1 :: (a -> a -> a) -> Set a -> a # toList :: Set a -> [a] # null :: Set a -> Bool # length :: Set a -> Int # elem :: Eq a => a -> Set a -> Bool # maximum :: Ord a => Set a -> a # minimum :: Ord a => Set a -> a # sum :: Num a => Set a -> a # product :: Num a => Set a -> a #
Foldable Hashed
Instance details Defined in Data.Hashable.Class Methods fold :: Monoid m => Hashed m -> m # foldMap :: Monoid m => (a -> m) -> Hashed a -> m # foldr :: (a -> b -> b) -> b -> Hashed a -> b # foldr' :: (a -> b -> b) -> b -> Hashed a -> b # foldl :: (b -> a -> b) -> b -> Hashed a -> b # foldl' :: (b -> a -> b) -> b -> Hashed a -> b # foldr1 :: (a -> a -> a) -> Hashed a -> a # foldl1 :: (a -> a -> a) -> Hashed a -> a # toList :: Hashed a -> [a] # null :: Hashed a -> Bool # length :: Hashed a -> Int # elem :: Eq a => a -> Hashed a -> Bool # maximum :: Ord a => Hashed a -> a # minimum :: Ord a => Hashed a -> a # sum :: Num a => Hashed a -> a # product :: Num a => Hashed a -> a #
Foldable Vector
Instance details Defined in Data.Vector Methods fold :: Monoid m => Vector m -> m # foldMap :: Monoid m => (a -> m) -> Vector a -> m # foldr :: (a -> b -> b) -> b -> Vector a -> b # foldr' :: (a -> b -> b) -> b -> Vector a -> b # foldl :: (b -> a -> b) -> b -> Vector a -> b # foldl' :: (b -> a -> b) -> b -> Vector a -> b # foldr1 :: (a -> a -> a) -> Vector a -> a # foldl1 :: (a -> a -> a) -> Vector a -> a # toList :: Vector a -> [a] # null :: Vector a -> Bool # length :: Vector a -> Int # elem :: Eq a => a -> Vector a -> Bool # maximum :: Ord a => Vector a -> a # minimum :: Ord a => Vector a -> a # sum :: Num a => Vector a -> a # product :: Num a => Vector a -> a #
Foldable HashSet
Instance details Defined in Data.HashSet.Base Methods fold :: Monoid m => HashSet m -> m # foldMap :: Monoid m => (a -> m) -> HashSet a -> m # foldr :: (a -> b -> b) -> b -> HashSet a -> b # foldr' :: (a -> b -> b) -> b -> HashSet a -> b # foldl :: (b -> a -> b) -> b -> HashSet a -> b # foldl' :: (b -> a -> b) -> b -> HashSet a -> b # foldr1 :: (a -> a -> a) -> HashSet a -> a # foldl1 :: (a -> a -> a) -> HashSet a -> a # toList :: HashSet a -> [a] # null :: HashSet a -> Bool # length :: HashSet a -> Int # elem :: Eq a => a -> HashSet a -> Bool # maximum :: Ord a => HashSet a -> a # minimum :: Ord a => HashSet a -> a # sum :: Num a => HashSet a -> a # product :: Num a => HashSet a -> a #
Foldable (Either a)	Since: base-4.7.0.0
Instance details Defined in Data.Foldable Methods fold :: Monoid m => Either a m -> m # foldMap :: Monoid m => (a0 -> m) -> Either a a0 -> m # foldr :: (a0 -> b -> b) -> b -> Either a a0 -> b # foldr' :: (a0 -> b -> b) -> b -> Either a a0 -> b # foldl :: (b -> a0 -> b) -> b -> Either a a0 -> b # foldl' :: (b -> a0 -> b) -> b -> Either a a0 -> b # foldr1 :: (a0 -> a0 -> a0) -> Either a a0 -> a0 # foldl1 :: (a0 -> a0 -> a0) -> Either a a0 -> a0 # toList :: Either a a0 -> [a0] # null :: Either a a0 -> Bool # length :: Either a a0 -> Int # elem :: Eq a0 => a0 -> Either a a0 -> Bool # maximum :: Ord a0 => Either a a0 -> a0 # minimum :: Ord a0 => Either a a0 -> a0 # sum :: Num a0 => Either a a0 -> a0 # product :: Num a0 => Either a a0 -> a0 #
Foldable (V1 :: Type -> Type)	Since: base-4.9.0.0
Instance details Defined in Data.Foldable Methods fold :: Monoid m => V1 m -> m # foldMap :: Monoid m => (a -> m) -> V1 a -> m # foldr :: (a -> b -> b) -> b -> V1 a -> b # foldr' :: (a -> b -> b) -> b -> V1 a -> b # foldl :: (b -> a -> b) -> b -> V1 a -> b # foldl' :: (b -> a -> b) -> b -> V1 a -> b # foldr1 :: (a -> a -> a) -> V1 a -> a # foldl1 :: (a -> a -> a) -> V1 a -> a # toList :: V1 a -> [a] # null :: V1 a -> Bool # length :: V1 a -> Int # elem :: Eq a => a -> V1 a -> Bool # maximum :: Ord a => V1 a -> a # minimum :: Ord a => V1 a -> a # sum :: Num a => V1 a -> a # product :: Num a => V1 a -> a #
Foldable (U1 :: Type -> Type)	Since: base-4.9.0.0
Instance details Defined in Data.Foldable Methods fold :: Monoid m => U1 m -> m # foldMap :: Monoid m => (a -> m) -> U1 a -> m # foldr :: (a -> b -> b) -> b -> U1 a -> b # foldr' :: (a -> b -> b) -> b -> U1 a -> b # foldl :: (b -> a -> b) -> b -> U1 a -> b # foldl' :: (b -> a -> b) -> b -> U1 a -> b # foldr1 :: (a -> a -> a) -> U1 a -> a # foldl1 :: (a -> a -> a) -> U1 a -> a # toList :: U1 a -> [a] # null :: U1 a -> Bool # length :: U1 a -> Int # elem :: Eq a => a -> U1 a -> Bool # maximum :: Ord a => U1 a -> a # minimum :: Ord a => U1 a -> a # sum :: Num a => U1 a -> a # product :: Num a => U1 a -> a #
Foldable ((,) a)	Since: base-4.7.0.0
Instance details Defined in Data.Foldable Methods fold :: Monoid m => (a, m) -> m # foldMap :: Monoid m => (a0 -> m) -> (a, a0) -> m # foldr :: (a0 -> b -> b) -> b -> (a, a0) -> b # foldr' :: (a0 -> b -> b) -> b -> (a, a0) -> b # foldl :: (b -> a0 -> b) -> b -> (a, a0) -> b # foldl' :: (b -> a0 -> b) -> b -> (a, a0) -> b # foldr1 :: (a0 -> a0 -> a0) -> (a, a0) -> a0 # foldl1 :: (a0 -> a0 -> a0) -> (a, a0) -> a0 # toList :: (a, a0) -> [a0] # null :: (a, a0) -> Bool # length :: (a, a0) -> Int # elem :: Eq a0 => a0 -> (a, a0) -> Bool # maximum :: Ord a0 => (a, a0) -> a0 # minimum :: Ord a0 => (a, a0) -> a0 # sum :: Num a0 => (a, a0) -> a0 # product :: Num a0 => (a, a0) -> a0 #
Foldable (Array i)	Since: base-4.8.0.0
Instance details Defined in Data.Foldable Methods fold :: Monoid m => Array i m -> m # foldMap :: Monoid m => (a -> m) -> Array i a -> m # foldr :: (a -> b -> b) -> b -> Array i a -> b # foldr' :: (a -> b -> b) -> b -> Array i a -> b # foldl :: (b -> a -> b) -> b -> Array i a -> b # foldl' :: (b -> a -> b) -> b -> Array i a -> b # foldr1 :: (a -> a -> a) -> Array i a -> a # foldl1 :: (a -> a -> a) -> Array i a -> a # toList :: Array i a -> [a] # null :: Array i a -> Bool # length :: Array i a -> Int # elem :: Eq a => a -> Array i a -> Bool # maximum :: Ord a => Array i a -> a # minimum :: Ord a => Array i a -> a # sum :: Num a => Array i a -> a # product :: Num a => Array i a -> a #
Foldable (Arg a)	Since: base-4.9.0.0
Instance details Defined in Data.Semigroup Methods fold :: Monoid m => Arg a m -> m # foldMap :: Monoid m => (a0 -> m) -> Arg a a0 -> m # foldr :: (a0 -> b -> b) -> b -> Arg a a0 -> b # foldr' :: (a0 -> b -> b) -> b -> Arg a a0 -> b # foldl :: (b -> a0 -> b) -> b -> Arg a a0 -> b # foldl' :: (b -> a0 -> b) -> b -> Arg a a0 -> b # foldr1 :: (a0 -> a0 -> a0) -> Arg a a0 -> a0 # foldl1 :: (a0 -> a0 -> a0) -> Arg a a0 -> a0 # toList :: Arg a a0 -> [a0] # null :: Arg a a0 -> Bool # length :: Arg a a0 -> Int # elem :: Eq a0 => a0 -> Arg a a0 -> Bool # maximum :: Ord a0 => Arg a a0 -> a0 # minimum :: Ord a0 => Arg a a0 -> a0 # sum :: Num a0 => Arg a a0 -> a0 # product :: Num a0 => Arg a a0 -> a0 #
Foldable (Proxy :: Type -> Type)	Since: base-4.7.0.0
Instance details Defined in Data.Foldable Methods fold :: Monoid m => Proxy m -> m # foldMap :: Monoid m => (a -> m) -> Proxy a -> m # foldr :: (a -> b -> b) -> b -> Proxy a -> b # foldr' :: (a -> b -> b) -> b -> Proxy a -> b # foldl :: (b -> a -> b) -> b -> Proxy a -> b # foldl' :: (b -> a -> b) -> b -> Proxy a -> b # foldr1 :: (a -> a -> a) -> Proxy a -> a # foldl1 :: (a -> a -> a) -> Proxy a -> a # toList :: Proxy a -> [a] # null :: Proxy a -> Bool # length :: Proxy a -> Int # elem :: Eq a => a -> Proxy a -> Bool # maximum :: Ord a => Proxy a -> a # minimum :: Ord a => Proxy a -> a # sum :: Num a => Proxy a -> a # product :: Num a => Proxy a -> a #
Foldable (Map k)
Instance details Defined in Data.Map.Internal Methods fold :: Monoid m => Map k m -> m # foldMap :: Monoid m => (a -> m) -> Map k a -> m # foldr :: (a -> b -> b) -> b -> Map k a -> b # foldr' :: (a -> b -> b) -> b -> Map k a -> b # foldl :: (b -> a -> b) -> b -> Map k a -> b # foldl' :: (b -> a -> b) -> b -> Map k a -> b # foldr1 :: (a -> a -> a) -> Map k a -> a # foldl1 :: (a -> a -> a) -> Map k a -> a # toList :: Map k a -> [a] # null :: Map k a -> Bool # length :: Map k a -> Int # elem :: Eq a => a -> Map k a -> Bool # maximum :: Ord a => Map k a -> a # minimum :: Ord a => Map k a -> a # sum :: Num a => Map k a -> a # product :: Num a => Map k a -> a #
Foldable f => Foldable (MaybeT f)
Instance details Defined in Control.Monad.Trans.Maybe Methods fold :: Monoid m => MaybeT f m -> m # foldMap :: Monoid m => (a -> m) -> MaybeT f a -> m # foldr :: (a -> b -> b) -> b -> MaybeT f a -> b # foldr' :: (a -> b -> b) -> b -> MaybeT f a -> b # foldl :: (b -> a -> b) -> b -> MaybeT f a -> b # foldl' :: (b -> a -> b) -> b -> MaybeT f a -> b # foldr1 :: (a -> a -> a) -> MaybeT f a -> a # foldl1 :: (a -> a -> a) -> MaybeT f a -> a # toList :: MaybeT f a -> [a] # null :: MaybeT f a -> Bool # length :: MaybeT f a -> Int # elem :: Eq a => a -> MaybeT f a -> Bool # maximum :: Ord a => MaybeT f a -> a # minimum :: Ord a => MaybeT f a -> a # sum :: Num a => MaybeT f a -> a # product :: Num a => MaybeT f a -> a #
Foldable (HashMap k)
Instance details Defined in Data.HashMap.Base Methods fold :: Monoid m => HashMap k m -> m # foldMap :: Monoid m => (a -> m) -> HashMap k a -> m # foldr :: (a -> b -> b) -> b -> HashMap k a -> b # foldr' :: (a -> b -> b) -> b -> HashMap k a -> b # foldl :: (b -> a -> b) -> b -> HashMap k a -> b # foldl' :: (b -> a -> b) -> b -> HashMap k a -> b # foldr1 :: (a -> a -> a) -> HashMap k a -> a # foldl1 :: (a -> a -> a) -> HashMap k a -> a # toList :: HashMap k a -> [a] # null :: HashMap k a -> Bool # length :: HashMap k a -> Int # elem :: Eq a => a -> HashMap k a -> Bool # maximum :: Ord a => HashMap k a -> a # minimum :: Ord a => HashMap k a -> a # sum :: Num a => HashMap k a -> a # product :: Num a => HashMap k a -> a #
Foldable f => Foldable (Rec1 f)	Since: base-4.9.0.0
Instance details Defined in Data.Foldable Methods fold :: Monoid m => Rec1 f m -> m # foldMap :: Monoid m => (a -> m) -> Rec1 f a -> m # foldr :: (a -> b -> b) -> b -> Rec1 f a -> b # foldr' :: (a -> b -> b) -> b -> Rec1 f a -> b # foldl :: (b -> a -> b) -> b -> Rec1 f a -> b # foldl' :: (b -> a -> b) -> b -> Rec1 f a -> b # foldr1 :: (a -> a -> a) -> Rec1 f a -> a # foldl1 :: (a -> a -> a) -> Rec1 f a -> a # toList :: Rec1 f a -> [a] # null :: Rec1 f a -> Bool # length :: Rec1 f a -> Int # elem :: Eq a => a -> Rec1 f a -> Bool # maximum :: Ord a => Rec1 f a -> a # minimum :: Ord a => Rec1 f a -> a # sum :: Num a => Rec1 f a -> a # product :: Num a => Rec1 f a -> a #
Foldable (URec Char :: Type -> Type)	Since: base-4.9.0.0
Instance details Defined in Data.Foldable Methods fold :: Monoid m => URec Char m -> m # foldMap :: Monoid m => (a -> m) -> URec Char a -> m # foldr :: (a -> b -> b) -> b -> URec Char a -> b # foldr' :: (a -> b -> b) -> b -> URec Char a -> b # foldl :: (b -> a -> b) -> b -> URec Char a -> b # foldl' :: (b -> a -> b) -> b -> URec Char a -> b # foldr1 :: (a -> a -> a) -> URec Char a -> a # foldl1 :: (a -> a -> a) -> URec Char a -> a # toList :: URec Char a -> [a] # null :: URec Char a -> Bool # length :: URec Char a -> Int # elem :: Eq a => a -> URec Char a -> Bool # maximum :: Ord a => URec Char a -> a # minimum :: Ord a => URec Char a -> a # sum :: Num a => URec Char a -> a # product :: Num a => URec Char a -> a #
Foldable (URec Double :: Type -> Type)	Since: base-4.9.0.0
Instance details Defined in Data.Foldable Methods fold :: Monoid m => URec Double m -> m # foldMap :: Monoid m => (a -> m) -> URec Double a -> m # foldr :: (a -> b -> b) -> b -> URec Double a -> b # foldr' :: (a -> b -> b) -> b -> URec Double a -> b # foldl :: (b -> a -> b) -> b -> URec Double a -> b # foldl' :: (b -> a -> b) -> b -> URec Double a -> b # foldr1 :: (a -> a -> a) -> URec Double a -> a # foldl1 :: (a -> a -> a) -> URec Double a -> a # toList :: URec Double a -> [a] # null :: URec Double a -> Bool # length :: URec Double a -> Int # elem :: Eq a => a -> URec Double a -> Bool # maximum :: Ord a => URec Double a -> a # minimum :: Ord a => URec Double a -> a # sum :: Num a => URec Double a -> a # product :: Num a => URec Double a -> a #
Foldable (URec Float :: Type -> Type)	Since: base-4.9.0.0
Instance details Defined in Data.Foldable Methods fold :: Monoid m => URec Float m -> m # foldMap :: Monoid m => (a -> m) -> URec Float a -> m # foldr :: (a -> b -> b) -> b -> URec Float a -> b # foldr' :: (a -> b -> b) -> b -> URec Float a -> b # foldl :: (b -> a -> b) -> b -> URec Float a -> b # foldl' :: (b -> a -> b) -> b -> URec Float a -> b # foldr1 :: (a -> a -> a) -> URec Float a -> a # foldl1 :: (a -> a -> a) -> URec Float a -> a # toList :: URec Float a -> [a] # null :: URec Float a -> Bool # length :: URec Float a -> Int # elem :: Eq a => a -> URec Float a -> Bool # maximum :: Ord a => URec Float a -> a # minimum :: Ord a => URec Float a -> a # sum :: Num a => URec Float a -> a # product :: Num a => URec Float a -> a #
Foldable (URec Int :: Type -> Type)	Since: base-4.9.0.0
Instance details Defined in Data.Foldable Methods fold :: Monoid m => URec Int m -> m # foldMap :: Monoid m => (a -> m) -> URec Int a -> m # foldr :: (a -> b -> b) -> b -> URec Int a -> b # foldr' :: (a -> b -> b) -> b -> URec Int a -> b # foldl :: (b -> a -> b) -> b -> URec Int a -> b # foldl' :: (b -> a -> b) -> b -> URec Int a -> b # foldr1 :: (a -> a -> a) -> URec Int a -> a # foldl1 :: (a -> a -> a) -> URec Int a -> a # toList :: URec Int a -> [a] # null :: URec Int a -> Bool # length :: URec Int a -> Int # elem :: Eq a => a -> URec Int a -> Bool # maximum :: Ord a => URec Int a -> a # minimum :: Ord a => URec Int a -> a # sum :: Num a => URec Int a -> a # product :: Num a => URec Int a -> a #
Foldable (URec Word :: Type -> Type)	Since: base-4.9.0.0
Instance details Defined in Data.Foldable Methods fold :: Monoid m => URec Word m -> m # foldMap :: Monoid m => (a -> m) -> URec Word a -> m # foldr :: (a -> b -> b) -> b -> URec Word a -> b # foldr' :: (a -> b -> b) -> b -> URec Word a -> b # foldl :: (b -> a -> b) -> b -> URec Word a -> b # foldl' :: (b -> a -> b) -> b -> URec Word a -> b # foldr1 :: (a -> a -> a) -> URec Word a -> a # foldl1 :: (a -> a -> a) -> URec Word a -> a # toList :: URec Word a -> [a] # null :: URec Word a -> Bool # length :: URec Word a -> Int # elem :: Eq a => a -> URec Word a -> Bool # maximum :: Ord a => URec Word a -> a # minimum :: Ord a => URec Word a -> a # sum :: Num a => URec Word a -> a # product :: Num a => URec Word a -> a #
Foldable (URec (Ptr ()) :: Type -> Type)	Since: base-4.9.0.0
Instance details Defined in Data.Foldable Methods fold :: Monoid m => URec (Ptr ()) m -> m # foldMap :: Monoid m => (a -> m) -> URec (Ptr ()) a -> m # foldr :: (a -> b -> b) -> b -> URec (Ptr ()) a -> b # foldr' :: (a -> b -> b) -> b -> URec (Ptr ()) a -> b # foldl :: (b -> a -> b) -> b -> URec (Ptr ()) a -> b # foldl' :: (b -> a -> b) -> b -> URec (Ptr ()) a -> b # foldr1 :: (a -> a -> a) -> URec (Ptr ()) a -> a # foldl1 :: (a -> a -> a) -> URec (Ptr ()) a -> a # toList :: URec (Ptr ()) a -> [a] # null :: URec (Ptr ()) a -> Bool # length :: URec (Ptr ()) a -> Int # elem :: Eq a => a -> URec (Ptr ()) a -> Bool # maximum :: Ord a => URec (Ptr ()) a -> a # minimum :: Ord a => URec (Ptr ()) a -> a # sum :: Num a => URec (Ptr ()) a -> a # product :: Num a => URec (Ptr ()) a -> a #
Foldable (Const m :: Type -> Type)	Since: base-4.7.0.0
Instance details Defined in Data.Functor.Const Methods fold :: Monoid m0 => Const m m0 -> m0 # foldMap :: Monoid m0 => (a -> m0) -> Const m a -> m0 # foldr :: (a -> b -> b) -> b -> Const m a -> b # foldr' :: (a -> b -> b) -> b -> Const m a -> b # foldl :: (b -> a -> b) -> b -> Const m a -> b # foldl' :: (b -> a -> b) -> b -> Const m a -> b # foldr1 :: (a -> a -> a) -> Const m a -> a # foldl1 :: (a -> a -> a) -> Const m a -> a # toList :: Const m a -> [a] # null :: Const m a -> Bool # length :: Const m a -> Int # elem :: Eq a => a -> Const m a -> Bool # maximum :: Ord a => Const m a -> a # minimum :: Ord a => Const m a -> a # sum :: Num a => Const m a -> a # product :: Num a => Const m a -> a #
Foldable f => Foldable (Ap f)	Since: base-4.12.0.0
Instance details Defined in Data.Foldable Methods fold :: Monoid m => Ap f m -> m # foldMap :: Monoid m => (a -> m) -> Ap f a -> m # foldr :: (a -> b -> b) -> b -> Ap f a -> b # foldr' :: (a -> b -> b) -> b -> Ap f a -> b # foldl :: (b -> a -> b) -> b -> Ap f a -> b # foldl' :: (b -> a -> b) -> b -> Ap f a -> b # foldr1 :: (a -> a -> a) -> Ap f a -> a # foldl1 :: (a -> a -> a) -> Ap f a -> a # toList :: Ap f a -> [a] # null :: Ap f a -> Bool # length :: Ap f a -> Int # elem :: Eq a => a -> Ap f a -> Bool # maximum :: Ord a => Ap f a -> a # minimum :: Ord a => Ap f a -> a # sum :: Num a => Ap f a -> a # product :: Num a => Ap f a -> a #
Foldable f => Foldable (Alt f)	Since: base-4.12.0.0
Instance details Defined in Data.Foldable Methods fold :: Monoid m => Alt f m -> m # foldMap :: Monoid m => (a -> m) -> Alt f a -> m # foldr :: (a -> b -> b) -> b -> Alt f a -> b # foldr' :: (a -> b -> b) -> b -> Alt f a -> b # foldl :: (b -> a -> b) -> b -> Alt f a -> b # foldl' :: (b -> a -> b) -> b -> Alt f a -> b # foldr1 :: (a -> a -> a) -> Alt f a -> a # foldl1 :: (a -> a -> a) -> Alt f a -> a # toList :: Alt f a -> [a] # null :: Alt f a -> Bool # length :: Alt f a -> Int # elem :: Eq a => a -> Alt f a -> Bool # maximum :: Ord a => Alt f a -> a # minimum :: Ord a => Alt f a -> a # sum :: Num a => Alt f a -> a # product :: Num a => Alt f a -> a #
Foldable f => Foldable (ExceptT e f)
Instance details Defined in Control.Monad.Trans.Except Methods fold :: Monoid m => ExceptT e f m -> m # foldMap :: Monoid m => (a -> m) -> ExceptT e f a -> m # foldr :: (a -> b -> b) -> b -> ExceptT e f a -> b # foldr' :: (a -> b -> b) -> b -> ExceptT e f a -> b # foldl :: (b -> a -> b) -> b -> ExceptT e f a -> b # foldl' :: (b -> a -> b) -> b -> ExceptT e f a -> b # foldr1 :: (a -> a -> a) -> ExceptT e f a -> a # foldl1 :: (a -> a -> a) -> ExceptT e f a -> a # toList :: ExceptT e f a -> [a] # null :: ExceptT e f a -> Bool # length :: ExceptT e f a -> Int # elem :: Eq a => a -> ExceptT e f a -> Bool # maximum :: Ord a => ExceptT e f a -> a # minimum :: Ord a => ExceptT e f a -> a # sum :: Num a => ExceptT e f a -> a # product :: Num a => ExceptT e f a -> a #
Foldable f => Foldable (IdentityT f)
Instance details Defined in Control.Monad.Trans.Identity Methods fold :: Monoid m => IdentityT f m -> m # foldMap :: Monoid m => (a -> m) -> IdentityT f a -> m # foldr :: (a -> b -> b) -> b -> IdentityT f a -> b # foldr' :: (a -> b -> b) -> b -> IdentityT f a -> b # foldl :: (b -> a -> b) -> b -> IdentityT f a -> b # foldl' :: (b -> a -> b) -> b -> IdentityT f a -> b # foldr1 :: (a -> a -> a) -> IdentityT f a -> a # foldl1 :: (a -> a -> a) -> IdentityT f a -> a # toList :: IdentityT f a -> [a] # null :: IdentityT f a -> Bool # length :: IdentityT f a -> Int # elem :: Eq a => a -> IdentityT f a -> Bool # maximum :: Ord a => IdentityT f a -> a # minimum :: Ord a => IdentityT f a -> a # sum :: Num a => IdentityT f a -> a # product :: Num a => IdentityT f a -> a #
Foldable f => Foldable (ErrorT e f)
Instance details Defined in Control.Monad.Trans.Error Methods fold :: Monoid m => ErrorT e f m -> m # foldMap :: Monoid m => (a -> m) -> ErrorT e f a -> m # foldr :: (a -> b -> b) -> b -> ErrorT e f a -> b # foldr' :: (a -> b -> b) -> b -> ErrorT e f a -> b # foldl :: (b -> a -> b) -> b -> ErrorT e f a -> b # foldl' :: (b -> a -> b) -> b -> ErrorT e f a -> b # foldr1 :: (a -> a -> a) -> ErrorT e f a -> a # foldl1 :: (a -> a -> a) -> ErrorT e f a -> a # toList :: ErrorT e f a -> [a] # null :: ErrorT e f a -> Bool # length :: ErrorT e f a -> Int # elem :: Eq a => a -> ErrorT e f a -> Bool # maximum :: Ord a => ErrorT e f a -> a # minimum :: Ord a => ErrorT e f a -> a # sum :: Num a => ErrorT e f a -> a # product :: Num a => ErrorT e f a -> a #
Foldable (K1 i c :: Type -> Type)	Since: base-4.9.0.0
Instance details Defined in Data.Foldable Methods fold :: Monoid m => K1 i c m -> m # foldMap :: Monoid m => (a -> m) -> K1 i c a -> m # foldr :: (a -> b -> b) -> b -> K1 i c a -> b # foldr' :: (a -> b -> b) -> b -> K1 i c a -> b # foldl :: (b -> a -> b) -> b -> K1 i c a -> b # foldl' :: (b -> a -> b) -> b -> K1 i c a -> b # foldr1 :: (a -> a -> a) -> K1 i c a -> a # foldl1 :: (a -> a -> a) -> K1 i c a -> a # toList :: K1 i c a -> [a] # null :: K1 i c a -> Bool # length :: K1 i c a -> Int # elem :: Eq a => a -> K1 i c a -> Bool # maximum :: Ord a => K1 i c a -> a # minimum :: Ord a => K1 i c a -> a # sum :: Num a => K1 i c a -> a # product :: Num a => K1 i c a -> a #
(Foldable f, Foldable g) => Foldable (f :+: g)	Since: base-4.9.0.0
Instance details Defined in Data.Foldable Methods fold :: Monoid m => (f :+: g) m -> m # foldMap :: Monoid m => (a -> m) -> (f :+: g) a -> m # foldr :: (a -> b -> b) -> b -> (f :+: g) a -> b # foldr' :: (a -> b -> b) -> b -> (f :+: g) a -> b # foldl :: (b -> a -> b) -> b -> (f :+: g) a -> b # foldl' :: (b -> a -> b) -> b -> (f :+: g) a -> b # foldr1 :: (a -> a -> a) -> (f :+: g) a -> a # foldl1 :: (a -> a -> a) -> (f :+: g) a -> a # toList :: (f :+: g) a -> [a] # null :: (f :+: g) a -> Bool # length :: (f :+: g) a -> Int # elem :: Eq a => a -> (f :+: g) a -> Bool # maximum :: Ord a => (f :+: g) a -> a # minimum :: Ord a => (f :+: g) a -> a # sum :: Num a => (f :+: g) a -> a # product :: Num a => (f :+: g) a -> a #
(Foldable f, Foldable g) => Foldable (f :*: g)	Since: base-4.9.0.0
Instance details Defined in Data.Foldable Methods fold :: Monoid m => (f :: g) m -> m # foldMap :: Monoid m => (a -> m) -> (f :: g) a -> m # foldr :: (a -> b -> b) -> b -> (f :: g) a -> b # foldr' :: (a -> b -> b) -> b -> (f :: g) a -> b # foldl :: (b -> a -> b) -> b -> (f :: g) a -> b # foldl' :: (b -> a -> b) -> b -> (f :: g) a -> b # foldr1 :: (a -> a -> a) -> (f :: g) a -> a # foldl1 :: (a -> a -> a) -> (f :: g) a -> a # toList :: (f :: g) a -> [a] # null :: (f :: g) a -> Bool # length :: (f :: g) a -> Int # elem :: Eq a => a -> (f :: g) a -> Bool # maximum :: Ord a => (f :: g) a -> a # minimum :: Ord a => (f :: g) a -> a # sum :: Num a => (f :: g) a -> a # product :: Num a => (f :: g) a -> a #
Foldable f => Foldable (M1 i c f)	Since: base-4.9.0.0
Instance details Defined in Data.Foldable Methods fold :: Monoid m => M1 i c f m -> m # foldMap :: Monoid m => (a -> m) -> M1 i c f a -> m # foldr :: (a -> b -> b) -> b -> M1 i c f a -> b # foldr' :: (a -> b -> b) -> b -> M1 i c f a -> b # foldl :: (b -> a -> b) -> b -> M1 i c f a -> b # foldl' :: (b -> a -> b) -> b -> M1 i c f a -> b # foldr1 :: (a -> a -> a) -> M1 i c f a -> a # foldl1 :: (a -> a -> a) -> M1 i c f a -> a # toList :: M1 i c f a -> [a] # null :: M1 i c f a -> Bool # length :: M1 i c f a -> Int # elem :: Eq a => a -> M1 i c f a -> Bool # maximum :: Ord a => M1 i c f a -> a # minimum :: Ord a => M1 i c f a -> a # sum :: Num a => M1 i c f a -> a # product :: Num a => M1 i c f a -> a #
(Foldable f, Foldable g) => Foldable (f :.: g)	Since: base-4.9.0.0
Instance details Defined in Data.Foldable Methods fold :: Monoid m => (f :.: g) m -> m # foldMap :: Monoid m => (a -> m) -> (f :.: g) a -> m # foldr :: (a -> b -> b) -> b -> (f :.: g) a -> b # foldr' :: (a -> b -> b) -> b -> (f :.: g) a -> b # foldl :: (b -> a -> b) -> b -> (f :.: g) a -> b # foldl' :: (b -> a -> b) -> b -> (f :.: g) a -> b # foldr1 :: (a -> a -> a) -> (f :.: g) a -> a # foldl1 :: (a -> a -> a) -> (f :.: g) a -> a # toList :: (f :.: g) a -> [a] # null :: (f :.: g) a -> Bool # length :: (f :.: g) a -> Int # elem :: Eq a => a -> (f :.: g) a -> Bool # maximum :: Ord a => (f :.: g) a -> a # minimum :: Ord a => (f :.: g) a -> a # sum :: Num a => (f :.: g) a -> a # product :: Num a => (f :.: g) a -> a #
(Foldable f, Foldable g) => Foldable (Compose f g)	Since: base-4.9.0.0
Instance details Defined in Data.Functor.Compose Methods fold :: Monoid m => Compose f g m -> m # foldMap :: Monoid m => (a -> m) -> Compose f g a -> m # foldr :: (a -> b -> b) -> b -> Compose f g a -> b # foldr' :: (a -> b -> b) -> b -> Compose f g a -> b # foldl :: (b -> a -> b) -> b -> Compose f g a -> b # foldl' :: (b -> a -> b) -> b -> Compose f g a -> b # foldr1 :: (a -> a -> a) -> Compose f g a -> a # foldl1 :: (a -> a -> a) -> Compose f g a -> a # toList :: Compose f g a -> [a] # null :: Compose f g a -> Bool # length :: Compose f g a -> Int # elem :: Eq a => a -> Compose f g a -> Bool # maximum :: Ord a => Compose f g a -> a # minimum :: Ord a => Compose f g a -> a # sum :: Num a => Compose f g a -> a # product :: Num a => Compose f g a -> a #

class (Functor t, Foldable t) => Traversable (t :: Type -> Type) where #

Functors representing data structures that can be traversed from left to right.

A definition of traverse must satisfy the following laws:

naturality: t . traverse f = traverse (t . f) for every applicative transformation t
identity: traverse Identity = Identity
composition: traverse (Compose . fmap g . f) = Compose . fmap (traverse g) . traverse f

A definition of sequenceA must satisfy the following laws:

naturality: t . sequenceA = sequenceA . fmap t for every applicative transformation t
identity: sequenceA . fmap Identity = Identity
composition: sequenceA . fmap Compose = Compose . fmap sequenceA . sequenceA

where an applicative transformation is a function

t :: (Applicative f, Applicative g) => f a -> g a

preserving the Applicative operations, i.e.

```
t (pure x) = pure x
```
```
t (x <*> y) = t x <*> t y
```

and the identity functor Identity and composition of functors Compose are defined as

  newtype Identity a = Identity a

  instance Functor Identity where
    fmap f (Identity x) = Identity (f x)

  instance Applicative Identity where
    pure x = Identity x
    Identity f <*> Identity x = Identity (f x)

  newtype Compose f g a = Compose (f (g a))

  instance (Functor f, Functor g) => Functor (Compose f g) where
    fmap f (Compose x) = Compose (fmap (fmap f) x)

  instance (Applicative f, Applicative g) => Applicative (Compose f g) where
    pure x = Compose (pure (pure x))
    Compose f <*> Compose x = Compose ((<*>) <$> f <*> x)

(The naturality law is implied by parametricity.)

Instances are similar to Functor, e.g. given a data type

data Tree a = Empty | Leaf a | Node (Tree a) a (Tree a)

a suitable instance would be

instance Traversable Tree where
   traverse f Empty = pure Empty
   traverse f (Leaf x) = Leaf <$> f x
   traverse f (Node l k r) = Node <$> traverse f l <*> f k <*> traverse f r

This is suitable even for abstract types, as the laws for <*> imply a form of associativity.

The superclass instances should satisfy the following:

In the Functor instance, fmap should be equivalent to traversal with the identity applicative functor (fmapDefault).
In the Foldable instance, foldMap should be equivalent to traversal with a constant applicative functor (foldMapDefault).

Minimal complete definition

traverse | sequenceA

Methods

traverse :: Applicative f => (a -> f b) -> t a -> f (t b) #

Map each element of a structure to an action, evaluate these actions from left to right, and collect the results. For a version that ignores the results see traverse_.

sequenceA :: Applicative f => t (f a) -> f (t a) #

Evaluate each action in the structure from left to right, and collect the results. For a version that ignores the results see sequenceA_.

mapM :: Monad m => (a -> m b) -> t a -> m (t b) #

Map each element of a structure to a monadic action, evaluate these actions from left to right, and collect the results. For a version that ignores the results see mapM_.

sequence :: Monad m => t (m a) -> m (t a) #

Evaluate each monadic action in the structure from left to right, and collect the results. For a version that ignores the results see sequence_.

Instances

Traversable []	Since: base-2.1
Instance details Defined in Data.Traversable Methods traverse :: Applicative f => (a -> f b) -> [a] -> f [b] # sequenceA :: Applicative f => [f a] -> f [a] # mapM :: Monad m => (a -> m b) -> [a] -> m [b] # sequence :: Monad m => [m a] -> m [a] #
Traversable Maybe	Since: base-2.1
Instance details Defined in Data.Traversable Methods traverse :: Applicative f => (a -> f b) -> Maybe a -> f (Maybe b) # sequenceA :: Applicative f => Maybe (f a) -> f (Maybe a) # mapM :: Monad m => (a -> m b) -> Maybe a -> m (Maybe b) # sequence :: Monad m => Maybe (m a) -> m (Maybe a) #
Traversable Par1	Since: base-4.9.0.0
Instance details Defined in Data.Traversable Methods traverse :: Applicative f => (a -> f b) -> Par1 a -> f (Par1 b) # sequenceA :: Applicative f => Par1 (f a) -> f (Par1 a) # mapM :: Monad m => (a -> m b) -> Par1 a -> m (Par1 b) # sequence :: Monad m => Par1 (m a) -> m (Par1 a) #
Traversable Min	Since: base-4.9.0.0
Instance details Defined in Data.Semigroup Methods traverse :: Applicative f => (a -> f b) -> Min a -> f (Min b) # sequenceA :: Applicative f => Min (f a) -> f (Min a) # mapM :: Monad m => (a -> m b) -> Min a -> m (Min b) # sequence :: Monad m => Min (m a) -> m (Min a) #
Traversable Max	Since: base-4.9.0.0
Instance details Defined in Data.Semigroup Methods traverse :: Applicative f => (a -> f b) -> Max a -> f (Max b) # sequenceA :: Applicative f => Max (f a) -> f (Max a) # mapM :: Monad m => (a -> m b) -> Max a -> m (Max b) # sequence :: Monad m => Max (m a) -> m (Max a) #
Traversable First	Since: base-4.9.0.0
Instance details Defined in Data.Semigroup Methods traverse :: Applicative f => (a -> f b) -> First a -> f (First b) # sequenceA :: Applicative f => First (f a) -> f (First a) # mapM :: Monad m => (a -> m b) -> First a -> m (First b) # sequence :: Monad m => First (m a) -> m (First a) #
Traversable Last	Since: base-4.9.0.0
Instance details Defined in Data.Semigroup Methods traverse :: Applicative f => (a -> f b) -> Last a -> f (Last b) # sequenceA :: Applicative f => Last (f a) -> f (Last a) # mapM :: Monad m => (a -> m b) -> Last a -> m (Last b) # sequence :: Monad m => Last (m a) -> m (Last a) #
Traversable Option	Since: base-4.9.0.0
Instance details Defined in Data.Semigroup Methods traverse :: Applicative f => (a -> f b) -> Option a -> f (Option b) # sequenceA :: Applicative f => Option (f a) -> f (Option a) # mapM :: Monad m => (a -> m b) -> Option a -> m (Option b) # sequence :: Monad m => Option (m a) -> m (Option a) #
Traversable ZipList	Since: base-4.9.0.0
Instance details Defined in Data.Traversable Methods traverse :: Applicative f => (a -> f b) -> ZipList a -> f (ZipList b) # sequenceA :: Applicative f => ZipList (f a) -> f (ZipList a) # mapM :: Monad m => (a -> m b) -> ZipList a -> m (ZipList b) # sequence :: Monad m => ZipList (m a) -> m (ZipList a) #
Traversable Identity	Since: base-4.9.0.0
Instance details Defined in Data.Traversable Methods traverse :: Applicative f => (a -> f b) -> Identity a -> f (Identity b) # sequenceA :: Applicative f => Identity (f a) -> f (Identity a) # mapM :: Monad m => (a -> m b) -> Identity a -> m (Identity b) # sequence :: Monad m => Identity (m a) -> m (Identity a) #
Traversable First	Since: base-4.8.0.0
Instance details Defined in Data.Traversable Methods traverse :: Applicative f => (a -> f b) -> First a -> f (First b) # sequenceA :: Applicative f => First (f a) -> f (First a) # mapM :: Monad m => (a -> m b) -> First a -> m (First b) # sequence :: Monad m => First (m a) -> m (First a) #
Traversable Last	Since: base-4.8.0.0
Instance details Defined in Data.Traversable Methods traverse :: Applicative f => (a -> f b) -> Last a -> f (Last b) # sequenceA :: Applicative f => Last (f a) -> f (Last a) # mapM :: Monad m => (a -> m b) -> Last a -> m (Last b) # sequence :: Monad m => Last (m a) -> m (Last a) #
Traversable Dual	Since: base-4.8.0.0
Instance details Defined in Data.Traversable Methods traverse :: Applicative f => (a -> f b) -> Dual a -> f (Dual b) # sequenceA :: Applicative f => Dual (f a) -> f (Dual a) # mapM :: Monad m => (a -> m b) -> Dual a -> m (Dual b) # sequence :: Monad m => Dual (m a) -> m (Dual a) #
Traversable Sum	Since: base-4.8.0.0
Instance details Defined in Data.Traversable Methods traverse :: Applicative f => (a -> f b) -> Sum a -> f (Sum b) # sequenceA :: Applicative f => Sum (f a) -> f (Sum a) # mapM :: Monad m => (a -> m b) -> Sum a -> m (Sum b) # sequence :: Monad m => Sum (m a) -> m (Sum a) #
Traversable Product	Since: base-4.8.0.0
Instance details Defined in Data.Traversable Methods traverse :: Applicative f => (a -> f b) -> Product a -> f (Product b) # sequenceA :: Applicative f => Product (f a) -> f (Product a) # mapM :: Monad m => (a -> m b) -> Product a -> m (Product b) # sequence :: Monad m => Product (m a) -> m (Product a) #
Traversable Down	Since: base-4.12.0.0
Instance details Defined in Data.Traversable Methods traverse :: Applicative f => (a -> f b) -> Down a -> f (Down b) # sequenceA :: Applicative f => Down (f a) -> f (Down a) # mapM :: Monad m => (a -> m b) -> Down a -> m (Down b) # sequence :: Monad m => Down (m a) -> m (Down a) #
Traversable NonEmpty	Since: base-4.9.0.0
Instance details Defined in Data.Traversable Methods traverse :: Applicative f => (a -> f b) -> NonEmpty a -> f (NonEmpty b) # sequenceA :: Applicative f => NonEmpty (f a) -> f (NonEmpty a) # mapM :: Monad m => (a -> m b) -> NonEmpty a -> m (NonEmpty b) # sequence :: Monad m => NonEmpty (m a) -> m (NonEmpty a) #
Traversable IntMap
Instance details Defined in Data.IntMap.Internal Methods traverse :: Applicative f => (a -> f b) -> IntMap a -> f (IntMap b) # sequenceA :: Applicative f => IntMap (f a) -> f (IntMap a) # mapM :: Monad m => (a -> m b) -> IntMap a -> m (IntMap b) # sequence :: Monad m => IntMap (m a) -> m (IntMap a) #
Traversable Seq
Instance details Defined in Data.Sequence.Internal Methods traverse :: Applicative f => (a -> f b) -> Seq a -> f (Seq b) # sequenceA :: Applicative f => Seq (f a) -> f (Seq a) # mapM :: Monad m => (a -> m b) -> Seq a -> m (Seq b) # sequence :: Monad m => Seq (m a) -> m (Seq a) #
Traversable FingerTree
Instance details Defined in Data.Sequence.Internal Methods traverse :: Applicative f => (a -> f b) -> FingerTree a -> f (FingerTree b) # sequenceA :: Applicative f => FingerTree (f a) -> f (FingerTree a) # mapM :: Monad m => (a -> m b) -> FingerTree a -> m (FingerTree b) # sequence :: Monad m => FingerTree (m a) -> m (FingerTree a) #
Traversable Digit
Instance details Defined in Data.Sequence.Internal Methods traverse :: Applicative f => (a -> f b) -> Digit a -> f (Digit b) # sequenceA :: Applicative f => Digit (f a) -> f (Digit a) # mapM :: Monad m => (a -> m b) -> Digit a -> m (Digit b) # sequence :: Monad m => Digit (m a) -> m (Digit a) #
Traversable Node
Instance details Defined in Data.Sequence.Internal Methods traverse :: Applicative f => (a -> f b) -> Node a -> f (Node b) # sequenceA :: Applicative f => Node (f a) -> f (Node a) # mapM :: Monad m => (a -> m b) -> Node a -> m (Node b) # sequence :: Monad m => Node (m a) -> m (Node a) #
Traversable Elem
Instance details Defined in Data.Sequence.Internal Methods traverse :: Applicative f => (a -> f b) -> Elem a -> f (Elem b) # sequenceA :: Applicative f => Elem (f a) -> f (Elem a) # mapM :: Monad m => (a -> m b) -> Elem a -> m (Elem b) # sequence :: Monad m => Elem (m a) -> m (Elem a) #
Traversable ViewL
Instance details Defined in Data.Sequence.Internal Methods traverse :: Applicative f => (a -> f b) -> ViewL a -> f (ViewL b) # sequenceA :: Applicative f => ViewL (f a) -> f (ViewL a) # mapM :: Monad m => (a -> m b) -> ViewL a -> m (ViewL b) # sequence :: Monad m => ViewL (m a) -> m (ViewL a) #
Traversable ViewR
Instance details Defined in Data.Sequence.Internal Methods traverse :: Applicative f => (a -> f b) -> ViewR a -> f (ViewR b) # sequenceA :: Applicative f => ViewR (f a) -> f (ViewR a) # mapM :: Monad m => (a -> m b) -> ViewR a -> m (ViewR b) # sequence :: Monad m => ViewR (m a) -> m (ViewR a) #
Traversable Vector
Instance details Defined in Data.Vector Methods traverse :: Applicative f => (a -> f b) -> Vector a -> f (Vector b) # sequenceA :: Applicative f => Vector (f a) -> f (Vector a) # mapM :: Monad m => (a -> m b) -> Vector a -> m (Vector b) # sequence :: Monad m => Vector (m a) -> m (Vector a) #
Traversable (Either a)	Since: base-4.7.0.0
Instance details Defined in Data.Traversable Methods traverse :: Applicative f => (a0 -> f b) -> Either a a0 -> f (Either a b) # sequenceA :: Applicative f => Either a (f a0) -> f (Either a a0) # mapM :: Monad m => (a0 -> m b) -> Either a a0 -> m (Either a b) # sequence :: Monad m => Either a (m a0) -> m (Either a a0) #
Traversable (V1 :: Type -> Type)	Since: base-4.9.0.0
Instance details Defined in Data.Traversable Methods traverse :: Applicative f => (a -> f b) -> V1 a -> f (V1 b) # sequenceA :: Applicative f => V1 (f a) -> f (V1 a) # mapM :: Monad m => (a -> m b) -> V1 a -> m (V1 b) # sequence :: Monad m => V1 (m a) -> m (V1 a) #
Traversable (U1 :: Type -> Type)	Since: base-4.9.0.0
Instance details Defined in Data.Traversable Methods traverse :: Applicative f => (a -> f b) -> U1 a -> f (U1 b) # sequenceA :: Applicative f => U1 (f a) -> f (U1 a) # mapM :: Monad m => (a -> m b) -> U1 a -> m (U1 b) # sequence :: Monad m => U1 (m a) -> m (U1 a) #
Traversable ((,) a)	Since: base-4.7.0.0
Instance details Defined in Data.Traversable Methods traverse :: Applicative f => (a0 -> f b) -> (a, a0) -> f (a, b) # sequenceA :: Applicative f => (a, f a0) -> f (a, a0) # mapM :: Monad m => (a0 -> m b) -> (a, a0) -> m (a, b) # sequence :: Monad m => (a, m a0) -> m (a, a0) #
Ix i => Traversable (Array i)	Since: base-2.1
Instance details Defined in Data.Traversable Methods traverse :: Applicative f => (a -> f b) -> Array i a -> f (Array i b) # sequenceA :: Applicative f => Array i (f a) -> f (Array i a) # mapM :: Monad m => (a -> m b) -> Array i a -> m (Array i b) # sequence :: Monad m => Array i (m a) -> m (Array i a) #
Traversable (Arg a)	Since: base-4.9.0.0
Instance details Defined in Data.Semigroup Methods traverse :: Applicative f => (a0 -> f b) -> Arg a a0 -> f (Arg a b) # sequenceA :: Applicative f => Arg a (f a0) -> f (Arg a a0) # mapM :: Monad m => (a0 -> m b) -> Arg a a0 -> m (Arg a b) # sequence :: Monad m => Arg a (m a0) -> m (Arg a a0) #
Traversable (Proxy :: Type -> Type)	Since: base-4.7.0.0
Instance details Defined in Data.Traversable Methods traverse :: Applicative f => (a -> f b) -> Proxy a -> f (Proxy b) # sequenceA :: Applicative f => Proxy (f a) -> f (Proxy a) # mapM :: Monad m => (a -> m b) -> Proxy a -> m (Proxy b) # sequence :: Monad m => Proxy (m a) -> m (Proxy a) #
Traversable (Map k)
Instance details Defined in Data.Map.Internal Methods traverse :: Applicative f => (a -> f b) -> Map k a -> f (Map k b) # sequenceA :: Applicative f => Map k (f a) -> f (Map k a) # mapM :: Monad m => (a -> m b) -> Map k a -> m (Map k b) # sequence :: Monad m => Map k (m a) -> m (Map k a) #
Traversable f => Traversable (MaybeT f)
Instance details Defined in Control.Monad.Trans.Maybe Methods traverse :: Applicative f0 => (a -> f0 b) -> MaybeT f a -> f0 (MaybeT f b) # sequenceA :: Applicative f0 => MaybeT f (f0 a) -> f0 (MaybeT f a) # mapM :: Monad m => (a -> m b) -> MaybeT f a -> m (MaybeT f b) # sequence :: Monad m => MaybeT f (m a) -> m (MaybeT f a) #
Traversable (HashMap k)
Instance details Defined in Data.HashMap.Base Methods traverse :: Applicative f => (a -> f b) -> HashMap k a -> f (HashMap k b) # sequenceA :: Applicative f => HashMap k (f a) -> f (HashMap k a) # mapM :: Monad m => (a -> m b) -> HashMap k a -> m (HashMap k b) # sequence :: Monad m => HashMap k (m a) -> m (HashMap k a) #
Traversable f => Traversable (Rec1 f)	Since: base-4.9.0.0
Instance details Defined in Data.Traversable Methods traverse :: Applicative f0 => (a -> f0 b) -> Rec1 f a -> f0 (Rec1 f b) # sequenceA :: Applicative f0 => Rec1 f (f0 a) -> f0 (Rec1 f a) # mapM :: Monad m => (a -> m b) -> Rec1 f a -> m (Rec1 f b) # sequence :: Monad m => Rec1 f (m a) -> m (Rec1 f a) #
Traversable (URec Char :: Type -> Type)	Since: base-4.9.0.0
Instance details Defined in Data.Traversable Methods traverse :: Applicative f => (a -> f b) -> URec Char a -> f (URec Char b) # sequenceA :: Applicative f => URec Char (f a) -> f (URec Char a) # mapM :: Monad m => (a -> m b) -> URec Char a -> m (URec Char b) # sequence :: Monad m => URec Char (m a) -> m (URec Char a) #
Traversable (URec Double :: Type -> Type)	Since: base-4.9.0.0
Instance details Defined in Data.Traversable Methods traverse :: Applicative f => (a -> f b) -> URec Double a -> f (URec Double b) # sequenceA :: Applicative f => URec Double (f a) -> f (URec Double a) # mapM :: Monad m => (a -> m b) -> URec Double a -> m (URec Double b) # sequence :: Monad m => URec Double (m a) -> m (URec Double a) #
Traversable (URec Float :: Type -> Type)	Since: base-4.9.0.0
Instance details Defined in Data.Traversable Methods traverse :: Applicative f => (a -> f b) -> URec Float a -> f (URec Float b) # sequenceA :: Applicative f => URec Float (f a) -> f (URec Float a) # mapM :: Monad m => (a -> m b) -> URec Float a -> m (URec Float b) # sequence :: Monad m => URec Float (m a) -> m (URec Float a) #
Traversable (URec Int :: Type -> Type)	Since: base-4.9.0.0
Instance details Defined in Data.Traversable Methods traverse :: Applicative f => (a -> f b) -> URec Int a -> f (URec Int b) # sequenceA :: Applicative f => URec Int (f a) -> f (URec Int a) # mapM :: Monad m => (a -> m b) -> URec Int a -> m (URec Int b) # sequence :: Monad m => URec Int (m a) -> m (URec Int a) #
Traversable (URec Word :: Type -> Type)	Since: base-4.9.0.0
Instance details Defined in Data.Traversable Methods traverse :: Applicative f => (a -> f b) -> URec Word a -> f (URec Word b) # sequenceA :: Applicative f => URec Word (f a) -> f (URec Word a) # mapM :: Monad m => (a -> m b) -> URec Word a -> m (URec Word b) # sequence :: Monad m => URec Word (m a) -> m (URec Word a) #
Traversable (URec (Ptr ()) :: Type -> Type)	Since: base-4.9.0.0
Instance details Defined in Data.Traversable Methods traverse :: Applicative f => (a -> f b) -> URec (Ptr ()) a -> f (URec (Ptr ()) b) # sequenceA :: Applicative f => URec (Ptr ()) (f a) -> f (URec (Ptr ()) a) # mapM :: Monad m => (a -> m b) -> URec (Ptr ()) a -> m (URec (Ptr ()) b) # sequence :: Monad m => URec (Ptr ()) (m a) -> m (URec (Ptr ()) a) #
Traversable (Const m :: Type -> Type)	Since: base-4.7.0.0
Instance details Defined in Data.Traversable Methods traverse :: Applicative f => (a -> f b) -> Const m a -> f (Const m b) # sequenceA :: Applicative f => Const m (f a) -> f (Const m a) # mapM :: Monad m0 => (a -> m0 b) -> Const m a -> m0 (Const m b) # sequence :: Monad m0 => Const m (m0 a) -> m0 (Const m a) #
Traversable f => Traversable (Ap f)	Since: base-4.12.0.0
Instance details Defined in Data.Traversable Methods traverse :: Applicative f0 => (a -> f0 b) -> Ap f a -> f0 (Ap f b) # sequenceA :: Applicative f0 => Ap f (f0 a) -> f0 (Ap f a) # mapM :: Monad m => (a -> m b) -> Ap f a -> m (Ap f b) # sequence :: Monad m => Ap f (m a) -> m (Ap f a) #
Traversable f => Traversable (Alt f)	Since: base-4.12.0.0
Instance details Defined in Data.Traversable Methods traverse :: Applicative f0 => (a -> f0 b) -> Alt f a -> f0 (Alt f b) # sequenceA :: Applicative f0 => Alt f (f0 a) -> f0 (Alt f a) # mapM :: Monad m => (a -> m b) -> Alt f a -> m (Alt f b) # sequence :: Monad m => Alt f (m a) -> m (Alt f a) #
Traversable f => Traversable (ExceptT e f)
Instance details Defined in Control.Monad.Trans.Except Methods traverse :: Applicative f0 => (a -> f0 b) -> ExceptT e f a -> f0 (ExceptT e f b) # sequenceA :: Applicative f0 => ExceptT e f (f0 a) -> f0 (ExceptT e f a) # mapM :: Monad m => (a -> m b) -> ExceptT e f a -> m (ExceptT e f b) # sequence :: Monad m => ExceptT e f (m a) -> m (ExceptT e f a) #
Traversable f => Traversable (IdentityT f)
Instance details Defined in Control.Monad.Trans.Identity Methods traverse :: Applicative f0 => (a -> f0 b) -> IdentityT f a -> f0 (IdentityT f b) # sequenceA :: Applicative f0 => IdentityT f (f0 a) -> f0 (IdentityT f a) # mapM :: Monad m => (a -> m b) -> IdentityT f a -> m (IdentityT f b) # sequence :: Monad m => IdentityT f (m a) -> m (IdentityT f a) #
Traversable f => Traversable (ErrorT e f)
Instance details Defined in Control.Monad.Trans.Error Methods traverse :: Applicative f0 => (a -> f0 b) -> ErrorT e f a -> f0 (ErrorT e f b) # sequenceA :: Applicative f0 => ErrorT e f (f0 a) -> f0 (ErrorT e f a) # mapM :: Monad m => (a -> m b) -> ErrorT e f a -> m (ErrorT e f b) # sequence :: Monad m => ErrorT e f (m a) -> m (ErrorT e f a) #
Traversable (K1 i c :: Type -> Type)	Since: base-4.9.0.0
Instance details Defined in Data.Traversable Methods traverse :: Applicative f => (a -> f b) -> K1 i c a -> f (K1 i c b) # sequenceA :: Applicative f => K1 i c (f a) -> f (K1 i c a) # mapM :: Monad m => (a -> m b) -> K1 i c a -> m (K1 i c b) # sequence :: Monad m => K1 i c (m a) -> m (K1 i c a) #
(Traversable f, Traversable g) => Traversable (f :+: g)	Since: base-4.9.0.0
Instance details Defined in Data.Traversable Methods traverse :: Applicative f0 => (a -> f0 b) -> (f :+: g) a -> f0 ((f :+: g) b) # sequenceA :: Applicative f0 => (f :+: g) (f0 a) -> f0 ((f :+: g) a) # mapM :: Monad m => (a -> m b) -> (f :+: g) a -> m ((f :+: g) b) # sequence :: Monad m => (f :+: g) (m a) -> m ((f :+: g) a) #
(Traversable f, Traversable g) => Traversable (f :*: g)	Since: base-4.9.0.0
Instance details Defined in Data.Traversable Methods traverse :: Applicative f0 => (a -> f0 b) -> (f :: g) a -> f0 ((f :: g) b) # sequenceA :: Applicative f0 => (f :: g) (f0 a) -> f0 ((f :: g) a) # mapM :: Monad m => (a -> m b) -> (f :: g) a -> m ((f :: g) b) # sequence :: Monad m => (f :: g) (m a) -> m ((f :: g) a) #
Traversable f => Traversable (M1 i c f)	Since: base-4.9.0.0
Instance details Defined in Data.Traversable Methods traverse :: Applicative f0 => (a -> f0 b) -> M1 i c f a -> f0 (M1 i c f b) # sequenceA :: Applicative f0 => M1 i c f (f0 a) -> f0 (M1 i c f a) # mapM :: Monad m => (a -> m b) -> M1 i c f a -> m (M1 i c f b) # sequence :: Monad m => M1 i c f (m a) -> m (M1 i c f a) #
(Traversable f, Traversable g) => Traversable (f :.: g)	Since: base-4.9.0.0
Instance details Defined in Data.Traversable Methods traverse :: Applicative f0 => (a -> f0 b) -> (f :.: g) a -> f0 ((f :.: g) b) # sequenceA :: Applicative f0 => (f :.: g) (f0 a) -> f0 ((f :.: g) a) # mapM :: Monad m => (a -> m b) -> (f :.: g) a -> m ((f :.: g) b) # sequence :: Monad m => (f :.: g) (m a) -> m ((f :.: g) a) #
(Traversable f, Traversable g) => Traversable (Compose f g)	Since: base-4.9.0.0
Instance details Defined in Data.Functor.Compose Methods traverse :: Applicative f0 => (a -> f0 b) -> Compose f g a -> f0 (Compose f g b) # sequenceA :: Applicative f0 => Compose f g (f0 a) -> f0 (Compose f g a) # mapM :: Monad m => (a -> m b) -> Compose f g a -> m (Compose f g b) # sequence :: Monad m => Compose f g (m a) -> m (Compose f g a) #

class Generic a #

Representable types of kind *. This class is derivable in GHC with the DeriveGeneric flag on.

A Generic instance must satisfy the following laws:

from . to ≡ id
to . from ≡ id

Minimal complete definition

from, to

Instances

Generic Bool
Instance details Defined in GHC.Generics Associated Types type Rep Bool :: Type -> Type # Methods from :: Bool -> Rep Bool x # to :: Rep Bool x -> Bool #
Generic Ordering
Instance details Defined in GHC.Generics Associated Types type Rep Ordering :: Type -> Type # Methods from :: Ordering -> Rep Ordering x # to :: Rep Ordering x -> Ordering #
Generic ()
Instance details Defined in GHC.Generics Associated Types type Rep () :: Type -> Type # Methods from :: () -> Rep () x # to :: Rep () x -> () #
Generic Void
Instance details Defined in Data.Void Associated Types type Rep Void :: Type -> Type # Methods from :: Void -> Rep Void x # to :: Rep Void x -> Void #
Generic Version
Instance details Defined in Data.Version Associated Types type Rep Version :: Type -> Type # Methods from :: Version -> Rep Version x # to :: Rep Version x -> Version #
Generic ExitCode
Instance details Defined in GHC.IO.Exception Associated Types type Rep ExitCode :: Type -> Type # Methods from :: ExitCode -> Rep ExitCode x # to :: Rep ExitCode x -> ExitCode #
Generic All
Instance details Defined in Data.Semigroup.Internal Associated Types type Rep All :: Type -> Type # Methods from :: All -> Rep All x # to :: Rep All x -> All #
Generic Any
Instance details Defined in Data.Semigroup.Internal Associated Types type Rep Any :: Type -> Type # Methods from :: Any -> Rep Any x # to :: Rep Any x -> Any #
Generic Fixity
Instance details Defined in GHC.Generics Associated Types type Rep Fixity :: Type -> Type # Methods from :: Fixity -> Rep Fixity x # to :: Rep Fixity x -> Fixity #
Generic Associativity
Instance details Defined in GHC.Generics Associated Types type Rep Associativity :: Type -> Type # Methods from :: Associativity -> Rep Associativity x # to :: Rep Associativity x -> Associativity #
Generic SourceUnpackedness
Instance details Defined in GHC.Generics Associated Types type Rep SourceUnpackedness :: Type -> Type # Methods from :: SourceUnpackedness -> Rep SourceUnpackedness x # to :: Rep SourceUnpackedness x -> SourceUnpackedness #
Generic SourceStrictness
Instance details Defined in GHC.Generics Associated Types type Rep SourceStrictness :: Type -> Type # Methods from :: SourceStrictness -> Rep SourceStrictness x # to :: Rep SourceStrictness x -> SourceStrictness #
Generic DecidedStrictness
Instance details Defined in GHC.Generics Associated Types type Rep DecidedStrictness :: Type -> Type # Methods from :: DecidedStrictness -> Rep DecidedStrictness x # to :: Rep DecidedStrictness x -> DecidedStrictness #
Generic Undefined
Instance details Defined in Universum.Debug Associated Types type Rep Undefined :: Type -> Type # Methods from :: Undefined -> Rep Undefined x # to :: Rep Undefined x -> Undefined #
Generic [a]
Instance details Defined in GHC.Generics Associated Types type Rep [a] :: Type -> Type # Methods from :: [a] -> Rep [a] x # to :: Rep [a] x -> [a] #
Generic (Maybe a)
Instance details Defined in GHC.Generics Associated Types type Rep (Maybe a) :: Type -> Type # Methods from :: Maybe a -> Rep (Maybe a) x # to :: Rep (Maybe a) x -> Maybe a #
Generic (Par1 p)
Instance details Defined in GHC.Generics Associated Types type Rep (Par1 p) :: Type -> Type # Methods from :: Par1 p -> Rep (Par1 p) x # to :: Rep (Par1 p) x -> Par1 p #
Generic (Min a)
Instance details Defined in Data.Semigroup Associated Types type Rep (Min a) :: Type -> Type # Methods from :: Min a -> Rep (Min a) x # to :: Rep (Min a) x -> Min a #
Generic (Max a)
Instance details Defined in Data.Semigroup Associated Types type Rep (Max a) :: Type -> Type # Methods from :: Max a -> Rep (Max a) x # to :: Rep (Max a) x -> Max a #
Generic (First a)
Instance details Defined in Data.Semigroup Associated Types type Rep (First a) :: Type -> Type # Methods from :: First a -> Rep (First a) x # to :: Rep (First a) x -> First a #
Generic (Last a)
Instance details Defined in Data.Semigroup Associated Types type Rep (Last a) :: Type -> Type # Methods from :: Last a -> Rep (Last a) x # to :: Rep (Last a) x -> Last a #
Generic (WrappedMonoid m)
Instance details Defined in Data.Semigroup Associated Types type Rep (WrappedMonoid m) :: Type -> Type # Methods from :: WrappedMonoid m -> Rep (WrappedMonoid m) x # to :: Rep (WrappedMonoid m) x -> WrappedMonoid m #
Generic (Option a)
Instance details Defined in Data.Semigroup Associated Types type Rep (Option a) :: Type -> Type # Methods from :: Option a -> Rep (Option a) x # to :: Rep (Option a) x -> Option a #
Generic (ZipList a)
Instance details Defined in Control.Applicative Associated Types type Rep (ZipList a) :: Type -> Type # Methods from :: ZipList a -> Rep (ZipList a) x # to :: Rep (ZipList a) x -> ZipList a #
Generic (Identity a)
Instance details Defined in Data.Functor.Identity Associated Types type Rep (Identity a) :: Type -> Type # Methods from :: Identity a -> Rep (Identity a) x # to :: Rep (Identity a) x -> Identity a #
Generic (First a)
Instance details Defined in Data.Monoid Associated Types type Rep (First a) :: Type -> Type # Methods from :: First a -> Rep (First a) x # to :: Rep (First a) x -> First a #
Generic (Last a)
Instance details Defined in Data.Monoid Associated Types type Rep (Last a) :: Type -> Type # Methods from :: Last a -> Rep (Last a) x # to :: Rep (Last a) x -> Last a #
Generic (Dual a)
Instance details Defined in Data.Semigroup.Internal Associated Types type Rep (Dual a) :: Type -> Type # Methods from :: Dual a -> Rep (Dual a) x # to :: Rep (Dual a) x -> Dual a #
Generic (Endo a)
Instance details Defined in Data.Semigroup.Internal Associated Types type Rep (Endo a) :: Type -> Type # Methods from :: Endo a -> Rep (Endo a) x # to :: Rep (Endo a) x -> Endo a #
Generic (Sum a)
Instance details Defined in Data.Semigroup.Internal Associated Types type Rep (Sum a) :: Type -> Type # Methods from :: Sum a -> Rep (Sum a) x # to :: Rep (Sum a) x -> Sum a #
Generic (Product a)
Instance details Defined in Data.Semigroup.Internal Associated Types type Rep (Product a) :: Type -> Type # Methods from :: Product a -> Rep (Product a) x # to :: Rep (Product a) x -> Product a #
Generic (Down a)
Instance details Defined in GHC.Generics Associated Types type Rep (Down a) :: Type -> Type # Methods from :: Down a -> Rep (Down a) x # to :: Rep (Down a) x -> Down a #
Generic (NonEmpty a)
Instance details Defined in GHC.Generics Associated Types type Rep (NonEmpty a) :: Type -> Type # Methods from :: NonEmpty a -> Rep (NonEmpty a) x # to :: Rep (NonEmpty a) x -> NonEmpty a #
Generic (FingerTree a)
Instance details Defined in Data.Sequence.Internal Associated Types type Rep (FingerTree a) :: Type -> Type # Methods from :: FingerTree a -> Rep (FingerTree a) x # to :: Rep (FingerTree a) x -> FingerTree a #
Generic (Digit a)
Instance details Defined in Data.Sequence.Internal Associated Types type Rep (Digit a) :: Type -> Type # Methods from :: Digit a -> Rep (Digit a) x # to :: Rep (Digit a) x -> Digit a #
Generic (Node a)
Instance details Defined in Data.Sequence.Internal Associated Types type Rep (Node a) :: Type -> Type # Methods from :: Node a -> Rep (Node a) x # to :: Rep (Node a) x -> Node a #
Generic (Elem a)
Instance details Defined in Data.Sequence.Internal Associated Types type Rep (Elem a) :: Type -> Type # Methods from :: Elem a -> Rep (Elem a) x # to :: Rep (Elem a) x -> Elem a #
Generic (ViewL a)
Instance details Defined in Data.Sequence.Internal Associated Types type Rep (ViewL a) :: Type -> Type # Methods from :: ViewL a -> Rep (ViewL a) x # to :: Rep (ViewL a) x -> ViewL a #
Generic (ViewR a)
Instance details Defined in Data.Sequence.Internal Associated Types type Rep (ViewR a) :: Type -> Type # Methods from :: ViewR a -> Rep (ViewR a) x # to :: Rep (ViewR a) x -> ViewR a #
Generic (Either a b)
Instance details Defined in GHC.Generics Associated Types type Rep (Either a b) :: Type -> Type # Methods from :: Either a b -> Rep (Either a b) x # to :: Rep (Either a b) x -> Either a b #
Generic (V1 p)
Instance details Defined in GHC.Generics Associated Types type Rep (V1 p) :: Type -> Type # Methods from :: V1 p -> Rep (V1 p) x # to :: Rep (V1 p) x -> V1 p #
Generic (U1 p)
Instance details Defined in GHC.Generics Associated Types type Rep (U1 p) :: Type -> Type # Methods from :: U1 p -> Rep (U1 p) x # to :: Rep (U1 p) x -> U1 p #
Generic (a, b)
Instance details Defined in GHC.Generics Associated Types type Rep (a, b) :: Type -> Type # Methods from :: (a, b) -> Rep (a, b) x # to :: Rep (a, b) x -> (a, b) #
Generic (Arg a b)
Instance details Defined in Data.Semigroup Associated Types type Rep (Arg a b) :: Type -> Type # Methods from :: Arg a b -> Rep (Arg a b) x # to :: Rep (Arg a b) x -> Arg a b #
Generic (WrappedMonad m a)
Instance details Defined in Control.Applicative Associated Types type Rep (WrappedMonad m a) :: Type -> Type # Methods from :: WrappedMonad m a -> Rep (WrappedMonad m a) x # to :: Rep (WrappedMonad m a) x -> WrappedMonad m a #
Generic (Proxy t)
Instance details Defined in GHC.Generics Associated Types type Rep (Proxy t) :: Type -> Type # Methods from :: Proxy t -> Rep (Proxy t) x # to :: Rep (Proxy t) x -> Proxy t #
Generic (Rec1 f p)
Instance details Defined in GHC.Generics Associated Types type Rep (Rec1 f p) :: Type -> Type # Methods from :: Rec1 f p -> Rep (Rec1 f p) x # to :: Rep (Rec1 f p) x -> Rec1 f p #
Generic (URec (Ptr ()) p)
Instance details Defined in GHC.Generics Associated Types type Rep (URec (Ptr ()) p) :: Type -> Type # Methods from :: URec (Ptr ()) p -> Rep (URec (Ptr ()) p) x # to :: Rep (URec (Ptr ()) p) x -> URec (Ptr ()) p #
Generic (URec Char p)
Instance details Defined in GHC.Generics Associated Types type Rep (URec Char p) :: Type -> Type # Methods from :: URec Char p -> Rep (URec Char p) x # to :: Rep (URec Char p) x -> URec Char p #
Generic (URec Double p)
Instance details Defined in GHC.Generics Associated Types type Rep (URec Double p) :: Type -> Type # Methods from :: URec Double p -> Rep (URec Double p) x # to :: Rep (URec Double p) x -> URec Double p #
Generic (URec Float p)
Instance details Defined in GHC.Generics Associated Types type Rep (URec Float p) :: Type -> Type # Methods from :: URec Float p -> Rep (URec Float p) x # to :: Rep (URec Float p) x -> URec Float p #
Generic (URec Int p)
Instance details Defined in GHC.Generics Associated Types type Rep (URec Int p) :: Type -> Type # Methods from :: URec Int p -> Rep (URec Int p) x # to :: Rep (URec Int p) x -> URec Int p #
Generic (URec Word p)
Instance details Defined in GHC.Generics Associated Types type Rep (URec Word p) :: Type -> Type # Methods from :: URec Word p -> Rep (URec Word p) x # to :: Rep (URec Word p) x -> URec Word p #
Generic (a, b, c)
Instance details Defined in GHC.Generics Associated Types type Rep (a, b, c) :: Type -> Type # Methods from :: (a, b, c) -> Rep (a, b, c) x # to :: Rep (a, b, c) x -> (a, b, c) #
Generic (WrappedArrow a b c)
Instance details Defined in Control.Applicative Associated Types type Rep (WrappedArrow a b c) :: Type -> Type # Methods from :: WrappedArrow a b c -> Rep (WrappedArrow a b c) x # to :: Rep (WrappedArrow a b c) x -> WrappedArrow a b c #
Generic (Const a b)
Instance details Defined in Data.Functor.Const Associated Types type Rep (Const a b) :: Type -> Type # Methods from :: Const a b -> Rep (Const a b) x # to :: Rep (Const a b) x -> Const a b #
Generic (Ap f a)
Instance details Defined in Data.Monoid Associated Types type Rep (Ap f a) :: Type -> Type # Methods from :: Ap f a -> Rep (Ap f a) x # to :: Rep (Ap f a) x -> Ap f a #
Generic (Alt f a)
Instance details Defined in Data.Semigroup.Internal Associated Types type Rep (Alt f a) :: Type -> Type # Methods from :: Alt f a -> Rep (Alt f a) x # to :: Rep (Alt f a) x -> Alt f a #
Generic (K1 i c p)
Instance details Defined in GHC.Generics Associated Types type Rep (K1 i c p) :: Type -> Type # Methods from :: K1 i c p -> Rep (K1 i c p) x # to :: Rep (K1 i c p) x -> K1 i c p #
Generic ((f :+: g) p)
Instance details Defined in GHC.Generics Associated Types type Rep ((f :+: g) p) :: Type -> Type # Methods from :: (f :+: g) p -> Rep ((f :+: g) p) x # to :: Rep ((f :+: g) p) x -> (f :+: g) p #
Generic ((f :*: g) p)
Instance details Defined in GHC.Generics Associated Types type Rep ((f :: g) p) :: Type -> Type # Methods from :: (f :: g) p -> Rep ((f :: g) p) x # to :: Rep ((f :: g) p) x -> (f :*: g) p #
Generic (a, b, c, d)
Instance details Defined in GHC.Generics Associated Types type Rep (a, b, c, d) :: Type -> Type # Methods from :: (a, b, c, d) -> Rep (a, b, c, d) x # to :: Rep (a, b, c, d) x -> (a, b, c, d) #
Generic (M1 i c f p)
Instance details Defined in GHC.Generics Associated Types type Rep (M1 i c f p) :: Type -> Type # Methods from :: M1 i c f p -> Rep (M1 i c f p) x # to :: Rep (M1 i c f p) x -> M1 i c f p #
Generic ((f :.: g) p)
Instance details Defined in GHC.Generics Associated Types type Rep ((f :.: g) p) :: Type -> Type # Methods from :: (f :.: g) p -> Rep ((f :.: g) p) x # to :: Rep ((f :.: g) p) x -> (f :.: g) p #
Generic (a, b, c, d, e)
Instance details Defined in GHC.Generics Associated Types type Rep (a, b, c, d, e) :: Type -> Type # Methods from :: (a, b, c, d, e) -> Rep (a, b, c, d, e) x # to :: Rep (a, b, c, d, e) x -> (a, b, c, d, e) #
Generic (Compose f g a)
Instance details Defined in Data.Functor.Compose Associated Types type Rep (Compose f g a) :: Type -> Type # Methods from :: Compose f g a -> Rep (Compose f g a) x # to :: Rep (Compose f g a) x -> Compose f g a #
Generic (a, b, c, d, e, f)
Instance details Defined in GHC.Generics Associated Types type Rep (a, b, c, d, e, f) :: Type -> Type # Methods from :: (a, b, c, d, e, f) -> Rep (a, b, c, d, e, f) x # to :: Rep (a, b, c, d, e, f) x -> (a, b, c, d, e, f) #
Generic (a, b, c, d, e, f, g)
Instance details Defined in GHC.Generics Associated Types type Rep (a, b, c, d, e, f, g) :: Type -> Type # Methods from :: (a, b, c, d, e, f, g) -> Rep (a, b, c, d, e, f, g) x # to :: Rep (a, b, c, d, e, f, g) x -> (a, b, c, d, e, f, g) #

class KnownNat (n :: Nat) #

This class gives the integer associated with a type-level natural. There are instances of the class for every concrete literal: 0, 1, 2, etc.

Since: base-4.7.0.0

Minimal complete definition

natSing

class IsLabel (x :: Symbol) a where #

Methods

fromLabel :: a #

class Semigroup a where #

The class of semigroups (types with an associative binary operation).

Instances should satisfy the associativity law:

```
x <> (y <> z) = (x <> y) <> z
```

Since: base-4.9.0.0

Minimal complete definition

(<>)

Methods

(<>) :: a -> a -> a infixr 6 #

An associative operation.

sconcat :: NonEmpty a -> a #

Reduce a non-empty list with <>

The default definition should be sufficient, but this can be overridden for efficiency.

stimes :: Integral b => b -> a -> a #

Repeat a value n times.

Given that this works on a Semigroup it is allowed to fail if you request 0 or fewer repetitions, and the default definition will do so.

By making this a member of the class, idempotent semigroups and monoids can upgrade this to execute in O(1) by picking stimes = stimesIdempotent or stimes = stimesIdempotentMonoid respectively.

Instances

Semigroup Ordering	Since: base-4.9.0.0
Instance details Defined in GHC.Base Methods (<>) :: Ordering -> Ordering -> Ordering # sconcat :: NonEmpty Ordering -> Ordering # stimes :: Integral b => b -> Ordering -> Ordering #
Semigroup ()	Since: base-4.9.0.0
Instance details Defined in GHC.Base Methods (<>) :: () -> () -> () # sconcat :: NonEmpty () -> () # stimes :: Integral b => b -> () -> () #
Semigroup Void	Since: base-4.9.0.0
Instance details Defined in Data.Void Methods (<>) :: Void -> Void -> Void # sconcat :: NonEmpty Void -> Void # stimes :: Integral b => b -> Void -> Void #
Semigroup All	Since: base-4.9.0.0
Instance details Defined in Data.Semigroup.Internal Methods (<>) :: All -> All -> All # sconcat :: NonEmpty All -> All # stimes :: Integral b => b -> All -> All #
Semigroup Any	Since: base-4.9.0.0
Instance details Defined in Data.Semigroup.Internal Methods (<>) :: Any -> Any -> Any # sconcat :: NonEmpty Any -> Any # stimes :: Integral b => b -> Any -> Any #
Semigroup ByteString
Instance details Defined in Data.ByteString.Internal Methods (<>) :: ByteString -> ByteString -> ByteString # sconcat :: NonEmpty ByteString -> ByteString # stimes :: Integral b => b -> ByteString -> ByteString #
Semigroup IntSet	Since: containers-0.5.7
Instance details Defined in Data.IntSet.Internal Methods (<>) :: IntSet -> IntSet -> IntSet # sconcat :: NonEmpty IntSet -> IntSet # stimes :: Integral b => b -> IntSet -> IntSet #
Semigroup [a]	Since: base-4.9.0.0
Instance details Defined in GHC.Base Methods (<>) :: [a] -> [a] -> [a] # sconcat :: NonEmpty [a] -> [a] # stimes :: Integral b => b -> [a] -> [a] #
Semigroup a => Semigroup (Maybe a)	Since: base-4.9.0.0
Instance details Defined in GHC.Base Methods (<>) :: Maybe a -> Maybe a -> Maybe a # sconcat :: NonEmpty (Maybe a) -> Maybe a # stimes :: Integral b => b -> Maybe a -> Maybe a #
Semigroup a => Semigroup (IO a)	Since: base-4.10.0.0
Instance details Defined in GHC.Base Methods (<>) :: IO a -> IO a -> IO a # sconcat :: NonEmpty (IO a) -> IO a # stimes :: Integral b => b -> IO a -> IO a #
Semigroup p => Semigroup (Par1 p)	Since: base-4.12.0.0
Instance details Defined in GHC.Generics Methods (<>) :: Par1 p -> Par1 p -> Par1 p # sconcat :: NonEmpty (Par1 p) -> Par1 p # stimes :: Integral b => b -> Par1 p -> Par1 p #
Ord a => Semigroup (Min a)	Since: base-4.9.0.0
Instance details Defined in Data.Semigroup Methods (<>) :: Min a -> Min a -> Min a # sconcat :: NonEmpty (Min a) -> Min a # stimes :: Integral b => b -> Min a -> Min a #
Ord a => Semigroup (Max a)	Since: base-4.9.0.0
Instance details Defined in Data.Semigroup Methods (<>) :: Max a -> Max a -> Max a # sconcat :: NonEmpty (Max a) -> Max a # stimes :: Integral b => b -> Max a -> Max a #
Semigroup (First a)	Since: base-4.9.0.0
Instance details Defined in Data.Semigroup Methods (<>) :: First a -> First a -> First a # sconcat :: NonEmpty (First a) -> First a # stimes :: Integral b => b -> First a -> First a #
Semigroup (Last a)	Since: base-4.9.0.0
Instance details Defined in Data.Semigroup Methods (<>) :: Last a -> Last a -> Last a # sconcat :: NonEmpty (Last a) -> Last a # stimes :: Integral b => b -> Last a -> Last a #
Monoid m => Semigroup (WrappedMonoid m)	Since: base-4.9.0.0
Instance details Defined in Data.Semigroup Methods (<>) :: WrappedMonoid m -> WrappedMonoid m -> WrappedMonoid m # sconcat :: NonEmpty (WrappedMonoid m) -> WrappedMonoid m # stimes :: Integral b => b -> WrappedMonoid m -> WrappedMonoid m #
Semigroup a => Semigroup (Option a)	Since: base-4.9.0.0
Instance details Defined in Data.Semigroup Methods (<>) :: Option a -> Option a -> Option a # sconcat :: NonEmpty (Option a) -> Option a # stimes :: Integral b => b -> Option a -> Option a #
Semigroup a => Semigroup (Identity a)	Since: base-4.9.0.0
Instance details Defined in Data.Functor.Identity Methods (<>) :: Identity a -> Identity a -> Identity a # sconcat :: NonEmpty (Identity a) -> Identity a # stimes :: Integral b => b -> Identity a -> Identity a #
Semigroup (First a)	Since: base-4.9.0.0
Instance details Defined in Data.Monoid Methods (<>) :: First a -> First a -> First a # sconcat :: NonEmpty (First a) -> First a # stimes :: Integral b => b -> First a -> First a #
Semigroup (Last a)	Since: base-4.9.0.0
Instance details Defined in Data.Monoid Methods (<>) :: Last a -> Last a -> Last a # sconcat :: NonEmpty (Last a) -> Last a # stimes :: Integral b => b -> Last a -> Last a #
Semigroup a => Semigroup (Dual a)	Since: base-4.9.0.0
Instance details Defined in Data.Semigroup.Internal Methods (<>) :: Dual a -> Dual a -> Dual a # sconcat :: NonEmpty (Dual a) -> Dual a # stimes :: Integral b => b -> Dual a -> Dual a #
Semigroup (Endo a)	Since: base-4.9.0.0
Instance details Defined in Data.Semigroup.Internal Methods (<>) :: Endo a -> Endo a -> Endo a # sconcat :: NonEmpty (Endo a) -> Endo a # stimes :: Integral b => b -> Endo a -> Endo a #
Num a => Semigroup (Sum a)	Since: base-4.9.0.0
Instance details Defined in Data.Semigroup.Internal Methods (<>) :: Sum a -> Sum a -> Sum a # sconcat :: NonEmpty (Sum a) -> Sum a # stimes :: Integral b => b -> Sum a -> Sum a #
Num a => Semigroup (Product a)	Since: base-4.9.0.0
Instance details Defined in Data.Semigroup.Internal Methods (<>) :: Product a -> Product a -> Product a # sconcat :: NonEmpty (Product a) -> Product a # stimes :: Integral b => b -> Product a -> Product a #
Semigroup a => Semigroup (Down a)	Since: base-4.11.0.0
Instance details Defined in Data.Ord Methods (<>) :: Down a -> Down a -> Down a # sconcat :: NonEmpty (Down a) -> Down a # stimes :: Integral b => b -> Down a -> Down a #
Semigroup (NonEmpty a)	Since: base-4.9.0.0
Instance details Defined in GHC.Base Methods (<>) :: NonEmpty a -> NonEmpty a -> NonEmpty a # sconcat :: NonEmpty (NonEmpty a) -> NonEmpty a # stimes :: Integral b => b -> NonEmpty a -> NonEmpty a #
Semigroup (IntMap a)	Since: containers-0.5.7
Instance details Defined in Data.IntMap.Internal Methods (<>) :: IntMap a -> IntMap a -> IntMap a # sconcat :: NonEmpty (IntMap a) -> IntMap a # stimes :: Integral b => b -> IntMap a -> IntMap a #
Semigroup (Seq a)	Since: containers-0.5.7
Instance details Defined in Data.Sequence.Internal Methods (<>) :: Seq a -> Seq a -> Seq a # sconcat :: NonEmpty (Seq a) -> Seq a # stimes :: Integral b => b -> Seq a -> Seq a #
Ord a => Semigroup (Set a)	Since: containers-0.5.7
Instance details Defined in Data.Set.Internal Methods (<>) :: Set a -> Set a -> Set a # sconcat :: NonEmpty (Set a) -> Set a # stimes :: Integral b => b -> Set a -> Set a #
Semigroup (Vector a)
Instance details Defined in Data.Vector Methods (<>) :: Vector a -> Vector a -> Vector a # sconcat :: NonEmpty (Vector a) -> Vector a # stimes :: Integral b => b -> Vector a -> Vector a #
(Hashable a, Eq a) => Semigroup (HashSet a)
Instance details Defined in Data.HashSet.Base Methods (<>) :: HashSet a -> HashSet a -> HashSet a # sconcat :: NonEmpty (HashSet a) -> HashSet a # stimes :: Integral b => b -> HashSet a -> HashSet a #
Semigroup (MergeSet a)
Instance details Defined in Data.Set.Internal Methods (<>) :: MergeSet a -> MergeSet a -> MergeSet a # sconcat :: NonEmpty (MergeSet a) -> MergeSet a # stimes :: Integral b => b -> MergeSet a -> MergeSet a #
Semigroup b => Semigroup (a -> b)	Since: base-4.9.0.0
Instance details Defined in GHC.Base Methods (<>) :: (a -> b) -> (a -> b) -> a -> b # sconcat :: NonEmpty (a -> b) -> a -> b # stimes :: Integral b0 => b0 -> (a -> b) -> a -> b #
Semigroup (Either a b)	Since: base-4.9.0.0
Instance details Defined in Data.Either Methods (<>) :: Either a b -> Either a b -> Either a b # sconcat :: NonEmpty (Either a b) -> Either a b # stimes :: Integral b0 => b0 -> Either a b -> Either a b #
Semigroup (V1 p)	Since: base-4.12.0.0
Instance details Defined in GHC.Generics Methods (<>) :: V1 p -> V1 p -> V1 p # sconcat :: NonEmpty (V1 p) -> V1 p # stimes :: Integral b => b -> V1 p -> V1 p #
Semigroup (U1 p)	Since: base-4.12.0.0
Instance details Defined in GHC.Generics Methods (<>) :: U1 p -> U1 p -> U1 p # sconcat :: NonEmpty (U1 p) -> U1 p # stimes :: Integral b => b -> U1 p -> U1 p #
(Semigroup a, Semigroup b) => Semigroup (a, b)	Since: base-4.9.0.0
Instance details Defined in GHC.Base Methods (<>) :: (a, b) -> (a, b) -> (a, b) # sconcat :: NonEmpty (a, b) -> (a, b) # stimes :: Integral b0 => b0 -> (a, b) -> (a, b) #
Semigroup (Proxy s)	Since: base-4.9.0.0
Instance details Defined in Data.Proxy Methods (<>) :: Proxy s -> Proxy s -> Proxy s # sconcat :: NonEmpty (Proxy s) -> Proxy s # stimes :: Integral b => b -> Proxy s -> Proxy s #
Ord k => Semigroup (Map k v)
Instance details Defined in Data.Map.Internal Methods (<>) :: Map k v -> Map k v -> Map k v # sconcat :: NonEmpty (Map k v) -> Map k v # stimes :: Integral b => b -> Map k v -> Map k v #
(Eq k, Hashable k) => Semigroup (HashMap k v)
Instance details Defined in Data.HashMap.Base Methods (<>) :: HashMap k v -> HashMap k v -> HashMap k v # sconcat :: NonEmpty (HashMap k v) -> HashMap k v # stimes :: Integral b => b -> HashMap k v -> HashMap k v #
Applicative f => Semigroup (Traversed a f)
Instance details Defined in Lens.Micro Methods (<>) :: Traversed a f -> Traversed a f -> Traversed a f # sconcat :: NonEmpty (Traversed a f) -> Traversed a f # stimes :: Integral b => b -> Traversed a f -> Traversed a f #
Semigroup (f p) => Semigroup (Rec1 f p)	Since: base-4.12.0.0
Instance details Defined in GHC.Generics Methods (<>) :: Rec1 f p -> Rec1 f p -> Rec1 f p # sconcat :: NonEmpty (Rec1 f p) -> Rec1 f p # stimes :: Integral b => b -> Rec1 f p -> Rec1 f p #
(Semigroup a, Semigroup b, Semigroup c) => Semigroup (a, b, c)	Since: base-4.9.0.0
Instance details Defined in GHC.Base Methods (<>) :: (a, b, c) -> (a, b, c) -> (a, b, c) # sconcat :: NonEmpty (a, b, c) -> (a, b, c) # stimes :: Integral b0 => b0 -> (a, b, c) -> (a, b, c) #
Semigroup a => Semigroup (Const a b)	Since: base-4.9.0.0
Instance details Defined in Data.Functor.Const Methods (<>) :: Const a b -> Const a b -> Const a b # sconcat :: NonEmpty (Const a b) -> Const a b # stimes :: Integral b0 => b0 -> Const a b -> Const a b #
(Applicative f, Semigroup a) => Semigroup (Ap f a)	Since: base-4.12.0.0
Instance details Defined in Data.Monoid Methods (<>) :: Ap f a -> Ap f a -> Ap f a # sconcat :: NonEmpty (Ap f a) -> Ap f a # stimes :: Integral b => b -> Ap f a -> Ap f a #
Alternative f => Semigroup (Alt f a)	Since: base-4.9.0.0
Instance details Defined in Data.Semigroup.Internal Methods (<>) :: Alt f a -> Alt f a -> Alt f a # sconcat :: NonEmpty (Alt f a) -> Alt f a # stimes :: Integral b => b -> Alt f a -> Alt f a #
Semigroup c => Semigroup (K1 i c p)	Since: base-4.12.0.0
Instance details Defined in GHC.Generics Methods (<>) :: K1 i c p -> K1 i c p -> K1 i c p # sconcat :: NonEmpty (K1 i c p) -> K1 i c p # stimes :: Integral b => b -> K1 i c p -> K1 i c p #
(Semigroup (f p), Semigroup (g p)) => Semigroup ((f :*: g) p)	Since: base-4.12.0.0
Instance details Defined in GHC.Generics Methods (<>) :: (f :: g) p -> (f :: g) p -> (f :: g) p # sconcat :: NonEmpty ((f :: g) p) -> (f :: g) p # stimes :: Integral b => b -> (f :: g) p -> (f :*: g) p #
(Semigroup a, Semigroup b, Semigroup c, Semigroup d) => Semigroup (a, b, c, d)	Since: base-4.9.0.0
Instance details Defined in GHC.Base Methods (<>) :: (a, b, c, d) -> (a, b, c, d) -> (a, b, c, d) # sconcat :: NonEmpty (a, b, c, d) -> (a, b, c, d) # stimes :: Integral b0 => b0 -> (a, b, c, d) -> (a, b, c, d) #
Semigroup (f p) => Semigroup (M1 i c f p)	Since: base-4.12.0.0
Instance details Defined in GHC.Generics Methods (<>) :: M1 i c f p -> M1 i c f p -> M1 i c f p # sconcat :: NonEmpty (M1 i c f p) -> M1 i c f p # stimes :: Integral b => b -> M1 i c f p -> M1 i c f p #
Semigroup (f (g p)) => Semigroup ((f :.: g) p)	Since: base-4.12.0.0
Instance details Defined in GHC.Generics Methods (<>) :: (f :.: g) p -> (f :.: g) p -> (f :.: g) p # sconcat :: NonEmpty ((f :.: g) p) -> (f :.: g) p # stimes :: Integral b => b -> (f :.: g) p -> (f :.: g) p #
(Semigroup a, Semigroup b, Semigroup c, Semigroup d, Semigroup e) => Semigroup (a, b, c, d, e)	Since: base-4.9.0.0
Instance details Defined in GHC.Base Methods (<>) :: (a, b, c, d, e) -> (a, b, c, d, e) -> (a, b, c, d, e) # sconcat :: NonEmpty (a, b, c, d, e) -> (a, b, c, d, e) # stimes :: Integral b0 => b0 -> (a, b, c, d, e) -> (a, b, c, d, e) #

class Semigroup a => Monoid a where #

The class of monoids (types with an associative binary operation that has an identity). Instances should satisfy the following laws:

```
x <> mempty = x
```
```
mempty <> x = x
```
x <> (y <> z) = (x <> y) <> z (Semigroup law)
```
mconcat = foldr '(<>)' mempty
```

The method names refer to the monoid of lists under concatenation, but there are many other instances.

Some types can be viewed as a monoid in more than one way, e.g. both addition and multiplication on numbers. In such cases we often define newtypes and make those instances of Monoid, e.g. Sum and Product.

NOTE: Semigroup is a superclass of Monoid since base-4.11.0.0.

Minimal complete definition

mempty

Methods

mempty :: a #

Identity of mappend

mappend :: a -> a -> a #

An associative operation

NOTE: This method is redundant and has the default implementation mappend = '(<>)' since base-4.11.0.0.

mconcat :: [a] -> a #

Fold a list using the monoid.

For most types, the default definition for mconcat will be used, but the function is included in the class definition so that an optimized version can be provided for specific types.

Instances

Monoid Ordering	Since: base-2.1
Instance details Defined in GHC.Base Methods mempty :: Ordering # mappend :: Ordering -> Ordering -> Ordering # mconcat :: [Ordering] -> Ordering #
Monoid ()	Since: base-2.1
Instance details Defined in GHC.Base Methods mempty :: () # mappend :: () -> () -> () # mconcat :: [()] -> () #
Monoid All	Since: base-2.1
Instance details Defined in Data.Semigroup.Internal Methods mempty :: All # mappend :: All -> All -> All # mconcat :: [All] -> All #
Monoid Any	Since: base-2.1
Instance details Defined in Data.Semigroup.Internal Methods mempty :: Any # mappend :: Any -> Any -> Any # mconcat :: [Any] -> Any #
Monoid ByteString
Instance details Defined in Data.ByteString.Internal Methods mempty :: ByteString # mappend :: ByteString -> ByteString -> ByteString # mconcat :: [ByteString] -> ByteString #
Monoid IntSet
Instance details Defined in Data.IntSet.Internal Methods mempty :: IntSet # mappend :: IntSet -> IntSet -> IntSet # mconcat :: [IntSet] -> IntSet #
Monoid [a]	Since: base-2.1
Instance details Defined in GHC.Base Methods mempty :: [a] # mappend :: [a] -> [a] -> [a] # mconcat :: [[a]] -> [a] #
Semigroup a => Monoid (Maybe a)	Lift a semigroup into `Maybe` forming a `Monoid` according to http://en.wikipedia.org/wiki/Monoid: "Any semigroup `S` may be turned into a monoid simply by adjoining an element `e` not in `S` and defining `ee = e` and `es = s = se` for all `s ∈ S`." Since 4.11.0: constraint on inner `a` value generalised from `Monoid` to `Semigroup`. Since: base-2.1*
Instance details Defined in GHC.Base Methods mempty :: Maybe a # mappend :: Maybe a -> Maybe a -> Maybe a # mconcat :: [Maybe a] -> Maybe a #
Monoid a => Monoid (IO a)	Since: base-4.9.0.0
Instance details Defined in GHC.Base Methods mempty :: IO a # mappend :: IO a -> IO a -> IO a # mconcat :: [IO a] -> IO a #
Monoid p => Monoid (Par1 p)	Since: base-4.12.0.0
Instance details Defined in GHC.Generics Methods mempty :: Par1 p # mappend :: Par1 p -> Par1 p -> Par1 p # mconcat :: [Par1 p] -> Par1 p #
(Ord a, Bounded a) => Monoid (Min a)	Since: base-4.9.0.0
Instance details Defined in Data.Semigroup Methods mempty :: Min a # mappend :: Min a -> Min a -> Min a # mconcat :: [Min a] -> Min a #
(Ord a, Bounded a) => Monoid (Max a)	Since: base-4.9.0.0
Instance details Defined in Data.Semigroup Methods mempty :: Max a # mappend :: Max a -> Max a -> Max a # mconcat :: [Max a] -> Max a #
Monoid m => Monoid (WrappedMonoid m)	Since: base-4.9.0.0
Instance details Defined in Data.Semigroup Methods mempty :: WrappedMonoid m # mappend :: WrappedMonoid m -> WrappedMonoid m -> WrappedMonoid m # mconcat :: [WrappedMonoid m] -> WrappedMonoid m #
Semigroup a => Monoid (Option a)	Since: base-4.9.0.0
Instance details Defined in Data.Semigroup Methods mempty :: Option a # mappend :: Option a -> Option a -> Option a # mconcat :: [Option a] -> Option a #
Monoid a => Monoid (Identity a)	Since: base-4.9.0.0
Instance details Defined in Data.Functor.Identity Methods mempty :: Identity a # mappend :: Identity a -> Identity a -> Identity a # mconcat :: [Identity a] -> Identity a #
Monoid (First a)	Since: base-2.1
Instance details Defined in Data.Monoid Methods mempty :: First a # mappend :: First a -> First a -> First a # mconcat :: [First a] -> First a #
Monoid (Last a)	Since: base-2.1
Instance details Defined in Data.Monoid Methods mempty :: Last a # mappend :: Last a -> Last a -> Last a # mconcat :: [Last a] -> Last a #
Monoid a => Monoid (Dual a)	Since: base-2.1
Instance details Defined in Data.Semigroup.Internal Methods mempty :: Dual a # mappend :: Dual a -> Dual a -> Dual a # mconcat :: [Dual a] -> Dual a #
Monoid (Endo a)	Since: base-2.1
Instance details Defined in Data.Semigroup.Internal Methods mempty :: Endo a # mappend :: Endo a -> Endo a -> Endo a # mconcat :: [Endo a] -> Endo a #
Num a => Monoid (Sum a)	Since: base-2.1
Instance details Defined in Data.Semigroup.Internal Methods mempty :: Sum a # mappend :: Sum a -> Sum a -> Sum a # mconcat :: [Sum a] -> Sum a #
Num a => Monoid (Product a)	Since: base-2.1
Instance details Defined in Data.Semigroup.Internal Methods mempty :: Product a # mappend :: Product a -> Product a -> Product a # mconcat :: [Product a] -> Product a #
Monoid a => Monoid (Down a)	Since: base-4.11.0.0
Instance details Defined in Data.Ord Methods mempty :: Down a # mappend :: Down a -> Down a -> Down a # mconcat :: [Down a] -> Down a #
Monoid (IntMap a)
Instance details Defined in Data.IntMap.Internal Methods mempty :: IntMap a # mappend :: IntMap a -> IntMap a -> IntMap a # mconcat :: [IntMap a] -> IntMap a #
Monoid (Seq a)
Instance details Defined in Data.Sequence.Internal Methods mempty :: Seq a # mappend :: Seq a -> Seq a -> Seq a # mconcat :: [Seq a] -> Seq a #
Ord a => Monoid (Set a)
Instance details Defined in Data.Set.Internal Methods mempty :: Set a # mappend :: Set a -> Set a -> Set a # mconcat :: [Set a] -> Set a #
Monoid (Vector a)
Instance details Defined in Data.Vector Methods mempty :: Vector a # mappend :: Vector a -> Vector a -> Vector a # mconcat :: [Vector a] -> Vector a #
(Hashable a, Eq a) => Monoid (HashSet a)
Instance details Defined in Data.HashSet.Base Methods mempty :: HashSet a # mappend :: HashSet a -> HashSet a -> HashSet a # mconcat :: [HashSet a] -> HashSet a #
Monoid (MergeSet a)
Instance details Defined in Data.Set.Internal Methods mempty :: MergeSet a # mappend :: MergeSet a -> MergeSet a -> MergeSet a # mconcat :: [MergeSet a] -> MergeSet a #
Monoid b => Monoid (a -> b)	Since: base-2.1
Instance details Defined in GHC.Base Methods mempty :: a -> b # mappend :: (a -> b) -> (a -> b) -> a -> b # mconcat :: [a -> b] -> a -> b #
Monoid (U1 p)	Since: base-4.12.0.0
Instance details Defined in GHC.Generics Methods mempty :: U1 p # mappend :: U1 p -> U1 p -> U1 p # mconcat :: [U1 p] -> U1 p #
(Monoid a, Monoid b) => Monoid (a, b)	Since: base-2.1
Instance details Defined in GHC.Base Methods mempty :: (a, b) # mappend :: (a, b) -> (a, b) -> (a, b) # mconcat :: [(a, b)] -> (a, b) #
Monoid (Proxy s)	Since: base-4.7.0.0
Instance details Defined in Data.Proxy Methods mempty :: Proxy s # mappend :: Proxy s -> Proxy s -> Proxy s # mconcat :: [Proxy s] -> Proxy s #
Ord k => Monoid (Map k v)
Instance details Defined in Data.Map.Internal Methods mempty :: Map k v # mappend :: Map k v -> Map k v -> Map k v # mconcat :: [Map k v] -> Map k v #
(Eq k, Hashable k) => Monoid (HashMap k v)
Instance details Defined in Data.HashMap.Base Methods mempty :: HashMap k v # mappend :: HashMap k v -> HashMap k v -> HashMap k v # mconcat :: [HashMap k v] -> HashMap k v #
Applicative f => Monoid (Traversed a f)
Instance details Defined in Lens.Micro Methods mempty :: Traversed a f # mappend :: Traversed a f -> Traversed a f -> Traversed a f # mconcat :: [Traversed a f] -> Traversed a f #
Monoid (f p) => Monoid (Rec1 f p)	Since: base-4.12.0.0
Instance details Defined in GHC.Generics Methods mempty :: Rec1 f p # mappend :: Rec1 f p -> Rec1 f p -> Rec1 f p # mconcat :: [Rec1 f p] -> Rec1 f p #
(Monoid a, Monoid b, Monoid c) => Monoid (a, b, c)	Since: base-2.1
Instance details Defined in GHC.Base Methods mempty :: (a, b, c) # mappend :: (a, b, c) -> (a, b, c) -> (a, b, c) # mconcat :: [(a, b, c)] -> (a, b, c) #
Monoid a => Monoid (Const a b)	Since: base-4.9.0.0
Instance details Defined in Data.Functor.Const Methods mempty :: Const a b # mappend :: Const a b -> Const a b -> Const a b # mconcat :: [Const a b] -> Const a b #
(Applicative f, Monoid a) => Monoid (Ap f a)	Since: base-4.12.0.0
Instance details Defined in Data.Monoid Methods mempty :: Ap f a # mappend :: Ap f a -> Ap f a -> Ap f a # mconcat :: [Ap f a] -> Ap f a #
Alternative f => Monoid (Alt f a)	Since: base-4.8.0.0
Instance details Defined in Data.Semigroup.Internal Methods mempty :: Alt f a # mappend :: Alt f a -> Alt f a -> Alt f a # mconcat :: [Alt f a] -> Alt f a #
Monoid c => Monoid (K1 i c p)	Since: base-4.12.0.0
Instance details Defined in GHC.Generics Methods mempty :: K1 i c p # mappend :: K1 i c p -> K1 i c p -> K1 i c p # mconcat :: [K1 i c p] -> K1 i c p #
(Monoid (f p), Monoid (g p)) => Monoid ((f :*: g) p)	Since: base-4.12.0.0
Instance details Defined in GHC.Generics Methods mempty :: (f :: g) p # mappend :: (f :: g) p -> (f :: g) p -> (f :: g) p # mconcat :: [(f :: g) p] -> (f :: g) p #
(Monoid a, Monoid b, Monoid c, Monoid d) => Monoid (a, b, c, d)	Since: base-2.1
Instance details Defined in GHC.Base Methods mempty :: (a, b, c, d) # mappend :: (a, b, c, d) -> (a, b, c, d) -> (a, b, c, d) # mconcat :: [(a, b, c, d)] -> (a, b, c, d) #
Monoid (f p) => Monoid (M1 i c f p)	Since: base-4.12.0.0
Instance details Defined in GHC.Generics Methods mempty :: M1 i c f p # mappend :: M1 i c f p -> M1 i c f p -> M1 i c f p # mconcat :: [M1 i c f p] -> M1 i c f p #
Monoid (f (g p)) => Monoid ((f :.: g) p)	Since: base-4.12.0.0
Instance details Defined in GHC.Generics Methods mempty :: (f :.: g) p # mappend :: (f :.: g) p -> (f :.: g) p -> (f :.: g) p # mconcat :: [(f :.: g) p] -> (f :.: g) p #
(Monoid a, Monoid b, Monoid c, Monoid d, Monoid e) => Monoid (a, b, c, d, e)	Since: base-2.1
Instance details Defined in GHC.Base Methods mempty :: (a, b, c, d, e) # mappend :: (a, b, c, d, e) -> (a, b, c, d, e) -> (a, b, c, d, e) # mconcat :: [(a, b, c, d, e)] -> (a, b, c, d, e) #

data Bool #

Constructors

False
True

Instances

Bounded Bool	Since: base-2.1
Instance details Defined in GHC.Enum Methods minBound :: Bool # maxBound :: Bool #
Enum Bool	Since: base-2.1
Instance details Defined in GHC.Enum Methods succ :: Bool -> Bool # pred :: Bool -> Bool # toEnum :: Int -> Bool # fromEnum :: Bool -> Int # enumFrom :: Bool -> [Bool] # enumFromThen :: Bool -> Bool -> [Bool] # enumFromTo :: Bool -> Bool -> [Bool] # enumFromThenTo :: Bool -> Bool -> Bool -> [Bool] #
Eq Bool
Instance details Defined in GHC.Classes Methods (==) :: Bool -> Bool -> Bool # (/=) :: Bool -> Bool -> Bool #
Ord Bool
Instance details Defined in GHC.Classes Methods compare :: Bool -> Bool -> Ordering # (<) :: Bool -> Bool -> Bool # (<=) :: Bool -> Bool -> Bool # (>) :: Bool -> Bool -> Bool # (>=) :: Bool -> Bool -> Bool # max :: Bool -> Bool -> Bool # min :: Bool -> Bool -> Bool #
Read Bool	Since: base-2.1
Instance details Defined in GHC.Read Methods readsPrec :: Int -> ReadS Bool # readList :: ReadS [Bool] # readPrec :: ReadPrec Bool # readListPrec :: ReadPrec [Bool] #
Show Bool	Since: base-2.1
Instance details Defined in GHC.Show Methods showsPrec :: Int -> Bool -> ShowS # show :: Bool -> String # showList :: [Bool] -> ShowS #
Generic Bool
Instance details Defined in GHC.Generics Associated Types type Rep Bool :: Type -> Type # Methods from :: Bool -> Rep Bool x # to :: Rep Bool x -> Bool #
SingKind Bool	Since: base-4.9.0.0
Instance details Defined in GHC.Generics Associated Types type DemoteRep Bool :: Type Methods fromSing :: Sing a -> DemoteRep Bool
Bits Bool	Interpret `Bool` as 1-bit bit-field Since: base-4.7.0.0
Instance details Defined in Data.Bits Methods (.&.) :: Bool -> Bool -> Bool # (.\|.) :: Bool -> Bool -> Bool # xor :: Bool -> Bool -> Bool # complement :: Bool -> Bool # shift :: Bool -> Int -> Bool # rotate :: Bool -> Int -> Bool # zeroBits :: Bool # bit :: Int -> Bool # setBit :: Bool -> Int -> Bool # clearBit :: Bool -> Int -> Bool # complementBit :: Bool -> Int -> Bool # testBit :: Bool -> Int -> Bool # bitSizeMaybe :: Bool -> Maybe Int # bitSize :: Bool -> Int # isSigned :: Bool -> Bool # shiftL :: Bool -> Int -> Bool # unsafeShiftL :: Bool -> Int -> Bool # shiftR :: Bool -> Int -> Bool # unsafeShiftR :: Bool -> Int -> Bool # rotateL :: Bool -> Int -> Bool # rotateR :: Bool -> Int -> Bool # popCount :: Bool -> Int #
FiniteBits Bool	Since: base-4.7.0.0
Instance details Defined in Data.Bits Methods finiteBitSize :: Bool -> Int # countLeadingZeros :: Bool -> Int # countTrailingZeros :: Bool -> Int #
NFData Bool
Instance details Defined in Control.DeepSeq Methods rnf :: Bool -> () #
Hashable Bool
Instance details Defined in Data.Hashable.Class Methods hashWithSalt :: Int -> Bool -> Int # hash :: Bool -> Int #
SingI False	Since: base-4.9.0.0
Instance details Defined in GHC.Generics Methods sing :: Sing False
SingI True	Since: base-4.9.0.0
Instance details Defined in GHC.Generics Methods sing :: Sing True
type Rep Bool	Since: base-4.6.0.0
Instance details Defined in GHC.Generics type Rep Bool = D1 (MetaData "Bool" "GHC.Types" "ghc-prim" False) (C1 (MetaCons "False" PrefixI False) (U1 :: Type -> Type) :+: C1 (MetaCons "True" PrefixI False) (U1 :: Type -> Type))
data Sing (a :: Bool)
Instance details Defined in GHC.Generics data Sing (a :: Bool) where STrue :: forall (a :: Bool). Sing True SFalse :: forall (a :: Bool). Sing False
type DemoteRep Bool
Instance details Defined in GHC.Generics type DemoteRep Bool = Bool

data Char #

The character type Char is an enumeration whose values represent Unicode (or equivalently ISO/IEC 10646) code points (i.e. characters, see http://www.unicode.org/ for details). This set extends the ISO 8859-1 (Latin-1) character set (the first 256 characters), which is itself an extension of the ASCII character set (the first 128 characters). A character literal in Haskell has type Char.

To convert a Char to or from the corresponding Int value defined by Unicode, use toEnum and fromEnum from the Enum class respectively (or equivalently ord and chr).

Instances

Bounded Char	Since: base-2.1
Instance details Defined in GHC.Enum Methods minBound :: Char # maxBound :: Char #
Enum Char	Since: base-2.1
Instance details Defined in GHC.Enum Methods succ :: Char -> Char # pred :: Char -> Char # toEnum :: Int -> Char # fromEnum :: Char -> Int # enumFrom :: Char -> [Char] # enumFromThen :: Char -> Char -> [Char] # enumFromTo :: Char -> Char -> [Char] # enumFromThenTo :: Char -> Char -> Char -> [Char] #
Eq Char
Instance details Defined in GHC.Classes Methods (==) :: Char -> Char -> Bool # (/=) :: Char -> Char -> Bool #
Ord Char
Instance details Defined in GHC.Classes Methods compare :: Char -> Char -> Ordering # (<) :: Char -> Char -> Bool # (<=) :: Char -> Char -> Bool # (>) :: Char -> Char -> Bool # (>=) :: Char -> Char -> Bool # max :: Char -> Char -> Char # min :: Char -> Char -> Char #
Read Char	Since: base-2.1
Instance details Defined in GHC.Read Methods readsPrec :: Int -> ReadS Char # readList :: ReadS [Char] # readPrec :: ReadPrec Char # readListPrec :: ReadPrec [Char] #
Show Char	Since: base-2.1
Instance details Defined in GHC.Show Methods showsPrec :: Int -> Char -> ShowS # show :: Char -> String # showList :: [Char] -> ShowS #
NFData Char
Instance details Defined in Control.DeepSeq Methods rnf :: Char -> () #
Hashable Char
Instance details Defined in Data.Hashable.Class Methods hashWithSalt :: Int -> Char -> Int # hash :: Char -> Int #
ErrorList Char
Instance details Defined in Control.Monad.Trans.Error Methods listMsg :: String -> [Char] #
ToText String
Instance details Defined in Universum.String.Conversion Methods toText :: String -> Text #
ToLText String
Instance details Defined in Universum.String.Conversion Methods toLText :: String -> Text #
ToString String
Instance details Defined in Universum.String.Conversion Methods toString :: String -> String #
ConvertUtf8 String ByteString
Instance details Defined in Universum.String.Conversion Methods encodeUtf8 :: String -> ByteString # decodeUtf8 :: ByteString -> String # decodeUtf8Strict :: ByteString -> Either UnicodeException String #
ConvertUtf8 String ByteString
Instance details Defined in Universum.String.Conversion Methods encodeUtf8 :: String -> ByteString # decodeUtf8 :: ByteString -> String # decodeUtf8Strict :: ByteString -> Either UnicodeException String #
Generic1 (URec Char :: k -> Type)
Instance details Defined in GHC.Generics Associated Types type Rep1 (URec Char) :: k -> Type # Methods from1 :: URec Char a -> Rep1 (URec Char) a # to1 :: Rep1 (URec Char) a -> URec Char a #
Print [Char]
Instance details Defined in Universum.Print.Internal Methods hPutStr :: Handle -> [Char] -> IO () # hPutStrLn :: Handle -> [Char] -> IO () #
Functor (URec Char :: Type -> Type)	Since: base-4.9.0.0
Instance details Defined in GHC.Generics Methods fmap :: (a -> b) -> URec Char a -> URec Char b # (<$) :: a -> URec Char b -> URec Char a #
Foldable (URec Char :: Type -> Type)	Since: base-4.9.0.0
Instance details Defined in Data.Foldable Methods fold :: Monoid m => URec Char m -> m # foldMap :: Monoid m => (a -> m) -> URec Char a -> m # foldr :: (a -> b -> b) -> b -> URec Char a -> b # foldr' :: (a -> b -> b) -> b -> URec Char a -> b # foldl :: (b -> a -> b) -> b -> URec Char a -> b # foldl' :: (b -> a -> b) -> b -> URec Char a -> b # foldr1 :: (a -> a -> a) -> URec Char a -> a # foldl1 :: (a -> a -> a) -> URec Char a -> a # toList :: URec Char a -> [a] # null :: URec Char a -> Bool # length :: URec Char a -> Int # elem :: Eq a => a -> URec Char a -> Bool # maximum :: Ord a => URec Char a -> a # minimum :: Ord a => URec Char a -> a # sum :: Num a => URec Char a -> a # product :: Num a => URec Char a -> a #
Traversable (URec Char :: Type -> Type)	Since: base-4.9.0.0
Instance details Defined in Data.Traversable Methods traverse :: Applicative f => (a -> f b) -> URec Char a -> f (URec Char b) # sequenceA :: Applicative f => URec Char (f a) -> f (URec Char a) # mapM :: Monad m => (a -> m b) -> URec Char a -> m (URec Char b) # sequence :: Monad m => URec Char (m a) -> m (URec Char a) #
Eq (URec Char p)	Since: base-4.9.0.0
Instance details Defined in GHC.Generics Methods (==) :: URec Char p -> URec Char p -> Bool # (/=) :: URec Char p -> URec Char p -> Bool #
Ord (URec Char p)	Since: base-4.9.0.0
Instance details Defined in GHC.Generics Methods compare :: URec Char p -> URec Char p -> Ordering # (<) :: URec Char p -> URec Char p -> Bool # (<=) :: URec Char p -> URec Char p -> Bool # (>) :: URec Char p -> URec Char p -> Bool # (>=) :: URec Char p -> URec Char p -> Bool # max :: URec Char p -> URec Char p -> URec Char p # min :: URec Char p -> URec Char p -> URec Char p #
Show (URec Char p)	Since: base-4.9.0.0
Instance details Defined in GHC.Generics Methods showsPrec :: Int -> URec Char p -> ShowS # show :: URec Char p -> String # showList :: [URec Char p] -> ShowS #
Generic (URec Char p)
Instance details Defined in GHC.Generics Associated Types type Rep (URec Char p) :: Type -> Type # Methods from :: URec Char p -> Rep (URec Char p) x # to :: Rep (URec Char p) x -> URec Char p #
data URec Char (p :: k)	Used for marking occurrences of `Char#` Since: base-4.9.0.0
Instance details Defined in GHC.Generics data URec Char (p :: k) = UChar { uChar# :: Char# }
type Rep1 (URec Char :: k -> Type)	Since: base-4.9.0.0
Instance details Defined in GHC.Generics type Rep1 (URec Char :: k -> Type) = D1 (MetaData "URec" "GHC.Generics" "base" False) (C1 (MetaCons "UChar" PrefixI True) (S1 (MetaSel (Just "uChar#") NoSourceUnpackedness NoSourceStrictness DecidedLazy) (UChar :: k -> Type)))
type Rep (URec Char p)	Since: base-4.9.0.0
Instance details Defined in GHC.Generics type Rep (URec Char p) = D1 (MetaData "URec" "GHC.Generics" "base" False) (C1 (MetaCons "UChar" PrefixI True) (S1 (MetaSel (Just "uChar#") NoSourceUnpackedness NoSourceStrictness DecidedLazy) (UChar :: Type -> Type)))

data Double #

Double-precision floating point numbers. It is desirable that this type be at least equal in range and precision to the IEEE double-precision type.

Constructors

D# Double#

Instances

Eq Double	Note that due to the presence of `NaN`, `Double`'s `Eq` instance does not satisfy reflexivity. `>>>` `0/0 == (0/0 :: Double)`False Also note that `Double`'s `Eq` instance does not satisfy substitutivity: `>>>` `0 == (-0 :: Double)`True `>>>` `recip 0 == recip (-0 :: Double)`False
Instance details Defined in GHC.Classes Methods (==) :: Double -> Double -> Bool # (/=) :: Double -> Double -> Bool #
Floating Double	Since: base-2.1
Instance details Defined in GHC.Float Methods pi :: Double # exp :: Double -> Double # log :: Double -> Double # sqrt :: Double -> Double # (**) :: Double -> Double -> Double # logBase :: Double -> Double -> Double # sin :: Double -> Double # cos :: Double -> Double # tan :: Double -> Double # asin :: Double -> Double # acos :: Double -> Double # atan :: Double -> Double # sinh :: Double -> Double # cosh :: Double -> Double # tanh :: Double -> Double # asinh :: Double -> Double # acosh :: Double -> Double # atanh :: Double -> Double # log1p :: Double -> Double # expm1 :: Double -> Double # log1pexp :: Double -> Double # log1mexp :: Double -> Double #
Ord Double	Note that due to the presence of `NaN`, `Double`'s `Ord` instance does not satisfy reflexivity. `>>>` `0/0 <= (0/0 :: Double)`False Also note that, due to the same, `Ord`'s operator interactions are not respected by `Double`'s instance: `>>>` `(0/0 :: Double) > 1`False `>>>` `compare (0/0 :: Double) 1`GT
Instance details Defined in GHC.Classes Methods compare :: Double -> Double -> Ordering # (<) :: Double -> Double -> Bool # (<=) :: Double -> Double -> Bool # (>) :: Double -> Double -> Bool # (>=) :: Double -> Double -> Bool # max :: Double -> Double -> Double # min :: Double -> Double -> Double #
Read Double	Since: base-2.1
Instance details Defined in GHC.Read Methods readsPrec :: Int -> ReadS Double # readList :: ReadS [Double] # readPrec :: ReadPrec Double # readListPrec :: ReadPrec [Double] #
RealFloat Double	Since: base-2.1
Instance details Defined in GHC.Float Methods floatRadix :: Double -> Integer # floatDigits :: Double -> Int # floatRange :: Double -> (Int, Int) # decodeFloat :: Double -> (Integer, Int) # encodeFloat :: Integer -> Int -> Double # exponent :: Double -> Int # significand :: Double -> Double # scaleFloat :: Int -> Double -> Double # isNaN :: Double -> Bool # isInfinite :: Double -> Bool # isDenormalized :: Double -> Bool # isNegativeZero :: Double -> Bool # isIEEE :: Double -> Bool # atan2 :: Double -> Double -> Double #
NFData Double
Instance details Defined in Control.DeepSeq Methods rnf :: Double -> () #
Hashable Double	Note: prior to `hashable-1.3.0.0`, `hash 0.0 /= hash (-0.0)` The `hash` of NaN is not well defined. Since: hashable-1.3.0.0
Instance details Defined in Data.Hashable.Class Methods hashWithSalt :: Int -> Double -> Int # hash :: Double -> Int #
Generic1 (URec Double :: k -> Type)
Instance details Defined in GHC.Generics Associated Types type Rep1 (URec Double) :: k -> Type # Methods from1 :: URec Double a -> Rep1 (URec Double) a # to1 :: Rep1 (URec Double) a -> URec Double a #
Functor (URec Double :: Type -> Type)	Since: base-4.9.0.0
Instance details Defined in GHC.Generics Methods fmap :: (a -> b) -> URec Double a -> URec Double b # (<$) :: a -> URec Double b -> URec Double a #
Foldable (URec Double :: Type -> Type)	Since: base-4.9.0.0
Instance details Defined in Data.Foldable Methods fold :: Monoid m => URec Double m -> m # foldMap :: Monoid m => (a -> m) -> URec Double a -> m # foldr :: (a -> b -> b) -> b -> URec Double a -> b # foldr' :: (a -> b -> b) -> b -> URec Double a -> b # foldl :: (b -> a -> b) -> b -> URec Double a -> b # foldl' :: (b -> a -> b) -> b -> URec Double a -> b # foldr1 :: (a -> a -> a) -> URec Double a -> a # foldl1 :: (a -> a -> a) -> URec Double a -> a # toList :: URec Double a -> [a] # null :: URec Double a -> Bool # length :: URec Double a -> Int # elem :: Eq a => a -> URec Double a -> Bool # maximum :: Ord a => URec Double a -> a # minimum :: Ord a => URec Double a -> a # sum :: Num a => URec Double a -> a # product :: Num a => URec Double a -> a #
Traversable (URec Double :: Type -> Type)	Since: base-4.9.0.0
Instance details Defined in Data.Traversable Methods traverse :: Applicative f => (a -> f b) -> URec Double a -> f (URec Double b) # sequenceA :: Applicative f => URec Double (f a) -> f (URec Double a) # mapM :: Monad m => (a -> m b) -> URec Double a -> m (URec Double b) # sequence :: Monad m => URec Double (m a) -> m (URec Double a) #
Eq (URec Double p)	Since: base-4.9.0.0
Instance details Defined in GHC.Generics Methods (==) :: URec Double p -> URec Double p -> Bool # (/=) :: URec Double p -> URec Double p -> Bool #
Ord (URec Double p)	Since: base-4.9.0.0
Instance details Defined in GHC.Generics Methods compare :: URec Double p -> URec Double p -> Ordering # (<) :: URec Double p -> URec Double p -> Bool # (<=) :: URec Double p -> URec Double p -> Bool # (>) :: URec Double p -> URec Double p -> Bool # (>=) :: URec Double p -> URec Double p -> Bool # max :: URec Double p -> URec Double p -> URec Double p # min :: URec Double p -> URec Double p -> URec Double p #
Show (URec Double p)	Since: base-4.9.0.0
Instance details Defined in GHC.Generics Methods showsPrec :: Int -> URec Double p -> ShowS # show :: URec Double p -> String # showList :: [URec Double p] -> ShowS #
Generic (URec Double p)
Instance details Defined in GHC.Generics Associated Types type Rep (URec Double p) :: Type -> Type # Methods from :: URec Double p -> Rep (URec Double p) x # to :: Rep (URec Double p) x -> URec Double p #
data URec Double (p :: k)	Used for marking occurrences of `Double#` Since: base-4.9.0.0
Instance details Defined in GHC.Generics data URec Double (p :: k) = UDouble { uDouble# :: Double# }
type Rep1 (URec Double :: k -> Type)	Since: base-4.9.0.0
Instance details Defined in GHC.Generics type Rep1 (URec Double :: k -> Type) = D1 (MetaData "URec" "GHC.Generics" "base" False) (C1 (MetaCons "UDouble" PrefixI True) (S1 (MetaSel (Just "uDouble#") NoSourceUnpackedness NoSourceStrictness DecidedLazy) (UDouble :: k -> Type)))
type Rep (URec Double p)	Since: base-4.9.0.0
Instance details Defined in GHC.Generics type Rep (URec Double p) = D1 (MetaData "URec" "GHC.Generics" "base" False) (C1 (MetaCons "UDouble" PrefixI True) (S1 (MetaSel (Just "uDouble#") NoSourceUnpackedness NoSourceStrictness DecidedLazy) (UDouble :: Type -> Type)))

data Float #

Single-precision floating point numbers. It is desirable that this type be at least equal in range and precision to the IEEE single-precision type.

Constructors

F# Float#

Instances

Eq Float	Note that due to the presence of `NaN`, `Float`'s `Eq` instance does not satisfy reflexivity. `>>>` `0/0 == (0/0 :: Float)`False Also note that `Float`'s `Eq` instance does not satisfy substitutivity: `>>>` `0 == (-0 :: Float)`True `>>>` `recip 0 == recip (-0 :: Float)`False
Instance details Defined in GHC.Classes Methods (==) :: Float -> Float -> Bool # (/=) :: Float -> Float -> Bool #
Floating Float	Since: base-2.1
Instance details Defined in GHC.Float Methods pi :: Float # exp :: Float -> Float # log :: Float -> Float # sqrt :: Float -> Float # (**) :: Float -> Float -> Float # logBase :: Float -> Float -> Float # sin :: Float -> Float # cos :: Float -> Float # tan :: Float -> Float # asin :: Float -> Float # acos :: Float -> Float # atan :: Float -> Float # sinh :: Float -> Float # cosh :: Float -> Float # tanh :: Float -> Float # asinh :: Float -> Float # acosh :: Float -> Float # atanh :: Float -> Float # log1p :: Float -> Float # expm1 :: Float -> Float # log1pexp :: Float -> Float # log1mexp :: Float -> Float #
Ord Float	Note that due to the presence of `NaN`, `Float`'s `Ord` instance does not satisfy reflexivity. `>>>` `0/0 <= (0/0 :: Float)`False Also note that, due to the same, `Ord`'s operator interactions are not respected by `Float`'s instance: `>>>` `(0/0 :: Float) > 1`False `>>>` `compare (0/0 :: Float) 1`GT
Instance details Defined in GHC.Classes Methods compare :: Float -> Float -> Ordering # (<) :: Float -> Float -> Bool # (<=) :: Float -> Float -> Bool # (>) :: Float -> Float -> Bool # (>=) :: Float -> Float -> Bool # max :: Float -> Float -> Float # min :: Float -> Float -> Float #
Read Float	Since: base-2.1
Instance details Defined in GHC.Read Methods readsPrec :: Int -> ReadS Float # readList :: ReadS [Float] # readPrec :: ReadPrec Float # readListPrec :: ReadPrec [Float] #
RealFloat Float	Since: base-2.1
Instance details Defined in GHC.Float Methods floatRadix :: Float -> Integer # floatDigits :: Float -> Int # floatRange :: Float -> (Int, Int) # decodeFloat :: Float -> (Integer, Int) # encodeFloat :: Integer -> Int -> Float # exponent :: Float -> Int # significand :: Float -> Float # scaleFloat :: Int -> Float -> Float # isNaN :: Float -> Bool # isInfinite :: Float -> Bool # isDenormalized :: Float -> Bool # isNegativeZero :: Float -> Bool # isIEEE :: Float -> Bool # atan2 :: Float -> Float -> Float #
NFData Float
Instance details Defined in Control.DeepSeq Methods rnf :: Float -> () #
Hashable Float	Note: prior to `hashable-1.3.0.0`, `hash 0.0 /= hash (-0.0)` The `hash` of NaN is not well defined. Since: hashable-1.3.0.0
Instance details Defined in Data.Hashable.Class Methods hashWithSalt :: Int -> Float -> Int # hash :: Float -> Int #
Generic1 (URec Float :: k -> Type)
Instance details Defined in GHC.Generics Associated Types type Rep1 (URec Float) :: k -> Type # Methods from1 :: URec Float a -> Rep1 (URec Float) a # to1 :: Rep1 (URec Float) a -> URec Float a #
Functor (URec Float :: Type -> Type)	Since: base-4.9.0.0
Instance details Defined in GHC.Generics Methods fmap :: (a -> b) -> URec Float a -> URec Float b # (<$) :: a -> URec Float b -> URec Float a #
Foldable (URec Float :: Type -> Type)	Since: base-4.9.0.0
Instance details Defined in Data.Foldable Methods fold :: Monoid m => URec Float m -> m # foldMap :: Monoid m => (a -> m) -> URec Float a -> m # foldr :: (a -> b -> b) -> b -> URec Float a -> b # foldr' :: (a -> b -> b) -> b -> URec Float a -> b # foldl :: (b -> a -> b) -> b -> URec Float a -> b # foldl' :: (b -> a -> b) -> b -> URec Float a -> b # foldr1 :: (a -> a -> a) -> URec Float a -> a # foldl1 :: (a -> a -> a) -> URec Float a -> a # toList :: URec Float a -> [a] # null :: URec Float a -> Bool # length :: URec Float a -> Int # elem :: Eq a => a -> URec Float a -> Bool # maximum :: Ord a => URec Float a -> a # minimum :: Ord a => URec Float a -> a # sum :: Num a => URec Float a -> a # product :: Num a => URec Float a -> a #
Traversable (URec Float :: Type -> Type)	Since: base-4.9.0.0
Instance details Defined in Data.Traversable Methods traverse :: Applicative f => (a -> f b) -> URec Float a -> f (URec Float b) # sequenceA :: Applicative f => URec Float (f a) -> f (URec Float a) # mapM :: Monad m => (a -> m b) -> URec Float a -> m (URec Float b) # sequence :: Monad m => URec Float (m a) -> m (URec Float a) #
Eq (URec Float p)
Instance details Defined in GHC.Generics Methods (==) :: URec Float p -> URec Float p -> Bool # (/=) :: URec Float p -> URec Float p -> Bool #
Ord (URec Float p)
Instance details Defined in GHC.Generics Methods compare :: URec Float p -> URec Float p -> Ordering # (<) :: URec Float p -> URec Float p -> Bool # (<=) :: URec Float p -> URec Float p -> Bool # (>) :: URec Float p -> URec Float p -> Bool # (>=) :: URec Float p -> URec Float p -> Bool # max :: URec Float p -> URec Float p -> URec Float p # min :: URec Float p -> URec Float p -> URec Float p #
Show (URec Float p)
Instance details Defined in GHC.Generics Methods showsPrec :: Int -> URec Float p -> ShowS # show :: URec Float p -> String # showList :: [URec Float p] -> ShowS #
Generic (URec Float p)
Instance details Defined in GHC.Generics Associated Types type Rep (URec Float p) :: Type -> Type # Methods from :: URec Float p -> Rep (URec Float p) x # to :: Rep (URec Float p) x -> URec Float p #
data URec Float (p :: k)	Used for marking occurrences of `Float#` Since: base-4.9.0.0
Instance details Defined in GHC.Generics data URec Float (p :: k) = UFloat { uFloat# :: Float# }
type Rep1 (URec Float :: k -> Type)	Since: base-4.9.0.0
Instance details Defined in GHC.Generics type Rep1 (URec Float :: k -> Type) = D1 (MetaData "URec" "GHC.Generics" "base" False) (C1 (MetaCons "UFloat" PrefixI True) (S1 (MetaSel (Just "uFloat#") NoSourceUnpackedness NoSourceStrictness DecidedLazy) (UFloat :: k -> Type)))
type Rep (URec Float p)
Instance details Defined in GHC.Generics type Rep (URec Float p) = D1 (MetaData "URec" "GHC.Generics" "base" False) (C1 (MetaCons "UFloat" PrefixI True) (S1 (MetaSel (Just "uFloat#") NoSourceUnpackedness NoSourceStrictness DecidedLazy) (UFloat :: Type -> Type)))

data Int #

A fixed-precision integer type with at least the range [-2^29 .. 2^29-1]. The exact range for a given implementation can be determined by using minBound and maxBound from the Bounded class.

Instances

Bounded Int	Since: base-2.1
Instance details Defined in GHC.Enum Methods minBound :: Int # maxBound :: Int #
Enum Int	Since: base-2.1
Instance details Defined in GHC.Enum Methods succ :: Int -> Int # pred :: Int -> Int # toEnum :: Int -> Int # fromEnum :: Int -> Int # enumFrom :: Int -> [Int] # enumFromThen :: Int -> Int -> [Int] # enumFromTo :: Int -> Int -> [Int] # enumFromThenTo :: Int -> Int -> Int -> [Int] #
Eq Int
Instance details Defined in GHC.Classes Methods (==) :: Int -> Int -> Bool # (/=) :: Int -> Int -> Bool #
Integral Int	Since: base-2.0.1
Instance details Defined in GHC.Real Methods quot :: Int -> Int -> Int # rem :: Int -> Int -> Int # div :: Int -> Int -> Int # mod :: Int -> Int -> Int # quotRem :: Int -> Int -> (Int, Int) # divMod :: Int -> Int -> (Int, Int) # toInteger :: Int -> Integer #
Num Int	Since: base-2.1
Instance details Defined in GHC.Num Methods (+) :: Int -> Int -> Int # (-) :: Int -> Int -> Int # (*) :: Int -> Int -> Int # negate :: Int -> Int # abs :: Int -> Int # signum :: Int -> Int # fromInteger :: Integer -> Int #
Ord Int
Instance details Defined in GHC.Classes Methods compare :: Int -> Int -> Ordering # (<) :: Int -> Int -> Bool # (<=) :: Int -> Int -> Bool # (>) :: Int -> Int -> Bool # (>=) :: Int -> Int -> Bool # max :: Int -> Int -> Int # min :: Int -> Int -> Int #
Read Int	Since: base-2.1
Instance details Defined in GHC.Read Methods readsPrec :: Int -> ReadS Int # readList :: ReadS [Int] # readPrec :: ReadPrec Int # readListPrec :: ReadPrec [Int] #
Real Int	Since: base-2.0.1
Instance details Defined in GHC.Real Methods toRational :: Int -> Rational #
Show Int	Since: base-2.1
Instance details Defined in GHC.Show Methods showsPrec :: Int -> Int -> ShowS # show :: Int -> String # showList :: [Int] -> ShowS #
Bits Int	Since: base-2.1
Instance details Defined in Data.Bits Methods (.&.) :: Int -> Int -> Int # (.\|.) :: Int -> Int -> Int # xor :: Int -> Int -> Int # complement :: Int -> Int # shift :: Int -> Int -> Int # rotate :: Int -> Int -> Int # zeroBits :: Int # bit :: Int -> Int # setBit :: Int -> Int -> Int # clearBit :: Int -> Int -> Int # complementBit :: Int -> Int -> Int # testBit :: Int -> Int -> Bool # bitSizeMaybe :: Int -> Maybe Int # bitSize :: Int -> Int # isSigned :: Int -> Bool # shiftL :: Int -> Int -> Int # unsafeShiftL :: Int -> Int -> Int # shiftR :: Int -> Int -> Int # unsafeShiftR :: Int -> Int -> Int # rotateL :: Int -> Int -> Int # rotateR :: Int -> Int -> Int # popCount :: Int -> Int #
FiniteBits Int	Since: base-4.6.0.0
Instance details Defined in Data.Bits Methods finiteBitSize :: Int -> Int # countLeadingZeros :: Int -> Int # countTrailingZeros :: Int -> Int #
NFData Int
Instance details Defined in Control.DeepSeq Methods rnf :: Int -> () #
Hashable Int
Instance details Defined in Data.Hashable.Class Methods hashWithSalt :: Int -> Int -> Int # hash :: Int -> Int #
Generic1 (URec Int :: k -> Type)
Instance details Defined in GHC.Generics Associated Types type Rep1 (URec Int) :: k -> Type # Methods from1 :: URec Int a -> Rep1 (URec Int) a # to1 :: Rep1 (URec Int) a -> URec Int a #
Functor (URec Int :: Type -> Type)	Since: base-4.9.0.0
Instance details Defined in GHC.Generics Methods fmap :: (a -> b) -> URec Int a -> URec Int b # (<$) :: a -> URec Int b -> URec Int a #
Foldable (URec Int :: Type -> Type)	Since: base-4.9.0.0
Instance details Defined in Data.Foldable Methods fold :: Monoid m => URec Int m -> m # foldMap :: Monoid m => (a -> m) -> URec Int a -> m # foldr :: (a -> b -> b) -> b -> URec Int a -> b # foldr' :: (a -> b -> b) -> b -> URec Int a -> b # foldl :: (b -> a -> b) -> b -> URec Int a -> b # foldl' :: (b -> a -> b) -> b -> URec Int a -> b # foldr1 :: (a -> a -> a) -> URec Int a -> a # foldl1 :: (a -> a -> a) -> URec Int a -> a # toList :: URec Int a -> [a] # null :: URec Int a -> Bool # length :: URec Int a -> Int # elem :: Eq a => a -> URec Int a -> Bool # maximum :: Ord a => URec Int a -> a # minimum :: Ord a => URec Int a -> a # sum :: Num a => URec Int a -> a # product :: Num a => URec Int a -> a #
Traversable (URec Int :: Type -> Type)	Since: base-4.9.0.0
Instance details Defined in Data.Traversable Methods traverse :: Applicative f => (a -> f b) -> URec Int a -> f (URec Int b) # sequenceA :: Applicative f => URec Int (f a) -> f (URec Int a) # mapM :: Monad m => (a -> m b) -> URec Int a -> m (URec Int b) # sequence :: Monad m => URec Int (m a) -> m (URec Int a) #
Eq (URec Int p)	Since: base-4.9.0.0
Instance details Defined in GHC.Generics Methods (==) :: URec Int p -> URec Int p -> Bool # (/=) :: URec Int p -> URec Int p -> Bool #
Ord (URec Int p)	Since: base-4.9.0.0
Instance details Defined in GHC.Generics Methods compare :: URec Int p -> URec Int p -> Ordering # (<) :: URec Int p -> URec Int p -> Bool # (<=) :: URec Int p -> URec Int p -> Bool # (>) :: URec Int p -> URec Int p -> Bool # (>=) :: URec Int p -> URec Int p -> Bool # max :: URec Int p -> URec Int p -> URec Int p # min :: URec Int p -> URec Int p -> URec Int p #
Show (URec Int p)	Since: base-4.9.0.0
Instance details Defined in GHC.Generics Methods showsPrec :: Int -> URec Int p -> ShowS # show :: URec Int p -> String # showList :: [URec Int p] -> ShowS #
Generic (URec Int p)
Instance details Defined in GHC.Generics Associated Types type Rep (URec Int p) :: Type -> Type # Methods from :: URec Int p -> Rep (URec Int p) x # to :: Rep (URec Int p) x -> URec Int p #
data URec Int (p :: k)	Used for marking occurrences of `Int#` Since: base-4.9.0.0
Instance details Defined in GHC.Generics data URec Int (p :: k) = UInt { uInt# :: Int# }
type Rep1 (URec Int :: k -> Type)	Since: base-4.9.0.0
Instance details Defined in GHC.Generics type Rep1 (URec Int :: k -> Type) = D1 (MetaData "URec" "GHC.Generics" "base" False) (C1 (MetaCons "UInt" PrefixI True) (S1 (MetaSel (Just "uInt#") NoSourceUnpackedness NoSourceStrictness DecidedLazy) (UInt :: k -> Type)))
type Rep (URec Int p)	Since: base-4.9.0.0
Instance details Defined in GHC.Generics type Rep (URec Int p) = D1 (MetaData "URec" "GHC.Generics" "base" False) (C1 (MetaCons "UInt" PrefixI True) (S1 (MetaSel (Just "uInt#") NoSourceUnpackedness NoSourceStrictness DecidedLazy) (UInt :: Type -> Type)))

data Int8 #

8-bit signed integer type

Instances

Bounded Int8	Since: base-2.1
Instance details Defined in GHC.Int Methods minBound :: Int8 # maxBound :: Int8 #
Enum Int8	Since: base-2.1
Instance details Defined in GHC.Int Methods succ :: Int8 -> Int8 # pred :: Int8 -> Int8 # toEnum :: Int -> Int8 # fromEnum :: Int8 -> Int # enumFrom :: Int8 -> [Int8] # enumFromThen :: Int8 -> Int8 -> [Int8] # enumFromTo :: Int8 -> Int8 -> [Int8] # enumFromThenTo :: Int8 -> Int8 -> Int8 -> [Int8] #
Eq Int8	Since: base-2.1
Instance details Defined in GHC.Int Methods (==) :: Int8 -> Int8 -> Bool # (/=) :: Int8 -> Int8 -> Bool #
Integral Int8	Since: base-2.1
Instance details Defined in GHC.Int Methods quot :: Int8 -> Int8 -> Int8 # rem :: Int8 -> Int8 -> Int8 # div :: Int8 -> Int8 -> Int8 # mod :: Int8 -> Int8 -> Int8 # quotRem :: Int8 -> Int8 -> (Int8, Int8) # divMod :: Int8 -> Int8 -> (Int8, Int8) # toInteger :: Int8 -> Integer #
Num Int8	Since: base-2.1
Instance details Defined in GHC.Int Methods (+) :: Int8 -> Int8 -> Int8 # (-) :: Int8 -> Int8 -> Int8 # (*) :: Int8 -> Int8 -> Int8 # negate :: Int8 -> Int8 # abs :: Int8 -> Int8 # signum :: Int8 -> Int8 # fromInteger :: Integer -> Int8 #
Ord Int8	Since: base-2.1
Instance details Defined in GHC.Int Methods compare :: Int8 -> Int8 -> Ordering # (<) :: Int8 -> Int8 -> Bool # (<=) :: Int8 -> Int8 -> Bool # (>) :: Int8 -> Int8 -> Bool # (>=) :: Int8 -> Int8 -> Bool # max :: Int8 -> Int8 -> Int8 # min :: Int8 -> Int8 -> Int8 #
Read Int8	Since: base-2.1
Instance details Defined in GHC.Int Methods readsPrec :: Int -> ReadS Int8 # readList :: ReadS [Int8] # readPrec :: ReadPrec Int8 # readListPrec :: ReadPrec [Int8] #
Real Int8	Since: base-2.1
Instance details Defined in GHC.Int Methods toRational :: Int8 -> Rational #
Show Int8	Since: base-2.1
Instance details Defined in GHC.Int Methods showsPrec :: Int -> Int8 -> ShowS # show :: Int8 -> String # showList :: [Int8] -> ShowS #
Ix Int8	Since: base-2.1
Instance details Defined in GHC.Int Methods range :: (Int8, Int8) -> [Int8] # index :: (Int8, Int8) -> Int8 -> Int # unsafeIndex :: (Int8, Int8) -> Int8 -> Int inRange :: (Int8, Int8) -> Int8 -> Bool # rangeSize :: (Int8, Int8) -> Int # unsafeRangeSize :: (Int8, Int8) -> Int
Bits Int8	Since: base-2.1
Instance details Defined in GHC.Int Methods (.&.) :: Int8 -> Int8 -> Int8 # (.\|.) :: Int8 -> Int8 -> Int8 # xor :: Int8 -> Int8 -> Int8 # complement :: Int8 -> Int8 # shift :: Int8 -> Int -> Int8 # rotate :: Int8 -> Int -> Int8 # zeroBits :: Int8 # bit :: Int -> Int8 # setBit :: Int8 -> Int -> Int8 # clearBit :: Int8 -> Int -> Int8 # complementBit :: Int8 -> Int -> Int8 # testBit :: Int8 -> Int -> Bool # bitSizeMaybe :: Int8 -> Maybe Int # bitSize :: Int8 -> Int # isSigned :: Int8 -> Bool # shiftL :: Int8 -> Int -> Int8 # unsafeShiftL :: Int8 -> Int -> Int8 # shiftR :: Int8 -> Int -> Int8 # unsafeShiftR :: Int8 -> Int -> Int8 # rotateL :: Int8 -> Int -> Int8 # rotateR :: Int8 -> Int -> Int8 # popCount :: Int8 -> Int #
FiniteBits Int8	Since: base-4.6.0.0
Instance details Defined in GHC.Int Methods finiteBitSize :: Int8 -> Int # countLeadingZeros :: Int8 -> Int # countTrailingZeros :: Int8 -> Int #
NFData Int8
Instance details Defined in Control.DeepSeq Methods rnf :: Int8 -> () #
Hashable Int8
Instance details Defined in Data.Hashable.Class Methods hashWithSalt :: Int -> Int8 -> Int # hash :: Int8 -> Int #

data Int16 #

16-bit signed integer type

Instances

Bounded Int16	Since: base-2.1
Instance details Defined in GHC.Int Methods minBound :: Int16 # maxBound :: Int16 #
Enum Int16	Since: base-2.1
Instance details Defined in GHC.Int Methods succ :: Int16 -> Int16 # pred :: Int16 -> Int16 # toEnum :: Int -> Int16 # fromEnum :: Int16 -> Int # enumFrom :: Int16 -> [Int16] # enumFromThen :: Int16 -> Int16 -> [Int16] # enumFromTo :: Int16 -> Int16 -> [Int16] # enumFromThenTo :: Int16 -> Int16 -> Int16 -> [Int16] #
Eq Int16	Since: base-2.1
Instance details Defined in GHC.Int Methods (==) :: Int16 -> Int16 -> Bool # (/=) :: Int16 -> Int16 -> Bool #
Integral Int16	Since: base-2.1
Instance details Defined in GHC.Int Methods quot :: Int16 -> Int16 -> Int16 # rem :: Int16 -> Int16 -> Int16 # div :: Int16 -> Int16 -> Int16 # mod :: Int16 -> Int16 -> Int16 # quotRem :: Int16 -> Int16 -> (Int16, Int16) # divMod :: Int16 -> Int16 -> (Int16, Int16) # toInteger :: Int16 -> Integer #
Num Int16	Since: base-2.1
Instance details Defined in GHC.Int Methods (+) :: Int16 -> Int16 -> Int16 # (-) :: Int16 -> Int16 -> Int16 # (*) :: Int16 -> Int16 -> Int16 # negate :: Int16 -> Int16 # abs :: Int16 -> Int16 # signum :: Int16 -> Int16 # fromInteger :: Integer -> Int16 #
Ord Int16	Since: base-2.1
Instance details Defined in GHC.Int Methods compare :: Int16 -> Int16 -> Ordering # (<) :: Int16 -> Int16 -> Bool # (<=) :: Int16 -> Int16 -> Bool # (>) :: Int16 -> Int16 -> Bool # (>=) :: Int16 -> Int16 -> Bool # max :: Int16 -> Int16 -> Int16 # min :: Int16 -> Int16 -> Int16 #
Read Int16	Since: base-2.1
Instance details Defined in GHC.Int Methods readsPrec :: Int -> ReadS Int16 # readList :: ReadS [Int16] # readPrec :: ReadPrec Int16 # readListPrec :: ReadPrec [Int16] #
Real Int16	Since: base-2.1
Instance details Defined in GHC.Int Methods toRational :: Int16 -> Rational #
Show Int16	Since: base-2.1
Instance details Defined in GHC.Int Methods showsPrec :: Int -> Int16 -> ShowS # show :: Int16 -> String # showList :: [Int16] -> ShowS #
Ix Int16	Since: base-2.1
Instance details Defined in GHC.Int Methods range :: (Int16, Int16) -> [Int16] # index :: (Int16, Int16) -> Int16 -> Int # unsafeIndex :: (Int16, Int16) -> Int16 -> Int inRange :: (Int16, Int16) -> Int16 -> Bool # rangeSize :: (Int16, Int16) -> Int # unsafeRangeSize :: (Int16, Int16) -> Int
Bits Int16	Since: base-2.1
Instance details Defined in GHC.Int Methods (.&.) :: Int16 -> Int16 -> Int16 # (.\|.) :: Int16 -> Int16 -> Int16 # xor :: Int16 -> Int16 -> Int16 # complement :: Int16 -> Int16 # shift :: Int16 -> Int -> Int16 # rotate :: Int16 -> Int -> Int16 # zeroBits :: Int16 # bit :: Int -> Int16 # setBit :: Int16 -> Int -> Int16 # clearBit :: Int16 -> Int -> Int16 # complementBit :: Int16 -> Int -> Int16 # testBit :: Int16 -> Int -> Bool # bitSizeMaybe :: Int16 -> Maybe Int # bitSize :: Int16 -> Int # isSigned :: Int16 -> Bool # shiftL :: Int16 -> Int -> Int16 # unsafeShiftL :: Int16 -> Int -> Int16 # shiftR :: Int16 -> Int -> Int16 # unsafeShiftR :: Int16 -> Int -> Int16 # rotateL :: Int16 -> Int -> Int16 # rotateR :: Int16 -> Int -> Int16 # popCount :: Int16 -> Int #
FiniteBits Int16	Since: base-4.6.0.0
Instance details Defined in GHC.Int Methods finiteBitSize :: Int16 -> Int # countLeadingZeros :: Int16 -> Int # countTrailingZeros :: Int16 -> Int #
NFData Int16
Instance details Defined in Control.DeepSeq Methods rnf :: Int16 -> () #
Hashable Int16
Instance details Defined in Data.Hashable.Class Methods hashWithSalt :: Int -> Int16 -> Int # hash :: Int16 -> Int #

data Int32 #

32-bit signed integer type

Instances

Bounded Int32	Since: base-2.1
Instance details Defined in GHC.Int Methods minBound :: Int32 # maxBound :: Int32 #
Enum Int32	Since: base-2.1
Instance details Defined in GHC.Int Methods succ :: Int32 -> Int32 # pred :: Int32 -> Int32 # toEnum :: Int -> Int32 # fromEnum :: Int32 -> Int # enumFrom :: Int32 -> [Int32] # enumFromThen :: Int32 -> Int32 -> [Int32] # enumFromTo :: Int32 -> Int32 -> [Int32] # enumFromThenTo :: Int32 -> Int32 -> Int32 -> [Int32] #
Eq Int32	Since: base-2.1
Instance details Defined in GHC.Int Methods (==) :: Int32 -> Int32 -> Bool # (/=) :: Int32 -> Int32 -> Bool #
Integral Int32	Since: base-2.1
Instance details Defined in GHC.Int Methods quot :: Int32 -> Int32 -> Int32 # rem :: Int32 -> Int32 -> Int32 # div :: Int32 -> Int32 -> Int32 # mod :: Int32 -> Int32 -> Int32 # quotRem :: Int32 -> Int32 -> (Int32, Int32) # divMod :: Int32 -> Int32 -> (Int32, Int32) # toInteger :: Int32 -> Integer #
Num Int32	Since: base-2.1
Instance details Defined in GHC.Int Methods (+) :: Int32 -> Int32 -> Int32 # (-) :: Int32 -> Int32 -> Int32 # (*) :: Int32 -> Int32 -> Int32 # negate :: Int32 -> Int32 # abs :: Int32 -> Int32 # signum :: Int32 -> Int32 # fromInteger :: Integer -> Int32 #
Ord Int32	Since: base-2.1
Instance details Defined in GHC.Int Methods compare :: Int32 -> Int32 -> Ordering # (<) :: Int32 -> Int32 -> Bool # (<=) :: Int32 -> Int32 -> Bool # (>) :: Int32 -> Int32 -> Bool # (>=) :: Int32 -> Int32 -> Bool # max :: Int32 -> Int32 -> Int32 # min :: Int32 -> Int32 -> Int32 #
Read Int32	Since: base-2.1
Instance details Defined in GHC.Int Methods readsPrec :: Int -> ReadS Int32 # readList :: ReadS [Int32] # readPrec :: ReadPrec Int32 # readListPrec :: ReadPrec [Int32] #
Real Int32	Since: base-2.1
Instance details Defined in GHC.Int Methods toRational :: Int32 -> Rational #
Show Int32	Since: base-2.1
Instance details Defined in GHC.Int Methods showsPrec :: Int -> Int32 -> ShowS # show :: Int32 -> String # showList :: [Int32] -> ShowS #
Ix Int32	Since: base-2.1
Instance details Defined in GHC.Int Methods range :: (Int32, Int32) -> [Int32] # index :: (Int32, Int32) -> Int32 -> Int # unsafeIndex :: (Int32, Int32) -> Int32 -> Int inRange :: (Int32, Int32) -> Int32 -> Bool # rangeSize :: (Int32, Int32) -> Int # unsafeRangeSize :: (Int32, Int32) -> Int
Bits Int32	Since: base-2.1
Instance details Defined in GHC.Int Methods (.&.) :: Int32 -> Int32 -> Int32 # (.\|.) :: Int32 -> Int32 -> Int32 # xor :: Int32 -> Int32 -> Int32 # complement :: Int32 -> Int32 # shift :: Int32 -> Int -> Int32 # rotate :: Int32 -> Int -> Int32 # zeroBits :: Int32 # bit :: Int -> Int32 # setBit :: Int32 -> Int -> Int32 # clearBit :: Int32 -> Int -> Int32 # complementBit :: Int32 -> Int -> Int32 # testBit :: Int32 -> Int -> Bool # bitSizeMaybe :: Int32 -> Maybe Int # bitSize :: Int32 -> Int # isSigned :: Int32 -> Bool # shiftL :: Int32 -> Int -> Int32 # unsafeShiftL :: Int32 -> Int -> Int32 # shiftR :: Int32 -> Int -> Int32 # unsafeShiftR :: Int32 -> Int -> Int32 # rotateL :: Int32 -> Int -> Int32 # rotateR :: Int32 -> Int -> Int32 # popCount :: Int32 -> Int #
FiniteBits Int32	Since: base-4.6.0.0
Instance details Defined in GHC.Int Methods finiteBitSize :: Int32 -> Int # countLeadingZeros :: Int32 -> Int # countTrailingZeros :: Int32 -> Int #
NFData Int32
Instance details Defined in Control.DeepSeq Methods rnf :: Int32 -> () #
Hashable Int32
Instance details Defined in Data.Hashable.Class Methods hashWithSalt :: Int -> Int32 -> Int # hash :: Int32 -> Int #

data Int64 #

64-bit signed integer type

Instances

Bounded Int64	Since: base-2.1
Instance details Defined in GHC.Int Methods minBound :: Int64 # maxBound :: Int64 #
Enum Int64	Since: base-2.1
Instance details Defined in GHC.Int Methods succ :: Int64 -> Int64 # pred :: Int64 -> Int64 # toEnum :: Int -> Int64 # fromEnum :: Int64 -> Int # enumFrom :: Int64 -> [Int64] # enumFromThen :: Int64 -> Int64 -> [Int64] # enumFromTo :: Int64 -> Int64 -> [Int64] # enumFromThenTo :: Int64 -> Int64 -> Int64 -> [Int64] #
Eq Int64	Since: base-2.1
Instance details Defined in GHC.Int Methods (==) :: Int64 -> Int64 -> Bool # (/=) :: Int64 -> Int64 -> Bool #
Integral Int64	Since: base-2.1
Instance details Defined in GHC.Int Methods quot :: Int64 -> Int64 -> Int64 # rem :: Int64 -> Int64 -> Int64 # div :: Int64 -> Int64 -> Int64 # mod :: Int64 -> Int64 -> Int64 # quotRem :: Int64 -> Int64 -> (Int64, Int64) # divMod :: Int64 -> Int64 -> (Int64, Int64) # toInteger :: Int64 -> Integer #
Num Int64	Since: base-2.1
Instance details Defined in GHC.Int Methods (+) :: Int64 -> Int64 -> Int64 # (-) :: Int64 -> Int64 -> Int64 # (*) :: Int64 -> Int64 -> Int64 # negate :: Int64 -> Int64 # abs :: Int64 -> Int64 # signum :: Int64 -> Int64 # fromInteger :: Integer -> Int64 #
Ord Int64	Since: base-2.1
Instance details Defined in GHC.Int Methods compare :: Int64 -> Int64 -> Ordering # (<) :: Int64 -> Int64 -> Bool # (<=) :: Int64 -> Int64 -> Bool # (>) :: Int64 -> Int64 -> Bool # (>=) :: Int64 -> Int64 -> Bool # max :: Int64 -> Int64 -> Int64 # min :: Int64 -> Int64 -> Int64 #
Read Int64	Since: base-2.1
Instance details Defined in GHC.Int Methods readsPrec :: Int -> ReadS Int64 # readList :: ReadS [Int64] # readPrec :: ReadPrec Int64 # readListPrec :: ReadPrec [Int64] #
Real Int64	Since: base-2.1
Instance details Defined in GHC.Int Methods toRational :: Int64 -> Rational #
Show Int64	Since: base-2.1
Instance details Defined in GHC.Int Methods showsPrec :: Int -> Int64 -> ShowS # show :: Int64 -> String # showList :: [Int64] -> ShowS #
Ix Int64	Since: base-2.1
Instance details Defined in GHC.Int Methods range :: (Int64, Int64) -> [Int64] # index :: (Int64, Int64) -> Int64 -> Int # unsafeIndex :: (Int64, Int64) -> Int64 -> Int inRange :: (Int64, Int64) -> Int64 -> Bool # rangeSize :: (Int64, Int64) -> Int # unsafeRangeSize :: (Int64, Int64) -> Int
Bits Int64	Since: base-2.1
Instance details Defined in GHC.Int Methods (.&.) :: Int64 -> Int64 -> Int64 # (.\|.) :: Int64 -> Int64 -> Int64 # xor :: Int64 -> Int64 -> Int64 # complement :: Int64 -> Int64 # shift :: Int64 -> Int -> Int64 # rotate :: Int64 -> Int -> Int64 # zeroBits :: Int64 # bit :: Int -> Int64 # setBit :: Int64 -> Int -> Int64 # clearBit :: Int64 -> Int -> Int64 # complementBit :: Int64 -> Int -> Int64 # testBit :: Int64 -> Int -> Bool # bitSizeMaybe :: Int64 -> Maybe Int # bitSize :: Int64 -> Int # isSigned :: Int64 -> Bool # shiftL :: Int64 -> Int -> Int64 # unsafeShiftL :: Int64 -> Int -> Int64 # shiftR :: Int64 -> Int -> Int64 # unsafeShiftR :: Int64 -> Int -> Int64 # rotateL :: Int64 -> Int -> Int64 # rotateR :: Int64 -> Int -> Int64 # popCount :: Int64 -> Int #
FiniteBits Int64	Since: base-4.6.0.0
Instance details Defined in GHC.Int Methods finiteBitSize :: Int64 -> Int # countLeadingZeros :: Int64 -> Int # countTrailingZeros :: Int64 -> Int #
NFData Int64
Instance details Defined in Control.DeepSeq Methods rnf :: Int64 -> () #
Hashable Int64
Instance details Defined in Data.Hashable.Class Methods hashWithSalt :: Int -> Int64 -> Int # hash :: Int64 -> Int #

data Integer #

Invariant: Jn# and Jp# are used iff value doesn't fit in S#

Useful properties resulting from the invariants:

```
abs (S# _) <= abs (Jp# _)
```
```
abs (S# _) <  abs (Jn# _)
```

Instances

Enum Integer	Since: base-2.1
Instance details Defined in GHC.Enum Methods succ :: Integer -> Integer # pred :: Integer -> Integer # toEnum :: Int -> Integer # fromEnum :: Integer -> Int # enumFrom :: Integer -> [Integer] # enumFromThen :: Integer -> Integer -> [Integer] # enumFromTo :: Integer -> Integer -> [Integer] # enumFromThenTo :: Integer -> Integer -> Integer -> [Integer] #
Eq Integer
Instance details Defined in GHC.Integer.Type Methods (==) :: Integer -> Integer -> Bool # (/=) :: Integer -> Integer -> Bool #
Integral Integer	Since: base-2.0.1
Instance details Defined in GHC.Real Methods quot :: Integer -> Integer -> Integer # rem :: Integer -> Integer -> Integer # div :: Integer -> Integer -> Integer # mod :: Integer -> Integer -> Integer # quotRem :: Integer -> Integer -> (Integer, Integer) # divMod :: Integer -> Integer -> (Integer, Integer) # toInteger :: Integer -> Integer #
Num Integer	Since: base-2.1
Instance details Defined in GHC.Num Methods (+) :: Integer -> Integer -> Integer # (-) :: Integer -> Integer -> Integer # (*) :: Integer -> Integer -> Integer # negate :: Integer -> Integer # abs :: Integer -> Integer # signum :: Integer -> Integer # fromInteger :: Integer -> Integer #
Ord Integer
Instance details Defined in GHC.Integer.Type Methods compare :: Integer -> Integer -> Ordering # (<) :: Integer -> Integer -> Bool # (<=) :: Integer -> Integer -> Bool # (>) :: Integer -> Integer -> Bool # (>=) :: Integer -> Integer -> Bool # max :: Integer -> Integer -> Integer # min :: Integer -> Integer -> Integer #
Read Integer	Since: base-2.1
Instance details Defined in GHC.Read Methods readsPrec :: Int -> ReadS Integer # readList :: ReadS [Integer] # readPrec :: ReadPrec Integer # readListPrec :: ReadPrec [Integer] #
Real Integer	Since: base-2.0.1
Instance details Defined in GHC.Real Methods toRational :: Integer -> Rational #
Show Integer	Since: base-2.1
Instance details Defined in GHC.Show Methods showsPrec :: Int -> Integer -> ShowS # show :: Integer -> String # showList :: [Integer] -> ShowS #
Bits Integer	Since: base-2.1
Instance details Defined in Data.Bits Methods (.&.) :: Integer -> Integer -> Integer # (.\|.) :: Integer -> Integer -> Integer # xor :: Integer -> Integer -> Integer # complement :: Integer -> Integer # shift :: Integer -> Int -> Integer # rotate :: Integer -> Int -> Integer # zeroBits :: Integer # bit :: Int -> Integer # setBit :: Integer -> Int -> Integer # clearBit :: Integer -> Int -> Integer # complementBit :: Integer -> Int -> Integer # testBit :: Integer -> Int -> Bool # bitSizeMaybe :: Integer -> Maybe Int # bitSize :: Integer -> Int # isSigned :: Integer -> Bool # shiftL :: Integer -> Int -> Integer # unsafeShiftL :: Integer -> Int -> Integer # shiftR :: Integer -> Int -> Integer # unsafeShiftR :: Integer -> Int -> Integer # rotateL :: Integer -> Int -> Integer # rotateR :: Integer -> Int -> Integer # popCount :: Integer -> Int #
NFData Integer
Instance details Defined in Control.DeepSeq Methods rnf :: Integer -> () #
Hashable Integer
Instance details Defined in Data.Hashable.Class Methods hashWithSalt :: Int -> Integer -> Int # hash :: Integer -> Int #

data Natural #

Type representing arbitrary-precision non-negative integers.

>>> 2^100 :: Natural
1267650600228229401496703205376

Operations whose result would be negative throw (Underflow :: ArithException),

>>> -1 :: Natural
*** Exception: arithmetic underflow

Since: base-4.8.0.0

Instances

Enum Natural	Since: base-4.8.0.0
Instance details Defined in GHC.Enum Methods succ :: Natural -> Natural # pred :: Natural -> Natural # toEnum :: Int -> Natural # fromEnum :: Natural -> Int # enumFrom :: Natural -> [Natural] # enumFromThen :: Natural -> Natural -> [Natural] # enumFromTo :: Natural -> Natural -> [Natural] # enumFromThenTo :: Natural -> Natural -> Natural -> [Natural] #
Eq Natural	Since: base-4.8.0.0
Instance details Defined in GHC.Natural Methods (==) :: Natural -> Natural -> Bool # (/=) :: Natural -> Natural -> Bool #
Integral Natural	Since: base-4.8.0.0
Instance details Defined in GHC.Real Methods quot :: Natural -> Natural -> Natural # rem :: Natural -> Natural -> Natural # div :: Natural -> Natural -> Natural # mod :: Natural -> Natural -> Natural # quotRem :: Natural -> Natural -> (Natural, Natural) # divMod :: Natural -> Natural -> (Natural, Natural) # toInteger :: Natural -> Integer #
Num Natural	Note that `Natural`'s `Num` instance isn't a ring: no element but 0 has an additive inverse. It is a semiring though. Since: base-4.8.0.0
Instance details Defined in GHC.Num Methods (+) :: Natural -> Natural -> Natural # (-) :: Natural -> Natural -> Natural # (*) :: Natural -> Natural -> Natural # negate :: Natural -> Natural # abs :: Natural -> Natural # signum :: Natural -> Natural # fromInteger :: Integer -> Natural #
Ord Natural	Since: base-4.8.0.0
Instance details Defined in GHC.Natural Methods compare :: Natural -> Natural -> Ordering # (<) :: Natural -> Natural -> Bool # (<=) :: Natural -> Natural -> Bool # (>) :: Natural -> Natural -> Bool # (>=) :: Natural -> Natural -> Bool # max :: Natural -> Natural -> Natural # min :: Natural -> Natural -> Natural #
Read Natural	Since: base-4.8.0.0
Instance details Defined in GHC.Read Methods readsPrec :: Int -> ReadS Natural # readList :: ReadS [Natural] # readPrec :: ReadPrec Natural # readListPrec :: ReadPrec [Natural] #
Real Natural	Since: base-4.8.0.0
Instance details Defined in GHC.Real Methods toRational :: Natural -> Rational #
Show Natural	Since: base-4.8.0.0
Instance details Defined in GHC.Show Methods showsPrec :: Int -> Natural -> ShowS # show :: Natural -> String # showList :: [Natural] -> ShowS #
Bits Natural	Since: base-4.8.0
Instance details Defined in Data.Bits Methods (.&.) :: Natural -> Natural -> Natural # (.\|.) :: Natural -> Natural -> Natural # xor :: Natural -> Natural -> Natural # complement :: Natural -> Natural # shift :: Natural -> Int -> Natural # rotate :: Natural -> Int -> Natural # zeroBits :: Natural # bit :: Int -> Natural # setBit :: Natural -> Int -> Natural # clearBit :: Natural -> Int -> Natural # complementBit :: Natural -> Int -> Natural # testBit :: Natural -> Int -> Bool # bitSizeMaybe :: Natural -> Maybe Int # bitSize :: Natural -> Int # isSigned :: Natural -> Bool # shiftL :: Natural -> Int -> Natural # unsafeShiftL :: Natural -> Int -> Natural # shiftR :: Natural -> Int -> Natural # unsafeShiftR :: Natural -> Int -> Natural # rotateL :: Natural -> Int -> Natural # rotateR :: Natural -> Int -> Natural # popCount :: Natural -> Int #
NFData Natural	Since: deepseq-1.4.0.0
Instance details Defined in Control.DeepSeq Methods rnf :: Natural -> () #
Hashable Natural
Instance details Defined in Data.Hashable.Class Methods hashWithSalt :: Int -> Natural -> Int # hash :: Natural -> Int #

data Maybe a #

The Maybe type encapsulates an optional value. A value of type Maybe a either contains a value of type a (represented as Just a), or it is empty (represented as Nothing). Using Maybe is a good way to deal with errors or exceptional cases without resorting to drastic measures such as error.

The Maybe type is also a monad. It is a simple kind of error monad, where all errors are represented by Nothing. A richer error monad can be built using the Either type.

Constructors

Nothing
Just a

Instances

Monad Maybe	Since: base-2.1
Instance details Defined in GHC.Base Methods (>>=) :: Maybe a -> (a -> Maybe b) -> Maybe b # (>>) :: Maybe a -> Maybe b -> Maybe b # return :: a -> Maybe a # fail :: String -> Maybe a #
Functor Maybe	Since: base-2.1
Instance details Defined in GHC.Base Methods fmap :: (a -> b) -> Maybe a -> Maybe b # (<$) :: a -> Maybe b -> Maybe a #
MonadFail Maybe	Since: base-4.9.0.0
Instance details Defined in Control.Monad.Fail Methods fail :: String -> Maybe a #
Applicative Maybe	Since: base-2.1
Instance details Defined in GHC.Base Methods pure :: a -> Maybe a # (<>) :: Maybe (a -> b) -> Maybe a -> Maybe b # liftA2 :: (a -> b -> c) -> Maybe a -> Maybe b -> Maybe c # (>) :: Maybe a -> Maybe b -> Maybe b # (<*) :: Maybe a -> Maybe b -> Maybe a #
Foldable Maybe	Since: base-2.1
Instance details Defined in Data.Foldable Methods fold :: Monoid m => Maybe m -> m # foldMap :: Monoid m => (a -> m) -> Maybe a -> m # foldr :: (a -> b -> b) -> b -> Maybe a -> b # foldr' :: (a -> b -> b) -> b -> Maybe a -> b # foldl :: (b -> a -> b) -> b -> Maybe a -> b # foldl' :: (b -> a -> b) -> b -> Maybe a -> b # foldr1 :: (a -> a -> a) -> Maybe a -> a # foldl1 :: (a -> a -> a) -> Maybe a -> a # toList :: Maybe a -> [a] # null :: Maybe a -> Bool # length :: Maybe a -> Int # elem :: Eq a => a -> Maybe a -> Bool # maximum :: Ord a => Maybe a -> a # minimum :: Ord a => Maybe a -> a # sum :: Num a => Maybe a -> a # product :: Num a => Maybe a -> a #
Traversable Maybe	Since: base-2.1
Instance details Defined in Data.Traversable Methods traverse :: Applicative f => (a -> f b) -> Maybe a -> f (Maybe b) # sequenceA :: Applicative f => Maybe (f a) -> f (Maybe a) # mapM :: Monad m => (a -> m b) -> Maybe a -> m (Maybe b) # sequence :: Monad m => Maybe (m a) -> m (Maybe a) #
Alternative Maybe	Since: base-2.1
Instance details Defined in GHC.Base Methods empty :: Maybe a # (<\|>) :: Maybe a -> Maybe a -> Maybe a # some :: Maybe a -> Maybe [a] # many :: Maybe a -> Maybe [a] #
MonadPlus Maybe	Since: base-2.1
Instance details Defined in GHC.Base Methods mzero :: Maybe a # mplus :: Maybe a -> Maybe a -> Maybe a #
NFData1 Maybe	Since: deepseq-1.4.3.0
Instance details Defined in Control.DeepSeq Methods liftRnf :: (a -> ()) -> Maybe a -> () #
MonadThrow Maybe
Instance details Defined in Control.Monad.Catch Methods throwM :: Exception e => e -> Maybe a #
Hashable1 Maybe
Instance details Defined in Data.Hashable.Class Methods liftHashWithSalt :: (Int -> a -> Int) -> Int -> Maybe a -> Int #
MonadError () Maybe	Since: mtl-2.2.2
Instance details Defined in Control.Monad.Error.Class Methods throwError :: () -> Maybe a # catchError :: Maybe a -> (() -> Maybe a) -> Maybe a #
Eq a => Eq (Maybe a)	Since: base-2.1
Instance details Defined in GHC.Maybe Methods (==) :: Maybe a -> Maybe a -> Bool # (/=) :: Maybe a -> Maybe a -> Bool #
Ord a => Ord (Maybe a)	Since: base-2.1
Instance details Defined in GHC.Maybe Methods compare :: Maybe a -> Maybe a -> Ordering # (<) :: Maybe a -> Maybe a -> Bool # (<=) :: Maybe a -> Maybe a -> Bool # (>) :: Maybe a -> Maybe a -> Bool # (>=) :: Maybe a -> Maybe a -> Bool # max :: Maybe a -> Maybe a -> Maybe a # min :: Maybe a -> Maybe a -> Maybe a #
Read a => Read (Maybe a)	Since: base-2.1
Instance details Defined in GHC.Read Methods readsPrec :: Int -> ReadS (Maybe a) # readList :: ReadS [Maybe a] # readPrec :: ReadPrec (Maybe a) # readListPrec :: ReadPrec [Maybe a] #
Show a => Show (Maybe a)	Since: base-2.1
Instance details Defined in GHC.Show Methods showsPrec :: Int -> Maybe a -> ShowS # show :: Maybe a -> String # showList :: [Maybe a] -> ShowS #
Generic (Maybe a)
Instance details Defined in GHC.Generics Associated Types type Rep (Maybe a) :: Type -> Type # Methods from :: Maybe a -> Rep (Maybe a) x # to :: Rep (Maybe a) x -> Maybe a #
Semigroup a => Semigroup (Maybe a)	Since: base-4.9.0.0
Instance details Defined in GHC.Base Methods (<>) :: Maybe a -> Maybe a -> Maybe a # sconcat :: NonEmpty (Maybe a) -> Maybe a # stimes :: Integral b => b -> Maybe a -> Maybe a #
Semigroup a => Monoid (Maybe a)	Lift a semigroup into `Maybe` forming a `Monoid` according to http://en.wikipedia.org/wiki/Monoid: "Any semigroup `S` may be turned into a monoid simply by adjoining an element `e` not in `S` and defining `ee = e` and `es = s = se` for all `s ∈ S`." Since 4.11.0: constraint on inner `a` value generalised from `Monoid` to `Semigroup`. Since: base-2.1*
Instance details Defined in GHC.Base Methods mempty :: Maybe a # mappend :: Maybe a -> Maybe a -> Maybe a # mconcat :: [Maybe a] -> Maybe a #
SingKind a => SingKind (Maybe a)	Since: base-4.9.0.0
Instance details Defined in GHC.Generics Associated Types type DemoteRep (Maybe a) :: Type Methods fromSing :: Sing a0 -> DemoteRep (Maybe a)
NFData a => NFData (Maybe a)
Instance details Defined in Control.DeepSeq Methods rnf :: Maybe a -> () #
Hashable a => Hashable (Maybe a)
Instance details Defined in Data.Hashable.Class Methods hashWithSalt :: Int -> Maybe a -> Int # hash :: Maybe a -> Int #
(TypeError (DisallowInstance "Maybe") :: Constraint) => Container (Maybe a)
Instance details Defined in Universum.Container.Class Associated Types type Element (Maybe a) :: Type # Methods toList :: Maybe a -> [Element (Maybe a)] # null :: Maybe a -> Bool # foldr :: (Element (Maybe a) -> b -> b) -> b -> Maybe a -> b # foldl :: (b -> Element (Maybe a) -> b) -> b -> Maybe a -> b # foldl' :: (b -> Element (Maybe a) -> b) -> b -> Maybe a -> b # length :: Maybe a -> Int # elem :: Element (Maybe a) -> Maybe a -> Bool # maximum :: Maybe a -> Element (Maybe a) # minimum :: Maybe a -> Element (Maybe a) # foldMap :: Monoid m => (Element (Maybe a) -> m) -> Maybe a -> m # fold :: Maybe a -> Element (Maybe a) # foldr' :: (Element (Maybe a) -> b -> b) -> b -> Maybe a -> b # foldr1 :: (Element (Maybe a) -> Element (Maybe a) -> Element (Maybe a)) -> Maybe a -> Element (Maybe a) # foldl1 :: (Element (Maybe a) -> Element (Maybe a) -> Element (Maybe a)) -> Maybe a -> Element (Maybe a) # notElem :: Element (Maybe a) -> Maybe a -> Bool # all :: (Element (Maybe a) -> Bool) -> Maybe a -> Bool # any :: (Element (Maybe a) -> Bool) -> Maybe a -> Bool # and :: Maybe a -> Bool # or :: Maybe a -> Bool # find :: (Element (Maybe a) -> Bool) -> Maybe a -> Maybe (Element (Maybe a)) # safeHead :: Maybe a -> Maybe (Element (Maybe a)) #
Generic1 Maybe
Instance details Defined in GHC.Generics Associated Types type Rep1 Maybe :: k -> Type # Methods from1 :: Maybe a -> Rep1 Maybe a # to1 :: Rep1 Maybe a -> Maybe a #
SingI (Nothing :: Maybe a)	Since: base-4.9.0.0
Instance details Defined in GHC.Generics Methods sing :: Sing Nothing
Each (Maybe a) (Maybe b) a b
Instance details Defined in Lens.Micro.Internal Methods each :: Traversal (Maybe a) (Maybe b) a b #
SingI a2 => SingI (Just a2 :: Maybe a1)	Since: base-4.9.0.0
Instance details Defined in GHC.Generics Methods sing :: Sing (Just a2)
type Rep (Maybe a)	Since: base-4.6.0.0
Instance details Defined in GHC.Generics type Rep (Maybe a) = D1 (MetaData "Maybe" "GHC.Maybe" "base" False) (C1 (MetaCons "Nothing" PrefixI False) (U1 :: Type -> Type) :+: C1 (MetaCons "Just" PrefixI False) (S1 (MetaSel (Nothing :: Maybe Symbol) NoSourceUnpackedness NoSourceStrictness DecidedLazy) (Rec0 a)))
data Sing (b :: Maybe a)
Instance details Defined in GHC.Generics data Sing (b :: Maybe a) where SNothing :: forall a (b :: Maybe a). Sing (Nothing :: Maybe a) SJust :: forall a (b :: Maybe a) (a1 :: a). Sing a1 -> Sing (Just a1)
type DemoteRep (Maybe a)
Instance details Defined in GHC.Generics type DemoteRep (Maybe a) = Maybe (DemoteRep a)
type Element (Maybe a)
Instance details Defined in Universum.Container.Class type Element (Maybe a) = ElementDefault (Maybe a)
type Rep1 Maybe	Since: base-4.6.0.0
Instance details Defined in GHC.Generics type Rep1 Maybe = D1 (MetaData "Maybe" "GHC.Maybe" "base" False) (C1 (MetaCons "Nothing" PrefixI False) (U1 :: Type -> Type) :+: C1 (MetaCons "Just" PrefixI False) (S1 (MetaSel (Nothing :: Maybe Symbol) NoSourceUnpackedness NoSourceStrictness DecidedLazy) Par1))

data Ordering #

Constructors

LT
EQ
GT

Instances

Bounded Ordering	Since: base-2.1
Instance details Defined in GHC.Enum Methods minBound :: Ordering # maxBound :: Ordering #
Enum Ordering	Since: base-2.1
Instance details Defined in GHC.Enum Methods succ :: Ordering -> Ordering # pred :: Ordering -> Ordering # toEnum :: Int -> Ordering # fromEnum :: Ordering -> Int # enumFrom :: Ordering -> [Ordering] # enumFromThen :: Ordering -> Ordering -> [Ordering] # enumFromTo :: Ordering -> Ordering -> [Ordering] # enumFromThenTo :: Ordering -> Ordering -> Ordering -> [Ordering] #
Eq Ordering
Instance details Defined in GHC.Classes Methods (==) :: Ordering -> Ordering -> Bool # (/=) :: Ordering -> Ordering -> Bool #
Ord Ordering
Instance details Defined in GHC.Classes Methods compare :: Ordering -> Ordering -> Ordering # (<) :: Ordering -> Ordering -> Bool # (<=) :: Ordering -> Ordering -> Bool # (>) :: Ordering -> Ordering -> Bool # (>=) :: Ordering -> Ordering -> Bool # max :: Ordering -> Ordering -> Ordering # min :: Ordering -> Ordering -> Ordering #
Read Ordering	Since: base-2.1
Instance details Defined in GHC.Read Methods readsPrec :: Int -> ReadS Ordering # readList :: ReadS [Ordering] # readPrec :: ReadPrec Ordering # readListPrec :: ReadPrec [Ordering] #
Show Ordering	Since: base-2.1
Instance details Defined in GHC.Show Methods showsPrec :: Int -> Ordering -> ShowS # show :: Ordering -> String # showList :: [Ordering] -> ShowS #
Generic Ordering
Instance details Defined in GHC.Generics Associated Types type Rep Ordering :: Type -> Type # Methods from :: Ordering -> Rep Ordering x # to :: Rep Ordering x -> Ordering #
Semigroup Ordering	Since: base-4.9.0.0
Instance details Defined in GHC.Base Methods (<>) :: Ordering -> Ordering -> Ordering # sconcat :: NonEmpty Ordering -> Ordering # stimes :: Integral b => b -> Ordering -> Ordering #
Monoid Ordering	Since: base-2.1
Instance details Defined in GHC.Base Methods mempty :: Ordering # mappend :: Ordering -> Ordering -> Ordering # mconcat :: [Ordering] -> Ordering #
NFData Ordering
Instance details Defined in Control.DeepSeq Methods rnf :: Ordering -> () #
Hashable Ordering
Instance details Defined in Data.Hashable.Class Methods hashWithSalt :: Int -> Ordering -> Int # hash :: Ordering -> Int #
type Rep Ordering	Since: base-4.6.0.0
Instance details Defined in GHC.Generics type Rep Ordering = D1 (MetaData "Ordering" "GHC.Types" "ghc-prim" False) (C1 (MetaCons "LT" PrefixI False) (U1 :: Type -> Type) :+: (C1 (MetaCons "EQ" PrefixI False) (U1 :: Type -> Type) :+: C1 (MetaCons "GT" PrefixI False) (U1 :: Type -> Type)))

data Ratio a #

Rational numbers, with numerator and denominator of some Integral type.

Note that Ratio's instances inherit the deficiencies from the type parameter's. For example, Ratio Natural's Num instance has similar problems to Natural's.

Constructors

!a :% !a

Instances

NFData1 Ratio	Available on `base >=4.9` Since: deepseq-1.4.3.0
Instance details Defined in Control.DeepSeq Methods liftRnf :: (a -> ()) -> Ratio a -> () #
Integral a => Enum (Ratio a)	Since: base-2.0.1
Instance details Defined in GHC.Real Methods succ :: Ratio a -> Ratio a # pred :: Ratio a -> Ratio a # toEnum :: Int -> Ratio a # fromEnum :: Ratio a -> Int # enumFrom :: Ratio a -> [Ratio a] # enumFromThen :: Ratio a -> Ratio a -> [Ratio a] # enumFromTo :: Ratio a -> Ratio a -> [Ratio a] # enumFromThenTo :: Ratio a -> Ratio a -> Ratio a -> [Ratio a] #
Eq a => Eq (Ratio a)	Since: base-2.1
Instance details Defined in GHC.Real Methods (==) :: Ratio a -> Ratio a -> Bool # (/=) :: Ratio a -> Ratio a -> Bool #
Integral a => Fractional (Ratio a)	Since: base-2.0.1
Instance details Defined in GHC.Real Methods (/) :: Ratio a -> Ratio a -> Ratio a # recip :: Ratio a -> Ratio a # fromRational :: Rational -> Ratio a #
Integral a => Num (Ratio a)	Since: base-2.0.1
Instance details Defined in GHC.Real Methods (+) :: Ratio a -> Ratio a -> Ratio a # (-) :: Ratio a -> Ratio a -> Ratio a # (*) :: Ratio a -> Ratio a -> Ratio a # negate :: Ratio a -> Ratio a # abs :: Ratio a -> Ratio a # signum :: Ratio a -> Ratio a # fromInteger :: Integer -> Ratio a #
Integral a => Ord (Ratio a)	Since: base-2.0.1
Instance details Defined in GHC.Real Methods compare :: Ratio a -> Ratio a -> Ordering # (<) :: Ratio a -> Ratio a -> Bool # (<=) :: Ratio a -> Ratio a -> Bool # (>) :: Ratio a -> Ratio a -> Bool # (>=) :: Ratio a -> Ratio a -> Bool # max :: Ratio a -> Ratio a -> Ratio a # min :: Ratio a -> Ratio a -> Ratio a #
(Integral a, Read a) => Read (Ratio a)	Since: base-2.1
Instance details Defined in GHC.Read Methods readsPrec :: Int -> ReadS (Ratio a) # readList :: ReadS [Ratio a] # readPrec :: ReadPrec (Ratio a) # readListPrec :: ReadPrec [Ratio a] #
Integral a => Real (Ratio a)	Since: base-2.0.1
Instance details Defined in GHC.Real Methods toRational :: Ratio a -> Rational #
Integral a => RealFrac (Ratio a)	Since: base-2.0.1
Instance details Defined in GHC.Real Methods properFraction :: Integral b => Ratio a -> (b, Ratio a) # truncate :: Integral b => Ratio a -> b # round :: Integral b => Ratio a -> b # ceiling :: Integral b => Ratio a -> b # floor :: Integral b => Ratio a -> b #
Show a => Show (Ratio a)	Since: base-2.0.1
Instance details Defined in GHC.Real Methods showsPrec :: Int -> Ratio a -> ShowS # show :: Ratio a -> String # showList :: [Ratio a] -> ShowS #
NFData a => NFData (Ratio a)
Instance details Defined in Control.DeepSeq Methods rnf :: Ratio a -> () #
Hashable a => Hashable (Ratio a)
Instance details Defined in Data.Hashable.Class Methods hashWithSalt :: Int -> Ratio a -> Int # hash :: Ratio a -> Int #

type Rational = Ratio Integer #

Arbitrary-precision rational numbers, represented as a ratio of two Integer values. A rational number may be constructed using the % operator.

data IO a #

A value of type IO a is a computation which, when performed, does some I/O before returning a value of type a.

There is really only one way to "perform" an I/O action: bind it to Main.main in your program. When your program is run, the I/O will be performed. It isn't possible to perform I/O from an arbitrary function, unless that function is itself in the IO monad and called at some point, directly or indirectly, from Main.main.

IO is a monad, so IO actions can be combined using either the do-notation or the >> and >>= operations from the Monad class.

Instances

Monad IO	Since: base-2.1
Instance details Defined in GHC.Base Methods (>>=) :: IO a -> (a -> IO b) -> IO b # (>>) :: IO a -> IO b -> IO b # return :: a -> IO a # fail :: String -> IO a #
Functor IO	Since: base-2.1
Instance details Defined in GHC.Base Methods fmap :: (a -> b) -> IO a -> IO b # (<$) :: a -> IO b -> IO a #
MonadFail IO	Since: base-4.9.0.0
Instance details Defined in Control.Monad.Fail Methods fail :: String -> IO a #
Applicative IO	Since: base-2.1
Instance details Defined in GHC.Base Methods pure :: a -> IO a # (<>) :: IO (a -> b) -> IO a -> IO b # liftA2 :: (a -> b -> c) -> IO a -> IO b -> IO c # (>) :: IO a -> IO b -> IO b # (<*) :: IO a -> IO b -> IO a #
MonadIO IO	Since: base-4.9.0.0
Instance details Defined in Control.Monad.IO.Class Methods liftIO :: IO a -> IO a #
Alternative IO	Since: base-4.9.0.0
Instance details Defined in GHC.Base Methods empty :: IO a # (<\|>) :: IO a -> IO a -> IO a # some :: IO a -> IO [a] # many :: IO a -> IO [a] #
MonadPlus IO	Since: base-4.9.0.0
Instance details Defined in GHC.Base Methods mzero :: IO a # mplus :: IO a -> IO a -> IO a #
MonadThrow IO
Instance details Defined in Control.Monad.Catch Methods throwM :: Exception e => e -> IO a #
MonadCatch IO
Instance details Defined in Control.Monad.Catch Methods catch :: Exception e => IO a -> (e -> IO a) -> IO a #
MonadMask IO
Instance details Defined in Control.Monad.Catch Methods mask :: ((forall a. IO a -> IO a) -> IO b) -> IO b # uninterruptibleMask :: ((forall a. IO a -> IO a) -> IO b) -> IO b # generalBracket :: IO a -> (a -> ExitCase b -> IO c) -> (a -> IO b) -> IO (b, c) #
MonadError IOException IO
Instance details Defined in Control.Monad.Error.Class Methods throwError :: IOException -> IO a # catchError :: IO a -> (IOException -> IO a) -> IO a #
Semigroup a => Semigroup (IO a)	Since: base-4.10.0.0
Instance details Defined in GHC.Base Methods (<>) :: IO a -> IO a -> IO a # sconcat :: NonEmpty (IO a) -> IO a # stimes :: Integral b => b -> IO a -> IO a #
Monoid a => Monoid (IO a)	Since: base-4.9.0.0
Instance details Defined in GHC.Base Methods mempty :: IO a # mappend :: IO a -> IO a -> IO a # mconcat :: [IO a] -> IO a #

data Word #

A Word is an unsigned integral type, with the same size as Int.

Instances

Bounded Word	Since: base-2.1
Instance details Defined in GHC.Enum Methods minBound :: Word # maxBound :: Word #
Enum Word	Since: base-2.1
Instance details Defined in GHC.Enum Methods succ :: Word -> Word # pred :: Word -> Word # toEnum :: Int -> Word # fromEnum :: Word -> Int # enumFrom :: Word -> [Word] # enumFromThen :: Word -> Word -> [Word] # enumFromTo :: Word -> Word -> [Word] # enumFromThenTo :: Word -> Word -> Word -> [Word] #
Eq Word
Instance details Defined in GHC.Classes Methods (==) :: Word -> Word -> Bool # (/=) :: Word -> Word -> Bool #
Integral Word	Since: base-2.1
Instance details Defined in GHC.Real Methods quot :: Word -> Word -> Word # rem :: Word -> Word -> Word # div :: Word -> Word -> Word # mod :: Word -> Word -> Word # quotRem :: Word -> Word -> (Word, Word) # divMod :: Word -> Word -> (Word, Word) # toInteger :: Word -> Integer #
Num Word	Since: base-2.1
Instance details Defined in GHC.Num Methods (+) :: Word -> Word -> Word # (-) :: Word -> Word -> Word # (*) :: Word -> Word -> Word # negate :: Word -> Word # abs :: Word -> Word # signum :: Word -> Word # fromInteger :: Integer -> Word #
Ord Word
Instance details Defined in GHC.Classes Methods compare :: Word -> Word -> Ordering # (<) :: Word -> Word -> Bool # (<=) :: Word -> Word -> Bool # (>) :: Word -> Word -> Bool # (>=) :: Word -> Word -> Bool # max :: Word -> Word -> Word # min :: Word -> Word -> Word #
Read Word	Since: base-4.5.0.0
Instance details Defined in GHC.Read Methods readsPrec :: Int -> ReadS Word # readList :: ReadS [Word] # readPrec :: ReadPrec Word # readListPrec :: ReadPrec [Word] #
Real Word	Since: base-2.1
Instance details Defined in GHC.Real Methods toRational :: Word -> Rational #
Show Word	Since: base-2.1
Instance details Defined in GHC.Show Methods showsPrec :: Int -> Word -> ShowS # show :: Word -> String # showList :: [Word] -> ShowS #
Bits Word	Since: base-2.1
Instance details Defined in Data.Bits Methods (.&.) :: Word -> Word -> Word # (.\|.) :: Word -> Word -> Word # xor :: Word -> Word -> Word # complement :: Word -> Word # shift :: Word -> Int -> Word # rotate :: Word -> Int -> Word # zeroBits :: Word # bit :: Int -> Word # setBit :: Word -> Int -> Word # clearBit :: Word -> Int -> Word # complementBit :: Word -> Int -> Word # testBit :: Word -> Int -> Bool # bitSizeMaybe :: Word -> Maybe Int # bitSize :: Word -> Int # isSigned :: Word -> Bool # shiftL :: Word -> Int -> Word # unsafeShiftL :: Word -> Int -> Word # shiftR :: Word -> Int -> Word # unsafeShiftR :: Word -> Int -> Word # rotateL :: Word -> Int -> Word # rotateR :: Word -> Int -> Word # popCount :: Word -> Int #
FiniteBits Word	Since: base-4.6.0.0
Instance details Defined in Data.Bits Methods finiteBitSize :: Word -> Int # countLeadingZeros :: Word -> Int # countTrailingZeros :: Word -> Int #
NFData Word
Instance details Defined in Control.DeepSeq Methods rnf :: Word -> () #
Hashable Word
Instance details Defined in Data.Hashable.Class Methods hashWithSalt :: Int -> Word -> Int # hash :: Word -> Int #
Generic1 (URec Word :: k -> Type)
Instance details Defined in GHC.Generics Associated Types type Rep1 (URec Word) :: k -> Type # Methods from1 :: URec Word a -> Rep1 (URec Word) a # to1 :: Rep1 (URec Word) a -> URec Word a #
Functor (URec Word :: Type -> Type)	Since: base-4.9.0.0
Instance details Defined in GHC.Generics Methods fmap :: (a -> b) -> URec Word a -> URec Word b # (<$) :: a -> URec Word b -> URec Word a #
Foldable (URec Word :: Type -> Type)	Since: base-4.9.0.0
Instance details Defined in Data.Foldable Methods fold :: Monoid m => URec Word m -> m # foldMap :: Monoid m => (a -> m) -> URec Word a -> m # foldr :: (a -> b -> b) -> b -> URec Word a -> b # foldr' :: (a -> b -> b) -> b -> URec Word a -> b # foldl :: (b -> a -> b) -> b -> URec Word a -> b # foldl' :: (b -> a -> b) -> b -> URec Word a -> b # foldr1 :: (a -> a -> a) -> URec Word a -> a # foldl1 :: (a -> a -> a) -> URec Word a -> a # toList :: URec Word a -> [a] # null :: URec Word a -> Bool # length :: URec Word a -> Int # elem :: Eq a => a -> URec Word a -> Bool # maximum :: Ord a => URec Word a -> a # minimum :: Ord a => URec Word a -> a # sum :: Num a => URec Word a -> a # product :: Num a => URec Word a -> a #
Traversable (URec Word :: Type -> Type)	Since: base-4.9.0.0
Instance details Defined in Data.Traversable Methods traverse :: Applicative f => (a -> f b) -> URec Word a -> f (URec Word b) # sequenceA :: Applicative f => URec Word (f a) -> f (URec Word a) # mapM :: Monad m => (a -> m b) -> URec Word a -> m (URec Word b) # sequence :: Monad m => URec Word (m a) -> m (URec Word a) #
Eq (URec Word p)	Since: base-4.9.0.0
Instance details Defined in GHC.Generics Methods (==) :: URec Word p -> URec Word p -> Bool # (/=) :: URec Word p -> URec Word p -> Bool #
Ord (URec Word p)	Since: base-4.9.0.0
Instance details Defined in GHC.Generics Methods compare :: URec Word p -> URec Word p -> Ordering # (<) :: URec Word p -> URec Word p -> Bool # (<=) :: URec Word p -> URec Word p -> Bool # (>) :: URec Word p -> URec Word p -> Bool # (>=) :: URec Word p -> URec Word p -> Bool # max :: URec Word p -> URec Word p -> URec Word p # min :: URec Word p -> URec Word p -> URec Word p #
Show (URec Word p)	Since: base-4.9.0.0
Instance details Defined in GHC.Generics Methods showsPrec :: Int -> URec Word p -> ShowS # show :: URec Word p -> String # showList :: [URec Word p] -> ShowS #
Generic (URec Word p)
Instance details Defined in GHC.Generics Associated Types type Rep (URec Word p) :: Type -> Type # Methods from :: URec Word p -> Rep (URec Word p) x # to :: Rep (URec Word p) x -> URec Word p #
data URec Word (p :: k)	Used for marking occurrences of `Word#` Since: base-4.9.0.0
Instance details Defined in GHC.Generics data URec Word (p :: k) = UWord { uWord# :: Word# }
type Rep1 (URec Word :: k -> Type)	Since: base-4.9.0.0
Instance details Defined in GHC.Generics type Rep1 (URec Word :: k -> Type) = D1 (MetaData "URec" "GHC.Generics" "base" False) (C1 (MetaCons "UWord" PrefixI True) (S1 (MetaSel (Just "uWord#") NoSourceUnpackedness NoSourceStrictness DecidedLazy) (UWord :: k -> Type)))
type Rep (URec Word p)	Since: base-4.9.0.0
Instance details Defined in GHC.Generics type Rep (URec Word p) = D1 (MetaData "URec" "GHC.Generics" "base" False) (C1 (MetaCons "UWord" PrefixI True) (S1 (MetaSel (Just "uWord#") NoSourceUnpackedness NoSourceStrictness DecidedLazy) (UWord :: Type -> Type)))

data Word8 #

8-bit unsigned integer type

Instances

Bounded Word8	Since: base-2.1
Instance details Defined in GHC.Word Methods minBound :: Word8 # maxBound :: Word8 #
Enum Word8	Since: base-2.1
Instance details Defined in GHC.Word Methods succ :: Word8 -> Word8 # pred :: Word8 -> Word8 # toEnum :: Int -> Word8 # fromEnum :: Word8 -> Int # enumFrom :: Word8 -> [Word8] # enumFromThen :: Word8 -> Word8 -> [Word8] # enumFromTo :: Word8 -> Word8 -> [Word8] # enumFromThenTo :: Word8 -> Word8 -> Word8 -> [Word8] #
Eq Word8	Since: base-2.1
Instance details Defined in GHC.Word Methods (==) :: Word8 -> Word8 -> Bool # (/=) :: Word8 -> Word8 -> Bool #
Integral Word8	Since: base-2.1
Instance details Defined in GHC.Word Methods quot :: Word8 -> Word8 -> Word8 # rem :: Word8 -> Word8 -> Word8 # div :: Word8 -> Word8 -> Word8 # mod :: Word8 -> Word8 -> Word8 # quotRem :: Word8 -> Word8 -> (Word8, Word8) # divMod :: Word8 -> Word8 -> (Word8, Word8) # toInteger :: Word8 -> Integer #
Num Word8	Since: base-2.1
Instance details Defined in GHC.Word Methods (+) :: Word8 -> Word8 -> Word8 # (-) :: Word8 -> Word8 -> Word8 # (*) :: Word8 -> Word8 -> Word8 # negate :: Word8 -> Word8 # abs :: Word8 -> Word8 # signum :: Word8 -> Word8 # fromInteger :: Integer -> Word8 #
Ord Word8	Since: base-2.1
Instance details Defined in GHC.Word Methods compare :: Word8 -> Word8 -> Ordering # (<) :: Word8 -> Word8 -> Bool # (<=) :: Word8 -> Word8 -> Bool # (>) :: Word8 -> Word8 -> Bool # (>=) :: Word8 -> Word8 -> Bool # max :: Word8 -> Word8 -> Word8 # min :: Word8 -> Word8 -> Word8 #
Read Word8	Since: base-2.1
Instance details Defined in GHC.Read Methods readsPrec :: Int -> ReadS Word8 # readList :: ReadS [Word8] # readPrec :: ReadPrec Word8 # readListPrec :: ReadPrec [Word8] #
Real Word8	Since: base-2.1
Instance details Defined in GHC.Word Methods toRational :: Word8 -> Rational #
Show Word8	Since: base-2.1
Instance details Defined in GHC.Word Methods showsPrec :: Int -> Word8 -> ShowS # show :: Word8 -> String # showList :: [Word8] -> ShowS #
Ix Word8	Since: base-2.1
Instance details Defined in GHC.Word Methods range :: (Word8, Word8) -> [Word8] # index :: (Word8, Word8) -> Word8 -> Int # unsafeIndex :: (Word8, Word8) -> Word8 -> Int inRange :: (Word8, Word8) -> Word8 -> Bool # rangeSize :: (Word8, Word8) -> Int # unsafeRangeSize :: (Word8, Word8) -> Int
Bits Word8	Since: base-2.1
Instance details Defined in GHC.Word Methods (.&.) :: Word8 -> Word8 -> Word8 # (.\|.) :: Word8 -> Word8 -> Word8 # xor :: Word8 -> Word8 -> Word8 # complement :: Word8 -> Word8 # shift :: Word8 -> Int -> Word8 # rotate :: Word8 -> Int -> Word8 # zeroBits :: Word8 # bit :: Int -> Word8 # setBit :: Word8 -> Int -> Word8 # clearBit :: Word8 -> Int -> Word8 # complementBit :: Word8 -> Int -> Word8 # testBit :: Word8 -> Int -> Bool # bitSizeMaybe :: Word8 -> Maybe Int # bitSize :: Word8 -> Int # isSigned :: Word8 -> Bool # shiftL :: Word8 -> Int -> Word8 # unsafeShiftL :: Word8 -> Int -> Word8 # shiftR :: Word8 -> Int -> Word8 # unsafeShiftR :: Word8 -> Int -> Word8 # rotateL :: Word8 -> Int -> Word8 # rotateR :: Word8 -> Int -> Word8 # popCount :: Word8 -> Int #
FiniteBits Word8	Since: base-4.6.0.0
Instance details Defined in GHC.Word Methods finiteBitSize :: Word8 -> Int # countLeadingZeros :: Word8 -> Int # countTrailingZeros :: Word8 -> Int #
NFData Word8
Instance details Defined in Control.DeepSeq Methods rnf :: Word8 -> () #
Hashable Word8
Instance details Defined in Data.Hashable.Class Methods hashWithSalt :: Int -> Word8 -> Int # hash :: Word8 -> Int #

data Word16 #

16-bit unsigned integer type

Instances

Bounded Word16	Since: base-2.1
Instance details Defined in GHC.Word Methods minBound :: Word16 # maxBound :: Word16 #
Enum Word16	Since: base-2.1
Instance details Defined in GHC.Word Methods succ :: Word16 -> Word16 # pred :: Word16 -> Word16 # toEnum :: Int -> Word16 # fromEnum :: Word16 -> Int # enumFrom :: Word16 -> [Word16] # enumFromThen :: Word16 -> Word16 -> [Word16] # enumFromTo :: Word16 -> Word16 -> [Word16] # enumFromThenTo :: Word16 -> Word16 -> Word16 -> [Word16] #
Eq Word16	Since: base-2.1
Instance details Defined in GHC.Word Methods (==) :: Word16 -> Word16 -> Bool # (/=) :: Word16 -> Word16 -> Bool #
Integral Word16	Since: base-2.1
Instance details Defined in GHC.Word Methods quot :: Word16 -> Word16 -> Word16 # rem :: Word16 -> Word16 -> Word16 # div :: Word16 -> Word16 -> Word16 # mod :: Word16 -> Word16 -> Word16 # quotRem :: Word16 -> Word16 -> (Word16, Word16) # divMod :: Word16 -> Word16 -> (Word16, Word16) # toInteger :: Word16 -> Integer #
Num Word16	Since: base-2.1
Instance details Defined in GHC.Word Methods (+) :: Word16 -> Word16 -> Word16 # (-) :: Word16 -> Word16 -> Word16 # (*) :: Word16 -> Word16 -> Word16 # negate :: Word16 -> Word16 # abs :: Word16 -> Word16 # signum :: Word16 -> Word16 # fromInteger :: Integer -> Word16 #
Ord Word16	Since: base-2.1
Instance details Defined in GHC.Word Methods compare :: Word16 -> Word16 -> Ordering # (<) :: Word16 -> Word16 -> Bool # (<=) :: Word16 -> Word16 -> Bool # (>) :: Word16 -> Word16 -> Bool # (>=) :: Word16 -> Word16 -> Bool # max :: Word16 -> Word16 -> Word16 # min :: Word16 -> Word16 -> Word16 #
Read Word16	Since: base-2.1
Instance details Defined in GHC.Read Methods readsPrec :: Int -> ReadS Word16 # readList :: ReadS [Word16] # readPrec :: ReadPrec Word16 # readListPrec :: ReadPrec [Word16] #
Real Word16	Since: base-2.1
Instance details Defined in GHC.Word Methods toRational :: Word16 -> Rational #
Show Word16	Since: base-2.1
Instance details Defined in GHC.Word Methods showsPrec :: Int -> Word16 -> ShowS # show :: Word16 -> String # showList :: [Word16] -> ShowS #
Ix Word16	Since: base-2.1
Instance details Defined in GHC.Word Methods range :: (Word16, Word16) -> [Word16] # index :: (Word16, Word16) -> Word16 -> Int # unsafeIndex :: (Word16, Word16) -> Word16 -> Int inRange :: (Word16, Word16) -> Word16 -> Bool # rangeSize :: (Word16, Word16) -> Int # unsafeRangeSize :: (Word16, Word16) -> Int
Bits Word16	Since: base-2.1
Instance details Defined in GHC.Word Methods (.&.) :: Word16 -> Word16 -> Word16 # (.\|.) :: Word16 -> Word16 -> Word16 # xor :: Word16 -> Word16 -> Word16 # complement :: Word16 -> Word16 # shift :: Word16 -> Int -> Word16 # rotate :: Word16 -> Int -> Word16 # zeroBits :: Word16 # bit :: Int -> Word16 # setBit :: Word16 -> Int -> Word16 # clearBit :: Word16 -> Int -> Word16 # complementBit :: Word16 -> Int -> Word16 # testBit :: Word16 -> Int -> Bool # bitSizeMaybe :: Word16 -> Maybe Int # bitSize :: Word16 -> Int # isSigned :: Word16 -> Bool # shiftL :: Word16 -> Int -> Word16 # unsafeShiftL :: Word16 -> Int -> Word16 # shiftR :: Word16 -> Int -> Word16 # unsafeShiftR :: Word16 -> Int -> Word16 # rotateL :: Word16 -> Int -> Word16 # rotateR :: Word16 -> Int -> Word16 # popCount :: Word16 -> Int #
FiniteBits Word16	Since: base-4.6.0.0
Instance details Defined in GHC.Word Methods finiteBitSize :: Word16 -> Int # countLeadingZeros :: Word16 -> Int # countTrailingZeros :: Word16 -> Int #
NFData Word16
Instance details Defined in Control.DeepSeq Methods rnf :: Word16 -> () #
Hashable Word16
Instance details Defined in Data.Hashable.Class Methods hashWithSalt :: Int -> Word16 -> Int # hash :: Word16 -> Int #

data Word32 #

32-bit unsigned integer type

Instances

Bounded Word32	Since: base-2.1
Instance details Defined in GHC.Word Methods minBound :: Word32 # maxBound :: Word32 #
Enum Word32	Since: base-2.1
Instance details Defined in GHC.Word Methods succ :: Word32 -> Word32 # pred :: Word32 -> Word32 # toEnum :: Int -> Word32 # fromEnum :: Word32 -> Int # enumFrom :: Word32 -> [Word32] # enumFromThen :: Word32 -> Word32 -> [Word32] # enumFromTo :: Word32 -> Word32 -> [Word32] # enumFromThenTo :: Word32 -> Word32 -> Word32 -> [Word32] #
Eq Word32	Since: base-2.1
Instance details Defined in GHC.Word Methods (==) :: Word32 -> Word32 -> Bool # (/=) :: Word32 -> Word32 -> Bool #
Integral Word32	Since: base-2.1
Instance details Defined in GHC.Word Methods quot :: Word32 -> Word32 -> Word32 # rem :: Word32 -> Word32 -> Word32 # div :: Word32 -> Word32 -> Word32 # mod :: Word32 -> Word32 -> Word32 # quotRem :: Word32 -> Word32 -> (Word32, Word32) # divMod :: Word32 -> Word32 -> (Word32, Word32) # toInteger :: Word32 -> Integer #
Num Word32	Since: base-2.1
Instance details Defined in GHC.Word Methods (+) :: Word32 -> Word32 -> Word32 # (-) :: Word32 -> Word32 -> Word32 # (*) :: Word32 -> Word32 -> Word32 # negate :: Word32 -> Word32 # abs :: Word32 -> Word32 # signum :: Word32 -> Word32 # fromInteger :: Integer -> Word32 #
Ord Word32	Since: base-2.1
Instance details Defined in GHC.Word Methods compare :: Word32 -> Word32 -> Ordering # (<) :: Word32 -> Word32 -> Bool # (<=) :: Word32 -> Word32 -> Bool # (>) :: Word32 -> Word32 -> Bool # (>=) :: Word32 -> Word32 -> Bool # max :: Word32 -> Word32 -> Word32 # min :: Word32 -> Word32 -> Word32 #
Read Word32	Since: base-2.1
Instance details Defined in GHC.Read Methods readsPrec :: Int -> ReadS Word32 # readList :: ReadS [Word32] # readPrec :: ReadPrec Word32 # readListPrec :: ReadPrec [Word32] #
Real Word32	Since: base-2.1
Instance details Defined in GHC.Word Methods toRational :: Word32 -> Rational #
Show Word32	Since: base-2.1
Instance details Defined in GHC.Word Methods showsPrec :: Int -> Word32 -> ShowS # show :: Word32 -> String # showList :: [Word32] -> ShowS #
Ix Word32	Since: base-2.1
Instance details Defined in GHC.Word Methods range :: (Word32, Word32) -> [Word32] # index :: (Word32, Word32) -> Word32 -> Int # unsafeIndex :: (Word32, Word32) -> Word32 -> Int inRange :: (Word32, Word32) -> Word32 -> Bool # rangeSize :: (Word32, Word32) -> Int # unsafeRangeSize :: (Word32, Word32) -> Int
Bits Word32	Since: base-2.1
Instance details Defined in GHC.Word Methods (.&.) :: Word32 -> Word32 -> Word32 # (.\|.) :: Word32 -> Word32 -> Word32 # xor :: Word32 -> Word32 -> Word32 # complement :: Word32 -> Word32 # shift :: Word32 -> Int -> Word32 # rotate :: Word32 -> Int -> Word32 # zeroBits :: Word32 # bit :: Int -> Word32 # setBit :: Word32 -> Int -> Word32 # clearBit :: Word32 -> Int -> Word32 # complementBit :: Word32 -> Int -> Word32 # testBit :: Word32 -> Int -> Bool # bitSizeMaybe :: Word32 -> Maybe Int # bitSize :: Word32 -> Int # isSigned :: Word32 -> Bool # shiftL :: Word32 -> Int -> Word32 # unsafeShiftL :: Word32 -> Int -> Word32 # shiftR :: Word32 -> Int -> Word32 # unsafeShiftR :: Word32 -> Int -> Word32 # rotateL :: Word32 -> Int -> Word32 # rotateR :: Word32 -> Int -> Word32 # popCount :: Word32 -> Int #
FiniteBits Word32	Since: base-4.6.0.0
Instance details Defined in GHC.Word Methods finiteBitSize :: Word32 -> Int # countLeadingZeros :: Word32 -> Int # countTrailingZeros :: Word32 -> Int #
NFData Word32
Instance details Defined in Control.DeepSeq Methods rnf :: Word32 -> () #
Hashable Word32
Instance details Defined in Data.Hashable.Class Methods hashWithSalt :: Int -> Word32 -> Int # hash :: Word32 -> Int #

data Word64 #

64-bit unsigned integer type

Instances

Bounded Word64	Since: base-2.1
Instance details Defined in GHC.Word Methods minBound :: Word64 # maxBound :: Word64 #
Enum Word64	Since: base-2.1
Instance details Defined in GHC.Word Methods succ :: Word64 -> Word64 # pred :: Word64 -> Word64 # toEnum :: Int -> Word64 # fromEnum :: Word64 -> Int # enumFrom :: Word64 -> [Word64] # enumFromThen :: Word64 -> Word64 -> [Word64] # enumFromTo :: Word64 -> Word64 -> [Word64] # enumFromThenTo :: Word64 -> Word64 -> Word64 -> [Word64] #
Eq Word64	Since: base-2.1
Instance details Defined in GHC.Word Methods (==) :: Word64 -> Word64 -> Bool # (/=) :: Word64 -> Word64 -> Bool #
Integral Word64	Since: base-2.1
Instance details Defined in GHC.Word Methods quot :: Word64 -> Word64 -> Word64 # rem :: Word64 -> Word64 -> Word64 # div :: Word64 -> Word64 -> Word64 # mod :: Word64 -> Word64 -> Word64 # quotRem :: Word64 -> Word64 -> (Word64, Word64) # divMod :: Word64 -> Word64 -> (Word64, Word64) # toInteger :: Word64 -> Integer #
Num Word64	Since: base-2.1
Instance details Defined in GHC.Word Methods (+) :: Word64 -> Word64 -> Word64 # (-) :: Word64 -> Word64 -> Word64 # (*) :: Word64 -> Word64 -> Word64 # negate :: Word64 -> Word64 # abs :: Word64 -> Word64 # signum :: Word64 -> Word64 # fromInteger :: Integer -> Word64 #
Ord Word64	Since: base-2.1
Instance details Defined in GHC.Word Methods compare :: Word64 -> Word64 -> Ordering # (<) :: Word64 -> Word64 -> Bool # (<=) :: Word64 -> Word64 -> Bool # (>) :: Word64 -> Word64 -> Bool # (>=) :: Word64 -> Word64 -> Bool # max :: Word64 -> Word64 -> Word64 # min :: Word64 -> Word64 -> Word64 #
Read Word64	Since: base-2.1
Instance details Defined in GHC.Read Methods readsPrec :: Int -> ReadS Word64 # readList :: ReadS [Word64] # readPrec :: ReadPrec Word64 # readListPrec :: ReadPrec [Word64] #
Real Word64	Since: base-2.1
Instance details Defined in GHC.Word Methods toRational :: Word64 -> Rational #
Show Word64	Since: base-2.1
Instance details Defined in GHC.Word Methods showsPrec :: Int -> Word64 -> ShowS # show :: Word64 -> String # showList :: [Word64] -> ShowS #
Ix Word64	Since: base-2.1
Instance details Defined in GHC.Word Methods range :: (Word64, Word64) -> [Word64] # index :: (Word64, Word64) -> Word64 -> Int # unsafeIndex :: (Word64, Word64) -> Word64 -> Int inRange :: (Word64, Word64) -> Word64 -> Bool # rangeSize :: (Word64, Word64) -> Int # unsafeRangeSize :: (Word64, Word64) -> Int
Bits Word64	Since: base-2.1
Instance details Defined in GHC.Word Methods (.&.) :: Word64 -> Word64 -> Word64 # (.\|.) :: Word64 -> Word64 -> Word64 # xor :: Word64 -> Word64 -> Word64 # complement :: Word64 -> Word64 # shift :: Word64 -> Int -> Word64 # rotate :: Word64 -> Int -> Word64 # zeroBits :: Word64 # bit :: Int -> Word64 # setBit :: Word64 -> Int -> Word64 # clearBit :: Word64 -> Int -> Word64 # complementBit :: Word64 -> Int -> Word64 # testBit :: Word64 -> Int -> Bool # bitSizeMaybe :: Word64 -> Maybe Int # bitSize :: Word64 -> Int # isSigned :: Word64 -> Bool # shiftL :: Word64 -> Int -> Word64 # unsafeShiftL :: Word64 -> Int -> Word64 # shiftR :: Word64 -> Int -> Word64 # unsafeShiftR :: Word64 -> Int -> Word64 # rotateL :: Word64 -> Int -> Word64 # rotateR :: Word64 -> Int -> Word64 # popCount :: Word64 -> Int #
FiniteBits Word64	Since: base-4.6.0.0
Instance details Defined in GHC.Word Methods finiteBitSize :: Word64 -> Int # countLeadingZeros :: Word64 -> Int # countTrailingZeros :: Word64 -> Int #
NFData Word64
Instance details Defined in Control.DeepSeq Methods rnf :: Word64 -> () #
Hashable Word64
Instance details Defined in Data.Hashable.Class Methods hashWithSalt :: Int -> Word64 -> Int # hash :: Word64 -> Int #

data Ptr a #

A value of type Ptr a represents a pointer to an object, or an array of objects, which may be marshalled to or from Haskell values of type a.

The type a will often be an instance of class Storable which provides the marshalling operations. However this is not essential, and you can provide your own operations to access the pointer. For example you might write small foreign functions to get or set the fields of a C struct.

Instances

NFData1 Ptr	Since: deepseq-1.4.3.0
Instance details Defined in Control.DeepSeq Methods liftRnf :: (a -> ()) -> Ptr a -> () #
Generic1 (URec (Ptr ()) :: k -> Type)
Instance details Defined in GHC.Generics Associated Types type Rep1 (URec (Ptr ())) :: k -> Type # Methods from1 :: URec (Ptr ()) a -> Rep1 (URec (Ptr ())) a # to1 :: Rep1 (URec (Ptr ())) a -> URec (Ptr ()) a #
Eq (Ptr a)	Since: base-2.1
Instance details Defined in GHC.Ptr Methods (==) :: Ptr a -> Ptr a -> Bool # (/=) :: Ptr a -> Ptr a -> Bool #
Ord (Ptr a)	Since: base-2.1
Instance details Defined in GHC.Ptr Methods compare :: Ptr a -> Ptr a -> Ordering # (<) :: Ptr a -> Ptr a -> Bool # (<=) :: Ptr a -> Ptr a -> Bool # (>) :: Ptr a -> Ptr a -> Bool # (>=) :: Ptr a -> Ptr a -> Bool # max :: Ptr a -> Ptr a -> Ptr a # min :: Ptr a -> Ptr a -> Ptr a #
Show (Ptr a)	Since: base-2.1
Instance details Defined in GHC.Ptr Methods showsPrec :: Int -> Ptr a -> ShowS # show :: Ptr a -> String # showList :: [Ptr a] -> ShowS #
NFData (Ptr a)	Since: deepseq-1.4.2.0
Instance details Defined in Control.DeepSeq Methods rnf :: Ptr a -> () #
Hashable (Ptr a)
Instance details Defined in Data.Hashable.Class Methods hashWithSalt :: Int -> Ptr a -> Int # hash :: Ptr a -> Int #
Functor (URec (Ptr ()) :: Type -> Type)	Since: base-4.9.0.0
Instance details Defined in GHC.Generics Methods fmap :: (a -> b) -> URec (Ptr ()) a -> URec (Ptr ()) b # (<$) :: a -> URec (Ptr ()) b -> URec (Ptr ()) a #
Foldable (URec (Ptr ()) :: Type -> Type)	Since: base-4.9.0.0
Instance details Defined in Data.Foldable Methods fold :: Monoid m => URec (Ptr ()) m -> m # foldMap :: Monoid m => (a -> m) -> URec (Ptr ()) a -> m # foldr :: (a -> b -> b) -> b -> URec (Ptr ()) a -> b # foldr' :: (a -> b -> b) -> b -> URec (Ptr ()) a -> b # foldl :: (b -> a -> b) -> b -> URec (Ptr ()) a -> b # foldl' :: (b -> a -> b) -> b -> URec (Ptr ()) a -> b # foldr1 :: (a -> a -> a) -> URec (Ptr ()) a -> a # foldl1 :: (a -> a -> a) -> URec (Ptr ()) a -> a # toList :: URec (Ptr ()) a -> [a] # null :: URec (Ptr ()) a -> Bool # length :: URec (Ptr ()) a -> Int # elem :: Eq a => a -> URec (Ptr ()) a -> Bool # maximum :: Ord a => URec (Ptr ()) a -> a # minimum :: Ord a => URec (Ptr ()) a -> a # sum :: Num a => URec (Ptr ()) a -> a # product :: Num a => URec (Ptr ()) a -> a #
Traversable (URec (Ptr ()) :: Type -> Type)	Since: base-4.9.0.0
Instance details Defined in Data.Traversable Methods traverse :: Applicative f => (a -> f b) -> URec (Ptr ()) a -> f (URec (Ptr ()) b) # sequenceA :: Applicative f => URec (Ptr ()) (f a) -> f (URec (Ptr ()) a) # mapM :: Monad m => (a -> m b) -> URec (Ptr ()) a -> m (URec (Ptr ()) b) # sequence :: Monad m => URec (Ptr ()) (m a) -> m (URec (Ptr ()) a) #
Eq (URec (Ptr ()) p)	Since: base-4.9.0.0
Instance details Defined in GHC.Generics Methods (==) :: URec (Ptr ()) p -> URec (Ptr ()) p -> Bool # (/=) :: URec (Ptr ()) p -> URec (Ptr ()) p -> Bool #
Ord (URec (Ptr ()) p)	Since: base-4.9.0.0
Instance details Defined in GHC.Generics Methods compare :: URec (Ptr ()) p -> URec (Ptr ()) p -> Ordering # (<) :: URec (Ptr ()) p -> URec (Ptr ()) p -> Bool # (<=) :: URec (Ptr ()) p -> URec (Ptr ()) p -> Bool # (>) :: URec (Ptr ()) p -> URec (Ptr ()) p -> Bool # (>=) :: URec (Ptr ()) p -> URec (Ptr ()) p -> Bool # max :: URec (Ptr ()) p -> URec (Ptr ()) p -> URec (Ptr ()) p # min :: URec (Ptr ()) p -> URec (Ptr ()) p -> URec (Ptr ()) p #
Generic (URec (Ptr ()) p)
Instance details Defined in GHC.Generics Associated Types type Rep (URec (Ptr ()) p) :: Type -> Type # Methods from :: URec (Ptr ()) p -> Rep (URec (Ptr ()) p) x # to :: Rep (URec (Ptr ()) p) x -> URec (Ptr ()) p #
data URec (Ptr ()) (p :: k)	Used for marking occurrences of `Addr#` Since: base-4.9.0.0
Instance details Defined in GHC.Generics data URec (Ptr ()) (p :: k) = UAddr { uAddr# :: Addr# }
type Rep1 (URec (Ptr ()) :: k -> Type)	Since: base-4.9.0.0
Instance details Defined in GHC.Generics type Rep1 (URec (Ptr ()) :: k -> Type) = D1 (MetaData "URec" "GHC.Generics" "base" False) (C1 (MetaCons "UAddr" PrefixI True) (S1 (MetaSel (Just "uAddr#") NoSourceUnpackedness NoSourceStrictness DecidedLazy) (UAddr :: k -> Type)))
type Rep (URec (Ptr ()) p)	Since: base-4.9.0.0
Instance details Defined in GHC.Generics type Rep (URec (Ptr ()) p) = D1 (MetaData "URec" "GHC.Generics" "base" False) (C1 (MetaCons "UAddr" PrefixI True) (S1 (MetaSel (Just "uAddr#") NoSourceUnpackedness NoSourceStrictness DecidedLazy) (UAddr :: Type -> Type)))

data FunPtr a #

A value of type FunPtr a is a pointer to a function callable from foreign code. The type a will normally be a foreign type, a function type with zero or more arguments where

the argument types are marshallable foreign types, i.e. Char, Int, Double, Float, Bool, Int8, Int16, Int32, Int64, Word8, Word16, Word32, Word64, Ptr a, FunPtr a, StablePtr a or a renaming of any of these using newtype.
the return type is either a marshallable foreign type or has the form IO t where t is a marshallable foreign type or ().

A value of type FunPtr a may be a pointer to a foreign function, either returned by another foreign function or imported with a a static address import like

foreign import ccall "stdlib.h &free"
  p_free :: FunPtr (Ptr a -> IO ())

or a pointer to a Haskell function created using a wrapper stub declared to produce a FunPtr of the correct type. For example:

type Compare = Int -> Int -> Bool
foreign import ccall "wrapper"
  mkCompare :: Compare -> IO (FunPtr Compare)

Calls to wrapper stubs like mkCompare allocate storage, which should be released with freeHaskellFunPtr when no longer required.

To convert FunPtr values to corresponding Haskell functions, one can define a dynamic stub for the specific foreign type, e.g.

type IntFunction = CInt -> IO ()
foreign import ccall "dynamic"
  mkFun :: FunPtr IntFunction -> IntFunction

Instances

NFData1 FunPtr	Since: deepseq-1.4.3.0
Instance details Defined in Control.DeepSeq Methods liftRnf :: (a -> ()) -> FunPtr a -> () #
Eq (FunPtr a)
Instance details Defined in GHC.Ptr Methods (==) :: FunPtr a -> FunPtr a -> Bool # (/=) :: FunPtr a -> FunPtr a -> Bool #
Ord (FunPtr a)
Instance details Defined in GHC.Ptr Methods compare :: FunPtr a -> FunPtr a -> Ordering # (<) :: FunPtr a -> FunPtr a -> Bool # (<=) :: FunPtr a -> FunPtr a -> Bool # (>) :: FunPtr a -> FunPtr a -> Bool # (>=) :: FunPtr a -> FunPtr a -> Bool # max :: FunPtr a -> FunPtr a -> FunPtr a # min :: FunPtr a -> FunPtr a -> FunPtr a #
Show (FunPtr a)	Since: base-2.1
Instance details Defined in GHC.Ptr Methods showsPrec :: Int -> FunPtr a -> ShowS # show :: FunPtr a -> String # showList :: [FunPtr a] -> ShowS #
NFData (FunPtr a)	Since: deepseq-1.4.2.0
Instance details Defined in Control.DeepSeq Methods rnf :: FunPtr a -> () #
Hashable (FunPtr a)
Instance details Defined in Data.Hashable.Class Methods hashWithSalt :: Int -> FunPtr a -> Int # hash :: FunPtr a -> Int #

data Either a b #

The Either type represents values with two possibilities: a value of type Either a b is either Left a or Right b.

The Either type is sometimes used to represent a value which is either correct or an error; by convention, the Left constructor is used to hold an error value and the Right constructor is used to hold a correct value (mnemonic: "right" also means "correct").

Examples

Expand

The type Either String Int is the type of values which can be either a String or an Int. The Left constructor can be used only on Strings, and the Right constructor can be used only on Ints:

>>> let s = Left "foo" :: Either String Int
>>> s
Left "foo"
>>> let n = Right 3 :: Either String Int
>>> n
Right 3
>>> :type s
s :: Either String Int
>>> :type n
n :: Either String Int

The fmap from our Functor instance will ignore Left values, but will apply the supplied function to values contained in a Right:

>>> let s = Left "foo" :: Either String Int
>>> let n = Right 3 :: Either String Int
>>> fmap (*2) s
Left "foo"
>>> fmap (*2) n
Right 6

The Monad instance for Either allows us to chain together multiple actions which may fail, and fail overall if any of the individual steps failed. First we'll write a function that can either parse an Int from a Char, or fail.

>>> import Data.Char ( digitToInt, isDigit )
>>> :{
    let parseEither :: Char -> Either String Int
        parseEither c
          | isDigit c = Right (digitToInt c)
          | otherwise = Left "parse error"
>>> :}

The following should work, since both '1' and '2' can be parsed as Ints.

>>> :{
    let parseMultiple :: Either String Int
        parseMultiple = do
          x <- parseEither '1'
          y <- parseEither '2'
          return (x + y)
>>> :}

>>> parseMultiple
Right 3

But the following should fail overall, since the first operation where we attempt to parse 'm' as an Int will fail:

>>> :{
    let parseMultiple :: Either String Int
        parseMultiple = do
          x <- parseEither 'm'
          y <- parseEither '2'
          return (x + y)
>>> :}

>>> parseMultiple
Left "parse error"

Constructors

Left a
Right b

Instances

Bifunctor Either	Since: base-4.8.0.0
Instance details Defined in Data.Bifunctor Methods bimap :: (a -> b) -> (c -> d) -> Either a c -> Either b d # first :: (a -> b) -> Either a c -> Either b c # second :: (b -> c) -> Either a b -> Either a c #
NFData2 Either	Since: deepseq-1.4.3.0
Instance details Defined in Control.DeepSeq Methods liftRnf2 :: (a -> ()) -> (b -> ()) -> Either a b -> () #
Hashable2 Either
Instance details Defined in Data.Hashable.Class Methods liftHashWithSalt2 :: (Int -> a -> Int) -> (Int -> b -> Int) -> Int -> Either a b -> Int #
MonadError e (Either e)
Instance details Defined in Control.Monad.Error.Class Methods throwError :: e -> Either e a # catchError :: Either e a -> (e -> Either e a) -> Either e a #
Monad (Either e)	Since: base-4.4.0.0
Instance details Defined in Data.Either Methods (>>=) :: Either e a -> (a -> Either e b) -> Either e b # (>>) :: Either e a -> Either e b -> Either e b # return :: a -> Either e a # fail :: String -> Either e a #
Functor (Either a)	Since: base-3.0
Instance details Defined in Data.Either Methods fmap :: (a0 -> b) -> Either a a0 -> Either a b # (<$) :: a0 -> Either a b -> Either a a0 #
Applicative (Either e)	Since: base-3.0
Instance details Defined in Data.Either Methods pure :: a -> Either e a # (<>) :: Either e (a -> b) -> Either e a -> Either e b # liftA2 :: (a -> b -> c) -> Either e a -> Either e b -> Either e c # (>) :: Either e a -> Either e b -> Either e b # (<*) :: Either e a -> Either e b -> Either e a #
Foldable (Either a)	Since: base-4.7.0.0
Instance details Defined in Data.Foldable Methods fold :: Monoid m => Either a m -> m # foldMap :: Monoid m => (a0 -> m) -> Either a a0 -> m # foldr :: (a0 -> b -> b) -> b -> Either a a0 -> b # foldr' :: (a0 -> b -> b) -> b -> Either a a0 -> b # foldl :: (b -> a0 -> b) -> b -> Either a a0 -> b # foldl' :: (b -> a0 -> b) -> b -> Either a a0 -> b # foldr1 :: (a0 -> a0 -> a0) -> Either a a0 -> a0 # foldl1 :: (a0 -> a0 -> a0) -> Either a a0 -> a0 # toList :: Either a a0 -> [a0] # null :: Either a a0 -> Bool # length :: Either a a0 -> Int # elem :: Eq a0 => a0 -> Either a a0 -> Bool # maximum :: Ord a0 => Either a a0 -> a0 # minimum :: Ord a0 => Either a a0 -> a0 # sum :: Num a0 => Either a a0 -> a0 # product :: Num a0 => Either a a0 -> a0 #
Traversable (Either a)	Since: base-4.7.0.0
Instance details Defined in Data.Traversable Methods traverse :: Applicative f => (a0 -> f b) -> Either a a0 -> f (Either a b) # sequenceA :: Applicative f => Either a (f a0) -> f (Either a a0) # mapM :: Monad m => (a0 -> m b) -> Either a a0 -> m (Either a b) # sequence :: Monad m => Either a (m a0) -> m (Either a a0) #
NFData a => NFData1 (Either a)	Since: deepseq-1.4.3.0
Instance details Defined in Control.DeepSeq Methods liftRnf :: (a0 -> ()) -> Either a a0 -> () #
e ~ SomeException => MonadThrow (Either e)
Instance details Defined in Control.Monad.Catch Methods throwM :: Exception e0 => e0 -> Either e a #
e ~ SomeException => MonadCatch (Either e)	Since: exceptions-0.8.3
Instance details Defined in Control.Monad.Catch Methods catch :: Exception e0 => Either e a -> (e0 -> Either e a) -> Either e a #
e ~ SomeException => MonadMask (Either e)	Since: exceptions-0.8.3
Instance details Defined in Control.Monad.Catch Methods mask :: ((forall a. Either e a -> Either e a) -> Either e b) -> Either e b # uninterruptibleMask :: ((forall a. Either e a -> Either e a) -> Either e b) -> Either e b # generalBracket :: Either e a -> (a -> ExitCase b -> Either e c) -> (a -> Either e b) -> Either e (b, c) #
Hashable a => Hashable1 (Either a)
Instance details Defined in Data.Hashable.Class Methods liftHashWithSalt :: (Int -> a0 -> Int) -> Int -> Either a a0 -> Int #
Generic1 (Either a :: Type -> Type)
Instance details Defined in GHC.Generics Associated Types type Rep1 (Either a) :: k -> Type # Methods from1 :: Either a a0 -> Rep1 (Either a) a0 # to1 :: Rep1 (Either a) a0 -> Either a a0 #
(Eq a, Eq b) => Eq (Either a b)	Since: base-2.1
Instance details Defined in Data.Either Methods (==) :: Either a b -> Either a b -> Bool # (/=) :: Either a b -> Either a b -> Bool #
(Ord a, Ord b) => Ord (Either a b)	Since: base-2.1
Instance details Defined in Data.Either Methods compare :: Either a b -> Either a b -> Ordering # (<) :: Either a b -> Either a b -> Bool # (<=) :: Either a b -> Either a b -> Bool # (>) :: Either a b -> Either a b -> Bool # (>=) :: Either a b -> Either a b -> Bool # max :: Either a b -> Either a b -> Either a b # min :: Either a b -> Either a b -> Either a b #
(Read a, Read b) => Read (Either a b)	Since: base-3.0
Instance details Defined in Data.Either Methods readsPrec :: Int -> ReadS (Either a b) # readList :: ReadS [Either a b] # readPrec :: ReadPrec (Either a b) # readListPrec :: ReadPrec [Either a b] #
(Show a, Show b) => Show (Either a b)	Since: base-3.0
Instance details Defined in Data.Either Methods showsPrec :: Int -> Either a b -> ShowS # show :: Either a b -> String # showList :: [Either a b] -> ShowS #
Generic (Either a b)
Instance details Defined in GHC.Generics Associated Types type Rep (Either a b) :: Type -> Type # Methods from :: Either a b -> Rep (Either a b) x # to :: Rep (Either a b) x -> Either a b #
Semigroup (Either a b)	Since: base-4.9.0.0
Instance details Defined in Data.Either Methods (<>) :: Either a b -> Either a b -> Either a b # sconcat :: NonEmpty (Either a b) -> Either a b # stimes :: Integral b0 => b0 -> Either a b -> Either a b #
(NFData a, NFData b) => NFData (Either a b)
Instance details Defined in Control.DeepSeq Methods rnf :: Either a b -> () #
(Hashable a, Hashable b) => Hashable (Either a b)
Instance details Defined in Data.Hashable.Class Methods hashWithSalt :: Int -> Either a b -> Int # hash :: Either a b -> Int #
(TypeError (DisallowInstance "Either") :: Constraint) => Container (Either a b)
Instance details Defined in Universum.Container.Class Associated Types type Element (Either a b) :: Type # Methods toList :: Either a b -> [Element (Either a b)] # null :: Either a b -> Bool # foldr :: (Element (Either a b) -> b0 -> b0) -> b0 -> Either a b -> b0 # foldl :: (b0 -> Element (Either a b) -> b0) -> b0 -> Either a b -> b0 # foldl' :: (b0 -> Element (Either a b) -> b0) -> b0 -> Either a b -> b0 # length :: Either a b -> Int # elem :: Element (Either a b) -> Either a b -> Bool # maximum :: Either a b -> Element (Either a b) # minimum :: Either a b -> Element (Either a b) # foldMap :: Monoid m => (Element (Either a b) -> m) -> Either a b -> m # fold :: Either a b -> Element (Either a b) # foldr' :: (Element (Either a b) -> b0 -> b0) -> b0 -> Either a b -> b0 # foldr1 :: (Element (Either a b) -> Element (Either a b) -> Element (Either a b)) -> Either a b -> Element (Either a b) # foldl1 :: (Element (Either a b) -> Element (Either a b) -> Element (Either a b)) -> Either a b -> Element (Either a b) # notElem :: Element (Either a b) -> Either a b -> Bool # all :: (Element (Either a b) -> Bool) -> Either a b -> Bool # any :: (Element (Either a b) -> Bool) -> Either a b -> Bool # and :: Either a b -> Bool # or :: Either a b -> Bool # find :: (Element (Either a b) -> Bool) -> Either a b -> Maybe (Element (Either a b)) # safeHead :: Either a b -> Maybe (Element (Either a b)) #
(a ~ a', b ~ b') => Each (Either a a') (Either b b') a b	Since: microlens-0.4.11
Instance details Defined in Lens.Micro.Internal Methods each :: Traversal (Either a a') (Either b b') a b #
type Rep1 (Either a :: Type -> Type)	Since: base-4.6.0.0
Instance details Defined in GHC.Generics type Rep1 (Either a :: Type -> Type) = D1 (MetaData "Either" "Data.Either" "base" False) (C1 (MetaCons "Left" PrefixI False) (S1 (MetaSel (Nothing :: Maybe Symbol) NoSourceUnpackedness NoSourceStrictness DecidedLazy) (Rec0 a)) :+: C1 (MetaCons "Right" PrefixI False) (S1 (MetaSel (Nothing :: Maybe Symbol) NoSourceUnpackedness NoSourceStrictness DecidedLazy) Par1))
type Rep (Either a b)	Since: base-4.6.0.0
Instance details Defined in GHC.Generics type Rep (Either a b) = D1 (MetaData "Either" "Data.Either" "base" False) (C1 (MetaCons "Left" PrefixI False) (S1 (MetaSel (Nothing :: Maybe Symbol) NoSourceUnpackedness NoSourceStrictness DecidedLazy) (Rec0 a)) :+: C1 (MetaCons "Right" PrefixI False) (S1 (MetaSel (Nothing :: Maybe Symbol) NoSourceUnpackedness NoSourceStrictness DecidedLazy) (Rec0 b)))
type Element (Either a b)
Instance details Defined in Universum.Container.Class type Element (Either a b) = ElementDefault (Either a b)

data Constraint #

The kind of constraints, like Show a

type family CmpNat (a :: Nat) (b :: Nat) :: Ordering where ... #

Comparison of type-level naturals, as a function.

Since: base-4.7.0.0

class a ~R# b => Coercible (a :: k0) (b :: k0) #

Coercible is a two-parameter class that has instances for types a and b if the compiler can infer that they have the same representation. This class does not have regular instances; instead they are created on-the-fly during type-checking. Trying to manually declare an instance of Coercible is an error.

Nevertheless one can pretend that the following three kinds of instances exist. First, as a trivial base-case:

instance Coercible a a

Furthermore, for every type constructor there is an instance that allows to coerce under the type constructor. For example, let D be a prototypical type constructor (data or newtype) with three type arguments, which have roles nominal, representational resp. phantom. Then there is an instance of the form

instance Coercible b b' => Coercible (D a b c) (D a b' c')

Note that the nominal type arguments are equal, the representational type arguments can differ, but need to have a Coercible instance themself, and the phantom type arguments can be changed arbitrarily.

The third kind of instance exists for every newtype NT = MkNT T and comes in two variants, namely

instance Coercible a T => Coercible a NT

instance Coercible T b => Coercible NT b

This instance is only usable if the constructor MkNT is in scope.

If, as a library author of a type constructor like Set a, you want to prevent a user of your module to write coerce :: Set T -> Set NT, you need to set the role of Set's type parameter to nominal, by writing

type role Set nominal

For more details about this feature, please refer to Safe Coercions by Joachim Breitner, Richard A. Eisenberg, Simon Peyton Jones and Stephanie Weirich.

Since: ghc-prim-4.7.0.0

data CallStack #

CallStacks are a lightweight method of obtaining a partial call-stack at any point in the program.

A function can request its call-site with the HasCallStack constraint. For example, we can define

putStrLnWithCallStack :: HasCallStack => String -> IO ()

as a variant of putStrLn that will get its call-site and print it, along with the string given as argument. We can access the call-stack inside putStrLnWithCallStack with callStack.

putStrLnWithCallStack :: HasCallStack => String -> IO ()
putStrLnWithCallStack msg = do
  putStrLn msg
  putStrLn (prettyCallStack callStack)

Thus, if we call putStrLnWithCallStack we will get a formatted call-stack alongside our string.

>>> putStrLnWithCallStack "hello"
hello
CallStack (from HasCallStack):
  putStrLnWithCallStack, called at <interactive>:2:1 in interactive:Ghci1

GHC solves HasCallStack constraints in three steps:

If there is a CallStack in scope -- i.e. the enclosing function has a HasCallStack constraint -- GHC will append the new call-site to the existing CallStack.
If there is no CallStack in scope -- e.g. in the GHCi session above -- and the enclosing definition does not have an explicit type signature, GHC will infer a HasCallStack constraint for the enclosing definition (subject to the monomorphism restriction).
If there is no CallStack in scope and the enclosing definition has an explicit type signature, GHC will solve the HasCallStack constraint for the singleton CallStack containing just the current call-site.

CallStacks do not interact with the RTS and do not require compilation with -prof. On the other hand, as they are built up explicitly via the HasCallStack constraints, they will generally not contain as much information as the simulated call-stacks maintained by the RTS.

A CallStack is a [(String, SrcLoc)]. The String is the name of function that was called, the SrcLoc is the call-site. The list is ordered with the most recently called function at the head.

NOTE: The intrepid user may notice that HasCallStack is just an alias for an implicit parameter ?callStack :: CallStack. This is an implementation detail and should not be considered part of the CallStack API, we may decide to change the implementation in the future.

Since: base-4.8.1.0

Instances

IsList CallStack	Be aware that 'fromList . toList = id' only for unfrozen `CallStack`s, since `toList` removes frozenness information. Since: base-4.9.0.0
Instance details Defined in GHC.Exts Associated Types type Item CallStack :: Type # Methods fromList :: [Item CallStack] -> CallStack # fromListN :: Int -> [Item CallStack] -> CallStack # toList :: CallStack -> [Item CallStack] #
Show CallStack	Since: base-4.9.0.0
Instance details Defined in GHC.Show Methods showsPrec :: Int -> CallStack -> ShowS # show :: CallStack -> String # showList :: [CallStack] -> ShowS #
NFData CallStack	Since: deepseq-1.4.2.0
Instance details Defined in Control.DeepSeq Methods rnf :: CallStack -> () #
type Item CallStack
Instance details Defined in GHC.Exts type Item CallStack = (String, SrcLoc)

data Handle #

Haskell defines operations to read and write characters from and to files, represented by values of type Handle. Each value of this type is a handle: a record used by the Haskell run-time system to manage I/O with file system objects. A handle has at least the following properties:

whether it manages input or output or both;
whether it is open, closed or semi-closed;
whether the object is seekable;
whether buffering is disabled, or enabled on a line or block basis;
a buffer (whose length may be zero).

Most handles will also have a current I/O position indicating where the next input or output operation will occur. A handle is readable if it manages only input or both input and output; likewise, it is writable if it manages only output or both input and output. A handle is open when first allocated. Once it is closed it can no longer be used for either input or output, though an implementation cannot re-use its storage while references remain to it. Handles are in the Show and Eq classes. The string produced by showing a handle is system dependent; it should include enough information to identify the handle for debugging. A handle is equal according to == only to itself; no attempt is made to compare the internal state of different handles for equality.

Instances

Eq Handle	Since: base-4.1.0.0
Instance details Defined in GHC.IO.Handle.Types Methods (==) :: Handle -> Handle -> Bool # (/=) :: Handle -> Handle -> Bool #
Show Handle	Since: base-4.1.0.0
Instance details Defined in GHC.IO.Handle.Types Methods showsPrec :: Int -> Handle -> ShowS # show :: Handle -> String # showList :: [Handle] -> ShowS #

integralEnumFromThenTo :: Integral a => a -> a -> a -> [a] #

integralEnumFromTo :: Integral a => a -> a -> [a] #

integralEnumFromThen :: (Integral a, Bounded a) => a -> a -> [a] #

integralEnumFrom :: (Integral a, Bounded a) => a -> [a] #

gcdWord' :: Word -> Word -> Word #

gcdInt' :: Int -> Int -> Int #

(^^%^^) :: Integral a => Rational -> a -> Rational #

(^%^) :: Integral a => Rational -> a -> Rational #

numericEnumFromThenTo :: (Ord a, Fractional a) => a -> a -> a -> [a] #

numericEnumFromTo :: (Ord a, Fractional a) => a -> a -> [a] #

numericEnumFromThen :: Fractional a => a -> a -> [a] #

numericEnumFrom :: Fractional a => a -> [a] #

notANumber :: Rational #

infinity :: Rational #

ratioPrec1 :: Int #

ratioPrec :: Int #

underflowError :: a #

overflowError :: a #

ratioZeroDenominatorError :: a #

divZeroError :: a #

reduce :: Integral a => a -> a -> Ratio a #

reduce is a subsidiary function used only in this module. It normalises a ratio by dividing both numerator and denominator by their greatest common divisor.

boundedEnumFromThen :: (Enum a, Bounded a) => a -> a -> [a] #

boundedEnumFrom :: (Enum a, Bounded a) => a -> [a] #

maxInt :: Int #

minInt :: Int #

newtype Compose (f :: k -> Type) (g :: k1 -> k) (a :: k1) :: forall k k1. (k -> Type) -> (k1 -> k) -> k1 -> Type infixr 9 #

Right-to-left composition of functors. The composition of applicative functors is always applicative, but the composition of monads is not always a monad.

Constructors

Compose infixr 9
Fields getCompose :: f (g a)

Instances

Functor f => Generic1 (Compose f g :: k -> Type)
Instance details Defined in Data.Functor.Compose Associated Types type Rep1 (Compose f g) :: k -> Type # Methods from1 :: Compose f g a -> Rep1 (Compose f g) a # to1 :: Rep1 (Compose f g) a -> Compose f g a #
(Functor f, Functor g) => Functor (Compose f g)	Since: base-4.9.0.0
Instance details Defined in Data.Functor.Compose Methods fmap :: (a -> b) -> Compose f g a -> Compose f g b # (<$) :: a -> Compose f g b -> Compose f g a #
(Applicative f, Applicative g) => Applicative (Compose f g)	Since: base-4.9.0.0
Instance details Defined in Data.Functor.Compose Methods pure :: a -> Compose f g a # (<>) :: Compose f g (a -> b) -> Compose f g a -> Compose f g b # liftA2 :: (a -> b -> c) -> Compose f g a -> Compose f g b -> Compose f g c # (>) :: Compose f g a -> Compose f g b -> Compose f g b # (<*) :: Compose f g a -> Compose f g b -> Compose f g a #
(Foldable f, Foldable g) => Foldable (Compose f g)	Since: base-4.9.0.0
Instance details Defined in Data.Functor.Compose Methods fold :: Monoid m => Compose f g m -> m # foldMap :: Monoid m => (a -> m) -> Compose f g a -> m # foldr :: (a -> b -> b) -> b -> Compose f g a -> b # foldr' :: (a -> b -> b) -> b -> Compose f g a -> b # foldl :: (b -> a -> b) -> b -> Compose f g a -> b # foldl' :: (b -> a -> b) -> b -> Compose f g a -> b # foldr1 :: (a -> a -> a) -> Compose f g a -> a # foldl1 :: (a -> a -> a) -> Compose f g a -> a # toList :: Compose f g a -> [a] # null :: Compose f g a -> Bool # length :: Compose f g a -> Int # elem :: Eq a => a -> Compose f g a -> Bool # maximum :: Ord a => Compose f g a -> a # minimum :: Ord a => Compose f g a -> a # sum :: Num a => Compose f g a -> a # product :: Num a => Compose f g a -> a #
(Traversable f, Traversable g) => Traversable (Compose f g)	Since: base-4.9.0.0
Instance details Defined in Data.Functor.Compose Methods traverse :: Applicative f0 => (a -> f0 b) -> Compose f g a -> f0 (Compose f g b) # sequenceA :: Applicative f0 => Compose f g (f0 a) -> f0 (Compose f g a) # mapM :: Monad m => (a -> m b) -> Compose f g a -> m (Compose f g b) # sequence :: Monad m => Compose f g (m a) -> m (Compose f g a) #
(Eq1 f, Eq1 g) => Eq1 (Compose f g)	Since: base-4.9.0.0
Instance details Defined in Data.Functor.Compose Methods liftEq :: (a -> b -> Bool) -> Compose f g a -> Compose f g b -> Bool #
(Ord1 f, Ord1 g) => Ord1 (Compose f g)	Since: base-4.9.0.0
Instance details Defined in Data.Functor.Compose Methods liftCompare :: (a -> b -> Ordering) -> Compose f g a -> Compose f g b -> Ordering #
(Read1 f, Read1 g) => Read1 (Compose f g)	Since: base-4.9.0.0
Instance details Defined in Data.Functor.Compose Methods liftReadsPrec :: (Int -> ReadS a) -> ReadS [a] -> Int -> ReadS (Compose f g a) # liftReadList :: (Int -> ReadS a) -> ReadS [a] -> ReadS [Compose f g a] # liftReadPrec :: ReadPrec a -> ReadPrec [a] -> ReadPrec (Compose f g a) # liftReadListPrec :: ReadPrec a -> ReadPrec [a] -> ReadPrec [Compose f g a] #
(Show1 f, Show1 g) => Show1 (Compose f g)	Since: base-4.9.0.0
Instance details Defined in Data.Functor.Compose Methods liftShowsPrec :: (Int -> a -> ShowS) -> ([a] -> ShowS) -> Int -> Compose f g a -> ShowS # liftShowList :: (Int -> a -> ShowS) -> ([a] -> ShowS) -> [Compose f g a] -> ShowS #
(Alternative f, Applicative g) => Alternative (Compose f g)	Since: base-4.9.0.0
Instance details Defined in Data.Functor.Compose Methods empty :: Compose f g a # (<\|>) :: Compose f g a -> Compose f g a -> Compose f g a # some :: Compose f g a -> Compose f g [a] # many :: Compose f g a -> Compose f g [a] #
(NFData1 f, NFData1 g) => NFData1 (Compose f g)	Since: deepseq-1.4.3.0
Instance details Defined in Control.DeepSeq Methods liftRnf :: (a -> ()) -> Compose f g a -> () #
(Hashable1 f, Hashable1 g) => Hashable1 (Compose f g)
Instance details Defined in Data.Hashable.Class Methods liftHashWithSalt :: (Int -> a -> Int) -> Int -> Compose f g a -> Int #
(Eq1 f, Eq1 g, Eq a) => Eq (Compose f g a)	Since: base-4.9.0.0
Instance details Defined in Data.Functor.Compose Methods (==) :: Compose f g a -> Compose f g a -> Bool # (/=) :: Compose f g a -> Compose f g a -> Bool #
(Typeable a, Typeable f, Typeable g, Typeable k1, Typeable k2, Data (f (g a))) => Data (Compose f g a)	Since: base-4.9.0.0
Instance details Defined in Data.Functor.Compose Methods gfoldl :: (forall d b. Data d => c (d -> b) -> d -> c b) -> (forall g0. g0 -> c g0) -> Compose f g a -> c (Compose f g a) # gunfold :: (forall b r. Data b => c (b -> r) -> c r) -> (forall r. r -> c r) -> Constr -> c (Compose f g a) # toConstr :: Compose f g a -> Constr # dataTypeOf :: Compose f g a -> DataType # dataCast1 :: Typeable t => (forall d. Data d => c (t d)) -> Maybe (c (Compose f g a)) # dataCast2 :: Typeable t => (forall d e. (Data d, Data e) => c (t d e)) -> Maybe (c (Compose f g a)) # gmapT :: (forall b. Data b => b -> b) -> Compose f g a -> Compose f g a # gmapQl :: (r -> r' -> r) -> r -> (forall d. Data d => d -> r') -> Compose f g a -> r # gmapQr :: (r' -> r -> r) -> r -> (forall d. Data d => d -> r') -> Compose f g a -> r # gmapQ :: (forall d. Data d => d -> u) -> Compose f g a -> [u] # gmapQi :: Int -> (forall d. Data d => d -> u) -> Compose f g a -> u # gmapM :: Monad m => (forall d. Data d => d -> m d) -> Compose f g a -> m (Compose f g a) # gmapMp :: MonadPlus m => (forall d. Data d => d -> m d) -> Compose f g a -> m (Compose f g a) # gmapMo :: MonadPlus m => (forall d. Data d => d -> m d) -> Compose f g a -> m (Compose f g a) #
(Ord1 f, Ord1 g, Ord a) => Ord (Compose f g a)	Since: base-4.9.0.0
Instance details Defined in Data.Functor.Compose Methods compare :: Compose f g a -> Compose f g a -> Ordering # (<) :: Compose f g a -> Compose f g a -> Bool # (<=) :: Compose f g a -> Compose f g a -> Bool # (>) :: Compose f g a -> Compose f g a -> Bool # (>=) :: Compose f g a -> Compose f g a -> Bool # max :: Compose f g a -> Compose f g a -> Compose f g a # min :: Compose f g a -> Compose f g a -> Compose f g a #
(Read1 f, Read1 g, Read a) => Read (Compose f g a)	Since: base-4.9.0.0
Instance details Defined in Data.Functor.Compose Methods readsPrec :: Int -> ReadS (Compose f g a) # readList :: ReadS [Compose f g a] # readPrec :: ReadPrec (Compose f g a) # readListPrec :: ReadPrec [Compose f g a] #
(Show1 f, Show1 g, Show a) => Show (Compose f g a)	Since: base-4.9.0.0
Instance details Defined in Data.Functor.Compose Methods showsPrec :: Int -> Compose f g a -> ShowS # show :: Compose f g a -> String # showList :: [Compose f g a] -> ShowS #
Generic (Compose f g a)
Instance details Defined in Data.Functor.Compose Associated Types type Rep (Compose f g a) :: Type -> Type # Methods from :: Compose f g a -> Rep (Compose f g a) x # to :: Rep (Compose f g a) x -> Compose f g a #
(NFData1 f, NFData1 g, NFData a) => NFData (Compose f g a)	Since: deepseq-1.4.3.0
Instance details Defined in Control.DeepSeq Methods rnf :: Compose f g a -> () #
(Hashable1 f, Hashable1 g, Hashable a) => Hashable (Compose f g a)	In general, `hash (Compose x) ≠ hash x`. However, `hashWithSalt` satisfies its variant of this equivalence.
Instance details Defined in Data.Hashable.Class Methods hashWithSalt :: Int -> Compose f g a -> Int # hash :: Compose f g a -> Int #
type Rep1 (Compose f g :: k -> Type)	Since: base-4.9.0.0
Instance details Defined in Data.Functor.Compose type Rep1 (Compose f g :: k -> Type) = D1 (MetaData "Compose" "Data.Functor.Compose" "base" True) (C1 (MetaCons "Compose" PrefixI True) (S1 (MetaSel (Just "getCompose") NoSourceUnpackedness NoSourceStrictness DecidedLazy) (f :.: Rec1 g)))
type Rep (Compose f g a)	Since: base-4.9.0.0
Instance details Defined in Data.Functor.Compose type Rep (Compose f g a) = D1 (MetaData "Compose" "Data.Functor.Compose" "base" True) (C1 (MetaCons "Compose" PrefixI True) (S1 (MetaSel (Just "getCompose") NoSourceUnpackedness NoSourceStrictness DecidedLazy) (Rec0 (f (g a)))))

vacuous :: Functor f => f Void -> f a #

If Void is uninhabited then any Functor that holds only values of type Void is holding no values.

Since: base-4.8.0.0

absurd :: Void -> a #

Since Void values logically don't exist, this witnesses the logical reasoning tool of "ex falso quodlibet".

>>> let x :: Either Void Int; x = Right 5
>>> :{
case x of
    Right r -> r
    Left l  -> absurd l
:}
5

Since: base-4.8.0.0

data Void #

Uninhabited data type

Since: base-4.8.0.0

Instances

Eq Void	Since: base-4.8.0.0
Instance details Defined in Data.Void Methods (==) :: Void -> Void -> Bool # (/=) :: Void -> Void -> Bool #
Data Void	Since: base-4.8.0.0
Instance details Defined in Data.Void Methods gfoldl :: (forall d b. Data d => c (d -> b) -> d -> c b) -> (forall g. g -> c g) -> Void -> c Void # gunfold :: (forall b r. Data b => c (b -> r) -> c r) -> (forall r. r -> c r) -> Constr -> c Void # toConstr :: Void -> Constr # dataTypeOf :: Void -> DataType # dataCast1 :: Typeable t => (forall d. Data d => c (t d)) -> Maybe (c Void) # dataCast2 :: Typeable t => (forall d e. (Data d, Data e) => c (t d e)) -> Maybe (c Void) # gmapT :: (forall b. Data b => b -> b) -> Void -> Void # gmapQl :: (r -> r' -> r) -> r -> (forall d. Data d => d -> r') -> Void -> r # gmapQr :: (r' -> r -> r) -> r -> (forall d. Data d => d -> r') -> Void -> r # gmapQ :: (forall d. Data d => d -> u) -> Void -> [u] # gmapQi :: Int -> (forall d. Data d => d -> u) -> Void -> u # gmapM :: Monad m => (forall d. Data d => d -> m d) -> Void -> m Void # gmapMp :: MonadPlus m => (forall d. Data d => d -> m d) -> Void -> m Void # gmapMo :: MonadPlus m => (forall d. Data d => d -> m d) -> Void -> m Void #
Ord Void	Since: base-4.8.0.0
Instance details Defined in Data.Void Methods compare :: Void -> Void -> Ordering # (<) :: Void -> Void -> Bool # (<=) :: Void -> Void -> Bool # (>) :: Void -> Void -> Bool # (>=) :: Void -> Void -> Bool # max :: Void -> Void -> Void # min :: Void -> Void -> Void #
Read Void	Reading a `Void` value is always a parse error, considering `Void` as a data type with no constructors. Since: base-4.8.0.0
Instance details Defined in Data.Void Methods readsPrec :: Int -> ReadS Void # readList :: ReadS [Void] # readPrec :: ReadPrec Void # readListPrec :: ReadPrec [Void] #
Show Void	Since: base-4.8.0.0
Instance details Defined in Data.Void Methods showsPrec :: Int -> Void -> ShowS # show :: Void -> String # showList :: [Void] -> ShowS #
Ix Void	Since: base-4.8.0.0
Instance details Defined in Data.Void Methods range :: (Void, Void) -> [Void] # index :: (Void, Void) -> Void -> Int # unsafeIndex :: (Void, Void) -> Void -> Int inRange :: (Void, Void) -> Void -> Bool # rangeSize :: (Void, Void) -> Int # unsafeRangeSize :: (Void, Void) -> Int
Generic Void
Instance details Defined in Data.Void Associated Types type Rep Void :: Type -> Type # Methods from :: Void -> Rep Void x # to :: Rep Void x -> Void #
Semigroup Void	Since: base-4.9.0.0
Instance details Defined in Data.Void Methods (<>) :: Void -> Void -> Void # sconcat :: NonEmpty Void -> Void # stimes :: Integral b => b -> Void -> Void #
Exception Void	Since: base-4.8.0.0
Instance details Defined in Data.Void Methods toException :: Void -> SomeException # fromException :: SomeException -> Maybe Void # displayException :: Void -> String #
NFData Void	Defined as `rnf = absurd`. Since: deepseq-1.4.0.0
Instance details Defined in Control.DeepSeq Methods rnf :: Void -> () #
Hashable Void
Instance details Defined in Data.Hashable.Class Methods hashWithSalt :: Int -> Void -> Int # hash :: Void -> Int #
type Rep Void	Since: base-4.8.0.0
Instance details Defined in Data.Void type Rep Void = D1 (MetaData "Void" "Data.Void" "base" False) (V1 :: Type -> Type)

mtimesDefault :: (Integral b, Monoid a) => b -> a -> a #

Repeat a value n times.

mtimesDefault n a = a <> a <> ... <> a  -- using <> (n-1) times

Implemented using stimes and mempty.

This is a suitable definition for an mtimes member of Monoid.

cycle1 :: Semigroup m => m -> m #

A generalization of cycle to an arbitrary Semigroup. May fail to terminate for some values in some semigroups.

data WrappedMonoid m #

Provide a Semigroup for an arbitrary Monoid.

NOTE: This is not needed anymore since Semigroup became a superclass of Monoid in base-4.11 and this newtype be deprecated at some point in the future.

Instances

NFData1 WrappedMonoid	Since: deepseq-1.4.3.0
Instance details Defined in Control.DeepSeq Methods liftRnf :: (a -> ()) -> WrappedMonoid a -> () #
Bounded m => Bounded (WrappedMonoid m)	Since: base-4.9.0.0
Instance details Defined in Data.Semigroup Methods minBound :: WrappedMonoid m # maxBound :: WrappedMonoid m #
Enum a => Enum (WrappedMonoid a)	Since: base-4.9.0.0
Instance details Defined in Data.Semigroup Methods succ :: WrappedMonoid a -> WrappedMonoid a # pred :: WrappedMonoid a -> WrappedMonoid a # toEnum :: Int -> WrappedMonoid a # fromEnum :: WrappedMonoid a -> Int # enumFrom :: WrappedMonoid a -> [WrappedMonoid a] # enumFromThen :: WrappedMonoid a -> WrappedMonoid a -> [WrappedMonoid a] # enumFromTo :: WrappedMonoid a -> WrappedMonoid a -> [WrappedMonoid a] # enumFromThenTo :: WrappedMonoid a -> WrappedMonoid a -> WrappedMonoid a -> [WrappedMonoid a] #
Eq m => Eq (WrappedMonoid m)	Since: base-4.9.0.0
Instance details Defined in Data.Semigroup Methods (==) :: WrappedMonoid m -> WrappedMonoid m -> Bool # (/=) :: WrappedMonoid m -> WrappedMonoid m -> Bool #
Data m => Data (WrappedMonoid m)	Since: base-4.9.0.0
Instance details Defined in Data.Semigroup Methods gfoldl :: (forall d b. Data d => c (d -> b) -> d -> c b) -> (forall g. g -> c g) -> WrappedMonoid m -> c (WrappedMonoid m) # gunfold :: (forall b r. Data b => c (b -> r) -> c r) -> (forall r. r -> c r) -> Constr -> c (WrappedMonoid m) # toConstr :: WrappedMonoid m -> Constr # dataTypeOf :: WrappedMonoid m -> DataType # dataCast1 :: Typeable t => (forall d. Data d => c (t d)) -> Maybe (c (WrappedMonoid m)) # dataCast2 :: Typeable t => (forall d e. (Data d, Data e) => c (t d e)) -> Maybe (c (WrappedMonoid m)) # gmapT :: (forall b. Data b => b -> b) -> WrappedMonoid m -> WrappedMonoid m # gmapQl :: (r -> r' -> r) -> r -> (forall d. Data d => d -> r') -> WrappedMonoid m -> r # gmapQr :: (r' -> r -> r) -> r -> (forall d. Data d => d -> r') -> WrappedMonoid m -> r # gmapQ :: (forall d. Data d => d -> u) -> WrappedMonoid m -> [u] # gmapQi :: Int -> (forall d. Data d => d -> u) -> WrappedMonoid m -> u # gmapM :: Monad m0 => (forall d. Data d => d -> m0 d) -> WrappedMonoid m -> m0 (WrappedMonoid m) # gmapMp :: MonadPlus m0 => (forall d. Data d => d -> m0 d) -> WrappedMonoid m -> m0 (WrappedMonoid m) # gmapMo :: MonadPlus m0 => (forall d. Data d => d -> m0 d) -> WrappedMonoid m -> m0 (WrappedMonoid m) #
Ord m => Ord (WrappedMonoid m)	Since: base-4.9.0.0
Instance details Defined in Data.Semigroup Methods compare :: WrappedMonoid m -> WrappedMonoid m -> Ordering # (<) :: WrappedMonoid m -> WrappedMonoid m -> Bool # (<=) :: WrappedMonoid m -> WrappedMonoid m -> Bool # (>) :: WrappedMonoid m -> WrappedMonoid m -> Bool # (>=) :: WrappedMonoid m -> WrappedMonoid m -> Bool # max :: WrappedMonoid m -> WrappedMonoid m -> WrappedMonoid m # min :: WrappedMonoid m -> WrappedMonoid m -> WrappedMonoid m #
Read m => Read (WrappedMonoid m)	Since: base-4.9.0.0
Instance details Defined in Data.Semigroup Methods readsPrec :: Int -> ReadS (WrappedMonoid m) # readList :: ReadS [WrappedMonoid m] # readPrec :: ReadPrec (WrappedMonoid m) # readListPrec :: ReadPrec [WrappedMonoid m] #
Show m => Show (WrappedMonoid m)	Since: base-4.9.0.0
Instance details Defined in Data.Semigroup Methods showsPrec :: Int -> WrappedMonoid m -> ShowS # show :: WrappedMonoid m -> String # showList :: [WrappedMonoid m] -> ShowS #
Generic (WrappedMonoid m)
Instance details Defined in Data.Semigroup Associated Types type Rep (WrappedMonoid m) :: Type -> Type # Methods from :: WrappedMonoid m -> Rep (WrappedMonoid m) x # to :: Rep (WrappedMonoid m) x -> WrappedMonoid m #
Monoid m => Semigroup (WrappedMonoid m)	Since: base-4.9.0.0
Instance details Defined in Data.Semigroup Methods (<>) :: WrappedMonoid m -> WrappedMonoid m -> WrappedMonoid m # sconcat :: NonEmpty (WrappedMonoid m) -> WrappedMonoid m # stimes :: Integral b => b -> WrappedMonoid m -> WrappedMonoid m #
Monoid m => Monoid (WrappedMonoid m)	Since: base-4.9.0.0
Instance details Defined in Data.Semigroup Methods mempty :: WrappedMonoid m # mappend :: WrappedMonoid m -> WrappedMonoid m -> WrappedMonoid m # mconcat :: [WrappedMonoid m] -> WrappedMonoid m #
NFData m => NFData (WrappedMonoid m)	Since: deepseq-1.4.2.0
Instance details Defined in Control.DeepSeq Methods rnf :: WrappedMonoid m -> () #
Hashable a => Hashable (WrappedMonoid a)
Instance details Defined in Data.Hashable.Class Methods hashWithSalt :: Int -> WrappedMonoid a -> Int # hash :: WrappedMonoid a -> Int #
Generic1 WrappedMonoid
Instance details Defined in Data.Semigroup Associated Types type Rep1 WrappedMonoid :: k -> Type # Methods from1 :: WrappedMonoid a -> Rep1 WrappedMonoid a # to1 :: Rep1 WrappedMonoid a -> WrappedMonoid a #
type Rep (WrappedMonoid m)	Since: base-4.9.0.0
Instance details Defined in Data.Semigroup type Rep (WrappedMonoid m) = D1 (MetaData "WrappedMonoid" "Data.Semigroup" "base" True) (C1 (MetaCons "WrapMonoid" PrefixI True) (S1 (MetaSel (Just "unwrapMonoid") NoSourceUnpackedness NoSourceStrictness DecidedLazy) (Rec0 m)))
type Rep1 WrappedMonoid	Since: base-4.9.0.0
Instance details Defined in Data.Semigroup type Rep1 WrappedMonoid = D1 (MetaData "WrappedMonoid" "Data.Semigroup" "base" True) (C1 (MetaCons "WrapMonoid" PrefixI True) (S1 (MetaSel (Just "unwrapMonoid") NoSourceUnpackedness NoSourceStrictness DecidedLazy) Par1))

newtype Option a #

Option is effectively Maybe with a better instance of Monoid, built off of an underlying Semigroup instead of an underlying Monoid.

Ideally, this type would not exist at all and we would just fix the Monoid instance of Maybe.

In GHC 8.4 and higher, the Monoid instance for Maybe has been corrected to lift a Semigroup instance instead of a Monoid instance. Consequently, this type is no longer useful. It will be marked deprecated in GHC 8.8 and removed in GHC 8.10.

Constructors

Option
Fields getOption :: Maybe a

Instances

Monad Option	Since: base-4.9.0.0
Instance details Defined in Data.Semigroup Methods (>>=) :: Option a -> (a -> Option b) -> Option b # (>>) :: Option a -> Option b -> Option b # return :: a -> Option a # fail :: String -> Option a #
Functor Option	Since: base-4.9.0.0
Instance details Defined in Data.Semigroup Methods fmap :: (a -> b) -> Option a -> Option b # (<$) :: a -> Option b -> Option a #
MonadFix Option	Since: base-4.9.0.0
Instance details Defined in Data.Semigroup Methods mfix :: (a -> Option a) -> Option a #
Applicative Option	Since: base-4.9.0.0
Instance details Defined in Data.Semigroup Methods pure :: a -> Option a # (<>) :: Option (a -> b) -> Option a -> Option b # liftA2 :: (a -> b -> c) -> Option a -> Option b -> Option c # (>) :: Option a -> Option b -> Option b # (<*) :: Option a -> Option b -> Option a #
Foldable Option	Since: base-4.9.0.0
Instance details Defined in Data.Semigroup Methods fold :: Monoid m => Option m -> m # foldMap :: Monoid m => (a -> m) -> Option a -> m # foldr :: (a -> b -> b) -> b -> Option a -> b # foldr' :: (a -> b -> b) -> b -> Option a -> b # foldl :: (b -> a -> b) -> b -> Option a -> b # foldl' :: (b -> a -> b) -> b -> Option a -> b # foldr1 :: (a -> a -> a) -> Option a -> a # foldl1 :: (a -> a -> a) -> Option a -> a # toList :: Option a -> [a] # null :: Option a -> Bool # length :: Option a -> Int # elem :: Eq a => a -> Option a -> Bool # maximum :: Ord a => Option a -> a # minimum :: Ord a => Option a -> a # sum :: Num a => Option a -> a # product :: Num a => Option a -> a #
Traversable Option	Since: base-4.9.0.0
Instance details Defined in Data.Semigroup Methods traverse :: Applicative f => (a -> f b) -> Option a -> f (Option b) # sequenceA :: Applicative f => Option (f a) -> f (Option a) # mapM :: Monad m => (a -> m b) -> Option a -> m (Option b) # sequence :: Monad m => Option (m a) -> m (Option a) #
Alternative Option	Since: base-4.9.0.0
Instance details Defined in Data.Semigroup Methods empty :: Option a # (<\|>) :: Option a -> Option a -> Option a # some :: Option a -> Option [a] # many :: Option a -> Option [a] #
MonadPlus Option	Since: base-4.9.0.0
Instance details Defined in Data.Semigroup Methods mzero :: Option a # mplus :: Option a -> Option a -> Option a #
NFData1 Option	Since: deepseq-1.4.3.0
Instance details Defined in Control.DeepSeq Methods liftRnf :: (a -> ()) -> Option a -> () #
Eq a => Eq (Option a)	Since: base-4.9.0.0
Instance details Defined in Data.Semigroup Methods (==) :: Option a -> Option a -> Bool # (/=) :: Option a -> Option a -> Bool #
Data a => Data (Option a)	Since: base-4.9.0.0
Instance details Defined in Data.Semigroup Methods gfoldl :: (forall d b. Data d => c (d -> b) -> d -> c b) -> (forall g. g -> c g) -> Option a -> c (Option a) # gunfold :: (forall b r. Data b => c (b -> r) -> c r) -> (forall r. r -> c r) -> Constr -> c (Option a) # toConstr :: Option a -> Constr # dataTypeOf :: Option a -> DataType # dataCast1 :: Typeable t => (forall d. Data d => c (t d)) -> Maybe (c (Option a)) # dataCast2 :: Typeable t => (forall d e. (Data d, Data e) => c (t d e)) -> Maybe (c (Option a)) # gmapT :: (forall b. Data b => b -> b) -> Option a -> Option a # gmapQl :: (r -> r' -> r) -> r -> (forall d. Data d => d -> r') -> Option a -> r # gmapQr :: (r' -> r -> r) -> r -> (forall d. Data d => d -> r') -> Option a -> r # gmapQ :: (forall d. Data d => d -> u) -> Option a -> [u] # gmapQi :: Int -> (forall d. Data d => d -> u) -> Option a -> u # gmapM :: Monad m => (forall d. Data d => d -> m d) -> Option a -> m (Option a) # gmapMp :: MonadPlus m => (forall d. Data d => d -> m d) -> Option a -> m (Option a) # gmapMo :: MonadPlus m => (forall d. Data d => d -> m d) -> Option a -> m (Option a) #
Ord a => Ord (Option a)	Since: base-4.9.0.0
Instance details Defined in Data.Semigroup Methods compare :: Option a -> Option a -> Ordering # (<) :: Option a -> Option a -> Bool # (<=) :: Option a -> Option a -> Bool # (>) :: Option a -> Option a -> Bool # (>=) :: Option a -> Option a -> Bool # max :: Option a -> Option a -> Option a # min :: Option a -> Option a -> Option a #
Read a => Read (Option a)	Since: base-4.9.0.0
Instance details Defined in Data.Semigroup Methods readsPrec :: Int -> ReadS (Option a) # readList :: ReadS [Option a] # readPrec :: ReadPrec (Option a) # readListPrec :: ReadPrec [Option a] #
Show a => Show (Option a)	Since: base-4.9.0.0
Instance details Defined in Data.Semigroup Methods showsPrec :: Int -> Option a -> ShowS # show :: Option a -> String # showList :: [Option a] -> ShowS #
Generic (Option a)
Instance details Defined in Data.Semigroup Associated Types type Rep (Option a) :: Type -> Type # Methods from :: Option a -> Rep (Option a) x # to :: Rep (Option a) x -> Option a #
Semigroup a => Semigroup (Option a)	Since: base-4.9.0.0
Instance details Defined in Data.Semigroup Methods (<>) :: Option a -> Option a -> Option a # sconcat :: NonEmpty (Option a) -> Option a # stimes :: Integral b => b -> Option a -> Option a #
Semigroup a => Monoid (Option a)	Since: base-4.9.0.0
Instance details Defined in Data.Semigroup Methods mempty :: Option a # mappend :: Option a -> Option a -> Option a # mconcat :: [Option a] -> Option a #
NFData a => NFData (Option a)	Since: deepseq-1.4.2.0
Instance details Defined in Control.DeepSeq Methods rnf :: Option a -> () #
Hashable a => Hashable (Option a)
Instance details Defined in Data.Hashable.Class Methods hashWithSalt :: Int -> Option a -> Int # hash :: Option a -> Int #
Generic1 Option
Instance details Defined in Data.Semigroup Associated Types type Rep1 Option :: k -> Type # Methods from1 :: Option a -> Rep1 Option a # to1 :: Rep1 Option a -> Option a #
type Rep (Option a)	Since: base-4.9.0.0
Instance details Defined in Data.Semigroup type Rep (Option a) = D1 (MetaData "Option" "Data.Semigroup" "base" True) (C1 (MetaCons "Option" PrefixI True) (S1 (MetaSel (Just "getOption") NoSourceUnpackedness NoSourceStrictness DecidedLazy) (Rec0 (Maybe a))))
type Rep1 Option	Since: base-4.9.0.0
Instance details Defined in Data.Semigroup type Rep1 Option = D1 (MetaData "Option" "Data.Semigroup" "base" True) (C1 (MetaCons "Option" PrefixI True) (S1 (MetaSel (Just "getOption") NoSourceUnpackedness NoSourceStrictness DecidedLazy) (Rec1 Maybe)))

sortWith :: Ord b => (a -> b) -> [a] -> [a] #

The sortWith function sorts a list of elements using the user supplied function to project something out of each element

class Bifunctor (p :: Type -> Type -> Type) where #

A bifunctor is a type constructor that takes two type arguments and is a functor in both arguments. That is, unlike with Functor, a type constructor such as Either does not need to be partially applied for a Bifunctor instance, and the methods in this class permit mapping functions over the Left value or the Right value, or both at the same time.

Formally, the class Bifunctor represents a bifunctor from Hask -> Hask.

Intuitively it is a bifunctor where both the first and second arguments are covariant.

You can define a Bifunctor by either defining bimap or by defining both first and second.

If you supply bimap, you should ensure that:

bimap id id ≡ id

If you supply first and second, ensure:

first id ≡ id
second id ≡ id

If you supply both, you should also ensure:

bimap f g ≡ first f . second g

These ensure by parametricity:

bimap  (f . g) (h . i) ≡ bimap f h . bimap g i
first  (f . g) ≡ first  f . first  g
second (f . g) ≡ second f . second g

Since: base-4.8.0.0

Minimal complete definition

bimap | first, second

Methods

bimap :: (a -> b) -> (c -> d) -> p a c -> p b d #

Map over both arguments at the same time.

bimap f g ≡ first f . second g

Examples

Expand

>>> bimap toUpper (+1) ('j', 3)
('J',4)

>>> bimap toUpper (+1) (Left 'j')
Left 'J'

>>> bimap toUpper (+1) (Right 3)
Right 4

first :: (a -> b) -> p a c -> p b c #

Map covariantly over the first argument.

first f ≡ bimap f id

Examples

Expand

>>> first toUpper ('j', 3)
('J',3)

>>> first toUpper (Left 'j')
Left 'J'

second :: (b -> c) -> p a b -> p a c #

Map covariantly over the second argument.

second ≡ bimap id

Examples

Expand

>>> second (+1) ('j', 3)
('j',4)

>>> second (+1) (Right 3)
Right 4

Instances

Bifunctor Either	Since: base-4.8.0.0
Instance details Defined in Data.Bifunctor Methods bimap :: (a -> b) -> (c -> d) -> Either a c -> Either b d # first :: (a -> b) -> Either a c -> Either b c # second :: (b -> c) -> Either a b -> Either a c #
Bifunctor (,)	Since: base-4.8.0.0
Instance details Defined in Data.Bifunctor Methods bimap :: (a -> b) -> (c -> d) -> (a, c) -> (b, d) # first :: (a -> b) -> (a, c) -> (b, c) # second :: (b -> c) -> (a, b) -> (a, c) #
Bifunctor Arg	Since: base-4.9.0.0
Instance details Defined in Data.Semigroup Methods bimap :: (a -> b) -> (c -> d) -> Arg a c -> Arg b d # first :: (a -> b) -> Arg a c -> Arg b c # second :: (b -> c) -> Arg a b -> Arg a c #
Bifunctor ((,,) x1)	Since: base-4.8.0.0
Instance details Defined in Data.Bifunctor Methods bimap :: (a -> b) -> (c -> d) -> (x1, a, c) -> (x1, b, d) # first :: (a -> b) -> (x1, a, c) -> (x1, b, c) # second :: (b -> c) -> (x1, a, b) -> (x1, a, c) #
Bifunctor (Const :: Type -> Type -> Type)	Since: base-4.8.0.0
Instance details Defined in Data.Bifunctor Methods bimap :: (a -> b) -> (c -> d) -> Const a c -> Const b d # first :: (a -> b) -> Const a c -> Const b c # second :: (b -> c) -> Const a b -> Const a c #
Bifunctor (K1 i :: Type -> Type -> Type)	Since: base-4.9.0.0
Instance details Defined in Data.Bifunctor Methods bimap :: (a -> b) -> (c -> d) -> K1 i a c -> K1 i b d # first :: (a -> b) -> K1 i a c -> K1 i b c # second :: (b -> c) -> K1 i a b -> K1 i a c #
Bifunctor ((,,,) x1 x2)	Since: base-4.8.0.0
Instance details Defined in Data.Bifunctor Methods bimap :: (a -> b) -> (c -> d) -> (x1, x2, a, c) -> (x1, x2, b, d) # first :: (a -> b) -> (x1, x2, a, c) -> (x1, x2, b, c) # second :: (b -> c) -> (x1, x2, a, b) -> (x1, x2, a, c) #
Bifunctor ((,,,,) x1 x2 x3)	Since: base-4.8.0.0
Instance details Defined in Data.Bifunctor Methods bimap :: (a -> b) -> (c -> d) -> (x1, x2, x3, a, c) -> (x1, x2, x3, b, d) # first :: (a -> b) -> (x1, x2, x3, a, c) -> (x1, x2, x3, b, c) # second :: (b -> c) -> (x1, x2, x3, a, b) -> (x1, x2, x3, a, c) #
Bifunctor ((,,,,,) x1 x2 x3 x4)	Since: base-4.8.0.0
Instance details Defined in Data.Bifunctor Methods bimap :: (a -> b) -> (c -> d) -> (x1, x2, x3, x4, a, c) -> (x1, x2, x3, x4, b, d) # first :: (a -> b) -> (x1, x2, x3, x4, a, c) -> (x1, x2, x3, x4, b, c) # second :: (b -> c) -> (x1, x2, x3, x4, a, b) -> (x1, x2, x3, x4, a, c) #
Bifunctor ((,,,,,,) x1 x2 x3 x4 x5)	Since: base-4.8.0.0
Instance details Defined in Data.Bifunctor Methods bimap :: (a -> b) -> (c -> d) -> (x1, x2, x3, x4, x5, a, c) -> (x1, x2, x3, x4, x5, b, d) # first :: (a -> b) -> (x1, x2, x3, x4, x5, a, c) -> (x1, x2, x3, x4, x5, b, c) # second :: (b -> c) -> (x1, x2, x3, x4, x5, a, b) -> (x1, x2, x3, x4, x5, a, c) #

init :: NonEmpty a -> [a] #

Extract everything except the last element of the stream.

last :: NonEmpty a -> a #

Extract the last element of the stream.

tail :: NonEmpty a -> [a] #

Extract the possibly-empty tail of the stream.

head :: NonEmpty a -> a #

Extract the first element of the stream.

nonEmpty :: [a] -> Maybe (NonEmpty a) #

nonEmpty efficiently turns a normal list into a NonEmpty stream, producing Nothing if the input is empty.

showStackTrace :: IO (Maybe String) #

Get a string representation of the current execution stack state.

getStackTrace :: IO (Maybe [Location]) #

Get a trace of the current execution stack state.

Returns Nothing if stack trace support isn't available on host machine.

class Monad m => MonadIO (m :: Type -> Type) where #

Monads in which IO computations may be embedded. Any monad built by applying a sequence of monad transformers to the IO monad will be an instance of this class.

Instances should satisfy the following laws, which state that liftIO is a transformer of monads:

```
liftIO . return = return
```

liftIO (m >>= f) = liftIO m >>= (liftIO . f)

Methods

liftIO :: IO a -> m a #

Lift a computation from the IO monad.

Instances

MonadIO IO	Since: base-4.9.0.0
Instance details Defined in Control.Monad.IO.Class Methods liftIO :: IO a -> IO a #
MonadIO m => MonadIO (MaybeT m)
Instance details Defined in Control.Monad.Trans.Maybe Methods liftIO :: IO a -> MaybeT m a #
MonadIO m => MonadIO (ExceptT e m)
Instance details Defined in Control.Monad.Trans.Except Methods liftIO :: IO a -> ExceptT e m a #
MonadIO m => MonadIO (IdentityT m)
Instance details Defined in Control.Monad.Trans.Identity Methods liftIO :: IO a -> IdentityT m a #
(Error e, MonadIO m) => MonadIO (ErrorT e m)
Instance details Defined in Control.Monad.Trans.Error Methods liftIO :: IO a -> ErrorT e m a #
MonadIO m => MonadIO (StateT s m)
Instance details Defined in Control.Monad.Trans.State.Strict Methods liftIO :: IO a -> StateT s m a #
MonadIO m => MonadIO (ReaderT r m)
Instance details Defined in Control.Monad.Trans.Reader Methods liftIO :: IO a -> ReaderT r m a #

mfilter :: MonadPlus m => (a -> Bool) -> m a -> m a #

Direct MonadPlus equivalent of filter.

Examples

Expand

The filter function is just mfilter specialized to the list monad:

filter = ( mfilter :: (a -> Bool) -> [a] -> [a] )

An example using mfilter with the Maybe monad:

>>> mfilter odd (Just 1)
Just 1
>>> mfilter odd (Just 2)
Nothing

(<$!>) :: Monad m => (a -> b) -> m a -> m b infixl 4 #

Strict version of <$>.

Since: base-4.8.0.0

unless :: Applicative f => Bool -> f () -> f () #

The reverse of when.

replicateM_ :: Applicative m => Int -> m a -> m () #

Like replicateM, but discards the result.

replicateM :: Applicative m => Int -> m a -> m [a] #

replicateM n act performs the action n times, gathering the results.

foldM_ :: (Foldable t, Monad m) => (b -> a -> m b) -> b -> t a -> m () #

Like foldM, but discards the result.

foldM :: (Foldable t, Monad m) => (b -> a -> m b) -> b -> t a -> m b #

The foldM function is analogous to foldl, except that its result is encapsulated in a monad. Note that foldM works from left-to-right over the list arguments. This could be an issue where (>>) and the `folded function' are not commutative.

foldM f a1 [x1, x2, ..., xm]

==

do
  a2 <- f a1 x1
  a3 <- f a2 x2
  ...
  f am xm

If right-to-left evaluation is required, the input list should be reversed.

Note: foldM is the same as foldlM

zipWithM_ :: Applicative m => (a -> b -> m c) -> [a] -> [b] -> m () #

zipWithM_ is the extension of zipWithM which ignores the final result.

zipWithM :: Applicative m => (a -> b -> m c) -> [a] -> [b] -> m [c] #

The zipWithM function generalizes zipWith to arbitrary applicative functors.

mapAndUnzipM :: Applicative m => (a -> m (b, c)) -> [a] -> m ([b], [c]) #

The mapAndUnzipM function maps its first argument over a list, returning the result as a pair of lists. This function is mainly used with complicated data structures or a state-transforming monad.

forever :: Applicative f => f a -> f b #

Repeat an action indefinitely.

Examples

Expand

A common use of forever is to process input from network sockets, Handles, and channels (e.g. MVar and Chan).

For example, here is how we might implement an echo server, using forever both to listen for client connections on a network socket and to echo client input on client connection handles:

echoServer :: Socket -> IO ()
echoServer socket = forever $ do
  client <- accept socket
  forkFinally (echo client) (\_ -> hClose client)
  where
    echo :: Handle -> IO ()
    echo client = forever $
      hGetLine client >>= hPutStrLn client

(<=<) :: Monad m => (b -> m c) -> (a -> m b) -> a -> m c infixr 1 #

Right-to-left composition of Kleisli arrows. (>=>), with the arguments flipped.

Note how this operator resembles function composition (.):

(.)   ::            (b ->   c) -> (a ->   b) -> a ->   c
(<=<) :: Monad m => (b -> m c) -> (a -> m b) -> a -> m c

(>=>) :: Monad m => (a -> m b) -> (b -> m c) -> a -> m c infixr 1 #

Left-to-right composition of Kleisli arrows.

filterM :: Applicative m => (a -> m Bool) -> [a] -> m [a] #

This generalizes the list-based filter function.

foldMapDefault :: (Traversable t, Monoid m) => (a -> m) -> t a -> m #

This function may be used as a value for foldMap in a Foldable instance.

foldMapDefault f ≡ getConst . traverse (Const . f)

fmapDefault :: Traversable t => (a -> b) -> t a -> t b #

This function may be used as a value for fmap in a Functor instance, provided that traverse is defined. (Using fmapDefault with a Traversable instance defined only by sequenceA will result in infinite recursion.)

fmapDefault f ≡ runIdentity . traverse (Identity . f)

mapAccumR :: Traversable t => (a -> b -> (a, c)) -> a -> t b -> (a, t c) #

The mapAccumR function behaves like a combination of fmap and foldr; it applies a function to each element of a structure, passing an accumulating parameter from right to left, and returning a final value of this accumulator together with the new structure.

mapAccumL :: Traversable t => (a -> b -> (a, c)) -> a -> t b -> (a, t c) #

The mapAccumL function behaves like a combination of fmap and foldl; it applies a function to each element of a structure, passing an accumulating parameter from left to right, and returning a final value of this accumulator together with the new structure.

forM :: (Traversable t, Monad m) => t a -> (a -> m b) -> m (t b) #

forM is mapM with its arguments flipped. For a version that ignores the results see forM_.

optional :: Alternative f => f a -> f (Maybe a) #

One or none.

newtype ZipList a #

Lists, but with an Applicative functor based on zipping.

Constructors

ZipList
Fields getZipList :: [a]

Instances

Functor ZipList	Since: base-2.1
Instance details Defined in Control.Applicative Methods fmap :: (a -> b) -> ZipList a -> ZipList b # (<$) :: a -> ZipList b -> ZipList a #
Applicative ZipList	f '<$>' 'ZipList' xs1 '<>' ... '<>' 'ZipList' xsN = 'ZipList' (zipWithN f xs1 ... xsN) where `zipWithN` refers to the `zipWith` function of the appropriate arity (`zipWith`, `zipWith3`, `zipWith4`, ...). For example: (\a b c -> stimes c [a, b]) <$> ZipList "abcd" <> ZipList "567" <> ZipList [1..] = ZipList (zipWith3 (\a b c -> stimes c [a, b]) "abcd" "567" [1..]) = ZipList {getZipList = ["a5","b6b6","c7c7c7"]} Since: base-2.1
Instance details Defined in Control.Applicative Methods pure :: a -> ZipList a # (<>) :: ZipList (a -> b) -> ZipList a -> ZipList b # liftA2 :: (a -> b -> c) -> ZipList a -> ZipList b -> ZipList c # (>) :: ZipList a -> ZipList b -> ZipList b # (<*) :: ZipList a -> ZipList b -> ZipList a #
Foldable ZipList	Since: base-4.9.0.0
Instance details Defined in Control.Applicative Methods fold :: Monoid m => ZipList m -> m # foldMap :: Monoid m => (a -> m) -> ZipList a -> m # foldr :: (a -> b -> b) -> b -> ZipList a -> b # foldr' :: (a -> b -> b) -> b -> ZipList a -> b # foldl :: (b -> a -> b) -> b -> ZipList a -> b # foldl' :: (b -> a -> b) -> b -> ZipList a -> b # foldr1 :: (a -> a -> a) -> ZipList a -> a # foldl1 :: (a -> a -> a) -> ZipList a -> a # toList :: ZipList a -> [a] # null :: ZipList a -> Bool # length :: ZipList a -> Int # elem :: Eq a => a -> ZipList a -> Bool # maximum :: Ord a => ZipList a -> a # minimum :: Ord a => ZipList a -> a # sum :: Num a => ZipList a -> a # product :: Num a => ZipList a -> a #
Traversable ZipList	Since: base-4.9.0.0
Instance details Defined in Data.Traversable Methods traverse :: Applicative f => (a -> f b) -> ZipList a -> f (ZipList b) # sequenceA :: Applicative f => ZipList (f a) -> f (ZipList a) # mapM :: Monad m => (a -> m b) -> ZipList a -> m (ZipList b) # sequence :: Monad m => ZipList (m a) -> m (ZipList a) #
Alternative ZipList	Since: base-4.11.0.0
Instance details Defined in Control.Applicative Methods empty :: ZipList a # (<\|>) :: ZipList a -> ZipList a -> ZipList a # some :: ZipList a -> ZipList [a] # many :: ZipList a -> ZipList [a] #
NFData1 ZipList	Since: deepseq-1.4.3.0
Instance details Defined in Control.DeepSeq Methods liftRnf :: (a -> ()) -> ZipList a -> () #
Eq a => Eq (ZipList a)	Since: base-4.7.0.0
Instance details Defined in Control.Applicative Methods (==) :: ZipList a -> ZipList a -> Bool # (/=) :: ZipList a -> ZipList a -> Bool #
Ord a => Ord (ZipList a)	Since: base-4.7.0.0
Instance details Defined in Control.Applicative Methods compare :: ZipList a -> ZipList a -> Ordering # (<) :: ZipList a -> ZipList a -> Bool # (<=) :: ZipList a -> ZipList a -> Bool # (>) :: ZipList a -> ZipList a -> Bool # (>=) :: ZipList a -> ZipList a -> Bool # max :: ZipList a -> ZipList a -> ZipList a # min :: ZipList a -> ZipList a -> ZipList a #
Read a => Read (ZipList a)	Since: base-4.7.0.0
Instance details Defined in Control.Applicative Methods readsPrec :: Int -> ReadS (ZipList a) # readList :: ReadS [ZipList a] # readPrec :: ReadPrec (ZipList a) # readListPrec :: ReadPrec [ZipList a] #
Show a => Show (ZipList a)	Since: base-4.7.0.0
Instance details Defined in Control.Applicative Methods showsPrec :: Int -> ZipList a -> ShowS # show :: ZipList a -> String # showList :: [ZipList a] -> ShowS #
Generic (ZipList a)
Instance details Defined in Control.Applicative Associated Types type Rep (ZipList a) :: Type -> Type # Methods from :: ZipList a -> Rep (ZipList a) x # to :: Rep (ZipList a) x -> ZipList a #
NFData a => NFData (ZipList a)	Since: deepseq-1.4.0.0
Instance details Defined in Control.DeepSeq Methods rnf :: ZipList a -> () #
Container (ZipList a)
Instance details Defined in Universum.Container.Class Associated Types type Element (ZipList a) :: Type # Methods toList :: ZipList a -> [Element (ZipList a)] # null :: ZipList a -> Bool # foldr :: (Element (ZipList a) -> b -> b) -> b -> ZipList a -> b # foldl :: (b -> Element (ZipList a) -> b) -> b -> ZipList a -> b # foldl' :: (b -> Element (ZipList a) -> b) -> b -> ZipList a -> b # length :: ZipList a -> Int # elem :: Element (ZipList a) -> ZipList a -> Bool # maximum :: ZipList a -> Element (ZipList a) # minimum :: ZipList a -> Element (ZipList a) # foldMap :: Monoid m => (Element (ZipList a) -> m) -> ZipList a -> m # fold :: ZipList a -> Element (ZipList a) # foldr' :: (Element (ZipList a) -> b -> b) -> b -> ZipList a -> b # foldr1 :: (Element (ZipList a) -> Element (ZipList a) -> Element (ZipList a)) -> ZipList a -> Element (ZipList a) # foldl1 :: (Element (ZipList a) -> Element (ZipList a) -> Element (ZipList a)) -> ZipList a -> Element (ZipList a) # notElem :: Element (ZipList a) -> ZipList a -> Bool # all :: (Element (ZipList a) -> Bool) -> ZipList a -> Bool # any :: (Element (ZipList a) -> Bool) -> ZipList a -> Bool # and :: ZipList a -> Bool # or :: ZipList a -> Bool # find :: (Element (ZipList a) -> Bool) -> ZipList a -> Maybe (Element (ZipList a)) # safeHead :: ZipList a -> Maybe (Element (ZipList a)) #
Generic1 ZipList
Instance details Defined in Control.Applicative Associated Types type Rep1 ZipList :: k -> Type # Methods from1 :: ZipList a -> Rep1 ZipList a # to1 :: Rep1 ZipList a -> ZipList a #
type Rep (ZipList a)	Since: base-4.7.0.0
Instance details Defined in Control.Applicative type Rep (ZipList a) = D1 (MetaData "ZipList" "Control.Applicative" "base" True) (C1 (MetaCons "ZipList" PrefixI True) (S1 (MetaSel (Just "getZipList") NoSourceUnpackedness NoSourceStrictness DecidedLazy) (Rec0 [a])))
type Element (ZipList a)
Instance details Defined in Universum.Container.Class type Element (ZipList a) = ElementDefault (ZipList a)
type Rep1 ZipList	Since: base-4.7.0.0
Instance details Defined in Control.Applicative type Rep1 ZipList = D1 (MetaData "ZipList" "Control.Applicative" "base" True) (C1 (MetaCons "ZipList" PrefixI True) (S1 (MetaSel (Just "getZipList") NoSourceUnpackedness NoSourceStrictness DecidedLazy) (Rec1 [])))

(&&&) :: Arrow a => a b c -> a b c' -> a b (c, c') infixr 3 #

Fanout: send the input to both argument arrows and combine their output.

The default definition may be overridden with a more efficient version if desired.

newtype Identity a #

Identity functor and monad. (a non-strict monad)

Since: base-4.8.0.0

Constructors

Identity
Fields runIdentity :: a

Instances

Monad Identity	Since: base-4.8.0.0
Instance details Defined in Data.Functor.Identity Methods (>>=) :: Identity a -> (a -> Identity b) -> Identity b # (>>) :: Identity a -> Identity b -> Identity b # return :: a -> Identity a # fail :: String -> Identity a #
Functor Identity	Since: base-4.8.0.0
Instance details Defined in Data.Functor.Identity Methods fmap :: (a -> b) -> Identity a -> Identity b # (<$) :: a -> Identity b -> Identity a #
MonadFix Identity	Since: base-4.8.0.0
Instance details Defined in Data.Functor.Identity Methods mfix :: (a -> Identity a) -> Identity a #
Applicative Identity	Since: base-4.8.0.0
Instance details Defined in Data.Functor.Identity Methods pure :: a -> Identity a # (<>) :: Identity (a -> b) -> Identity a -> Identity b # liftA2 :: (a -> b -> c) -> Identity a -> Identity b -> Identity c # (>) :: Identity a -> Identity b -> Identity b # (<*) :: Identity a -> Identity b -> Identity a #
Foldable Identity	Since: base-4.8.0.0
Instance details Defined in Data.Functor.Identity Methods fold :: Monoid m => Identity m -> m # foldMap :: Monoid m => (a -> m) -> Identity a -> m # foldr :: (a -> b -> b) -> b -> Identity a -> b # foldr' :: (a -> b -> b) -> b -> Identity a -> b # foldl :: (b -> a -> b) -> b -> Identity a -> b # foldl' :: (b -> a -> b) -> b -> Identity a -> b # foldr1 :: (a -> a -> a) -> Identity a -> a # foldl1 :: (a -> a -> a) -> Identity a -> a # toList :: Identity a -> [a] # null :: Identity a -> Bool # length :: Identity a -> Int # elem :: Eq a => a -> Identity a -> Bool # maximum :: Ord a => Identity a -> a # minimum :: Ord a => Identity a -> a # sum :: Num a => Identity a -> a # product :: Num a => Identity a -> a #
Traversable Identity	Since: base-4.9.0.0
Instance details Defined in Data.Traversable Methods traverse :: Applicative f => (a -> f b) -> Identity a -> f (Identity b) # sequenceA :: Applicative f => Identity (f a) -> f (Identity a) # mapM :: Monad m => (a -> m b) -> Identity a -> m (Identity b) # sequence :: Monad m => Identity (m a) -> m (Identity a) #
NFData1 Identity	Since: deepseq-1.4.3.0
Instance details Defined in Control.DeepSeq Methods liftRnf :: (a -> ()) -> Identity a -> () #
Hashable1 Identity
Instance details Defined in Data.Hashable.Class Methods liftHashWithSalt :: (Int -> a -> Int) -> Int -> Identity a -> Int #
Bounded a => Bounded (Identity a)	Since: base-4.9.0.0
Instance details Defined in Data.Functor.Identity Methods minBound :: Identity a # maxBound :: Identity a #
Enum a => Enum (Identity a)	Since: base-4.9.0.0
Instance details Defined in Data.Functor.Identity Methods succ :: Identity a -> Identity a # pred :: Identity a -> Identity a # toEnum :: Int -> Identity a # fromEnum :: Identity a -> Int # enumFrom :: Identity a -> [Identity a] # enumFromThen :: Identity a -> Identity a -> [Identity a] # enumFromTo :: Identity a -> Identity a -> [Identity a] # enumFromThenTo :: Identity a -> Identity a -> Identity a -> [Identity a] #
Eq a => Eq (Identity a)	Since: base-4.8.0.0
Instance details Defined in Data.Functor.Identity Methods (==) :: Identity a -> Identity a -> Bool # (/=) :: Identity a -> Identity a -> Bool #
Floating a => Floating (Identity a)	Since: base-4.9.0.0
Instance details Defined in Data.Functor.Identity Methods pi :: Identity a # exp :: Identity a -> Identity a # log :: Identity a -> Identity a # sqrt :: Identity a -> Identity a # (**) :: Identity a -> Identity a -> Identity a # logBase :: Identity a -> Identity a -> Identity a # sin :: Identity a -> Identity a # cos :: Identity a -> Identity a # tan :: Identity a -> Identity a # asin :: Identity a -> Identity a # acos :: Identity a -> Identity a # atan :: Identity a -> Identity a # sinh :: Identity a -> Identity a # cosh :: Identity a -> Identity a # tanh :: Identity a -> Identity a # asinh :: Identity a -> Identity a # acosh :: Identity a -> Identity a # atanh :: Identity a -> Identity a # log1p :: Identity a -> Identity a # expm1 :: Identity a -> Identity a # log1pexp :: Identity a -> Identity a # log1mexp :: Identity a -> Identity a #
Fractional a => Fractional (Identity a)	Since: base-4.9.0.0
Instance details Defined in Data.Functor.Identity Methods (/) :: Identity a -> Identity a -> Identity a # recip :: Identity a -> Identity a # fromRational :: Rational -> Identity a #
Integral a => Integral (Identity a)	Since: base-4.9.0.0
Instance details Defined in Data.Functor.Identity Methods quot :: Identity a -> Identity a -> Identity a # rem :: Identity a -> Identity a -> Identity a # div :: Identity a -> Identity a -> Identity a # mod :: Identity a -> Identity a -> Identity a # quotRem :: Identity a -> Identity a -> (Identity a, Identity a) # divMod :: Identity a -> Identity a -> (Identity a, Identity a) # toInteger :: Identity a -> Integer #
Num a => Num (Identity a)	Since: base-4.9.0.0
Instance details Defined in Data.Functor.Identity Methods (+) :: Identity a -> Identity a -> Identity a # (-) :: Identity a -> Identity a -> Identity a # (*) :: Identity a -> Identity a -> Identity a # negate :: Identity a -> Identity a # abs :: Identity a -> Identity a # signum :: Identity a -> Identity a # fromInteger :: Integer -> Identity a #
Ord a => Ord (Identity a)	Since: base-4.8.0.0
Instance details Defined in Data.Functor.Identity Methods compare :: Identity a -> Identity a -> Ordering # (<) :: Identity a -> Identity a -> Bool # (<=) :: Identity a -> Identity a -> Bool # (>) :: Identity a -> Identity a -> Bool # (>=) :: Identity a -> Identity a -> Bool # max :: Identity a -> Identity a -> Identity a # min :: Identity a -> Identity a -> Identity a #
Read a => Read (Identity a)	This instance would be equivalent to the derived instances of the `Identity` newtype if the `runIdentity` field were removed Since: base-4.8.0.0
Instance details Defined in Data.Functor.Identity Methods readsPrec :: Int -> ReadS (Identity a) # readList :: ReadS [Identity a] # readPrec :: ReadPrec (Identity a) # readListPrec :: ReadPrec [Identity a] #
Real a => Real (Identity a)	Since: base-4.9.0.0
Instance details Defined in Data.Functor.Identity Methods toRational :: Identity a -> Rational #
RealFloat a => RealFloat (Identity a)	Since: base-4.9.0.0
Instance details Defined in Data.Functor.Identity Methods floatRadix :: Identity a -> Integer # floatDigits :: Identity a -> Int # floatRange :: Identity a -> (Int, Int) # decodeFloat :: Identity a -> (Integer, Int) # encodeFloat :: Integer -> Int -> Identity a # exponent :: Identity a -> Int # significand :: Identity a -> Identity a # scaleFloat :: Int -> Identity a -> Identity a # isNaN :: Identity a -> Bool # isInfinite :: Identity a -> Bool # isDenormalized :: Identity a -> Bool # isNegativeZero :: Identity a -> Bool # isIEEE :: Identity a -> Bool # atan2 :: Identity a -> Identity a -> Identity a #
RealFrac a => RealFrac (Identity a)	Since: base-4.9.0.0
Instance details Defined in Data.Functor.Identity Methods properFraction :: Integral b => Identity a -> (b, Identity a) # truncate :: Integral b => Identity a -> b # round :: Integral b => Identity a -> b # ceiling :: Integral b => Identity a -> b # floor :: Integral b => Identity a -> b #
Show a => Show (Identity a)	This instance would be equivalent to the derived instances of the `Identity` newtype if the `runIdentity` field were removed Since: base-4.8.0.0
Instance details Defined in Data.Functor.Identity Methods showsPrec :: Int -> Identity a -> ShowS # show :: Identity a -> String # showList :: [Identity a] -> ShowS #
Ix a => Ix (Identity a)	Since: base-4.9.0.0
Instance details Defined in Data.Functor.Identity Methods range :: (Identity a, Identity a) -> [Identity a] # index :: (Identity a, Identity a) -> Identity a -> Int # unsafeIndex :: (Identity a, Identity a) -> Identity a -> Int inRange :: (Identity a, Identity a) -> Identity a -> Bool # rangeSize :: (Identity a, Identity a) -> Int # unsafeRangeSize :: (Identity a, Identity a) -> Int
IsString a => IsString (Identity a)	Since: base-4.9.0.0
Instance details Defined in Data.String Methods fromString :: String -> Identity a #
Generic (Identity a)
Instance details Defined in Data.Functor.Identity Associated Types type Rep (Identity a) :: Type -> Type # Methods from :: Identity a -> Rep (Identity a) x # to :: Rep (Identity a) x -> Identity a #
Semigroup a => Semigroup (Identity a)	Since: base-4.9.0.0
Instance details Defined in Data.Functor.Identity Methods (<>) :: Identity a -> Identity a -> Identity a # sconcat :: NonEmpty (Identity a) -> Identity a # stimes :: Integral b => b -> Identity a -> Identity a #
Monoid a => Monoid (Identity a)	Since: base-4.9.0.0
Instance details Defined in Data.Functor.Identity Methods mempty :: Identity a # mappend :: Identity a -> Identity a -> Identity a # mconcat :: [Identity a] -> Identity a #
Storable a => Storable (Identity a)	Since: base-4.9.0.0
Instance details Defined in Data.Functor.Identity Methods sizeOf :: Identity a -> Int # alignment :: Identity a -> Int # peekElemOff :: Ptr (Identity a) -> Int -> IO (Identity a) # pokeElemOff :: Ptr (Identity a) -> Int -> Identity a -> IO () # peekByteOff :: Ptr b -> Int -> IO (Identity a) # pokeByteOff :: Ptr b -> Int -> Identity a -> IO () # peek :: Ptr (Identity a) -> IO (Identity a) # poke :: Ptr (Identity a) -> Identity a -> IO () #
Bits a => Bits (Identity a)	Since: base-4.9.0.0
Instance details Defined in Data.Functor.Identity Methods (.&.) :: Identity a -> Identity a -> Identity a # (.\|.) :: Identity a -> Identity a -> Identity a # xor :: Identity a -> Identity a -> Identity a # complement :: Identity a -> Identity a # shift :: Identity a -> Int -> Identity a # rotate :: Identity a -> Int -> Identity a # zeroBits :: Identity a # bit :: Int -> Identity a # setBit :: Identity a -> Int -> Identity a # clearBit :: Identity a -> Int -> Identity a # complementBit :: Identity a -> Int -> Identity a # testBit :: Identity a -> Int -> Bool # bitSizeMaybe :: Identity a -> Maybe Int # bitSize :: Identity a -> Int # isSigned :: Identity a -> Bool # shiftL :: Identity a -> Int -> Identity a # unsafeShiftL :: Identity a -> Int -> Identity a # shiftR :: Identity a -> Int -> Identity a # unsafeShiftR :: Identity a -> Int -> Identity a # rotateL :: Identity a -> Int -> Identity a # rotateR :: Identity a -> Int -> Identity a # popCount :: Identity a -> Int #
FiniteBits a => FiniteBits (Identity a)	Since: base-4.9.0.0
Instance details Defined in Data.Functor.Identity Methods finiteBitSize :: Identity a -> Int # countLeadingZeros :: Identity a -> Int # countTrailingZeros :: Identity a -> Int #
NFData a => NFData (Identity a)	Since: deepseq-1.4.0.0
Instance details Defined in Control.DeepSeq Methods rnf :: Identity a -> () #
Hashable a => Hashable (Identity a)
Instance details Defined in Data.Hashable.Class Methods hashWithSalt :: Int -> Identity a -> Int # hash :: Identity a -> Int #
(TypeError (DisallowInstance "Identity") :: Constraint) => Container (Identity a)
Instance details Defined in Universum.Container.Class Associated Types type Element (Identity a) :: Type # Methods toList :: Identity a -> [Element (Identity a)] # null :: Identity a -> Bool # foldr :: (Element (Identity a) -> b -> b) -> b -> Identity a -> b # foldl :: (b -> Element (Identity a) -> b) -> b -> Identity a -> b # foldl' :: (b -> Element (Identity a) -> b) -> b -> Identity a -> b # length :: Identity a -> Int # elem :: Element (Identity a) -> Identity a -> Bool # maximum :: Identity a -> Element (Identity a) # minimum :: Identity a -> Element (Identity a) # foldMap :: Monoid m => (Element (Identity a) -> m) -> Identity a -> m # fold :: Identity a -> Element (Identity a) # foldr' :: (Element (Identity a) -> b -> b) -> b -> Identity a -> b # foldr1 :: (Element (Identity a) -> Element (Identity a) -> Element (Identity a)) -> Identity a -> Element (Identity a) # foldl1 :: (Element (Identity a) -> Element (Identity a) -> Element (Identity a)) -> Identity a -> Element (Identity a) # notElem :: Element (Identity a) -> Identity a -> Bool # all :: (Element (Identity a) -> Bool) -> Identity a -> Bool # any :: (Element (Identity a) -> Bool) -> Identity a -> Bool # and :: Identity a -> Bool # or :: Identity a -> Bool # find :: (Element (Identity a) -> Bool) -> Identity a -> Maybe (Element (Identity a)) # safeHead :: Identity a -> Maybe (Element (Identity a)) #
Generic1 Identity
Instance details Defined in Data.Functor.Identity Associated Types type Rep1 Identity :: k -> Type # Methods from1 :: Identity a -> Rep1 Identity a # to1 :: Rep1 Identity a -> Identity a #
type Rep (Identity a)	Since: base-4.8.0.0
Instance details Defined in Data.Functor.Identity type Rep (Identity a) = D1 (MetaData "Identity" "Data.Functor.Identity" "base" True) (C1 (MetaCons "Identity" PrefixI True) (S1 (MetaSel (Just "runIdentity") NoSourceUnpackedness NoSourceStrictness DecidedLazy) (Rec0 a)))
type Element (Identity a)
Instance details Defined in Universum.Container.Class type Element (Identity a) = ElementDefault (Identity a)
type Rep1 Identity	Since: base-4.8.0.0
Instance details Defined in Data.Functor.Identity type Rep1 Identity = D1 (MetaData "Identity" "Data.Functor.Identity" "base" True) (C1 (MetaCons "Identity" PrefixI True) (S1 (MetaSel (Just "runIdentity") NoSourceUnpackedness NoSourceStrictness DecidedLazy) Par1))

stderr :: Handle #

A handle managing output to the Haskell program's standard error channel.

stdin :: Handle #

A handle managing input from the Haskell program's standard input channel.

withFrozenCallStack :: HasCallStack => (HasCallStack -> a) -> a #

Perform some computation without adding new entries to the CallStack.

Since: base-4.9.0.0

callStack :: HasCallStack -> CallStack #

Return the current CallStack.

Does *not* include the call-site of callStack.

Since: base-4.9.0.0

writeTVar :: TVar a -> a -> STM () #

Write the supplied value into a TVar.

readTVar :: TVar a -> STM a #

Return the current value stored in a TVar.

newTVar :: a -> STM (TVar a) #

Create a new TVar holding a value supplied

data STM a #

A monad supporting atomic memory transactions.

Instances

Monad STM	Since: base-4.3.0.0
Instance details Defined in GHC.Conc.Sync Methods (>>=) :: STM a -> (a -> STM b) -> STM b # (>>) :: STM a -> STM b -> STM b # return :: a -> STM a # fail :: String -> STM a #
Functor STM	Since: base-4.3.0.0
Instance details Defined in GHC.Conc.Sync Methods fmap :: (a -> b) -> STM a -> STM b # (<$) :: a -> STM b -> STM a #
Applicative STM	Since: base-4.8.0.0
Instance details Defined in GHC.Conc.Sync Methods pure :: a -> STM a # (<>) :: STM (a -> b) -> STM a -> STM b # liftA2 :: (a -> b -> c) -> STM a -> STM b -> STM c # (>) :: STM a -> STM b -> STM b # (<*) :: STM a -> STM b -> STM a #
Alternative STM	Since: base-4.8.0.0
Instance details Defined in GHC.Conc.Sync Methods empty :: STM a # (<\|>) :: STM a -> STM a -> STM a # some :: STM a -> STM [a] # many :: STM a -> STM [a] #
MonadPlus STM	Since: base-4.3.0.0
Instance details Defined in GHC.Conc.Sync Methods mzero :: STM a # mplus :: STM a -> STM a -> STM a #
MonadThrow STM
Instance details Defined in Control.Monad.Catch Methods throwM :: Exception e => e -> STM a #
MonadCatch STM
Instance details Defined in Control.Monad.Catch Methods catch :: Exception e => STM a -> (e -> STM a) -> STM a #

data TVar a #

Shared memory locations that support atomic memory transactions.

Instances

Eq (TVar a)	Since: base-4.8.0.0
Instance details Defined in GHC.Conc.Sync Methods (==) :: TVar a -> TVar a -> Bool # (/=) :: TVar a -> TVar a -> Bool #

stdout :: Handle #

A handle managing output to the Haskell program's standard output channel.

data IORef a #

A mutable variable in the IO monad

Instances

NFData1 IORef	Since: deepseq-1.4.3.0
Instance details Defined in Control.DeepSeq Methods liftRnf :: (a -> ()) -> IORef a -> () #
Eq (IORef a)	^ Pointer equality. Since: base-4.1.0.0
Instance details Defined in GHC.IORef Methods (==) :: IORef a -> IORef a -> Bool # (/=) :: IORef a -> IORef a -> Bool #
NFData (IORef a)	NOTE: Only strict in the reference and not the referenced value. Since: deepseq-1.4.2.0
Instance details Defined in Control.DeepSeq Methods rnf :: IORef a -> () #

type FilePath = String #

File and directory names are values of type String, whose precise meaning is operating system dependent. Files can be opened, yielding a handle which can then be used to operate on the contents of that file.

prettyCallStack :: CallStack -> String #

Pretty print a CallStack.

Since: base-4.9.0.0

prettySrcLoc :: SrcLoc -> String #

Pretty print a SrcLoc.

Since: base-4.9.0.0

class (Typeable e, Show e) => Exception e where #

Any type that you wish to throw or catch as an exception must be an instance of the Exception class. The simplest case is a new exception type directly below the root:

data MyException = ThisException | ThatException
    deriving Show

instance Exception MyException

The default method definitions in the Exception class do what we need in this case. You can now throw and catch ThisException and ThatException as exceptions:

*Main> throw ThisException `catch` \e -> putStrLn ("Caught " ++ show (e :: MyException))
Caught ThisException

In more complicated examples, you may wish to define a whole hierarchy of exceptions:

---------------------------------------------------------------------
-- Make the root exception type for all the exceptions in a compiler

data SomeCompilerException = forall e . Exception e => SomeCompilerException e

instance Show SomeCompilerException where
    show (SomeCompilerException e) = show e

instance Exception SomeCompilerException

compilerExceptionToException :: Exception e => e -> SomeException
compilerExceptionToException = toException . SomeCompilerException

compilerExceptionFromException :: Exception e => SomeException -> Maybe e
compilerExceptionFromException x = do
    SomeCompilerException a <- fromException x
    cast a

---------------------------------------------------------------------
-- Make a subhierarchy for exceptions in the frontend of the compiler

data SomeFrontendException = forall e . Exception e => SomeFrontendException e

instance Show SomeFrontendException where
    show (SomeFrontendException e) = show e

instance Exception SomeFrontendException where
    toException = compilerExceptionToException
    fromException = compilerExceptionFromException

frontendExceptionToException :: Exception e => e -> SomeException
frontendExceptionToException = toException . SomeFrontendException

frontendExceptionFromException :: Exception e => SomeException -> Maybe e
frontendExceptionFromException x = do
    SomeFrontendException a <- fromException x
    cast a

---------------------------------------------------------------------
-- Make an exception type for a particular frontend compiler exception

data MismatchedParentheses = MismatchedParentheses
    deriving Show

instance Exception MismatchedParentheses where
    toException   = frontendExceptionToException
    fromException = frontendExceptionFromException

We can now catch a MismatchedParentheses exception as MismatchedParentheses, SomeFrontendException or SomeCompilerException, but not other types, e.g. IOException:

*Main> throw MismatchedParentheses `catch` \e -> putStrLn ("Caught " ++ show (e :: MismatchedParentheses))
Caught MismatchedParentheses
*Main> throw MismatchedParentheses `catch` \e -> putStrLn ("Caught " ++ show (e :: SomeFrontendException))
Caught MismatchedParentheses
*Main> throw MismatchedParentheses `catch` \e -> putStrLn ("Caught " ++ show (e :: SomeCompilerException))
Caught MismatchedParentheses
*Main> throw MismatchedParentheses `catch` \e -> putStrLn ("Caught " ++ show (e :: IOException))
*** Exception: MismatchedParentheses

Minimal complete definition

Nothing

Methods

toException :: e -> SomeException #

fromException :: SomeException -> Maybe e #

displayException :: e -> String #

Render this exception value in a human-friendly manner.

Default implementation: show.

Since: base-4.8.0.0

Instances

Exception Void	Since: base-4.8.0.0
Instance details Defined in Data.Void Methods toException :: Void -> SomeException # fromException :: SomeException -> Maybe Void # displayException :: Void -> String #
Exception BlockedIndefinitelyOnMVar	Since: base-4.1.0.0
Instance details Defined in GHC.IO.Exception Methods toException :: BlockedIndefinitelyOnMVar -> SomeException # fromException :: SomeException -> Maybe BlockedIndefinitelyOnMVar # displayException :: BlockedIndefinitelyOnMVar -> String #
Exception BlockedIndefinitelyOnSTM	Since: base-4.1.0.0
Instance details Defined in GHC.IO.Exception Methods toException :: BlockedIndefinitelyOnSTM -> SomeException # fromException :: SomeException -> Maybe BlockedIndefinitelyOnSTM # displayException :: BlockedIndefinitelyOnSTM -> String #
Exception Deadlock	Since: base-4.1.0.0
Instance details Defined in GHC.IO.Exception Methods toException :: Deadlock -> SomeException # fromException :: SomeException -> Maybe Deadlock # displayException :: Deadlock -> String #
Exception AllocationLimitExceeded	Since: base-4.8.0.0
Instance details Defined in GHC.IO.Exception Methods toException :: AllocationLimitExceeded -> SomeException # fromException :: SomeException -> Maybe AllocationLimitExceeded # displayException :: AllocationLimitExceeded -> String #
Exception CompactionFailed	Since: base-4.10.0.0
Instance details Defined in GHC.IO.Exception Methods toException :: CompactionFailed -> SomeException # fromException :: SomeException -> Maybe CompactionFailed # displayException :: CompactionFailed -> String #
Exception AssertionFailed	Since: base-4.1.0.0
Instance details Defined in GHC.IO.Exception Methods toException :: AssertionFailed -> SomeException # fromException :: SomeException -> Maybe AssertionFailed # displayException :: AssertionFailed -> String #
Exception SomeAsyncException	Since: base-4.7.0.0
Instance details Defined in GHC.IO.Exception Methods toException :: SomeAsyncException -> SomeException # fromException :: SomeException -> Maybe SomeAsyncException # displayException :: SomeAsyncException -> String #
Exception AsyncException	Since: base-4.7.0.0
Instance details Defined in GHC.IO.Exception Methods toException :: AsyncException -> SomeException # fromException :: SomeException -> Maybe AsyncException # displayException :: AsyncException -> String #
Exception ArrayException	Since: base-4.1.0.0
Instance details Defined in GHC.IO.Exception Methods toException :: ArrayException -> SomeException # fromException :: SomeException -> Maybe ArrayException # displayException :: ArrayException -> String #
Exception FixIOException	Since: base-4.11.0.0
Instance details Defined in GHC.IO.Exception Methods toException :: FixIOException -> SomeException # fromException :: SomeException -> Maybe FixIOException # displayException :: FixIOException -> String #
Exception ExitCode	Since: base-4.1.0.0
Instance details Defined in GHC.IO.Exception Methods toException :: ExitCode -> SomeException # fromException :: SomeException -> Maybe ExitCode # displayException :: ExitCode -> String #
Exception IOException	Since: base-4.1.0.0
Instance details Defined in GHC.IO.Exception Methods toException :: IOException -> SomeException # fromException :: SomeException -> Maybe IOException # displayException :: IOException -> String #
Exception ErrorCall	Since: base-4.0.0.0
Instance details Defined in GHC.Exception Methods toException :: ErrorCall -> SomeException # fromException :: SomeException -> Maybe ErrorCall # displayException :: ErrorCall -> String #
Exception ArithException	Since: base-4.0.0.0
Instance details Defined in GHC.Exception.Type Methods toException :: ArithException -> SomeException # fromException :: SomeException -> Maybe ArithException # displayException :: ArithException -> String #
Exception SomeException	Since: base-3.0
Instance details Defined in GHC.Exception.Type Methods toException :: SomeException -> SomeException # fromException :: SomeException -> Maybe SomeException # displayException :: SomeException -> String #
Exception StringException
Instance details Defined in Control.Exception.Safe Methods toException :: StringException -> SomeException # fromException :: SomeException -> Maybe StringException # displayException :: StringException -> String #
Exception SyncExceptionWrapper
Instance details Defined in Control.Exception.Safe Methods toException :: SyncExceptionWrapper -> SomeException # fromException :: SomeException -> Maybe SyncExceptionWrapper # displayException :: SyncExceptionWrapper -> String #
Exception AsyncExceptionWrapper
Instance details Defined in Control.Exception.Safe Methods toException :: AsyncExceptionWrapper -> SomeException # fromException :: SomeException -> Maybe AsyncExceptionWrapper # displayException :: AsyncExceptionWrapper -> String #
Exception UnicodeException
Instance details Defined in Data.Text.Encoding.Error Methods toException :: UnicodeException -> SomeException # fromException :: SomeException -> Maybe UnicodeException # displayException :: UnicodeException -> String #
Exception Bug
Instance details Defined in Universum.Exception Methods toException :: Bug -> SomeException # fromException :: SomeException -> Maybe Bug # displayException :: Bug -> String #

newtype Const a (b :: k) :: forall k. Type -> k -> Type #

The Const functor.

Constructors

Const
Fields getConst :: a

Instances

Generic1 (Const a :: k -> Type)
Instance details Defined in Data.Functor.Const Associated Types type Rep1 (Const a) :: k -> Type # Methods from1 :: Const a a0 -> Rep1 (Const a) a0 # to1 :: Rep1 (Const a) a0 -> Const a a0 #
Bifunctor (Const :: Type -> Type -> Type)	Since: base-4.8.0.0
Instance details Defined in Data.Bifunctor Methods bimap :: (a -> b) -> (c -> d) -> Const a c -> Const b d # first :: (a -> b) -> Const a c -> Const b c # second :: (b -> c) -> Const a b -> Const a c #
NFData2 (Const :: Type -> Type -> Type)	Since: deepseq-1.4.3.0
Instance details Defined in Control.DeepSeq Methods liftRnf2 :: (a -> ()) -> (b -> ()) -> Const a b -> () #
Hashable2 (Const :: Type -> Type -> Type)
Instance details Defined in Data.Hashable.Class Methods liftHashWithSalt2 :: (Int -> a -> Int) -> (Int -> b -> Int) -> Int -> Const a b -> Int #
Functor (Const m :: Type -> Type)	Since: base-2.1
Instance details Defined in Data.Functor.Const Methods fmap :: (a -> b) -> Const m a -> Const m b # (<$) :: a -> Const m b -> Const m a #
Monoid m => Applicative (Const m :: Type -> Type)	Since: base-2.0.1
Instance details Defined in Data.Functor.Const Methods pure :: a -> Const m a # (<>) :: Const m (a -> b) -> Const m a -> Const m b # liftA2 :: (a -> b -> c) -> Const m a -> Const m b -> Const m c # (>) :: Const m a -> Const m b -> Const m b # (<*) :: Const m a -> Const m b -> Const m a #
Foldable (Const m :: Type -> Type)	Since: base-4.7.0.0
Instance details Defined in Data.Functor.Const Methods fold :: Monoid m0 => Const m m0 -> m0 # foldMap :: Monoid m0 => (a -> m0) -> Const m a -> m0 # foldr :: (a -> b -> b) -> b -> Const m a -> b # foldr' :: (a -> b -> b) -> b -> Const m a -> b # foldl :: (b -> a -> b) -> b -> Const m a -> b # foldl' :: (b -> a -> b) -> b -> Const m a -> b # foldr1 :: (a -> a -> a) -> Const m a -> a # foldl1 :: (a -> a -> a) -> Const m a -> a # toList :: Const m a -> [a] # null :: Const m a -> Bool # length :: Const m a -> Int # elem :: Eq a => a -> Const m a -> Bool # maximum :: Ord a => Const m a -> a # minimum :: Ord a => Const m a -> a # sum :: Num a => Const m a -> a # product :: Num a => Const m a -> a #
Traversable (Const m :: Type -> Type)	Since: base-4.7.0.0
Instance details Defined in Data.Traversable Methods traverse :: Applicative f => (a -> f b) -> Const m a -> f (Const m b) # sequenceA :: Applicative f => Const m (f a) -> f (Const m a) # mapM :: Monad m0 => (a -> m0 b) -> Const m a -> m0 (Const m b) # sequence :: Monad m0 => Const m (m0 a) -> m0 (Const m a) #
NFData a => NFData1 (Const a :: Type -> Type)	Since: deepseq-1.4.3.0
Instance details Defined in Control.DeepSeq Methods liftRnf :: (a0 -> ()) -> Const a a0 -> () #
Hashable a => Hashable1 (Const a :: Type -> Type)
Instance details Defined in Data.Hashable.Class Methods liftHashWithSalt :: (Int -> a0 -> Int) -> Int -> Const a a0 -> Int #
Bounded a => Bounded (Const a b)	Since: base-4.9.0.0
Instance details Defined in Data.Functor.Const Methods minBound :: Const a b # maxBound :: Const a b #
Enum a => Enum (Const a b)	Since: base-4.9.0.0
Instance details Defined in Data.Functor.Const Methods succ :: Const a b -> Const a b # pred :: Const a b -> Const a b # toEnum :: Int -> Const a b # fromEnum :: Const a b -> Int # enumFrom :: Const a b -> [Const a b] # enumFromThen :: Const a b -> Const a b -> [Const a b] # enumFromTo :: Const a b -> Const a b -> [Const a b] # enumFromThenTo :: Const a b -> Const a b -> Const a b -> [Const a b] #
Eq a => Eq (Const a b)	Since: base-4.9.0.0
Instance details Defined in Data.Functor.Const Methods (==) :: Const a b -> Const a b -> Bool # (/=) :: Const a b -> Const a b -> Bool #
Floating a => Floating (Const a b)	Since: base-4.9.0.0
Instance details Defined in Data.Functor.Const Methods pi :: Const a b # exp :: Const a b -> Const a b # log :: Const a b -> Const a b # sqrt :: Const a b -> Const a b # (**) :: Const a b -> Const a b -> Const a b # logBase :: Const a b -> Const a b -> Const a b # sin :: Const a b -> Const a b # cos :: Const a b -> Const a b # tan :: Const a b -> Const a b # asin :: Const a b -> Const a b # acos :: Const a b -> Const a b # atan :: Const a b -> Const a b # sinh :: Const a b -> Const a b # cosh :: Const a b -> Const a b # tanh :: Const a b -> Const a b # asinh :: Const a b -> Const a b # acosh :: Const a b -> Const a b # atanh :: Const a b -> Const a b # log1p :: Const a b -> Const a b # expm1 :: Const a b -> Const a b # log1pexp :: Const a b -> Const a b # log1mexp :: Const a b -> Const a b #
Fractional a => Fractional (Const a b)	Since: base-4.9.0.0
Instance details Defined in Data.Functor.Const Methods (/) :: Const a b -> Const a b -> Const a b # recip :: Const a b -> Const a b # fromRational :: Rational -> Const a b #
Integral a => Integral (Const a b)	Since: base-4.9.0.0
Instance details Defined in Data.Functor.Const Methods quot :: Const a b -> Const a b -> Const a b # rem :: Const a b -> Const a b -> Const a b # div :: Const a b -> Const a b -> Const a b # mod :: Const a b -> Const a b -> Const a b # quotRem :: Const a b -> Const a b -> (Const a b, Const a b) # divMod :: Const a b -> Const a b -> (Const a b, Const a b) # toInteger :: Const a b -> Integer #
Num a => Num (Const a b)	Since: base-4.9.0.0
Instance details Defined in Data.Functor.Const Methods (+) :: Const a b -> Const a b -> Const a b # (-) :: Const a b -> Const a b -> Const a b # (*) :: Const a b -> Const a b -> Const a b # negate :: Const a b -> Const a b # abs :: Const a b -> Const a b # signum :: Const a b -> Const a b # fromInteger :: Integer -> Const a b #
Ord a => Ord (Const a b)	Since: base-4.9.0.0
Instance details Defined in Data.Functor.Const Methods compare :: Const a b -> Const a b -> Ordering # (<) :: Const a b -> Const a b -> Bool # (<=) :: Const a b -> Const a b -> Bool # (>) :: Const a b -> Const a b -> Bool # (>=) :: Const a b -> Const a b -> Bool # max :: Const a b -> Const a b -> Const a b # min :: Const a b -> Const a b -> Const a b #
Read a => Read (Const a b)	This instance would be equivalent to the derived instances of the `Const` newtype if the `runConst` field were removed Since: base-4.8.0.0
Instance details Defined in Data.Functor.Const Methods readsPrec :: Int -> ReadS (Const a b) # readList :: ReadS [Const a b] # readPrec :: ReadPrec (Const a b) # readListPrec :: ReadPrec [Const a b] #
Real a => Real (Const a b)	Since: base-4.9.0.0
Instance details Defined in Data.Functor.Const Methods toRational :: Const a b -> Rational #
RealFloat a => RealFloat (Const a b)	Since: base-4.9.0.0
Instance details Defined in Data.Functor.Const Methods floatRadix :: Const a b -> Integer # floatDigits :: Const a b -> Int # floatRange :: Const a b -> (Int, Int) # decodeFloat :: Const a b -> (Integer, Int) # encodeFloat :: Integer -> Int -> Const a b # exponent :: Const a b -> Int # significand :: Const a b -> Const a b # scaleFloat :: Int -> Const a b -> Const a b # isNaN :: Const a b -> Bool # isInfinite :: Const a b -> Bool # isDenormalized :: Const a b -> Bool # isNegativeZero :: Const a b -> Bool # isIEEE :: Const a b -> Bool # atan2 :: Const a b -> Const a b -> Const a b #
RealFrac a => RealFrac (Const a b)	Since: base-4.9.0.0
Instance details Defined in Data.Functor.Const Methods properFraction :: Integral b0 => Const a b -> (b0, Const a b) # truncate :: Integral b0 => Const a b -> b0 # round :: Integral b0 => Const a b -> b0 # ceiling :: Integral b0 => Const a b -> b0 # floor :: Integral b0 => Const a b -> b0 #
Show a => Show (Const a b)	This instance would be equivalent to the derived instances of the `Const` newtype if the `runConst` field were removed Since: base-4.8.0.0
Instance details Defined in Data.Functor.Const Methods showsPrec :: Int -> Const a b -> ShowS # show :: Const a b -> String # showList :: [Const a b] -> ShowS #
Ix a => Ix (Const a b)	Since: base-4.9.0.0
Instance details Defined in Data.Functor.Const Methods range :: (Const a b, Const a b) -> [Const a b] # index :: (Const a b, Const a b) -> Const a b -> Int # unsafeIndex :: (Const a b, Const a b) -> Const a b -> Int inRange :: (Const a b, Const a b) -> Const a b -> Bool # rangeSize :: (Const a b, Const a b) -> Int # unsafeRangeSize :: (Const a b, Const a b) -> Int
IsString a => IsString (Const a b)	Since: base-4.9.0.0
Instance details Defined in Data.String Methods fromString :: String -> Const a b #
Generic (Const a b)
Instance details Defined in Data.Functor.Const Associated Types type Rep (Const a b) :: Type -> Type # Methods from :: Const a b -> Rep (Const a b) x # to :: Rep (Const a b) x -> Const a b #
Semigroup a => Semigroup (Const a b)	Since: base-4.9.0.0
Instance details Defined in Data.Functor.Const Methods (<>) :: Const a b -> Const a b -> Const a b # sconcat :: NonEmpty (Const a b) -> Const a b # stimes :: Integral b0 => b0 -> Const a b -> Const a b #
Monoid a => Monoid (Const a b)	Since: base-4.9.0.0
Instance details Defined in Data.Functor.Const Methods mempty :: Const a b # mappend :: Const a b -> Const a b -> Const a b # mconcat :: [Const a b] -> Const a b #
Storable a => Storable (Const a b)	Since: base-4.9.0.0
Instance details Defined in Data.Functor.Const Methods sizeOf :: Const a b -> Int # alignment :: Const a b -> Int # peekElemOff :: Ptr (Const a b) -> Int -> IO (Const a b) # pokeElemOff :: Ptr (Const a b) -> Int -> Const a b -> IO () # peekByteOff :: Ptr b0 -> Int -> IO (Const a b) # pokeByteOff :: Ptr b0 -> Int -> Const a b -> IO () # peek :: Ptr (Const a b) -> IO (Const a b) # poke :: Ptr (Const a b) -> Const a b -> IO () #
Bits a => Bits (Const a b)	Since: base-4.9.0.0
Instance details Defined in Data.Functor.Const Methods (.&.) :: Const a b -> Const a b -> Const a b # (.\|.) :: Const a b -> Const a b -> Const a b # xor :: Const a b -> Const a b -> Const a b # complement :: Const a b -> Const a b # shift :: Const a b -> Int -> Const a b # rotate :: Const a b -> Int -> Const a b # zeroBits :: Const a b # bit :: Int -> Const a b # setBit :: Const a b -> Int -> Const a b # clearBit :: Const a b -> Int -> Const a b # complementBit :: Const a b -> Int -> Const a b # testBit :: Const a b -> Int -> Bool # bitSizeMaybe :: Const a b -> Maybe Int # bitSize :: Const a b -> Int # isSigned :: Const a b -> Bool # shiftL :: Const a b -> Int -> Const a b # unsafeShiftL :: Const a b -> Int -> Const a b # shiftR :: Const a b -> Int -> Const a b # unsafeShiftR :: Const a b -> Int -> Const a b # rotateL :: Const a b -> Int -> Const a b # rotateR :: Const a b -> Int -> Const a b # popCount :: Const a b -> Int #
FiniteBits a => FiniteBits (Const a b)	Since: base-4.9.0.0
Instance details Defined in Data.Functor.Const Methods finiteBitSize :: Const a b -> Int # countLeadingZeros :: Const a b -> Int # countTrailingZeros :: Const a b -> Int #
NFData a => NFData (Const a b)	Since: deepseq-1.4.0.0
Instance details Defined in Control.DeepSeq Methods rnf :: Const a b -> () #
Hashable a => Hashable (Const a b)
Instance details Defined in Data.Hashable.Class Methods hashWithSalt :: Int -> Const a b -> Int # hash :: Const a b -> Int #
Container (Const a b)
Instance details Defined in Universum.Container.Class Associated Types type Element (Const a b) :: Type # Methods toList :: Const a b -> [Element (Const a b)] # null :: Const a b -> Bool # foldr :: (Element (Const a b) -> b0 -> b0) -> b0 -> Const a b -> b0 # foldl :: (b0 -> Element (Const a b) -> b0) -> b0 -> Const a b -> b0 # foldl' :: (b0 -> Element (Const a b) -> b0) -> b0 -> Const a b -> b0 # length :: Const a b -> Int # elem :: Element (Const a b) -> Const a b -> Bool # maximum :: Const a b -> Element (Const a b) # minimum :: Const a b -> Element (Const a b) # foldMap :: Monoid m => (Element (Const a b) -> m) -> Const a b -> m # fold :: Const a b -> Element (Const a b) # foldr' :: (Element (Const a b) -> b0 -> b0) -> b0 -> Const a b -> b0 # foldr1 :: (Element (Const a b) -> Element (Const a b) -> Element (Const a b)) -> Const a b -> Element (Const a b) # foldl1 :: (Element (Const a b) -> Element (Const a b) -> Element (Const a b)) -> Const a b -> Element (Const a b) # notElem :: Element (Const a b) -> Const a b -> Bool # all :: (Element (Const a b) -> Bool) -> Const a b -> Bool # any :: (Element (Const a b) -> Bool) -> Const a b -> Bool # and :: Const a b -> Bool # or :: Const a b -> Bool # find :: (Element (Const a b) -> Bool) -> Const a b -> Maybe (Element (Const a b)) # safeHead :: Const a b -> Maybe (Element (Const a b)) #
type Rep1 (Const a :: k -> Type)	Since: base-4.9.0.0
Instance details Defined in Data.Functor.Const type Rep1 (Const a :: k -> Type) = D1 (MetaData "Const" "Data.Functor.Const" "base" True) (C1 (MetaCons "Const" PrefixI True) (S1 (MetaSel (Just "getConst") NoSourceUnpackedness NoSourceStrictness DecidedLazy) (Rec0 a)))
type Rep (Const a b)	Since: base-4.9.0.0
Instance details Defined in Data.Functor.Const type Rep (Const a b) = D1 (MetaData "Const" "Data.Functor.Const" "base" True) (C1 (MetaCons "Const" PrefixI True) (S1 (MetaSel (Just "getConst") NoSourceUnpackedness NoSourceStrictness DecidedLazy) (Rec0 a)))
type Element (Const a b)
Instance details Defined in Universum.Container.Class type Element (Const a b) = ElementDefault (Const a b)

minimumBy :: Foldable t => (a -> a -> Ordering) -> t a -> a #

The least element of a non-empty structure with respect to the given comparison function.

maximumBy :: Foldable t => (a -> a -> Ordering) -> t a -> a #

The largest element of a non-empty structure with respect to the given comparison function.

concatMap :: Foldable t => (a -> [b]) -> t a -> [b] #

Map a function over all the elements of a container and concatenate the resulting lists.

concat :: Foldable t => t [a] -> [a] #

The concatenation of all the elements of a container of lists.

foldlM :: (Foldable t, Monad m) => (b -> a -> m b) -> b -> t a -> m b #

Monadic fold over the elements of a structure, associating to the left, i.e. from left to right.

foldrM :: (Foldable t, Monad m) => (a -> b -> m b) -> b -> t a -> m b #

Monadic fold over the elements of a structure, associating to the right, i.e. from right to left.

newtype First a #

Maybe monoid returning the leftmost non-Nothing value.

First a is isomorphic to Alt Maybe a, but precedes it historically.

>>> getFirst (First (Just "hello") <> First Nothing <> First (Just "world"))
Just "hello"

Use of this type is discouraged. Note the following equivalence:

Data.Monoid.First x === Maybe (Data.Semigroup.First x)

In addition to being equivalent in the structural sense, the two also have Monoid instances that behave the same. This type will be marked deprecated in GHC 8.8, and removed in GHC 8.10. Users are advised to use the variant from Data.Semigroup and wrap it in Maybe.

Constructors

First
Fields getFirst :: Maybe a

Instances

Monad First	Since: base-4.8.0.0
Instance details Defined in Data.Monoid Methods (>>=) :: First a -> (a -> First b) -> First b # (>>) :: First a -> First b -> First b # return :: a -> First a # fail :: String -> First a #
Functor First	Since: base-4.8.0.0
Instance details Defined in Data.Monoid Methods fmap :: (a -> b) -> First a -> First b # (<$) :: a -> First b -> First a #
Applicative First	Since: base-4.8.0.0
Instance details Defined in Data.Monoid Methods pure :: a -> First a # (<>) :: First (a -> b) -> First a -> First b # liftA2 :: (a -> b -> c) -> First a -> First b -> First c # (>) :: First a -> First b -> First b # (<*) :: First a -> First b -> First a #
Foldable First	Since: base-4.8.0.0
Instance details Defined in Data.Foldable Methods fold :: Monoid m => First m -> m # foldMap :: Monoid m => (a -> m) -> First a -> m # foldr :: (a -> b -> b) -> b -> First a -> b # foldr' :: (a -> b -> b) -> b -> First a -> b # foldl :: (b -> a -> b) -> b -> First a -> b # foldl' :: (b -> a -> b) -> b -> First a -> b # foldr1 :: (a -> a -> a) -> First a -> a # foldl1 :: (a -> a -> a) -> First a -> a # toList :: First a -> [a] # null :: First a -> Bool # length :: First a -> Int # elem :: Eq a => a -> First a -> Bool # maximum :: Ord a => First a -> a # minimum :: Ord a => First a -> a # sum :: Num a => First a -> a # product :: Num a => First a -> a #
Traversable First	Since: base-4.8.0.0
Instance details Defined in Data.Traversable Methods traverse :: Applicative f => (a -> f b) -> First a -> f (First b) # sequenceA :: Applicative f => First (f a) -> f (First a) # mapM :: Monad m => (a -> m b) -> First a -> m (First b) # sequence :: Monad m => First (m a) -> m (First a) #
NFData1 First	Since: deepseq-1.4.3.0
Instance details Defined in Control.DeepSeq Methods liftRnf :: (a -> ()) -> First a -> () #
Eq a => Eq (First a)	Since: base-2.1
Instance details Defined in Data.Monoid Methods (==) :: First a -> First a -> Bool # (/=) :: First a -> First a -> Bool #
Ord a => Ord (First a)	Since: base-2.1
Instance details Defined in Data.Monoid Methods compare :: First a -> First a -> Ordering # (<) :: First a -> First a -> Bool # (<=) :: First a -> First a -> Bool # (>) :: First a -> First a -> Bool # (>=) :: First a -> First a -> Bool # max :: First a -> First a -> First a # min :: First a -> First a -> First a #
Read a => Read (First a)	Since: base-2.1
Instance details Defined in Data.Monoid Methods readsPrec :: Int -> ReadS (First a) # readList :: ReadS [First a] # readPrec :: ReadPrec (First a) # readListPrec :: ReadPrec [First a] #
Show a => Show (First a)	Since: base-2.1
Instance details Defined in Data.Monoid Methods showsPrec :: Int -> First a -> ShowS # show :: First a -> String # showList :: [First a] -> ShowS #
Generic (First a)
Instance details Defined in Data.Monoid Associated Types type Rep (First a) :: Type -> Type # Methods from :: First a -> Rep (First a) x # to :: Rep (First a) x -> First a #
Semigroup (First a)	Since: base-4.9.0.0
Instance details Defined in Data.Monoid Methods (<>) :: First a -> First a -> First a # sconcat :: NonEmpty (First a) -> First a # stimes :: Integral b => b -> First a -> First a #
Monoid (First a)	Since: base-2.1
Instance details Defined in Data.Monoid Methods mempty :: First a # mappend :: First a -> First a -> First a # mconcat :: [First a] -> First a #
NFData a => NFData (First a)	Since: deepseq-1.4.0.0
Instance details Defined in Control.DeepSeq Methods rnf :: First a -> () #
Container (First a)
Instance details Defined in Universum.Container.Class Associated Types type Element (First a) :: Type # Methods toList :: First a -> [Element (First a)] # null :: First a -> Bool # foldr :: (Element (First a) -> b -> b) -> b -> First a -> b # foldl :: (b -> Element (First a) -> b) -> b -> First a -> b # foldl' :: (b -> Element (First a) -> b) -> b -> First a -> b # length :: First a -> Int # elem :: Element (First a) -> First a -> Bool # maximum :: First a -> Element (First a) # minimum :: First a -> Element (First a) # foldMap :: Monoid m => (Element (First a) -> m) -> First a -> m # fold :: First a -> Element (First a) # foldr' :: (Element (First a) -> b -> b) -> b -> First a -> b # foldr1 :: (Element (First a) -> Element (First a) -> Element (First a)) -> First a -> Element (First a) # foldl1 :: (Element (First a) -> Element (First a) -> Element (First a)) -> First a -> Element (First a) # notElem :: Element (First a) -> First a -> Bool # all :: (Element (First a) -> Bool) -> First a -> Bool # any :: (Element (First a) -> Bool) -> First a -> Bool # and :: First a -> Bool # or :: First a -> Bool # find :: (Element (First a) -> Bool) -> First a -> Maybe (Element (First a)) # safeHead :: First a -> Maybe (Element (First a)) #
Generic1 First
Instance details Defined in Data.Monoid Associated Types type Rep1 First :: k -> Type # Methods from1 :: First a -> Rep1 First a # to1 :: Rep1 First a -> First a #
type Rep (First a)	Since: base-4.7.0.0
Instance details Defined in Data.Monoid type Rep (First a) = D1 (MetaData "First" "Data.Monoid" "base" True) (C1 (MetaCons "First" PrefixI True) (S1 (MetaSel (Just "getFirst") NoSourceUnpackedness NoSourceStrictness DecidedLazy) (Rec0 (Maybe a))))
type Element (First a)
Instance details Defined in Universum.Container.Class type Element (First a) = ElementDefault (First a)
type Rep1 First	Since: base-4.7.0.0
Instance details Defined in Data.Monoid type Rep1 First = D1 (MetaData "First" "Data.Monoid" "base" True) (C1 (MetaCons "First" PrefixI True) (S1 (MetaSel (Just "getFirst") NoSourceUnpackedness NoSourceStrictness DecidedLazy) (Rec1 Maybe)))

newtype Last a #

Maybe monoid returning the rightmost non-Nothing value.

Last a is isomorphic to Dual (First a), and thus to Dual (Alt Maybe a)

>>> getLast (Last (Just "hello") <> Last Nothing <> Last (Just "world"))
Just "world"

Use of this type is discouraged. Note the following equivalence:

Data.Monoid.Last x === Maybe (Data.Semigroup.Last x)

In addition to being equivalent in the structural sense, the two also have Monoid instances that behave the same. This type will be marked deprecated in GHC 8.8, and removed in GHC 8.10. Users are advised to use the variant from Data.Semigroup and wrap it in Maybe.

Constructors

Last
Fields getLast :: Maybe a

Instances

Monad Last	Since: base-4.8.0.0
Instance details Defined in Data.Monoid Methods (>>=) :: Last a -> (a -> Last b) -> Last b # (>>) :: Last a -> Last b -> Last b # return :: a -> Last a # fail :: String -> Last a #
Functor Last	Since: base-4.8.0.0
Instance details Defined in Data.Monoid Methods fmap :: (a -> b) -> Last a -> Last b # (<$) :: a -> Last b -> Last a #
Applicative Last	Since: base-4.8.0.0
Instance details Defined in Data.Monoid Methods pure :: a -> Last a # (<>) :: Last (a -> b) -> Last a -> Last b # liftA2 :: (a -> b -> c) -> Last a -> Last b -> Last c # (>) :: Last a -> Last b -> Last b # (<*) :: Last a -> Last b -> Last a #
Foldable Last	Since: base-4.8.0.0
Instance details Defined in Data.Foldable Methods fold :: Monoid m => Last m -> m # foldMap :: Monoid m => (a -> m) -> Last a -> m # foldr :: (a -> b -> b) -> b -> Last a -> b # foldr' :: (a -> b -> b) -> b -> Last a -> b # foldl :: (b -> a -> b) -> b -> Last a -> b # foldl' :: (b -> a -> b) -> b -> Last a -> b # foldr1 :: (a -> a -> a) -> Last a -> a # foldl1 :: (a -> a -> a) -> Last a -> a # toList :: Last a -> [a] # null :: Last a -> Bool # length :: Last a -> Int # elem :: Eq a => a -> Last a -> Bool # maximum :: Ord a => Last a -> a # minimum :: Ord a => Last a -> a # sum :: Num a => Last a -> a # product :: Num a => Last a -> a #
Traversable Last	Since: base-4.8.0.0
Instance details Defined in Data.Traversable Methods traverse :: Applicative f => (a -> f b) -> Last a -> f (Last b) # sequenceA :: Applicative f => Last (f a) -> f (Last a) # mapM :: Monad m => (a -> m b) -> Last a -> m (Last b) # sequence :: Monad m => Last (m a) -> m (Last a) #
NFData1 Last	Since: deepseq-1.4.3.0
Instance details Defined in Control.DeepSeq Methods liftRnf :: (a -> ()) -> Last a -> () #
Eq a => Eq (Last a)	Since: base-2.1
Instance details Defined in Data.Monoid Methods (==) :: Last a -> Last a -> Bool # (/=) :: Last a -> Last a -> Bool #
Ord a => Ord (Last a)	Since: base-2.1
Instance details Defined in Data.Monoid Methods compare :: Last a -> Last a -> Ordering # (<) :: Last a -> Last a -> Bool # (<=) :: Last a -> Last a -> Bool # (>) :: Last a -> Last a -> Bool # (>=) :: Last a -> Last a -> Bool # max :: Last a -> Last a -> Last a # min :: Last a -> Last a -> Last a #
Read a => Read (Last a)	Since: base-2.1
Instance details Defined in Data.Monoid Methods readsPrec :: Int -> ReadS (Last a) # readList :: ReadS [Last a] # readPrec :: ReadPrec (Last a) # readListPrec :: ReadPrec [Last a] #
Show a => Show (Last a)	Since: base-2.1
Instance details Defined in Data.Monoid Methods showsPrec :: Int -> Last a -> ShowS # show :: Last a -> String # showList :: [Last a] -> ShowS #
Generic (Last a)
Instance details Defined in Data.Monoid Associated Types type Rep (Last a) :: Type -> Type # Methods from :: Last a -> Rep (Last a) x # to :: Rep (Last a) x -> Last a #
Semigroup (Last a)	Since: base-4.9.0.0
Instance details Defined in Data.Monoid Methods (<>) :: Last a -> Last a -> Last a # sconcat :: NonEmpty (Last a) -> Last a # stimes :: Integral b => b -> Last a -> Last a #
Monoid (Last a)	Since: base-2.1
Instance details Defined in Data.Monoid Methods mempty :: Last a # mappend :: Last a -> Last a -> Last a # mconcat :: [Last a] -> Last a #
NFData a => NFData (Last a)	Since: deepseq-1.4.0.0
Instance details Defined in Control.DeepSeq Methods rnf :: Last a -> () #
Container (Last a)
Instance details Defined in Universum.Container.Class Associated Types type Element (Last a) :: Type # Methods toList :: Last a -> [Element (Last a)] # null :: Last a -> Bool # foldr :: (Element (Last a) -> b -> b) -> b -> Last a -> b # foldl :: (b -> Element (Last a) -> b) -> b -> Last a -> b # foldl' :: (b -> Element (Last a) -> b) -> b -> Last a -> b # length :: Last a -> Int # elem :: Element (Last a) -> Last a -> Bool # maximum :: Last a -> Element (Last a) # minimum :: Last a -> Element (Last a) # foldMap :: Monoid m => (Element (Last a) -> m) -> Last a -> m # fold :: Last a -> Element (Last a) # foldr' :: (Element (Last a) -> b -> b) -> b -> Last a -> b # foldr1 :: (Element (Last a) -> Element (Last a) -> Element (Last a)) -> Last a -> Element (Last a) # foldl1 :: (Element (Last a) -> Element (Last a) -> Element (Last a)) -> Last a -> Element (Last a) # notElem :: Element (Last a) -> Last a -> Bool # all :: (Element (Last a) -> Bool) -> Last a -> Bool # any :: (Element (Last a) -> Bool) -> Last a -> Bool # and :: Last a -> Bool # or :: Last a -> Bool # find :: (Element (Last a) -> Bool) -> Last a -> Maybe (Element (Last a)) # safeHead :: Last a -> Maybe (Element (Last a)) #
Generic1 Last
Instance details Defined in Data.Monoid Associated Types type Rep1 Last :: k -> Type # Methods from1 :: Last a -> Rep1 Last a # to1 :: Rep1 Last a -> Last a #
type Rep (Last a)	Since: base-4.7.0.0
Instance details Defined in Data.Monoid type Rep (Last a) = D1 (MetaData "Last" "Data.Monoid" "base" True) (C1 (MetaCons "Last" PrefixI True) (S1 (MetaSel (Just "getLast") NoSourceUnpackedness NoSourceStrictness DecidedLazy) (Rec0 (Maybe a))))
type Element (Last a)
Instance details Defined in Universum.Container.Class type Element (Last a) = ElementDefault (Last a)
type Rep1 Last	Since: base-4.7.0.0
Instance details Defined in Data.Monoid type Rep1 Last = D1 (MetaData "Last" "Data.Monoid" "base" True) (C1 (MetaCons "Last" PrefixI True) (S1 (MetaSel (Just "getLast") NoSourceUnpackedness NoSourceStrictness DecidedLazy) (Rec1 Maybe)))

stimesMonoid :: (Integral b, Monoid a) => b -> a -> a #

This is a valid definition of stimes for a Monoid.

Unlike the default definition of stimes, it is defined for 0 and so it should be preferred where possible.

stimesIdempotent :: Integral b => b -> a -> a #

This is a valid definition of stimes for an idempotent Semigroup.

When x <> x = x, this definition should be preferred, because it works in O(1) rather than O(log n).

newtype Dual a #

The dual of a Monoid, obtained by swapping the arguments of mappend.

>>> getDual (mappend (Dual "Hello") (Dual "World"))
"WorldHello"

Constructors

Dual
Fields getDual :: a

Instances

Monad Dual	Since: base-4.8.0.0
Instance details Defined in Data.Semigroup.Internal Methods (>>=) :: Dual a -> (a -> Dual b) -> Dual b # (>>) :: Dual a -> Dual b -> Dual b # return :: a -> Dual a # fail :: String -> Dual a #
Functor Dual	Since: base-4.8.0.0
Instance details Defined in Data.Semigroup.Internal Methods fmap :: (a -> b) -> Dual a -> Dual b # (<$) :: a -> Dual b -> Dual a #
Applicative Dual	Since: base-4.8.0.0
Instance details Defined in Data.Semigroup.Internal Methods pure :: a -> Dual a # (<>) :: Dual (a -> b) -> Dual a -> Dual b # liftA2 :: (a -> b -> c) -> Dual a -> Dual b -> Dual c # (>) :: Dual a -> Dual b -> Dual b # (<*) :: Dual a -> Dual b -> Dual a #
Foldable Dual	Since: base-4.8.0.0
Instance details Defined in Data.Foldable Methods fold :: Monoid m => Dual m -> m # foldMap :: Monoid m => (a -> m) -> Dual a -> m # foldr :: (a -> b -> b) -> b -> Dual a -> b # foldr' :: (a -> b -> b) -> b -> Dual a -> b # foldl :: (b -> a -> b) -> b -> Dual a -> b # foldl' :: (b -> a -> b) -> b -> Dual a -> b # foldr1 :: (a -> a -> a) -> Dual a -> a # foldl1 :: (a -> a -> a) -> Dual a -> a # toList :: Dual a -> [a] # null :: Dual a -> Bool # length :: Dual a -> Int # elem :: Eq a => a -> Dual a -> Bool # maximum :: Ord a => Dual a -> a # minimum :: Ord a => Dual a -> a # sum :: Num a => Dual a -> a # product :: Num a => Dual a -> a #
Traversable Dual	Since: base-4.8.0.0
Instance details Defined in Data.Traversable Methods traverse :: Applicative f => (a -> f b) -> Dual a -> f (Dual b) # sequenceA :: Applicative f => Dual (f a) -> f (Dual a) # mapM :: Monad m => (a -> m b) -> Dual a -> m (Dual b) # sequence :: Monad m => Dual (m a) -> m (Dual a) #
NFData1 Dual	Since: deepseq-1.4.3.0
Instance details Defined in Control.DeepSeq Methods liftRnf :: (a -> ()) -> Dual a -> () #
Bounded a => Bounded (Dual a)	Since: base-2.1
Instance details Defined in Data.Semigroup.Internal Methods minBound :: Dual a # maxBound :: Dual a #
Eq a => Eq (Dual a)	Since: base-2.1
Instance details Defined in Data.Semigroup.Internal Methods (==) :: Dual a -> Dual a -> Bool # (/=) :: Dual a -> Dual a -> Bool #
Ord a => Ord (Dual a)	Since: base-2.1
Instance details Defined in Data.Semigroup.Internal Methods compare :: Dual a -> Dual a -> Ordering # (<) :: Dual a -> Dual a -> Bool # (<=) :: Dual a -> Dual a -> Bool # (>) :: Dual a -> Dual a -> Bool # (>=) :: Dual a -> Dual a -> Bool # max :: Dual a -> Dual a -> Dual a # min :: Dual a -> Dual a -> Dual a #
Read a => Read (Dual a)	Since: base-2.1
Instance details Defined in Data.Semigroup.Internal Methods readsPrec :: Int -> ReadS (Dual a) # readList :: ReadS [Dual a] # readPrec :: ReadPrec (Dual a) # readListPrec :: ReadPrec [Dual a] #
Show a => Show (Dual a)	Since: base-2.1
Instance details Defined in Data.Semigroup.Internal Methods showsPrec :: Int -> Dual a -> ShowS # show :: Dual a -> String # showList :: [Dual a] -> ShowS #
Generic (Dual a)
Instance details Defined in Data.Semigroup.Internal Associated Types type Rep (Dual a) :: Type -> Type # Methods from :: Dual a -> Rep (Dual a) x # to :: Rep (Dual a) x -> Dual a #
Semigroup a => Semigroup (Dual a)	Since: base-4.9.0.0
Instance details Defined in Data.Semigroup.Internal Methods (<>) :: Dual a -> Dual a -> Dual a # sconcat :: NonEmpty (Dual a) -> Dual a # stimes :: Integral b => b -> Dual a -> Dual a #
Monoid a => Monoid (Dual a)	Since: base-2.1
Instance details Defined in Data.Semigroup.Internal Methods mempty :: Dual a # mappend :: Dual a -> Dual a -> Dual a # mconcat :: [Dual a] -> Dual a #
NFData a => NFData (Dual a)	Since: deepseq-1.4.0.0
Instance details Defined in Control.DeepSeq Methods rnf :: Dual a -> () #
Container (Dual a)
Instance details Defined in Universum.Container.Class Associated Types type Element (Dual a) :: Type # Methods toList :: Dual a -> [Element (Dual a)] # null :: Dual a -> Bool # foldr :: (Element (Dual a) -> b -> b) -> b -> Dual a -> b # foldl :: (b -> Element (Dual a) -> b) -> b -> Dual a -> b # foldl' :: (b -> Element (Dual a) -> b) -> b -> Dual a -> b # length :: Dual a -> Int # elem :: Element (Dual a) -> Dual a -> Bool # maximum :: Dual a -> Element (Dual a) # minimum :: Dual a -> Element (Dual a) # foldMap :: Monoid m => (Element (Dual a) -> m) -> Dual a -> m # fold :: Dual a -> Element (Dual a) # foldr' :: (Element (Dual a) -> b -> b) -> b -> Dual a -> b # foldr1 :: (Element (Dual a) -> Element (Dual a) -> Element (Dual a)) -> Dual a -> Element (Dual a) # foldl1 :: (Element (Dual a) -> Element (Dual a) -> Element (Dual a)) -> Dual a -> Element (Dual a) # notElem :: Element (Dual a) -> Dual a -> Bool # all :: (Element (Dual a) -> Bool) -> Dual a -> Bool # any :: (Element (Dual a) -> Bool) -> Dual a -> Bool # and :: Dual a -> Bool # or :: Dual a -> Bool # find :: (Element (Dual a) -> Bool) -> Dual a -> Maybe (Element (Dual a)) # safeHead :: Dual a -> Maybe (Element (Dual a)) #
Generic1 Dual
Instance details Defined in Data.Semigroup.Internal Associated Types type Rep1 Dual :: k -> Type # Methods from1 :: Dual a -> Rep1 Dual a # to1 :: Rep1 Dual a -> Dual a #
type Rep (Dual a)	Since: base-4.7.0.0
Instance details Defined in Data.Semigroup.Internal type Rep (Dual a) = D1 (MetaData "Dual" "Data.Semigroup.Internal" "base" True) (C1 (MetaCons "Dual" PrefixI True) (S1 (MetaSel (Just "getDual") NoSourceUnpackedness NoSourceStrictness DecidedLazy) (Rec0 a)))
type Element (Dual a)
Instance details Defined in Universum.Container.Class type Element (Dual a) = ElementDefault (Dual a)
type Rep1 Dual	Since: base-4.7.0.0
Instance details Defined in Data.Semigroup.Internal type Rep1 Dual = D1 (MetaData "Dual" "Data.Semigroup.Internal" "base" True) (C1 (MetaCons "Dual" PrefixI True) (S1 (MetaSel (Just "getDual") NoSourceUnpackedness NoSourceStrictness DecidedLazy) Par1))

newtype Endo a #

The monoid of endomorphisms under composition.

>>> let computation = Endo ("Hello, " ++) <> Endo (++ "!")
>>> appEndo computation "Haskell"
"Hello, Haskell!"

Constructors

Endo
Fields appEndo :: a -> a

Instances

Generic (Endo a)
Instance details Defined in Data.Semigroup.Internal Associated Types type Rep (Endo a) :: Type -> Type # Methods from :: Endo a -> Rep (Endo a) x # to :: Rep (Endo a) x -> Endo a #
Semigroup (Endo a)	Since: base-4.9.0.0
Instance details Defined in Data.Semigroup.Internal Methods (<>) :: Endo a -> Endo a -> Endo a # sconcat :: NonEmpty (Endo a) -> Endo a # stimes :: Integral b => b -> Endo a -> Endo a #
Monoid (Endo a)	Since: base-2.1
Instance details Defined in Data.Semigroup.Internal Methods mempty :: Endo a # mappend :: Endo a -> Endo a -> Endo a # mconcat :: [Endo a] -> Endo a #
type Rep (Endo a)	Since: base-4.7.0.0
Instance details Defined in Data.Semigroup.Internal type Rep (Endo a) = D1 (MetaData "Endo" "Data.Semigroup.Internal" "base" True) (C1 (MetaCons "Endo" PrefixI True) (S1 (MetaSel (Just "appEndo") NoSourceUnpackedness NoSourceStrictness DecidedLazy) (Rec0 (a -> a))))

newtype All #

Boolean monoid under conjunction (&&).

>>> getAll (All True <> mempty <> All False)
False

>>> getAll (mconcat (map (\x -> All (even x)) [2,4,6,7,8]))
False

Constructors

All
Fields getAll :: Bool

Instances

Bounded All	Since: base-2.1
Instance details Defined in Data.Semigroup.Internal Methods minBound :: All # maxBound :: All #
Eq All	Since: base-2.1
Instance details Defined in Data.Semigroup.Internal Methods (==) :: All -> All -> Bool # (/=) :: All -> All -> Bool #
Ord All	Since: base-2.1
Instance details Defined in Data.Semigroup.Internal Methods compare :: All -> All -> Ordering # (<) :: All -> All -> Bool # (<=) :: All -> All -> Bool # (>) :: All -> All -> Bool # (>=) :: All -> All -> Bool # max :: All -> All -> All # min :: All -> All -> All #
Read All	Since: base-2.1
Instance details Defined in Data.Semigroup.Internal Methods readsPrec :: Int -> ReadS All # readList :: ReadS [All] # readPrec :: ReadPrec All # readListPrec :: ReadPrec [All] #
Show All	Since: base-2.1
Instance details Defined in Data.Semigroup.Internal Methods showsPrec :: Int -> All -> ShowS # show :: All -> String # showList :: [All] -> ShowS #
Generic All
Instance details Defined in Data.Semigroup.Internal Associated Types type Rep All :: Type -> Type # Methods from :: All -> Rep All x # to :: Rep All x -> All #
Semigroup All	Since: base-4.9.0.0
Instance details Defined in Data.Semigroup.Internal Methods (<>) :: All -> All -> All # sconcat :: NonEmpty All -> All # stimes :: Integral b => b -> All -> All #
Monoid All	Since: base-2.1
Instance details Defined in Data.Semigroup.Internal Methods mempty :: All # mappend :: All -> All -> All # mconcat :: [All] -> All #
NFData All	Since: deepseq-1.4.0.0
Instance details Defined in Control.DeepSeq Methods rnf :: All -> () #
type Rep All	Since: base-4.7.0.0
Instance details Defined in Data.Semigroup.Internal type Rep All = D1 (MetaData "All" "Data.Semigroup.Internal" "base" True) (C1 (MetaCons "All" PrefixI True) (S1 (MetaSel (Just "getAll") NoSourceUnpackedness NoSourceStrictness DecidedLazy) (Rec0 Bool)))

newtype Any #

Boolean monoid under disjunction (||).

>>> getAny (Any True <> mempty <> Any False)
True

>>> getAny (mconcat (map (\x -> Any (even x)) [2,4,6,7,8]))
True

Constructors

Any
Fields getAny :: Bool

Instances

Bounded Any	Since: base-2.1
Instance details Defined in Data.Semigroup.Internal Methods minBound :: Any # maxBound :: Any #
Eq Any	Since: base-2.1
Instance details Defined in Data.Semigroup.Internal Methods (==) :: Any -> Any -> Bool # (/=) :: Any -> Any -> Bool #
Ord Any	Since: base-2.1
Instance details Defined in Data.Semigroup.Internal Methods compare :: Any -> Any -> Ordering # (<) :: Any -> Any -> Bool # (<=) :: Any -> Any -> Bool # (>) :: Any -> Any -> Bool # (>=) :: Any -> Any -> Bool # max :: Any -> Any -> Any # min :: Any -> Any -> Any #
Read Any	Since: base-2.1
Instance details Defined in Data.Semigroup.Internal Methods readsPrec :: Int -> ReadS Any # readList :: ReadS [Any] # readPrec :: ReadPrec Any # readListPrec :: ReadPrec [Any] #
Show Any	Since: base-2.1
Instance details Defined in Data.Semigroup.Internal Methods showsPrec :: Int -> Any -> ShowS # show :: Any -> String # showList :: [Any] -> ShowS #
Generic Any
Instance details Defined in Data.Semigroup.Internal Associated Types type Rep Any :: Type -> Type # Methods from :: Any -> Rep Any x # to :: Rep Any x -> Any #
Semigroup Any	Since: base-4.9.0.0
Instance details Defined in Data.Semigroup.Internal Methods (<>) :: Any -> Any -> Any # sconcat :: NonEmpty Any -> Any # stimes :: Integral b => b -> Any -> Any #
Monoid Any	Since: base-2.1
Instance details Defined in Data.Semigroup.Internal Methods mempty :: Any # mappend :: Any -> Any -> Any # mconcat :: [Any] -> Any #
NFData Any	Since: deepseq-1.4.0.0
Instance details Defined in Control.DeepSeq Methods rnf :: Any -> () #
type Rep Any	Since: base-4.7.0.0
Instance details Defined in Data.Semigroup.Internal type Rep Any = D1 (MetaData "Any" "Data.Semigroup.Internal" "base" True) (C1 (MetaCons "Any" PrefixI True) (S1 (MetaSel (Just "getAny") NoSourceUnpackedness NoSourceStrictness DecidedLazy) (Rec0 Bool)))

newtype Sum a #

Monoid under addition.

>>> getSum (Sum 1 <> Sum 2 <> mempty)
3

Constructors

Sum
Fields getSum :: a

Instances

Monad Sum	Since: base-4.8.0.0
Instance details Defined in Data.Semigroup.Internal Methods (>>=) :: Sum a -> (a -> Sum b) -> Sum b # (>>) :: Sum a -> Sum b -> Sum b # return :: a -> Sum a # fail :: String -> Sum a #
Functor Sum	Since: base-4.8.0.0
Instance details Defined in Data.Semigroup.Internal Methods fmap :: (a -> b) -> Sum a -> Sum b # (<$) :: a -> Sum b -> Sum a #
Applicative Sum	Since: base-4.8.0.0
Instance details Defined in Data.Semigroup.Internal Methods pure :: a -> Sum a # (<>) :: Sum (a -> b) -> Sum a -> Sum b # liftA2 :: (a -> b -> c) -> Sum a -> Sum b -> Sum c # (>) :: Sum a -> Sum b -> Sum b # (<*) :: Sum a -> Sum b -> Sum a #
Foldable Sum	Since: base-4.8.0.0
Instance details Defined in Data.Foldable Methods fold :: Monoid m => Sum m -> m # foldMap :: Monoid m => (a -> m) -> Sum a -> m # foldr :: (a -> b -> b) -> b -> Sum a -> b # foldr' :: (a -> b -> b) -> b -> Sum a -> b # foldl :: (b -> a -> b) -> b -> Sum a -> b # foldl' :: (b -> a -> b) -> b -> Sum a -> b # foldr1 :: (a -> a -> a) -> Sum a -> a # foldl1 :: (a -> a -> a) -> Sum a -> a # toList :: Sum a -> [a] # null :: Sum a -> Bool # length :: Sum a -> Int # elem :: Eq a => a -> Sum a -> Bool # maximum :: Ord a => Sum a -> a # minimum :: Ord a => Sum a -> a # sum :: Num a => Sum a -> a # product :: Num a => Sum a -> a #
Traversable Sum	Since: base-4.8.0.0
Instance details Defined in Data.Traversable Methods traverse :: Applicative f => (a -> f b) -> Sum a -> f (Sum b) # sequenceA :: Applicative f => Sum (f a) -> f (Sum a) # mapM :: Monad m => (a -> m b) -> Sum a -> m (Sum b) # sequence :: Monad m => Sum (m a) -> m (Sum a) #
NFData1 Sum	Since: deepseq-1.4.3.0
Instance details Defined in Control.DeepSeq Methods liftRnf :: (a -> ()) -> Sum a -> () #
Bounded a => Bounded (Sum a)	Since: base-2.1
Instance details Defined in Data.Semigroup.Internal Methods minBound :: Sum a # maxBound :: Sum a #
Eq a => Eq (Sum a)	Since: base-2.1
Instance details Defined in Data.Semigroup.Internal Methods (==) :: Sum a -> Sum a -> Bool # (/=) :: Sum a -> Sum a -> Bool #
Num a => Num (Sum a)	Since: base-4.7.0.0
Instance details Defined in Data.Semigroup.Internal Methods (+) :: Sum a -> Sum a -> Sum a # (-) :: Sum a -> Sum a -> Sum a # (*) :: Sum a -> Sum a -> Sum a # negate :: Sum a -> Sum a # abs :: Sum a -> Sum a # signum :: Sum a -> Sum a # fromInteger :: Integer -> Sum a #
Ord a => Ord (Sum a)	Since: base-2.1
Instance details Defined in Data.Semigroup.Internal Methods compare :: Sum a -> Sum a -> Ordering # (<) :: Sum a -> Sum a -> Bool # (<=) :: Sum a -> Sum a -> Bool # (>) :: Sum a -> Sum a -> Bool # (>=) :: Sum a -> Sum a -> Bool # max :: Sum a -> Sum a -> Sum a # min :: Sum a -> Sum a -> Sum a #
Read a => Read (Sum a)	Since: base-2.1
Instance details Defined in Data.Semigroup.Internal Methods readsPrec :: Int -> ReadS (Sum a) # readList :: ReadS [Sum a] # readPrec :: ReadPrec (Sum a) # readListPrec :: ReadPrec [Sum a] #
Show a => Show (Sum a)	Since: base-2.1
Instance details Defined in Data.Semigroup.Internal Methods showsPrec :: Int -> Sum a -> ShowS # show :: Sum a -> String # showList :: [Sum a] -> ShowS #
Generic (Sum a)
Instance details Defined in Data.Semigroup.Internal Associated Types type Rep (Sum a) :: Type -> Type # Methods from :: Sum a -> Rep (Sum a) x # to :: Rep (Sum a) x -> Sum a #
Num a => Semigroup (Sum a)	Since: base-4.9.0.0
Instance details Defined in Data.Semigroup.Internal Methods (<>) :: Sum a -> Sum a -> Sum a # sconcat :: NonEmpty (Sum a) -> Sum a # stimes :: Integral b => b -> Sum a -> Sum a #
Num a => Monoid (Sum a)	Since: base-2.1
Instance details Defined in Data.Semigroup.Internal Methods mempty :: Sum a # mappend :: Sum a -> Sum a -> Sum a # mconcat :: [Sum a] -> Sum a #
NFData a => NFData (Sum a)	Since: deepseq-1.4.0.0
Instance details Defined in Control.DeepSeq Methods rnf :: Sum a -> () #
Container (Sum a)
Instance details Defined in Universum.Container.Class Associated Types type Element (Sum a) :: Type # Methods toList :: Sum a -> [Element (Sum a)] # null :: Sum a -> Bool # foldr :: (Element (Sum a) -> b -> b) -> b -> Sum a -> b # foldl :: (b -> Element (Sum a) -> b) -> b -> Sum a -> b # foldl' :: (b -> Element (Sum a) -> b) -> b -> Sum a -> b # length :: Sum a -> Int # elem :: Element (Sum a) -> Sum a -> Bool # maximum :: Sum a -> Element (Sum a) # minimum :: Sum a -> Element (Sum a) # foldMap :: Monoid m => (Element (Sum a) -> m) -> Sum a -> m # fold :: Sum a -> Element (Sum a) # foldr' :: (Element (Sum a) -> b -> b) -> b -> Sum a -> b # foldr1 :: (Element (Sum a) -> Element (Sum a) -> Element (Sum a)) -> Sum a -> Element (Sum a) # foldl1 :: (Element (Sum a) -> Element (Sum a) -> Element (Sum a)) -> Sum a -> Element (Sum a) # notElem :: Element (Sum a) -> Sum a -> Bool # all :: (Element (Sum a) -> Bool) -> Sum a -> Bool # any :: (Element (Sum a) -> Bool) -> Sum a -> Bool # and :: Sum a -> Bool # or :: Sum a -> Bool # find :: (Element (Sum a) -> Bool) -> Sum a -> Maybe (Element (Sum a)) # safeHead :: Sum a -> Maybe (Element (Sum a)) #
Generic1 Sum
Instance details Defined in Data.Semigroup.Internal Associated Types type Rep1 Sum :: k -> Type # Methods from1 :: Sum a -> Rep1 Sum a # to1 :: Rep1 Sum a -> Sum a #
type Rep (Sum a)	Since: base-4.7.0.0
Instance details Defined in Data.Semigroup.Internal type Rep (Sum a) = D1 (MetaData "Sum" "Data.Semigroup.Internal" "base" True) (C1 (MetaCons "Sum" PrefixI True) (S1 (MetaSel (Just "getSum") NoSourceUnpackedness NoSourceStrictness DecidedLazy) (Rec0 a)))
type Element (Sum a)
Instance details Defined in Universum.Container.Class type Element (Sum a) = ElementDefault (Sum a)
type Rep1 Sum	Since: base-4.7.0.0
Instance details Defined in Data.Semigroup.Internal type Rep1 Sum = D1 (MetaData "Sum" "Data.Semigroup.Internal" "base" True) (C1 (MetaCons "Sum" PrefixI True) (S1 (MetaSel (Just "getSum") NoSourceUnpackedness NoSourceStrictness DecidedLazy) Par1))

newtype Product a #

Monoid under multiplication.

>>> getProduct (Product 3 <> Product 4 <> mempty)
12

Constructors

Product
Fields getProduct :: a

Instances

Monad Product	Since: base-4.8.0.0
Instance details Defined in Data.Semigroup.Internal Methods (>>=) :: Product a -> (a -> Product b) -> Product b # (>>) :: Product a -> Product b -> Product b # return :: a -> Product a # fail :: String -> Product a #
Functor Product	Since: base-4.8.0.0
Instance details Defined in Data.Semigroup.Internal Methods fmap :: (a -> b) -> Product a -> Product b # (<$) :: a -> Product b -> Product a #
Applicative Product	Since: base-4.8.0.0
Instance details Defined in Data.Semigroup.Internal Methods pure :: a -> Product a # (<>) :: Product (a -> b) -> Product a -> Product b # liftA2 :: (a -> b -> c) -> Product a -> Product b -> Product c # (>) :: Product a -> Product b -> Product b # (<*) :: Product a -> Product b -> Product a #
Foldable Product	Since: base-4.8.0.0
Instance details Defined in Data.Foldable Methods fold :: Monoid m => Product m -> m # foldMap :: Monoid m => (a -> m) -> Product a -> m # foldr :: (a -> b -> b) -> b -> Product a -> b # foldr' :: (a -> b -> b) -> b -> Product a -> b # foldl :: (b -> a -> b) -> b -> Product a -> b # foldl' :: (b -> a -> b) -> b -> Product a -> b # foldr1 :: (a -> a -> a) -> Product a -> a # foldl1 :: (a -> a -> a) -> Product a -> a # toList :: Product a -> [a] # null :: Product a -> Bool # length :: Product a -> Int # elem :: Eq a => a -> Product a -> Bool # maximum :: Ord a => Product a -> a # minimum :: Ord a => Product a -> a # sum :: Num a => Product a -> a # product :: Num a => Product a -> a #
Traversable Product	Since: base-4.8.0.0
Instance details Defined in Data.Traversable Methods traverse :: Applicative f => (a -> f b) -> Product a -> f (Product b) # sequenceA :: Applicative f => Product (f a) -> f (Product a) # mapM :: Monad m => (a -> m b) -> Product a -> m (Product b) # sequence :: Monad m => Product (m a) -> m (Product a) #
NFData1 Product	Since: deepseq-1.4.3.0
Instance details Defined in Control.DeepSeq Methods liftRnf :: (a -> ()) -> Product a -> () #
Bounded a => Bounded (Product a)	Since: base-2.1
Instance details Defined in Data.Semigroup.Internal Methods minBound :: Product a # maxBound :: Product a #
Eq a => Eq (Product a)	Since: base-2.1
Instance details Defined in Data.Semigroup.Internal Methods (==) :: Product a -> Product a -> Bool # (/=) :: Product a -> Product a -> Bool #
Num a => Num (Product a)	Since: base-4.7.0.0
Instance details Defined in Data.Semigroup.Internal Methods (+) :: Product a -> Product a -> Product a # (-) :: Product a -> Product a -> Product a # (*) :: Product a -> Product a -> Product a # negate :: Product a -> Product a # abs :: Product a -> Product a # signum :: Product a -> Product a # fromInteger :: Integer -> Product a #
Ord a => Ord (Product a)	Since: base-2.1
Instance details Defined in Data.Semigroup.Internal Methods compare :: Product a -> Product a -> Ordering # (<) :: Product a -> Product a -> Bool # (<=) :: Product a -> Product a -> Bool # (>) :: Product a -> Product a -> Bool # (>=) :: Product a -> Product a -> Bool # max :: Product a -> Product a -> Product a # min :: Product a -> Product a -> Product a #
Read a => Read (Product a)	Since: base-2.1
Instance details Defined in Data.Semigroup.Internal Methods readsPrec :: Int -> ReadS (Product a) # readList :: ReadS [Product a] # readPrec :: ReadPrec (Product a) # readListPrec :: ReadPrec [Product a] #
Show a => Show (Product a)	Since: base-2.1
Instance details Defined in Data.Semigroup.Internal Methods showsPrec :: Int -> Product a -> ShowS # show :: Product a -> String # showList :: [Product a] -> ShowS #
Generic (Product a)
Instance details Defined in Data.Semigroup.Internal Associated Types type Rep (Product a) :: Type -> Type # Methods from :: Product a -> Rep (Product a) x # to :: Rep (Product a) x -> Product a #
Num a => Semigroup (Product a)	Since: base-4.9.0.0
Instance details Defined in Data.Semigroup.Internal Methods (<>) :: Product a -> Product a -> Product a # sconcat :: NonEmpty (Product a) -> Product a # stimes :: Integral b => b -> Product a -> Product a #
Num a => Monoid (Product a)	Since: base-2.1
Instance details Defined in Data.Semigroup.Internal Methods mempty :: Product a # mappend :: Product a -> Product a -> Product a # mconcat :: [Product a] -> Product a #
NFData a => NFData (Product a)	Since: deepseq-1.4.0.0
Instance details Defined in Control.DeepSeq Methods rnf :: Product a -> () #
Container (Product a)
Instance details Defined in Universum.Container.Class Associated Types type Element (Product a) :: Type # Methods toList :: Product a -> [Element (Product a)] # null :: Product a -> Bool # foldr :: (Element (Product a) -> b -> b) -> b -> Product a -> b # foldl :: (b -> Element (Product a) -> b) -> b -> Product a -> b # foldl' :: (b -> Element (Product a) -> b) -> b -> Product a -> b # length :: Product a -> Int # elem :: Element (Product a) -> Product a -> Bool # maximum :: Product a -> Element (Product a) # minimum :: Product a -> Element (Product a) # foldMap :: Monoid m => (Element (Product a) -> m) -> Product a -> m # fold :: Product a -> Element (Product a) # foldr' :: (Element (Product a) -> b -> b) -> b -> Product a -> b # foldr1 :: (Element (Product a) -> Element (Product a) -> Element (Product a)) -> Product a -> Element (Product a) # foldl1 :: (Element (Product a) -> Element (Product a) -> Element (Product a)) -> Product a -> Element (Product a) # notElem :: Element (Product a) -> Product a -> Bool # all :: (Element (Product a) -> Bool) -> Product a -> Bool # any :: (Element (Product a) -> Bool) -> Product a -> Bool # and :: Product a -> Bool # or :: Product a -> Bool # find :: (Element (Product a) -> Bool) -> Product a -> Maybe (Element (Product a)) # safeHead :: Product a -> Maybe (Element (Product a)) #
Generic1 Product
Instance details Defined in Data.Semigroup.Internal Associated Types type Rep1 Product :: k -> Type # Methods from1 :: Product a -> Rep1 Product a # to1 :: Rep1 Product a -> Product a #
type Rep (Product a)	Since: base-4.7.0.0
Instance details Defined in Data.Semigroup.Internal type Rep (Product a) = D1 (MetaData "Product" "Data.Semigroup.Internal" "base" True) (C1 (MetaCons "Product" PrefixI True) (S1 (MetaSel (Just "getProduct") NoSourceUnpackedness NoSourceStrictness DecidedLazy) (Rec0 a)))
type Element (Product a)
Instance details Defined in Universum.Container.Class type Element (Product a) = ElementDefault (Product a)
type Rep1 Product	Since: base-4.7.0.0
Instance details Defined in Data.Semigroup.Internal type Rep1 Product = D1 (MetaData "Product" "Data.Semigroup.Internal" "base" True) (C1 (MetaCons "Product" PrefixI True) (S1 (MetaSel (Just "getProduct") NoSourceUnpackedness NoSourceStrictness DecidedLazy) Par1))

newtype Alt (f :: k -> Type) (a :: k) :: forall k. (k -> Type) -> k -> Type #

Monoid under <|>.

Since: base-4.8.0.0

Constructors

Alt
Fields getAlt :: f a

Instances

Generic1 (Alt f :: k -> Type)
Instance details Defined in Data.Semigroup.Internal Associated Types type Rep1 (Alt f) :: k -> Type # Methods from1 :: Alt f a -> Rep1 (Alt f) a # to1 :: Rep1 (Alt f) a -> Alt f a #
Monad f => Monad (Alt f)	Since: base-4.8.0.0
Instance details Defined in Data.Semigroup.Internal Methods (>>=) :: Alt f a -> (a -> Alt f b) -> Alt f b # (>>) :: Alt f a -> Alt f b -> Alt f b # return :: a -> Alt f a # fail :: String -> Alt f a #
Functor f => Functor (Alt f)	Since: base-4.8.0.0
Instance details Defined in Data.Semigroup.Internal Methods fmap :: (a -> b) -> Alt f a -> Alt f b # (<$) :: a -> Alt f b -> Alt f a #
Applicative f => Applicative (Alt f)	Since: base-4.8.0.0
Instance details Defined in Data.Semigroup.Internal Methods pure :: a -> Alt f a # (<>) :: Alt f (a -> b) -> Alt f a -> Alt f b # liftA2 :: (a -> b -> c) -> Alt f a -> Alt f b -> Alt f c # (>) :: Alt f a -> Alt f b -> Alt f b # (<*) :: Alt f a -> Alt f b -> Alt f a #
Foldable f => Foldable (Alt f)	Since: base-4.12.0.0
Instance details Defined in Data.Foldable Methods fold :: Monoid m => Alt f m -> m # foldMap :: Monoid m => (a -> m) -> Alt f a -> m # foldr :: (a -> b -> b) -> b -> Alt f a -> b # foldr' :: (a -> b -> b) -> b -> Alt f a -> b # foldl :: (b -> a -> b) -> b -> Alt f a -> b # foldl' :: (b -> a -> b) -> b -> Alt f a -> b # foldr1 :: (a -> a -> a) -> Alt f a -> a # foldl1 :: (a -> a -> a) -> Alt f a -> a # toList :: Alt f a -> [a] # null :: Alt f a -> Bool # length :: Alt f a -> Int # elem :: Eq a => a -> Alt f a -> Bool # maximum :: Ord a => Alt f a -> a # minimum :: Ord a => Alt f a -> a # sum :: Num a => Alt f a -> a # product :: Num a => Alt f a -> a #
Traversable f => Traversable (Alt f)	Since: base-4.12.0.0
Instance details Defined in Data.Traversable Methods traverse :: Applicative f0 => (a -> f0 b) -> Alt f a -> f0 (Alt f b) # sequenceA :: Applicative f0 => Alt f (f0 a) -> f0 (Alt f a) # mapM :: Monad m => (a -> m b) -> Alt f a -> m (Alt f b) # sequence :: Monad m => Alt f (m a) -> m (Alt f a) #
Alternative f => Alternative (Alt f)	Since: base-4.8.0.0
Instance details Defined in Data.Semigroup.Internal Methods empty :: Alt f a # (<\|>) :: Alt f a -> Alt f a -> Alt f a # some :: Alt f a -> Alt f [a] # many :: Alt f a -> Alt f [a] #
MonadPlus f => MonadPlus (Alt f)	Since: base-4.8.0.0
Instance details Defined in Data.Semigroup.Internal Methods mzero :: Alt f a # mplus :: Alt f a -> Alt f a -> Alt f a #
Enum (f a) => Enum (Alt f a)	Since: base-4.8.0.0
Instance details Defined in Data.Semigroup.Internal Methods succ :: Alt f a -> Alt f a # pred :: Alt f a -> Alt f a # toEnum :: Int -> Alt f a # fromEnum :: Alt f a -> Int # enumFrom :: Alt f a -> [Alt f a] # enumFromThen :: Alt f a -> Alt f a -> [Alt f a] # enumFromTo :: Alt f a -> Alt f a -> [Alt f a] # enumFromThenTo :: Alt f a -> Alt f a -> Alt f a -> [Alt f a] #
Eq (f a) => Eq (Alt f a)	Since: base-4.8.0.0
Instance details Defined in Data.Semigroup.Internal Methods (==) :: Alt f a -> Alt f a -> Bool # (/=) :: Alt f a -> Alt f a -> Bool #
Num (f a) => Num (Alt f a)	Since: base-4.8.0.0
Instance details Defined in Data.Semigroup.Internal Methods (+) :: Alt f a -> Alt f a -> Alt f a # (-) :: Alt f a -> Alt f a -> Alt f a # (*) :: Alt f a -> Alt f a -> Alt f a # negate :: Alt f a -> Alt f a # abs :: Alt f a -> Alt f a # signum :: Alt f a -> Alt f a # fromInteger :: Integer -> Alt f a #
Ord (f a) => Ord (Alt f a)	Since: base-4.8.0.0
Instance details Defined in Data.Semigroup.Internal Methods compare :: Alt f a -> Alt f a -> Ordering # (<) :: Alt f a -> Alt f a -> Bool # (<=) :: Alt f a -> Alt f a -> Bool # (>) :: Alt f a -> Alt f a -> Bool # (>=) :: Alt f a -> Alt f a -> Bool # max :: Alt f a -> Alt f a -> Alt f a # min :: Alt f a -> Alt f a -> Alt f a #
Read (f a) => Read (Alt f a)	Since: base-4.8.0.0
Instance details Defined in Data.Semigroup.Internal Methods readsPrec :: Int -> ReadS (Alt f a) # readList :: ReadS [Alt f a] # readPrec :: ReadPrec (Alt f a) # readListPrec :: ReadPrec [Alt f a] #
Show (f a) => Show (Alt f a)	Since: base-4.8.0.0
Instance details Defined in Data.Semigroup.Internal Methods showsPrec :: Int -> Alt f a -> ShowS # show :: Alt f a -> String # showList :: [Alt f a] -> ShowS #
Generic (Alt f a)
Instance details Defined in Data.Semigroup.Internal Associated Types type Rep (Alt f a) :: Type -> Type # Methods from :: Alt f a -> Rep (Alt f a) x # to :: Rep (Alt f a) x -> Alt f a #
Alternative f => Semigroup (Alt f a)	Since: base-4.9.0.0
Instance details Defined in Data.Semigroup.Internal Methods (<>) :: Alt f a -> Alt f a -> Alt f a # sconcat :: NonEmpty (Alt f a) -> Alt f a # stimes :: Integral b => b -> Alt f a -> Alt f a #
Alternative f => Monoid (Alt f a)	Since: base-4.8.0.0
Instance details Defined in Data.Semigroup.Internal Methods mempty :: Alt f a # mappend :: Alt f a -> Alt f a -> Alt f a # mconcat :: [Alt f a] -> Alt f a #
type Rep1 (Alt f :: k -> Type)	Since: base-4.8.0.0
Instance details Defined in Data.Semigroup.Internal type Rep1 (Alt f :: k -> Type) = D1 (MetaData "Alt" "Data.Semigroup.Internal" "base" True) (C1 (MetaCons "Alt" PrefixI True) (S1 (MetaSel (Just "getAlt") NoSourceUnpackedness NoSourceStrictness DecidedLazy) (Rec1 f)))
type Rep (Alt f a)	Since: base-4.8.0.0
Instance details Defined in Data.Semigroup.Internal type Rep (Alt f a) = D1 (MetaData "Alt" "Data.Semigroup.Internal" "base" True) (C1 (MetaCons "Alt" PrefixI True) (S1 (MetaSel (Just "getAlt") NoSourceUnpackedness NoSourceStrictness DecidedLazy) (Rec0 (f a))))

someNatVal :: Natural -> SomeNat #

Convert an integer into an unknown type-level natural.

Since: base-4.10.0.0

natVal :: KnownNat n => proxy n -> Natural #

Since: base-4.10.0.0

data SomeNat where #

This type represents unknown type-level natural numbers.

Since: base-4.10.0.0

Constructors

SomeNat :: forall (n :: Nat). KnownNat n => Proxy n -> SomeNat

Instances

Eq SomeNat	Since: base-4.7.0.0
Instance details Defined in GHC.TypeNats Methods (==) :: SomeNat -> SomeNat -> Bool # (/=) :: SomeNat -> SomeNat -> Bool #
Ord SomeNat	Since: base-4.7.0.0
Instance details Defined in GHC.TypeNats Methods compare :: SomeNat -> SomeNat -> Ordering # (<) :: SomeNat -> SomeNat -> Bool # (<=) :: SomeNat -> SomeNat -> Bool # (>) :: SomeNat -> SomeNat -> Bool # (>=) :: SomeNat -> SomeNat -> Bool # max :: SomeNat -> SomeNat -> SomeNat # min :: SomeNat -> SomeNat -> SomeNat #
Read SomeNat	Since: base-4.7.0.0
Instance details Defined in GHC.TypeNats Methods readsPrec :: Int -> ReadS SomeNat # readList :: ReadS [SomeNat] # readPrec :: ReadPrec SomeNat # readListPrec :: ReadPrec [SomeNat] #
Show SomeNat	Since: base-4.7.0.0
Instance details Defined in GHC.TypeNats Methods showsPrec :: Int -> SomeNat -> ShowS # show :: SomeNat -> String # showList :: [SomeNat] -> ShowS #

unfoldr :: (b -> Maybe (a, b)) -> b -> [a] #

The unfoldr function is a `dual' to foldr: while foldr reduces a list to a summary value, unfoldr builds a list from a seed value. The function takes the element and returns Nothing if it is done producing the list or returns Just (a,b), in which case, a is a prepended to the list and b is used as the next element in a recursive call. For example,

iterate f == unfoldr (\x -> Just (x, f x))

In some cases, unfoldr can undo a foldr operation:

unfoldr f' (foldr f z xs) == xs

if the following holds:

f' (f x y) = Just (x,y)
f' z       = Nothing

A simple use of unfoldr:

>>> unfoldr (\b -> if b == 0 then Nothing else Just (b, b-1)) 10
[10,9,8,7,6,5,4,3,2,1]

sortOn :: Ord b => (a -> b) -> [a] -> [a] #

Sort a list by comparing the results of a key function applied to each element. sortOn f is equivalent to sortBy (comparing f), but has the performance advantage of only evaluating f once for each element in the input list. This is called the decorate-sort-undecorate paradigm, or Schwartzian transform.

Elements are arranged from from lowest to highest, keeping duplicates in the order they appeared in the input.

>>> sortOn fst [(2, "world"), (4, "!"), (1, "Hello")]
[(1,"Hello"),(2,"world"),(4,"!")]

Since: base-4.8.0.0

sortBy :: (a -> a -> Ordering) -> [a] -> [a] #

The sortBy function is the non-overloaded version of sort.

>>> sortBy (\(a,_) (b,_) -> compare a b) [(2, "world"), (4, "!"), (1, "Hello")]
[(1,"Hello"),(2,"world"),(4,"!")]

sort :: Ord a => [a] -> [a] #

The sort function implements a stable sorting algorithm. It is a special case of sortBy, which allows the programmer to supply their own comparison function.

Elements are arranged from from lowest to highest, keeping duplicates in the order they appeared in the input.

>>> sort [1,6,4,3,2,5]
[1,2,3,4,5,6]

permutations :: [a] -> [[a]] #

The permutations function returns the list of all permutations of the argument.

>>> permutations "abc"
["abc","bac","cba","bca","cab","acb"]

subsequences :: [a] -> [[a]] #

The subsequences function returns the list of all subsequences of the argument.

>>> subsequences "abc"
["","a","b","ab","c","ac","bc","abc"]

tails :: [a] -> [[a]] #

The tails function returns all final segments of the argument, longest first. For example,

>>> tails "abc"
["abc","bc","c",""]

Note that tails has the following strictness property: tails _|_ = _|_ : _|_

inits :: [a] -> [[a]] #

The inits function returns all initial segments of the argument, shortest first. For example,

>>> inits "abc"
["","a","ab","abc"]

Note that inits has the following strictness property: inits (xs ++ _|_) = inits xs ++ _|_

In particular, inits _|_ = [] : _|_

group :: Eq a => [a] -> [[a]] #

The group function takes a list and returns a list of lists such that the concatenation of the result is equal to the argument. Moreover, each sublist in the result contains only equal elements. For example,

>>> group "Mississippi"
["M","i","ss","i","ss","i","pp","i"]

It is a special case of groupBy, which allows the programmer to supply their own equality test.

genericReplicate :: Integral i => i -> a -> [a] #

The genericReplicate function is an overloaded version of replicate, which accepts any Integral value as the number of repetitions to make.

genericSplitAt :: Integral i => i -> [a] -> ([a], [a]) #

The genericSplitAt function is an overloaded version of splitAt, which accepts any Integral value as the position at which to split.

genericDrop :: Integral i => i -> [a] -> [a] #

The genericDrop function is an overloaded version of drop, which accepts any Integral value as the number of elements to drop.

genericTake :: Integral i => i -> [a] -> [a] #

The genericTake function is an overloaded version of take, which accepts any Integral value as the number of elements to take.

genericLength :: Num i => [a] -> i #

The genericLength function is an overloaded version of length. In particular, instead of returning an Int, it returns any type which is an instance of Num. It is, however, less efficient than length.

transpose :: [[a]] -> [[a]] #

The transpose function transposes the rows and columns of its argument. For example,

>>> transpose [[1,2,3],[4,5,6]]
[[1,4],[2,5],[3,6]]

If some of the rows are shorter than the following rows, their elements are skipped:

>>> transpose [[10,11],[20],[],[30,31,32]]
[[10,20,30],[11,31],[32]]

intercalate :: [a] -> [[a]] -> [a] #

intercalate xs xss is equivalent to (concat (intersperse xs xss)). It inserts the list xs in between the lists in xss and concatenates the result.

>>> intercalate ", " ["Lorem", "ipsum", "dolor"]
"Lorem, ipsum, dolor"

intersperse :: a -> [a] -> [a] #

The intersperse function takes an element and a list and `intersperses' that element between the elements of the list. For example,

>>> intersperse ',' "abcde"
"a,b,c,d,e"

isPrefixOf :: Eq a => [a] -> [a] -> Bool #

The isPrefixOf function takes two lists and returns True iff the first list is a prefix of the second.

>>> "Hello" `isPrefixOf` "Hello World!"
True

>>> "Hello" `isPrefixOf` "Wello Horld!"
False

readMaybe :: Read a => String -> Maybe a #

Parse a string using the Read instance. Succeeds if there is exactly one valid result.

>>> readMaybe "123" :: Maybe Int
Just 123

>>> readMaybe "hello" :: Maybe Int
Nothing

Since: base-4.6.0.0

reads :: Read a => ReadS a #

equivalent to readsPrec with a precedence of 0.

isRight :: Either a b -> Bool #

Return True if the given value is a Right-value, False otherwise.

Examples

Expand

Basic usage:

>>> isRight (Left "foo")
False
>>> isRight (Right 3)
True

Assuming a Left value signifies some sort of error, we can use isRight to write a very simple reporting function that only outputs "SUCCESS" when a computation has succeeded.

This example shows how isRight might be used to avoid pattern matching when one does not care about the value contained in the constructor:

>>> import Control.Monad ( when )
>>> let report e = when (isRight e) $ putStrLn "SUCCESS"
>>> report (Left "parse error")
>>> report (Right 1)
SUCCESS

Since: base-4.7.0.0

isLeft :: Either a b -> Bool #

Return True if the given value is a Left-value, False otherwise.

Examples

Expand

Basic usage:

>>> isLeft (Left "foo")
True
>>> isLeft (Right 3)
False

Assuming a Left value signifies some sort of error, we can use isLeft to write a very simple error-reporting function that does absolutely nothing in the case of success, and outputs "ERROR" if any error occurred.

This example shows how isLeft might be used to avoid pattern matching when one does not care about the value contained in the constructor:

>>> import Control.Monad ( when )
>>> let report e = when (isLeft e) $ putStrLn "ERROR"
>>> report (Right 1)
>>> report (Left "parse error")
ERROR

Since: base-4.7.0.0

partitionEithers :: [Either a b] -> ([a], [b]) #

Partitions a list of Either into two lists. All the Left elements are extracted, in order, to the first component of the output. Similarly the Right elements are extracted to the second component of the output.

Examples

Expand

Basic usage:

>>> let list = [ Left "foo", Right 3, Left "bar", Right 7, Left "baz" ]
>>> partitionEithers list
(["foo","bar","baz"],[3,7])

The pair returned by partitionEithers x should be the same pair as (lefts x, rights x):

>>> let list = [ Left "foo", Right 3, Left "bar", Right 7, Left "baz" ]
>>> partitionEithers list == (lefts list, rights list)
True

rights :: [Either a b] -> [b] #

Extracts from a list of Either all the Right elements. All the Right elements are extracted in order.

Examples

Expand

Basic usage:

>>> let list = [ Left "foo", Right 3, Left "bar", Right 7, Left "baz" ]
>>> rights list
[3,7]

lefts :: [Either a b] -> [a] #

Extracts from a list of Either all the Left elements. All the Left elements are extracted in order.

Examples

Expand

Basic usage:

>>> let list = [ Left "foo", Right 3, Left "bar", Right 7, Left "baz" ]
>>> lefts list
["foo","bar","baz"]

either :: (a -> c) -> (b -> c) -> Either a b -> c #

Case analysis for the Either type. If the value is Left a, apply the first function to a; if it is Right b, apply the second function to b.

Examples

Expand

We create two values of type Either String Int, one using the Left constructor and another using the Right constructor. Then we apply "either" the length function (if we have a String) or the "times-two" function (if we have an Int):

>>> let s = Left "foo" :: Either String Int
>>> let n = Right 3 :: Either String Int
>>> either length (*2) s
3
>>> either length (*2) n
6

comparing :: Ord a => (b -> a) -> b -> b -> Ordering #

comparing p x y = compare (p x) (p y)

Useful combinator for use in conjunction with the xxxBy family of functions from Data.List, for example:

  ... sortBy (comparing fst) ...

newtype Down a #

The Down type allows you to reverse sort order conveniently. A value of type Down a contains a value of type a (represented as Down a). If a has an Ord instance associated with it then comparing two values thus wrapped will give you the opposite of their normal sort order. This is particularly useful when sorting in generalised list comprehensions, as in: then sortWith by Down x

Since: base-4.6.0.0

Constructors

Down a

Instances

Monad Down	Since: base-4.11.0.0
Instance details Defined in Data.Ord Methods (>>=) :: Down a -> (a -> Down b) -> Down b # (>>) :: Down a -> Down b -> Down b # return :: a -> Down a # fail :: String -> Down a #
Functor Down	Since: base-4.11.0.0
Instance details Defined in Data.Ord Methods fmap :: (a -> b) -> Down a -> Down b # (<$) :: a -> Down b -> Down a #
Applicative Down	Since: base-4.11.0.0
Instance details Defined in Data.Ord Methods pure :: a -> Down a # (<>) :: Down (a -> b) -> Down a -> Down b # liftA2 :: (a -> b -> c) -> Down a -> Down b -> Down c # (>) :: Down a -> Down b -> Down b # (<*) :: Down a -> Down b -> Down a #
Foldable Down	Since: base-4.12.0.0
Instance details Defined in Data.Foldable Methods fold :: Monoid m => Down m -> m # foldMap :: Monoid m => (a -> m) -> Down a -> m # foldr :: (a -> b -> b) -> b -> Down a -> b # foldr' :: (a -> b -> b) -> b -> Down a -> b # foldl :: (b -> a -> b) -> b -> Down a -> b # foldl' :: (b -> a -> b) -> b -> Down a -> b # foldr1 :: (a -> a -> a) -> Down a -> a # foldl1 :: (a -> a -> a) -> Down a -> a # toList :: Down a -> [a] # null :: Down a -> Bool # length :: Down a -> Int # elem :: Eq a => a -> Down a -> Bool # maximum :: Ord a => Down a -> a # minimum :: Ord a => Down a -> a # sum :: Num a => Down a -> a # product :: Num a => Down a -> a #
Traversable Down	Since: base-4.12.0.0
Instance details Defined in Data.Traversable Methods traverse :: Applicative f => (a -> f b) -> Down a -> f (Down b) # sequenceA :: Applicative f => Down (f a) -> f (Down a) # mapM :: Monad m => (a -> m b) -> Down a -> m (Down b) # sequence :: Monad m => Down (m a) -> m (Down a) #
NFData1 Down	Since: deepseq-1.4.3.0
Instance details Defined in Control.DeepSeq Methods liftRnf :: (a -> ()) -> Down a -> () #
Eq a => Eq (Down a)	Since: base-4.6.0.0
Instance details Defined in Data.Ord Methods (==) :: Down a -> Down a -> Bool # (/=) :: Down a -> Down a -> Bool #
Num a => Num (Down a)	Since: base-4.11.0.0
Instance details Defined in Data.Ord Methods (+) :: Down a -> Down a -> Down a # (-) :: Down a -> Down a -> Down a # (*) :: Down a -> Down a -> Down a # negate :: Down a -> Down a # abs :: Down a -> Down a # signum :: Down a -> Down a # fromInteger :: Integer -> Down a #
Ord a => Ord (Down a)	Since: base-4.6.0.0
Instance details Defined in Data.Ord Methods compare :: Down a -> Down a -> Ordering # (<) :: Down a -> Down a -> Bool # (<=) :: Down a -> Down a -> Bool # (>) :: Down a -> Down a -> Bool # (>=) :: Down a -> Down a -> Bool # max :: Down a -> Down a -> Down a # min :: Down a -> Down a -> Down a #
Read a => Read (Down a)	Since: base-4.7.0.0
Instance details Defined in Data.Ord Methods readsPrec :: Int -> ReadS (Down a) # readList :: ReadS [Down a] # readPrec :: ReadPrec (Down a) # readListPrec :: ReadPrec [Down a] #
Show a => Show (Down a)	Since: base-4.7.0.0
Instance details Defined in Data.Ord Methods showsPrec :: Int -> Down a -> ShowS # show :: Down a -> String # showList :: [Down a] -> ShowS #
Generic (Down a)
Instance details Defined in GHC.Generics Associated Types type Rep (Down a) :: Type -> Type # Methods from :: Down a -> Rep (Down a) x # to :: Rep (Down a) x -> Down a #
Semigroup a => Semigroup (Down a)	Since: base-4.11.0.0
Instance details Defined in Data.Ord Methods (<>) :: Down a -> Down a -> Down a # sconcat :: NonEmpty (Down a) -> Down a # stimes :: Integral b => b -> Down a -> Down a #
Monoid a => Monoid (Down a)	Since: base-4.11.0.0
Instance details Defined in Data.Ord Methods mempty :: Down a # mappend :: Down a -> Down a -> Down a # mconcat :: [Down a] -> Down a #
NFData a => NFData (Down a)	Since: deepseq-1.4.0.0
Instance details Defined in Control.DeepSeq Methods rnf :: Down a -> () #
Generic1 Down
Instance details Defined in GHC.Generics Associated Types type Rep1 Down :: k -> Type # Methods from1 :: Down a -> Rep1 Down a # to1 :: Rep1 Down a -> Down a #
type Rep (Down a)	Since: base-4.12.0.0
Instance details Defined in GHC.Generics type Rep (Down a) = D1 (MetaData "Down" "Data.Ord" "base" True) (C1 (MetaCons "Down" PrefixI False) (S1 (MetaSel (Nothing :: Maybe Symbol) NoSourceUnpackedness NoSourceStrictness DecidedLazy) (Rec0 a)))
type Rep1 Down	Since: base-4.12.0.0
Instance details Defined in GHC.Generics type Rep1 Down = D1 (MetaData "Down" "Data.Ord" "base" True) (C1 (MetaCons "Down" PrefixI False) (S1 (MetaSel (Nothing :: Maybe Symbol) NoSourceUnpackedness NoSourceStrictness DecidedLazy) Par1))

data Proxy (t :: k) :: forall k. k -> Type #

Proxy is a type that holds no data, but has a phantom parameter of arbitrary type (or even kind). Its use is to provide type information, even though there is no value available of that type (or it may be too costly to create one).

Historically, Proxy :: Proxy a is a safer alternative to the 'undefined :: a' idiom.

>>> Proxy :: Proxy (Void, Int -> Int)
Proxy

Proxy can even hold types of higher kinds,

>>> Proxy :: Proxy Either
Proxy

>>> Proxy :: Proxy Functor
Proxy

>>> Proxy :: Proxy complicatedStructure
Proxy

Constructors

Proxy

Instances

Generic1 (Proxy :: k -> Type)
Instance details Defined in GHC.Generics Associated Types type Rep1 Proxy :: k -> Type # Methods from1 :: Proxy a -> Rep1 Proxy a # to1 :: Rep1 Proxy a -> Proxy a #
Monad (Proxy :: Type -> Type)	Since: base-4.7.0.0
Instance details Defined in Data.Proxy Methods (>>=) :: Proxy a -> (a -> Proxy b) -> Proxy b # (>>) :: Proxy a -> Proxy b -> Proxy b # return :: a -> Proxy a # fail :: String -> Proxy a #
Functor (Proxy :: Type -> Type)	Since: base-4.7.0.0
Instance details Defined in Data.Proxy Methods fmap :: (a -> b) -> Proxy a -> Proxy b # (<$) :: a -> Proxy b -> Proxy a #
Applicative (Proxy :: Type -> Type)	Since: base-4.7.0.0
Instance details Defined in Data.Proxy Methods pure :: a -> Proxy a # (<>) :: Proxy (a -> b) -> Proxy a -> Proxy b # liftA2 :: (a -> b -> c) -> Proxy a -> Proxy b -> Proxy c # (>) :: Proxy a -> Proxy b -> Proxy b # (<*) :: Proxy a -> Proxy b -> Proxy a #
Foldable (Proxy :: Type -> Type)	Since: base-4.7.0.0
Instance details Defined in Data.Foldable Methods fold :: Monoid m => Proxy m -> m # foldMap :: Monoid m => (a -> m) -> Proxy a -> m # foldr :: (a -> b -> b) -> b -> Proxy a -> b # foldr' :: (a -> b -> b) -> b -> Proxy a -> b # foldl :: (b -> a -> b) -> b -> Proxy a -> b # foldl' :: (b -> a -> b) -> b -> Proxy a -> b # foldr1 :: (a -> a -> a) -> Proxy a -> a # foldl1 :: (a -> a -> a) -> Proxy a -> a # toList :: Proxy a -> [a] # null :: Proxy a -> Bool # length :: Proxy a -> Int # elem :: Eq a => a -> Proxy a -> Bool # maximum :: Ord a => Proxy a -> a # minimum :: Ord a => Proxy a -> a # sum :: Num a => Proxy a -> a # product :: Num a => Proxy a -> a #
Traversable (Proxy :: Type -> Type)	Since: base-4.7.0.0
Instance details Defined in Data.Traversable Methods traverse :: Applicative f => (a -> f b) -> Proxy a -> f (Proxy b) # sequenceA :: Applicative f => Proxy (f a) -> f (Proxy a) # mapM :: Monad m => (a -> m b) -> Proxy a -> m (Proxy b) # sequence :: Monad m => Proxy (m a) -> m (Proxy a) #
Alternative (Proxy :: Type -> Type)	Since: base-4.9.0.0
Instance details Defined in Data.Proxy Methods empty :: Proxy a # (<\|>) :: Proxy a -> Proxy a -> Proxy a # some :: Proxy a -> Proxy [a] # many :: Proxy a -> Proxy [a] #
MonadPlus (Proxy :: Type -> Type)	Since: base-4.9.0.0
Instance details Defined in Data.Proxy Methods mzero :: Proxy a # mplus :: Proxy a -> Proxy a -> Proxy a #
NFData1 (Proxy :: Type -> Type)	Since: deepseq-1.4.3.0
Instance details Defined in Control.DeepSeq Methods liftRnf :: (a -> ()) -> Proxy a -> () #
Hashable1 (Proxy :: Type -> Type)
Instance details Defined in Data.Hashable.Class Methods liftHashWithSalt :: (Int -> a -> Int) -> Int -> Proxy a -> Int #
Bounded (Proxy t)	Since: base-4.7.0.0
Instance details Defined in Data.Proxy Methods minBound :: Proxy t # maxBound :: Proxy t #
Enum (Proxy s)	Since: base-4.7.0.0
Instance details Defined in Data.Proxy Methods succ :: Proxy s -> Proxy s # pred :: Proxy s -> Proxy s # toEnum :: Int -> Proxy s # fromEnum :: Proxy s -> Int # enumFrom :: Proxy s -> [Proxy s] # enumFromThen :: Proxy s -> Proxy s -> [Proxy s] # enumFromTo :: Proxy s -> Proxy s -> [Proxy s] # enumFromThenTo :: Proxy s -> Proxy s -> Proxy s -> [Proxy s] #
Eq (Proxy s)	Since: base-4.7.0.0
Instance details Defined in Data.Proxy Methods (==) :: Proxy s -> Proxy s -> Bool # (/=) :: Proxy s -> Proxy s -> Bool #
Ord (Proxy s)	Since: base-4.7.0.0
Instance details Defined in Data.Proxy Methods compare :: Proxy s -> Proxy s -> Ordering # (<) :: Proxy s -> Proxy s -> Bool # (<=) :: Proxy s -> Proxy s -> Bool # (>) :: Proxy s -> Proxy s -> Bool # (>=) :: Proxy s -> Proxy s -> Bool # max :: Proxy s -> Proxy s -> Proxy s # min :: Proxy s -> Proxy s -> Proxy s #
Read (Proxy t)	Since: base-4.7.0.0
Instance details Defined in Data.Proxy Methods readsPrec :: Int -> ReadS (Proxy t) # readList :: ReadS [Proxy t] # readPrec :: ReadPrec (Proxy t) # readListPrec :: ReadPrec [Proxy t] #
Show (Proxy s)	Since: base-4.7.0.0
Instance details Defined in Data.Proxy Methods showsPrec :: Int -> Proxy s -> ShowS # show :: Proxy s -> String # showList :: [Proxy s] -> ShowS #
Ix (Proxy s)	Since: base-4.7.0.0
Instance details Defined in Data.Proxy Methods range :: (Proxy s, Proxy s) -> [Proxy s] # index :: (Proxy s, Proxy s) -> Proxy s -> Int # unsafeIndex :: (Proxy s, Proxy s) -> Proxy s -> Int inRange :: (Proxy s, Proxy s) -> Proxy s -> Bool # rangeSize :: (Proxy s, Proxy s) -> Int # unsafeRangeSize :: (Proxy s, Proxy s) -> Int
Generic (Proxy t)
Instance details Defined in GHC.Generics Associated Types type Rep (Proxy t) :: Type -> Type # Methods from :: Proxy t -> Rep (Proxy t) x # to :: Rep (Proxy t) x -> Proxy t #
Semigroup (Proxy s)	Since: base-4.9.0.0
Instance details Defined in Data.Proxy Methods (<>) :: Proxy s -> Proxy s -> Proxy s # sconcat :: NonEmpty (Proxy s) -> Proxy s # stimes :: Integral b => b -> Proxy s -> Proxy s #
Monoid (Proxy s)	Since: base-4.7.0.0
Instance details Defined in Data.Proxy Methods mempty :: Proxy s # mappend :: Proxy s -> Proxy s -> Proxy s # mconcat :: [Proxy s] -> Proxy s #
NFData (Proxy a)	Since: deepseq-1.4.0.0
Instance details Defined in Control.DeepSeq Methods rnf :: Proxy a -> () #
Hashable (Proxy a)
Instance details Defined in Data.Hashable.Class Methods hashWithSalt :: Int -> Proxy a -> Int # hash :: Proxy a -> Int #
type Rep1 (Proxy :: k -> Type)	Since: base-4.6.0.0
Instance details Defined in GHC.Generics type Rep1 (Proxy :: k -> Type) = D1 (MetaData "Proxy" "Data.Proxy" "base" False) (C1 (MetaCons "Proxy" PrefixI False) (U1 :: k -> Type))
type Rep (Proxy t)	Since: base-4.6.0.0
Instance details Defined in GHC.Generics type Rep (Proxy t) = D1 (MetaData "Proxy" "Data.Proxy" "base" False) (C1 (MetaCons "Proxy" PrefixI False) (U1 :: Type -> Type))

data IOMode #

See openFile

Constructors

ReadMode
WriteMode
AppendMode
ReadWriteMode

Instances

Enum IOMode	Since: base-4.2.0.0
Instance details Defined in GHC.IO.IOMode Methods succ :: IOMode -> IOMode # pred :: IOMode -> IOMode # toEnum :: Int -> IOMode # fromEnum :: IOMode -> Int # enumFrom :: IOMode -> [IOMode] # enumFromThen :: IOMode -> IOMode -> [IOMode] # enumFromTo :: IOMode -> IOMode -> [IOMode] # enumFromThenTo :: IOMode -> IOMode -> IOMode -> [IOMode] #
Eq IOMode	Since: base-4.2.0.0
Instance details Defined in GHC.IO.IOMode Methods (==) :: IOMode -> IOMode -> Bool # (/=) :: IOMode -> IOMode -> Bool #
Ord IOMode	Since: base-4.2.0.0
Instance details Defined in GHC.IO.IOMode Methods compare :: IOMode -> IOMode -> Ordering # (<) :: IOMode -> IOMode -> Bool # (<=) :: IOMode -> IOMode -> Bool # (>) :: IOMode -> IOMode -> Bool # (>=) :: IOMode -> IOMode -> Bool # max :: IOMode -> IOMode -> IOMode # min :: IOMode -> IOMode -> IOMode #
Read IOMode	Since: base-4.2.0.0
Instance details Defined in GHC.IO.IOMode Methods readsPrec :: Int -> ReadS IOMode # readList :: ReadS [IOMode] # readPrec :: ReadPrec IOMode # readListPrec :: ReadPrec [IOMode] #
Show IOMode	Since: base-4.2.0.0
Instance details Defined in GHC.IO.IOMode Methods showsPrec :: Int -> IOMode -> ShowS # show :: IOMode -> String # showList :: [IOMode] -> ShowS #
Ix IOMode	Since: base-4.2.0.0
Instance details Defined in GHC.IO.IOMode Methods range :: (IOMode, IOMode) -> [IOMode] # index :: (IOMode, IOMode) -> IOMode -> Int # unsafeIndex :: (IOMode, IOMode) -> IOMode -> Int inRange :: (IOMode, IOMode) -> IOMode -> Bool # rangeSize :: (IOMode, IOMode) -> Int # unsafeRangeSize :: (IOMode, IOMode) -> Int

byteSwap64 :: Word64 -> Word64 #

Reverse order of bytes in Word64.

Since: base-4.7.0.0

byteSwap32 :: Word32 -> Word32 #

Reverse order of bytes in Word32.

Since: base-4.7.0.0

byteSwap16 :: Word16 -> Word16 #

Swap bytes in Word16.

Since: base-4.7.0.0

xor :: Bits a => a -> a -> a infixl 6 #

Bitwise "xor"

bool :: a -> a -> Bool -> a #

Case analysis for the Bool type. bool x y p evaluates to x when p is False, and evaluates to y when p is True.

This is equivalent to if p then y else x; that is, one can think of it as an if-then-else construct with its arguments reordered.

Examples

Expand

Basic usage:

>>> bool "foo" "bar" True
"bar"
>>> bool "foo" "bar" False
"foo"

Confirm that bool x y p and if p then y else x are equivalent:

>>> let p = True; x = "bar"; y = "foo"
>>> bool x y p == if p then y else x
True
>>> let p = False
>>> bool x y p == if p then y else x
True

Since: base-4.7.0.0

(&) :: a -> (a -> b) -> b infixl 1 #

& is a reverse application operator. This provides notational convenience. Its precedence is one higher than that of the forward application operator $, which allows & to be nested in $.

>>> 5 & (+1) & show
"6"

Since: base-4.8.0.0

on :: (b -> b -> c) -> (a -> b) -> a -> a -> c infixl 0 #

on b u x y runs the binary function b on the results of applying unary function u to two arguments x and y. From the opposite perspective, it transforms two inputs and combines the outputs.

((+) `on` f) x y = f x + f y

Typical usage: sortBy (compare `on` fst).

Algebraic properties:

(*) `on` id = (*) -- (if (*) ∉ {⊥, const ⊥})

```
((*) `on` f) `on` g = (*) `on` (f . g)
```
```
flip on f . flip on g = flip on (g . f)
```

fix :: (a -> a) -> a #

fix f is the least fixed point of the function f, i.e. the least defined x such that f x = x.

For example, we can write the factorial function using direct recursion as

>>> let fac n = if n <= 1 then 1 else n * fac (n-1) in fac 5
120

This uses the fact that Haskell’s let introduces recursive bindings. We can rewrite this definition using fix,

>>> fix (\rec n -> if n <= 1 then 1 else n * rec (n-1)) 5
120

Instead of making a recursive call, we introduce a dummy parameter rec; when used within fix, this parameter then refers to fix' argument, hence the recursion is reintroduced.

void :: Functor f => f a -> f () #

void value discards or ignores the result of evaluation, such as the return value of an IO action.

Examples

Expand

Replace the contents of a Maybe Int with unit:

>>> void Nothing
Nothing
>>> void (Just 3)
Just ()

Replace the contents of an Either Int Int with unit, resulting in an Either Int '()':

>>> void (Left 8675309)
Left 8675309
>>> void (Right 8675309)
Right ()

Replace every element of a list with unit:

>>> void [1,2,3]
[(),(),()]

Replace the second element of a pair with unit:

>>> void (1,2)
(1,())

Discard the result of an IO action:

>>> mapM print [1,2]
1
2
[(),()]
>>> void $ mapM print [1,2]
1
2

($>) :: Functor f => f a -> b -> f b infixl 4 #

Flipped version of <$.

Examples

Expand

Replace the contents of a Maybe Int with a constant String:

>>> Nothing $> "foo"
Nothing
>>> Just 90210 $> "foo"
Just "foo"

Replace the contents of an Either Int Int with a constant String, resulting in an Either Int String:

>>> Left 8675309 $> "foo"
Left 8675309
>>> Right 8675309 $> "foo"
Right "foo"

Replace each element of a list with a constant String:

>>> [1,2,3] $> "foo"
["foo","foo","foo"]

Replace the second element of a pair with a constant String:

>>> (1,2) $> "foo"
(1,"foo")

Since: base-4.7.0.0

(<&>) :: Functor f => f a -> (a -> b) -> f b infixl 1 #

Flipped version of <$>.

(<&>) = flip fmap

Examples

Expand

Apply (+1) to a list, a Just and a Right:

>>> Just 2 <&> (+1)
Just 3

>>> [1,2,3] <&> (+1)
[2,3,4]

>>> Right 3 <&> (+1)
Right 4

Since: base-4.11.0.0

(<$>) :: Functor f => (a -> b) -> f a -> f b infixl 4 #

An infix synonym for fmap.

The name of this operator is an allusion to $. Note the similarities between their types:

 ($)  ::              (a -> b) ->   a ->   b
(<$>) :: Functor f => (a -> b) -> f a -> f b

Whereas $ is function application, <$> is function application lifted over a Functor.

Examples

Expand

Convert from a Maybe Int to a Maybe String using show:

>>> show <$> Nothing
Nothing
>>> show <$> Just 3
Just "3"

Convert from an Either Int Int to an Either Int String using show:

>>> show <$> Left 17
Left 17
>>> show <$> Right 17
Right "17"

Double each element of a list:

>>> (*2) <$> [1,2,3]
[2,4,6]

Apply even to the second element of a pair:

>>> even <$> (2,2)
(2,True)

lcm :: Integral a => a -> a -> a #

lcm x y is the smallest positive integer that both x and y divide.

gcd :: Integral a => a -> a -> a #

gcd x y is the non-negative factor of both x and y of which every common factor of x and y is also a factor; for example gcd 4 2 = 2, gcd (-4) 6 = 2, gcd 0 4 = 4. gcd 0 0 = 0. (That is, the common divisor that is "greatest" in the divisibility preordering.)

Note: Since for signed fixed-width integer types, abs minBound < 0, the result may be negative if one of the arguments is minBound (and necessarily is if the other is 0 or minBound) for such types.

(^^) :: (Fractional a, Integral b) => a -> b -> a infixr 8 #

raise a number to an integral power

(^) :: (Num a, Integral b) => a -> b -> a infixr 8 #

raise a number to a non-negative integral power

odd :: Integral a => a -> Bool #

even :: Integral a => a -> Bool #

denominator :: Ratio a -> a #

Extract the denominator of the ratio in reduced form: the numerator and denominator have no common factor and the denominator is positive.

numerator :: Ratio a -> a #

Extract the numerator of the ratio in reduced form: the numerator and denominator have no common factor and the denominator is positive.

chr :: Int -> Char #

The toEnum method restricted to the type Char.

unzip3 :: [(a, b, c)] -> ([a], [b], [c]) #

The unzip3 function takes a list of triples and returns three lists, analogous to unzip.

unzip :: [(a, b)] -> ([a], [b]) #

unzip transforms a list of pairs into a list of first components and a list of second components.

zipWith :: (a -> b -> c) -> [a] -> [b] -> [c] #

zipWith generalises zip by zipping with the function given as the first argument, instead of a tupling function. For example, zipWith (+) is applied to two lists to produce the list of corresponding sums.

zipWith is right-lazy:

zipWith f [] _|_ = []

zip3 :: [a] -> [b] -> [c] -> [(a, b, c)] #

zip3 takes three lists and returns a list of triples, analogous to zip.

reverse :: [a] -> [a] #

reverse xs returns the elements of xs in reverse order. xs must be finite.

break :: (a -> Bool) -> [a] -> ([a], [a]) #

break, applied to a predicate p and a list xs, returns a tuple where first element is longest prefix (possibly empty) of xs of elements that do not satisfy p and second element is the remainder of the list:

break (> 3) [1,2,3,4,1,2,3,4] == ([1,2,3],[4,1,2,3,4])
break (< 9) [1,2,3] == ([],[1,2,3])
break (> 9) [1,2,3] == ([1,2,3],[])

break p is equivalent to span (not . p).

splitAt :: Int -> [a] -> ([a], [a]) #

splitAt n xs returns a tuple where first element is xs prefix of length n and second element is the remainder of the list:

splitAt 6 "Hello World!" == ("Hello ","World!")
splitAt 3 [1,2,3,4,5] == ([1,2,3],[4,5])
splitAt 1 [1,2,3] == ([1],[2,3])
splitAt 3 [1,2,3] == ([1,2,3],[])
splitAt 4 [1,2,3] == ([1,2,3],[])
splitAt 0 [1,2,3] == ([],[1,2,3])
splitAt (-1) [1,2,3] == ([],[1,2,3])

It is equivalent to (take n xs, drop n xs) when n is not _|_ (splitAt _|_ xs = _|_). splitAt is an instance of the more general genericSplitAt, in which n may be of any integral type.

drop :: Int -> [a] -> [a] #

drop n xs returns the suffix of xs after the first n elements, or [] if n > length xs:

drop 6 "Hello World!" == "World!"
drop 3 [1,2,3,4,5] == [4,5]
drop 3 [1,2] == []
drop 3 [] == []
drop (-1) [1,2] == [1,2]
drop 0 [1,2] == [1,2]

It is an instance of the more general genericDrop, in which n may be of any integral type.

take :: Int -> [a] -> [a] #

take n, applied to a list xs, returns the prefix of xs of length n, or xs itself if n > length xs:

take 5 "Hello World!" == "Hello"
take 3 [1,2,3,4,5] == [1,2,3]
take 3 [1,2] == [1,2]
take 3 [] == []
take (-1) [1,2] == []
take 0 [1,2] == []

It is an instance of the more general genericTake, in which n may be of any integral type.

dropWhile :: (a -> Bool) -> [a] -> [a] #

dropWhile p xs returns the suffix remaining after takeWhile p xs:

dropWhile (< 3) [1,2,3,4,5,1,2,3] == [3,4,5,1,2,3]
dropWhile (< 9) [1,2,3] == []
dropWhile (< 0) [1,2,3] == [1,2,3]

takeWhile :: (a -> Bool) -> [a] -> [a] #

takeWhile, applied to a predicate p and a list xs, returns the longest prefix (possibly empty) of xs of elements that satisfy p:

takeWhile (< 3) [1,2,3,4,1,2,3,4] == [1,2]
takeWhile (< 9) [1,2,3] == [1,2,3]
takeWhile (< 0) [1,2,3] == []

cycle :: [a] -> [a] #

cycle ties a finite list into a circular one, or equivalently, the infinite repetition of the original list. It is the identity on infinite lists.

replicate :: Int -> a -> [a] #

replicate n x is a list of length n with x the value of every element. It is an instance of the more general genericReplicate, in which n may be of any integral type.

repeat :: a -> [a] #

repeat x is an infinite list, with x the value of every element.

iterate :: (a -> a) -> a -> [a] #

iterate f x returns an infinite list of repeated applications of f to x:

iterate f x == [x, f x, f (f x), ...]

Note that iterate is lazy, potentially leading to thunk build-up if the consumer doesn't force each iterate. See 'iterate\'' for a strict variant of this function.

scanr :: (a -> b -> b) -> b -> [a] -> [b] #

scanr is the right-to-left dual of scanl. Note that

head (scanr f z xs) == foldr f z xs.

scanl :: (b -> a -> b) -> b -> [a] -> [b] #

scanl is similar to foldl, but returns a list of successive reduced values from the left:

scanl f z [x1, x2, ...] == [z, z `f` x1, (z `f` x1) `f` x2, ...]

Note that

last (scanl f z xs) == foldl f z xs.

mapMaybe :: (a -> Maybe b) -> [a] -> [b] #

The mapMaybe function is a version of map which can throw out elements. In particular, the functional argument returns something of type Maybe b. If this is Nothing, no element is added on to the result list. If it is Just b, then b is included in the result list.

Examples

Expand

Using mapMaybe f x is a shortcut for catMaybes $ map f x in most cases:

>>> import Text.Read ( readMaybe )
>>> let readMaybeInt = readMaybe :: String -> Maybe Int
>>> mapMaybe readMaybeInt ["1", "Foo", "3"]
[1,3]
>>> catMaybes $ map readMaybeInt ["1", "Foo", "3"]
[1,3]

If we map the Just constructor, the entire list should be returned:

>>> mapMaybe Just [1,2,3]
[1,2,3]

catMaybes :: [Maybe a] -> [a] #

The catMaybes function takes a list of Maybes and returns a list of all the Just values.

Examples

Expand

Basic usage:

>>> catMaybes [Just 1, Nothing, Just 3]
[1,3]

When constructing a list of Maybe values, catMaybes can be used to return all of the "success" results (if the list is the result of a map, then mapMaybe would be more appropriate):

>>> import Text.Read ( readMaybe )
>>> [readMaybe x :: Maybe Int | x <- ["1", "Foo", "3"] ]
[Just 1,Nothing,Just 3]
>>> catMaybes $ [readMaybe x :: Maybe Int | x <- ["1", "Foo", "3"] ]
[1,3]

listToMaybe :: [a] -> Maybe a #

The listToMaybe function returns Nothing on an empty list or Just a where a is the first element of the list.

Examples

Expand

Basic usage:

>>> listToMaybe []
Nothing

>>> listToMaybe [9]
Just 9

>>> listToMaybe [1,2,3]
Just 1

Composing maybeToList with listToMaybe should be the identity on singleton/empty lists:

>>> maybeToList $ listToMaybe [5]
[5]
>>> maybeToList $ listToMaybe []
[]

But not on lists with more than one element:

>>> maybeToList $ listToMaybe [1,2,3]
[1]

maybeToList :: Maybe a -> [a] #

The maybeToList function returns an empty list when given Nothing or a singleton list when not given Nothing.

Examples

Expand

Basic usage:

>>> maybeToList (Just 7)
[7]

>>> maybeToList Nothing
[]

One can use maybeToList to avoid pattern matching when combined with a function that (safely) works on lists:

>>> import Text.Read ( readMaybe )
>>> sum $ maybeToList (readMaybe "3")
3
>>> sum $ maybeToList (readMaybe "")
0

fromMaybe :: a -> Maybe a -> a #

The fromMaybe function takes a default value and and Maybe value. If the Maybe is Nothing, it returns the default values; otherwise, it returns the value contained in the Maybe.

Examples

Expand

Basic usage:

>>> fromMaybe "" (Just "Hello, World!")
"Hello, World!"

>>> fromMaybe "" Nothing
""

Read an integer from a string using readMaybe. If we fail to parse an integer, we want to return 0 by default:

>>> import Text.Read ( readMaybe )
>>> fromMaybe 0 (readMaybe "5")
5
>>> fromMaybe 0 (readMaybe "")
0

isNothing :: Maybe a -> Bool #

The isNothing function returns True iff its argument is Nothing.

Examples

Expand

Basic usage:

>>> isNothing (Just 3)
False

>>> isNothing (Just ())
False

>>> isNothing Nothing
True

Only the outer constructor is taken into consideration:

>>> isNothing (Just Nothing)
False

isJust :: Maybe a -> Bool #

The isJust function returns True iff its argument is of the form Just _.

Examples

Expand

Basic usage:

>>> isJust (Just 3)
True

>>> isJust (Just ())
True

>>> isJust Nothing
False

Only the outer constructor is taken into consideration:

>>> isJust (Just Nothing)
True

maybe :: b -> (a -> b) -> Maybe a -> b #

The maybe function takes a default value, a function, and a Maybe value. If the Maybe value is Nothing, the function returns the default value. Otherwise, it applies the function to the value inside the Just and returns the result.

Examples

Expand

Basic usage:

>>> maybe False odd (Just 3)
True

>>> maybe False odd Nothing
False

Read an integer from a string using readMaybe. If we succeed, return twice the integer; that is, apply (*2) to it. If instead we fail to parse an integer, return 0 by default:

>>> import Text.Read ( readMaybe )
>>> maybe 0 (*2) (readMaybe "5")
10
>>> maybe 0 (*2) (readMaybe "")
0

Apply show to a Maybe Int. If we have Just n, we want to show the underlying Int n. But if we have Nothing, we return the empty string instead of (for example) "Nothing":

>>> maybe "" show (Just 5)
"5"
>>> maybe "" show Nothing
""

swap :: (a, b) -> (b, a) #

Swap the components of a pair.

uncurry :: (a -> b -> c) -> (a, b) -> c #

uncurry converts a curried function to a function on pairs.

Examples

Expand

>>> uncurry (+) (1,2)
3

>>> uncurry ($) (show, 1)
"1"

>>> map (uncurry max) [(1,2), (3,4), (6,8)]
[2,4,8]

curry :: ((a, b) -> c) -> a -> b -> c #

curry converts an uncurried function to a curried function.

Examples

Expand

>>> curry fst 1 2
1

data MVar a #

An MVar (pronounced "em-var") is a synchronising variable, used for communication between concurrent threads. It can be thought of as a box, which may be empty or full.

Instances

NFData1 MVar	Since: deepseq-1.4.3.0
Instance details Defined in Control.DeepSeq Methods liftRnf :: (a -> ()) -> MVar a -> () #
Eq (MVar a)	Since: base-4.1.0.0
Instance details Defined in GHC.MVar Methods (==) :: MVar a -> MVar a -> Bool # (/=) :: MVar a -> MVar a -> Bool #
NFData (MVar a)	NOTE: Only strict in the reference and not the referenced value. Since: deepseq-1.4.2.0
Instance details Defined in Control.DeepSeq Methods rnf :: MVar a -> () #

subtract :: Num a => a -> a -> a #

the same as flip (-).

Because - is treated specially in the Haskell grammar, (- e) is not a section, but an application of prefix negation. However, (subtract exp) is equivalent to the disallowed section.

currentCallStack :: IO [String] #

Returns a [String] representing the current call stack. This can be useful for debugging.

The implementation uses the call-stack simulation maintained by the profiler, so it only works if the program was compiled with -prof and contains suitable SCC annotations (e.g. by using -fprof-auto). Otherwise, the list returned is likely to be empty or uninformative.

Since: base-4.5.0.0

asTypeOf :: a -> a -> a #

asTypeOf is a type-restricted version of const. It is usually used as an infix operator, and its typing forces its first argument (which is usually overloaded) to have the same type as the second.

flip :: (a -> b -> c) -> b -> a -> c #

flip f takes its (first) two arguments in the reverse order of f.

>>> flip (++) "hello" "world"
"worldhello"

(.) :: (b -> c) -> (a -> b) -> a -> c infixr 9 #

Function composition.

const :: a -> b -> a #

const x is a unary function which evaluates to x for all inputs.

>>> const 42 "hello"
42

>>> map (const 42) [0..3]
[42,42,42,42]

id :: a -> a #

Identity function.

id x = x

ord :: Char -> Int #

The fromEnum method restricted to the type Char.

ap :: Monad m => m (a -> b) -> m a -> m b #

In many situations, the liftM operations can be replaced by uses of ap, which promotes function application.

return f `ap` x1 `ap` ... `ap` xn

is equivalent to

liftMn f x1 x2 ... xn

liftM5 :: Monad m => (a1 -> a2 -> a3 -> a4 -> a5 -> r) -> m a1 -> m a2 -> m a3 -> m a4 -> m a5 -> m r #

Promote a function to a monad, scanning the monadic arguments from left to right (cf. liftM2).

liftM4 :: Monad m => (a1 -> a2 -> a3 -> a4 -> r) -> m a1 -> m a2 -> m a3 -> m a4 -> m r #

Promote a function to a monad, scanning the monadic arguments from left to right (cf. liftM2).

liftM3 :: Monad m => (a1 -> a2 -> a3 -> r) -> m a1 -> m a2 -> m a3 -> m r #

Promote a function to a monad, scanning the monadic arguments from left to right (cf. liftM2).

liftM2 :: Monad m => (a1 -> a2 -> r) -> m a1 -> m a2 -> m r #

Promote a function to a monad, scanning the monadic arguments from left to right. For example,

liftM2 (+) [0,1] [0,2] = [0,2,1,3]
liftM2 (+) (Just 1) Nothing = Nothing

when :: Applicative f => Bool -> f () -> f () #

Conditional execution of Applicative expressions. For example,

when debug (putStrLn "Debugging")

will output the string Debugging if the Boolean value debug is True, and otherwise do nothing.

(=<<) :: Monad m => (a -> m b) -> m a -> m b infixr 1 #

Same as >>=, but with the arguments interchanged.

liftA3 :: Applicative f => (a -> b -> c -> d) -> f a -> f b -> f c -> f d #

Lift a ternary function to actions.

(<**>) :: Applicative f => f a -> f (a -> b) -> f b infixl 4 #

A variant of <*> with the arguments reversed.

class Applicative f => Alternative (f :: Type -> Type) where #

A monoid on applicative functors.

If defined, some and many should be the least solutions of the equations:

```
some v = (:) <$> v <*> many v
```
```
many v = some v <|> pure []
```

Minimal complete definition

empty, (<|>)

Methods

empty :: f a #

The identity of <|>

(<|>) :: f a -> f a -> f a infixl 3 #

An associative binary operation

some :: f a -> f [a] #

One or more.

many :: f a -> f [a] #

Zero or more.

Instances

Alternative []	Since: base-2.1
Instance details Defined in GHC.Base Methods empty :: [a] # (<\|>) :: [a] -> [a] -> [a] # some :: [a] -> [[a]] # many :: [a] -> [[a]] #
Alternative Maybe	Since: base-2.1
Instance details Defined in GHC.Base Methods empty :: Maybe a # (<\|>) :: Maybe a -> Maybe a -> Maybe a # some :: Maybe a -> Maybe [a] # many :: Maybe a -> Maybe [a] #
Alternative IO	Since: base-4.9.0.0
Instance details Defined in GHC.Base Methods empty :: IO a # (<\|>) :: IO a -> IO a -> IO a # some :: IO a -> IO [a] # many :: IO a -> IO [a] #
Alternative Option	Since: base-4.9.0.0
Instance details Defined in Data.Semigroup Methods empty :: Option a # (<\|>) :: Option a -> Option a -> Option a # some :: Option a -> Option [a] # many :: Option a -> Option [a] #
Alternative ZipList	Since: base-4.11.0.0
Instance details Defined in Control.Applicative Methods empty :: ZipList a # (<\|>) :: ZipList a -> ZipList a -> ZipList a # some :: ZipList a -> ZipList [a] # many :: ZipList a -> ZipList [a] #
Alternative STM	Since: base-4.8.0.0
Instance details Defined in GHC.Conc.Sync Methods empty :: STM a # (<\|>) :: STM a -> STM a -> STM a # some :: STM a -> STM [a] # many :: STM a -> STM [a] #
Alternative ReadP	Since: base-4.6.0.0
Instance details Defined in Text.ParserCombinators.ReadP Methods empty :: ReadP a # (<\|>) :: ReadP a -> ReadP a -> ReadP a # some :: ReadP a -> ReadP [a] # many :: ReadP a -> ReadP [a] #
Alternative Seq	Since: containers-0.5.4
Instance details Defined in Data.Sequence.Internal Methods empty :: Seq a # (<\|>) :: Seq a -> Seq a -> Seq a # some :: Seq a -> Seq [a] # many :: Seq a -> Seq [a] #
Alternative Vector
Instance details Defined in Data.Vector Methods empty :: Vector a # (<\|>) :: Vector a -> Vector a -> Vector a # some :: Vector a -> Vector [a] # many :: Vector a -> Vector [a] #
Alternative P	Since: base-4.5.0.0
Instance details Defined in Text.ParserCombinators.ReadP Methods empty :: P a # (<\|>) :: P a -> P a -> P a # some :: P a -> P [a] # many :: P a -> P [a] #
Alternative (U1 :: Type -> Type)	Since: base-4.9.0.0
Instance details Defined in GHC.Generics Methods empty :: U1 a # (<\|>) :: U1 a -> U1 a -> U1 a # some :: U1 a -> U1 [a] # many :: U1 a -> U1 [a] #
MonadPlus m => Alternative (WrappedMonad m)	Since: base-2.1
Instance details Defined in Control.Applicative Methods empty :: WrappedMonad m a # (<\|>) :: WrappedMonad m a -> WrappedMonad m a -> WrappedMonad m a # some :: WrappedMonad m a -> WrappedMonad m [a] # many :: WrappedMonad m a -> WrappedMonad m [a] #
ArrowPlus a => Alternative (ArrowMonad a)	Since: base-4.6.0.0
Instance details Defined in Control.Arrow Methods empty :: ArrowMonad a a0 # (<\|>) :: ArrowMonad a a0 -> ArrowMonad a a0 -> ArrowMonad a a0 # some :: ArrowMonad a a0 -> ArrowMonad a [a0] # many :: ArrowMonad a a0 -> ArrowMonad a [a0] #
Alternative (Proxy :: Type -> Type)	Since: base-4.9.0.0
Instance details Defined in Data.Proxy Methods empty :: Proxy a # (<\|>) :: Proxy a -> Proxy a -> Proxy a # some :: Proxy a -> Proxy [a] # many :: Proxy a -> Proxy [a] #
(Functor m, Monad m) => Alternative (MaybeT m)
Instance details Defined in Control.Monad.Trans.Maybe Methods empty :: MaybeT m a # (<\|>) :: MaybeT m a -> MaybeT m a -> MaybeT m a # some :: MaybeT m a -> MaybeT m [a] # many :: MaybeT m a -> MaybeT m [a] #
Alternative f => Alternative (Rec1 f)	Since: base-4.9.0.0
Instance details Defined in GHC.Generics Methods empty :: Rec1 f a # (<\|>) :: Rec1 f a -> Rec1 f a -> Rec1 f a # some :: Rec1 f a -> Rec1 f [a] # many :: Rec1 f a -> Rec1 f [a] #
(ArrowZero a, ArrowPlus a) => Alternative (WrappedArrow a b)	Since: base-2.1
Instance details Defined in Control.Applicative Methods empty :: WrappedArrow a b a0 # (<\|>) :: WrappedArrow a b a0 -> WrappedArrow a b a0 -> WrappedArrow a b a0 # some :: WrappedArrow a b a0 -> WrappedArrow a b [a0] # many :: WrappedArrow a b a0 -> WrappedArrow a b [a0] #
Alternative f => Alternative (Ap f)	Since: base-4.12.0.0
Instance details Defined in Data.Monoid Methods empty :: Ap f a # (<\|>) :: Ap f a -> Ap f a -> Ap f a # some :: Ap f a -> Ap f [a] # many :: Ap f a -> Ap f [a] #
Alternative f => Alternative (Alt f)	Since: base-4.8.0.0
Instance details Defined in Data.Semigroup.Internal Methods empty :: Alt f a # (<\|>) :: Alt f a -> Alt f a -> Alt f a # some :: Alt f a -> Alt f [a] # many :: Alt f a -> Alt f [a] #
(Functor m, Monad m, Monoid e) => Alternative (ExceptT e m)
Instance details Defined in Control.Monad.Trans.Except Methods empty :: ExceptT e m a # (<\|>) :: ExceptT e m a -> ExceptT e m a -> ExceptT e m a # some :: ExceptT e m a -> ExceptT e m [a] # many :: ExceptT e m a -> ExceptT e m [a] #
Alternative m => Alternative (IdentityT m)
Instance details Defined in Control.Monad.Trans.Identity Methods empty :: IdentityT m a # (<\|>) :: IdentityT m a -> IdentityT m a -> IdentityT m a # some :: IdentityT m a -> IdentityT m [a] # many :: IdentityT m a -> IdentityT m [a] #
(Functor m, Monad m, Error e) => Alternative (ErrorT e m)
Instance details Defined in Control.Monad.Trans.Error Methods empty :: ErrorT e m a # (<\|>) :: ErrorT e m a -> ErrorT e m a -> ErrorT e m a # some :: ErrorT e m a -> ErrorT e m [a] # many :: ErrorT e m a -> ErrorT e m [a] #
(Functor m, MonadPlus m) => Alternative (StateT s m)
Instance details Defined in Control.Monad.Trans.State.Strict Methods empty :: StateT s m a # (<\|>) :: StateT s m a -> StateT s m a -> StateT s m a # some :: StateT s m a -> StateT s m [a] # many :: StateT s m a -> StateT s m [a] #
(Alternative f, Alternative g) => Alternative (f :*: g)	Since: base-4.9.0.0
Instance details Defined in GHC.Generics Methods empty :: (f :: g) a # (<\|>) :: (f :: g) a -> (f :: g) a -> (f :: g) a # some :: (f :: g) a -> (f :: g) [a] # many :: (f :: g) a -> (f :: g) [a] #
Alternative m => Alternative (ReaderT r m)
Instance details Defined in Control.Monad.Trans.Reader Methods empty :: ReaderT r m a # (<\|>) :: ReaderT r m a -> ReaderT r m a -> ReaderT r m a # some :: ReaderT r m a -> ReaderT r m [a] # many :: ReaderT r m a -> ReaderT r m [a] #
Alternative f => Alternative (M1 i c f)	Since: base-4.9.0.0
Instance details Defined in GHC.Generics Methods empty :: M1 i c f a # (<\|>) :: M1 i c f a -> M1 i c f a -> M1 i c f a # some :: M1 i c f a -> M1 i c f [a] # many :: M1 i c f a -> M1 i c f [a] #
(Alternative f, Applicative g) => Alternative (f :.: g)	Since: base-4.9.0.0
Instance details Defined in GHC.Generics Methods empty :: (f :.: g) a # (<\|>) :: (f :.: g) a -> (f :.: g) a -> (f :.: g) a # some :: (f :.: g) a -> (f :.: g) [a] # many :: (f :.: g) a -> (f :.: g) [a] #
(Alternative f, Applicative g) => Alternative (Compose f g)	Since: base-4.9.0.0
Instance details Defined in Data.Functor.Compose Methods empty :: Compose f g a # (<\|>) :: Compose f g a -> Compose f g a -> Compose f g a # some :: Compose f g a -> Compose f g [a] # many :: Compose f g a -> Compose f g [a] #

class (Alternative m, Monad m) => MonadPlus (m :: Type -> Type) where #

Monads that also support choice and failure.

Minimal complete definition

Nothing

Methods

mzero :: m a #

The identity of mplus. It should also satisfy the equations

mzero >>= f  =  mzero
v >> mzero   =  mzero

The default definition is

mzero = empty

mplus :: m a -> m a -> m a #

An associative operation. The default definition is

mplus = (<|>)

Instances

MonadPlus []	Since: base-2.1
Instance details Defined in GHC.Base Methods mzero :: [a] # mplus :: [a] -> [a] -> [a] #
MonadPlus Maybe	Since: base-2.1
Instance details Defined in GHC.Base Methods mzero :: Maybe a # mplus :: Maybe a -> Maybe a -> Maybe a #
MonadPlus IO	Since: base-4.9.0.0
Instance details Defined in GHC.Base Methods mzero :: IO a # mplus :: IO a -> IO a -> IO a #
MonadPlus Option	Since: base-4.9.0.0
Instance details Defined in Data.Semigroup Methods mzero :: Option a # mplus :: Option a -> Option a -> Option a #
MonadPlus STM	Since: base-4.3.0.0
Instance details Defined in GHC.Conc.Sync Methods mzero :: STM a # mplus :: STM a -> STM a -> STM a #
MonadPlus ReadP	Since: base-2.1
Instance details Defined in Text.ParserCombinators.ReadP Methods mzero :: ReadP a # mplus :: ReadP a -> ReadP a -> ReadP a #
MonadPlus Seq
Instance details Defined in Data.Sequence.Internal Methods mzero :: Seq a # mplus :: Seq a -> Seq a -> Seq a #
MonadPlus Vector
Instance details Defined in Data.Vector Methods mzero :: Vector a # mplus :: Vector a -> Vector a -> Vector a #
MonadPlus P	Since: base-2.1
Instance details Defined in Text.ParserCombinators.ReadP Methods mzero :: P a # mplus :: P a -> P a -> P a #
MonadPlus (U1 :: Type -> Type)	Since: base-4.9.0.0
Instance details Defined in GHC.Generics Methods mzero :: U1 a # mplus :: U1 a -> U1 a -> U1 a #
(ArrowApply a, ArrowPlus a) => MonadPlus (ArrowMonad a)	Since: base-4.6.0.0
Instance details Defined in Control.Arrow Methods mzero :: ArrowMonad a a0 # mplus :: ArrowMonad a a0 -> ArrowMonad a a0 -> ArrowMonad a a0 #
MonadPlus (Proxy :: Type -> Type)	Since: base-4.9.0.0
Instance details Defined in Data.Proxy Methods mzero :: Proxy a # mplus :: Proxy a -> Proxy a -> Proxy a #
Monad m => MonadPlus (MaybeT m)
Instance details Defined in Control.Monad.Trans.Maybe Methods mzero :: MaybeT m a # mplus :: MaybeT m a -> MaybeT m a -> MaybeT m a #
MonadPlus f => MonadPlus (Rec1 f)	Since: base-4.9.0.0
Instance details Defined in GHC.Generics Methods mzero :: Rec1 f a # mplus :: Rec1 f a -> Rec1 f a -> Rec1 f a #
MonadPlus f => MonadPlus (Ap f)	Since: base-4.12.0.0
Instance details Defined in Data.Monoid Methods mzero :: Ap f a # mplus :: Ap f a -> Ap f a -> Ap f a #
MonadPlus f => MonadPlus (Alt f)	Since: base-4.8.0.0
Instance details Defined in Data.Semigroup.Internal Methods mzero :: Alt f a # mplus :: Alt f a -> Alt f a -> Alt f a #
(Monad m, Monoid e) => MonadPlus (ExceptT e m)
Instance details Defined in Control.Monad.Trans.Except Methods mzero :: ExceptT e m a # mplus :: ExceptT e m a -> ExceptT e m a -> ExceptT e m a #
MonadPlus m => MonadPlus (IdentityT m)
Instance details Defined in Control.Monad.Trans.Identity Methods mzero :: IdentityT m a # mplus :: IdentityT m a -> IdentityT m a -> IdentityT m a #
(Monad m, Error e) => MonadPlus (ErrorT e m)
Instance details Defined in Control.Monad.Trans.Error Methods mzero :: ErrorT e m a # mplus :: ErrorT e m a -> ErrorT e m a -> ErrorT e m a #
MonadPlus m => MonadPlus (StateT s m)
Instance details Defined in Control.Monad.Trans.State.Strict Methods mzero :: StateT s m a # mplus :: StateT s m a -> StateT s m a -> StateT s m a #
(MonadPlus f, MonadPlus g) => MonadPlus (f :*: g)	Since: base-4.9.0.0
Instance details Defined in GHC.Generics Methods mzero :: (f :: g) a # mplus :: (f :: g) a -> (f :: g) a -> (f :: g) a #
MonadPlus m => MonadPlus (ReaderT r m)
Instance details Defined in Control.Monad.Trans.Reader Methods mzero :: ReaderT r m a # mplus :: ReaderT r m a -> ReaderT r m a -> ReaderT r m a #
MonadPlus f => MonadPlus (M1 i c f)	Since: base-4.9.0.0
Instance details Defined in GHC.Generics Methods mzero :: M1 i c f a # mplus :: M1 i c f a -> M1 i c f a -> M1 i c f a #

data NonEmpty a #

Non-empty (and non-strict) list type.

Since: base-4.9.0.0

Constructors

a :| [a] infixr 5

Instances

Monad NonEmpty	Since: base-4.9.0.0
Instance details Defined in GHC.Base Methods (>>=) :: NonEmpty a -> (a -> NonEmpty b) -> NonEmpty b # (>>) :: NonEmpty a -> NonEmpty b -> NonEmpty b # return :: a -> NonEmpty a # fail :: String -> NonEmpty a #
Functor NonEmpty	Since: base-4.9.0.0
Instance details Defined in GHC.Base Methods fmap :: (a -> b) -> NonEmpty a -> NonEmpty b # (<$) :: a -> NonEmpty b -> NonEmpty a #
Applicative NonEmpty	Since: base-4.9.0.0
Instance details Defined in GHC.Base Methods pure :: a -> NonEmpty a # (<>) :: NonEmpty (a -> b) -> NonEmpty a -> NonEmpty b # liftA2 :: (a -> b -> c) -> NonEmpty a -> NonEmpty b -> NonEmpty c # (>) :: NonEmpty a -> NonEmpty b -> NonEmpty b # (<*) :: NonEmpty a -> NonEmpty b -> NonEmpty a #
Foldable NonEmpty	Since: base-4.9.0.0
Instance details Defined in Data.Foldable Methods fold :: Monoid m => NonEmpty m -> m # foldMap :: Monoid m => (a -> m) -> NonEmpty a -> m # foldr :: (a -> b -> b) -> b -> NonEmpty a -> b # foldr' :: (a -> b -> b) -> b -> NonEmpty a -> b # foldl :: (b -> a -> b) -> b -> NonEmpty a -> b # foldl' :: (b -> a -> b) -> b -> NonEmpty a -> b # foldr1 :: (a -> a -> a) -> NonEmpty a -> a # foldl1 :: (a -> a -> a) -> NonEmpty a -> a # toList :: NonEmpty a -> [a] # null :: NonEmpty a -> Bool # length :: NonEmpty a -> Int # elem :: Eq a => a -> NonEmpty a -> Bool # maximum :: Ord a => NonEmpty a -> a # minimum :: Ord a => NonEmpty a -> a # sum :: Num a => NonEmpty a -> a # product :: Num a => NonEmpty a -> a #
Traversable NonEmpty	Since: base-4.9.0.0
Instance details Defined in Data.Traversable Methods traverse :: Applicative f => (a -> f b) -> NonEmpty a -> f (NonEmpty b) # sequenceA :: Applicative f => NonEmpty (f a) -> f (NonEmpty a) # mapM :: Monad m => (a -> m b) -> NonEmpty a -> m (NonEmpty b) # sequence :: Monad m => NonEmpty (m a) -> m (NonEmpty a) #
NFData1 NonEmpty	Since: deepseq-1.4.3.0
Instance details Defined in Control.DeepSeq Methods liftRnf :: (a -> ()) -> NonEmpty a -> () #
IsList (NonEmpty a)	Since: base-4.9.0.0
Instance details Defined in GHC.Exts Associated Types type Item (NonEmpty a) :: Type # Methods fromList :: [Item (NonEmpty a)] -> NonEmpty a # fromListN :: Int -> [Item (NonEmpty a)] -> NonEmpty a # toList :: NonEmpty a -> [Item (NonEmpty a)] #
Eq a => Eq (NonEmpty a)	Since: base-4.9.0.0
Instance details Defined in GHC.Base Methods (==) :: NonEmpty a -> NonEmpty a -> Bool # (/=) :: NonEmpty a -> NonEmpty a -> Bool #
Ord a => Ord (NonEmpty a)	Since: base-4.9.0.0
Instance details Defined in GHC.Base Methods compare :: NonEmpty a -> NonEmpty a -> Ordering # (<) :: NonEmpty a -> NonEmpty a -> Bool # (<=) :: NonEmpty a -> NonEmpty a -> Bool # (>) :: NonEmpty a -> NonEmpty a -> Bool # (>=) :: NonEmpty a -> NonEmpty a -> Bool # max :: NonEmpty a -> NonEmpty a -> NonEmpty a # min :: NonEmpty a -> NonEmpty a -> NonEmpty a #
Read a => Read (NonEmpty a)	Since: base-4.11.0.0
Instance details Defined in GHC.Read Methods readsPrec :: Int -> ReadS (NonEmpty a) # readList :: ReadS [NonEmpty a] # readPrec :: ReadPrec (NonEmpty a) # readListPrec :: ReadPrec [NonEmpty a] #
Show a => Show (NonEmpty a)	Since: base-4.11.0.0
Instance details Defined in GHC.Show Methods showsPrec :: Int -> NonEmpty a -> ShowS # show :: NonEmpty a -> String # showList :: [NonEmpty a] -> ShowS #
Generic (NonEmpty a)
Instance details Defined in GHC.Generics Associated Types type Rep (NonEmpty a) :: Type -> Type # Methods from :: NonEmpty a -> Rep (NonEmpty a) x # to :: Rep (NonEmpty a) x -> NonEmpty a #
Semigroup (NonEmpty a)	Since: base-4.9.0.0
Instance details Defined in GHC.Base Methods (<>) :: NonEmpty a -> NonEmpty a -> NonEmpty a # sconcat :: NonEmpty (NonEmpty a) -> NonEmpty a # stimes :: Integral b => b -> NonEmpty a -> NonEmpty a #
NFData a => NFData (NonEmpty a)	Since: deepseq-1.4.2.0
Instance details Defined in Control.DeepSeq Methods rnf :: NonEmpty a -> () #
Hashable a => Hashable (NonEmpty a)
Instance details Defined in Data.Hashable.Class Methods hashWithSalt :: Int -> NonEmpty a -> Int # hash :: NonEmpty a -> Int #
Container (NonEmpty a)
Instance details Defined in Universum.Container.Class Associated Types type Element (NonEmpty a) :: Type # Methods toList :: NonEmpty a -> [Element (NonEmpty a)] # null :: NonEmpty a -> Bool # foldr :: (Element (NonEmpty a) -> b -> b) -> b -> NonEmpty a -> b # foldl :: (b -> Element (NonEmpty a) -> b) -> b -> NonEmpty a -> b # foldl' :: (b -> Element (NonEmpty a) -> b) -> b -> NonEmpty a -> b # length :: NonEmpty a -> Int # elem :: Element (NonEmpty a) -> NonEmpty a -> Bool # maximum :: NonEmpty a -> Element (NonEmpty a) # minimum :: NonEmpty a -> Element (NonEmpty a) # foldMap :: Monoid m => (Element (NonEmpty a) -> m) -> NonEmpty a -> m # fold :: NonEmpty a -> Element (NonEmpty a) # foldr' :: (Element (NonEmpty a) -> b -> b) -> b -> NonEmpty a -> b # foldr1 :: (Element (NonEmpty a) -> Element (NonEmpty a) -> Element (NonEmpty a)) -> NonEmpty a -> Element (NonEmpty a) # foldl1 :: (Element (NonEmpty a) -> Element (NonEmpty a) -> Element (NonEmpty a)) -> NonEmpty a -> Element (NonEmpty a) # notElem :: Element (NonEmpty a) -> NonEmpty a -> Bool # all :: (Element (NonEmpty a) -> Bool) -> NonEmpty a -> Bool # any :: (Element (NonEmpty a) -> Bool) -> NonEmpty a -> Bool # and :: NonEmpty a -> Bool # or :: NonEmpty a -> Bool # find :: (Element (NonEmpty a) -> Bool) -> NonEmpty a -> Maybe (Element (NonEmpty a)) # safeHead :: NonEmpty a -> Maybe (Element (NonEmpty a)) #
One (NonEmpty a)
Instance details Defined in Universum.Container.Class Associated Types type OneItem (NonEmpty a) :: Type # Methods one :: OneItem (NonEmpty a) -> NonEmpty a #
Generic1 NonEmpty
Instance details Defined in GHC.Generics Associated Types type Rep1 NonEmpty :: k -> Type # Methods from1 :: NonEmpty a -> Rep1 NonEmpty a # to1 :: Rep1 NonEmpty a -> NonEmpty a #
Each (NonEmpty a) (NonEmpty b) a b
Instance details Defined in Lens.Micro.Internal Methods each :: Traversal (NonEmpty a) (NonEmpty b) a b #
type Rep (NonEmpty a)	Since: base-4.6.0.0
Instance details Defined in GHC.Generics type Rep (NonEmpty a) = D1 (MetaData "NonEmpty" "GHC.Base" "base" False) (C1 (MetaCons ":\|" (InfixI LeftAssociative 9) False) (S1 (MetaSel (Nothing :: Maybe Symbol) NoSourceUnpackedness NoSourceStrictness DecidedLazy) (Rec0 a) :*: S1 (MetaSel (Nothing :: Maybe Symbol) NoSourceUnpackedness NoSourceStrictness DecidedLazy) (Rec0 [a])))
type Item (NonEmpty a)
Instance details Defined in GHC.Exts type Item (NonEmpty a) = a
type Element (NonEmpty a)
Instance details Defined in Universum.Container.Class type Element (NonEmpty a) = ElementDefault (NonEmpty a)
type OneItem (NonEmpty a)
Instance details Defined in Universum.Container.Class type OneItem (NonEmpty a) = a
type Rep1 NonEmpty	Since: base-4.6.0.0
Instance details Defined in GHC.Generics type Rep1 NonEmpty = D1 (MetaData "NonEmpty" "GHC.Base" "base" False) (C1 (MetaCons ":\|" (InfixI LeftAssociative 9) False) (S1 (MetaSel (Nothing :: Maybe Symbol) NoSourceUnpackedness NoSourceStrictness DecidedLazy) Par1 :*: S1 (MetaSel (Nothing :: Maybe Symbol) NoSourceUnpackedness NoSourceStrictness DecidedLazy) (Rec1 [])))

type String = [Char] #

A String is a list of characters. String constants in Haskell are values of type String.

getCallStack :: CallStack -> [([Char], SrcLoc)] #

Extract a list of call-sites from the CallStack.

The list is ordered by most recent call.

Since: base-4.8.1.0

type HasCallStack = ?callStack :: CallStack #

Request a CallStack.

NOTE: The implicit parameter ?callStack :: CallStack is an implementation detail and should not be considered part of the CallStack API, we may decide to change the implementation in the future.

Since: base-4.9.0.0

stimesIdempotentMonoid :: (Integral b, Monoid a) => b -> a -> a #

This is a valid definition of stimes for an idempotent Monoid.

When mappend x x = x, this definition should be preferred, because it works in O(1) rather than O(log n)

data SomeException where #

The SomeException type is the root of the exception type hierarchy. When an exception of type e is thrown, behind the scenes it is encapsulated in a SomeException.

Constructors

SomeException :: forall e. Exception e => e -> SomeException

Instances

Show SomeException	Since: base-3.0
Instance details Defined in GHC.Exception.Type Methods showsPrec :: Int -> SomeException -> ShowS # show :: SomeException -> String # showList :: [SomeException] -> ShowS #
Exception SomeException	Since: base-3.0
Instance details Defined in GHC.Exception.Type Methods toException :: SomeException -> SomeException # fromException :: SomeException -> Maybe SomeException # displayException :: SomeException -> String #

(&&) :: Bool -> Bool -> Bool infixr 3 #

Boolean "and"

(||) :: Bool -> Bool -> Bool infixr 2 #

Boolean "or"

not :: Bool -> Bool #

Boolean "not"

data ByteString #

A space-efficient representation of a Word8 vector, supporting many efficient operations.

A ByteString contains 8-bit bytes, or by using the operations from Data.ByteString.Char8 it can be interpreted as containing 8-bit characters.

Instances

Eq ByteString
Instance details Defined in Data.ByteString.Internal Methods (==) :: ByteString -> ByteString -> Bool # (/=) :: ByteString -> ByteString -> Bool #
Data ByteString
Instance details Defined in Data.ByteString.Internal Methods gfoldl :: (forall d b. Data d => c (d -> b) -> d -> c b) -> (forall g. g -> c g) -> ByteString -> c ByteString # gunfold :: (forall b r. Data b => c (b -> r) -> c r) -> (forall r. r -> c r) -> Constr -> c ByteString # toConstr :: ByteString -> Constr # dataTypeOf :: ByteString -> DataType # dataCast1 :: Typeable t => (forall d. Data d => c (t d)) -> Maybe (c ByteString) # dataCast2 :: Typeable t => (forall d e. (Data d, Data e) => c (t d e)) -> Maybe (c ByteString) # gmapT :: (forall b. Data b => b -> b) -> ByteString -> ByteString # gmapQl :: (r -> r' -> r) -> r -> (forall d. Data d => d -> r') -> ByteString -> r # gmapQr :: (r' -> r -> r) -> r -> (forall d. Data d => d -> r') -> ByteString -> r # gmapQ :: (forall d. Data d => d -> u) -> ByteString -> [u] # gmapQi :: Int -> (forall d. Data d => d -> u) -> ByteString -> u # gmapM :: Monad m => (forall d. Data d => d -> m d) -> ByteString -> m ByteString # gmapMp :: MonadPlus m => (forall d. Data d => d -> m d) -> ByteString -> m ByteString # gmapMo :: MonadPlus m => (forall d. Data d => d -> m d) -> ByteString -> m ByteString #
Ord ByteString
Instance details Defined in Data.ByteString.Internal Methods compare :: ByteString -> ByteString -> Ordering # (<) :: ByteString -> ByteString -> Bool # (<=) :: ByteString -> ByteString -> Bool # (>) :: ByteString -> ByteString -> Bool # (>=) :: ByteString -> ByteString -> Bool # max :: ByteString -> ByteString -> ByteString # min :: ByteString -> ByteString -> ByteString #
Read ByteString
Instance details Defined in Data.ByteString.Internal Methods readsPrec :: Int -> ReadS ByteString # readList :: ReadS [ByteString] # readPrec :: ReadPrec ByteString # readListPrec :: ReadPrec [ByteString] #
Show ByteString
Instance details Defined in Data.ByteString.Internal Methods showsPrec :: Int -> ByteString -> ShowS # show :: ByteString -> String # showList :: [ByteString] -> ShowS #
IsString ByteString
Instance details Defined in Data.ByteString.Internal Methods fromString :: String -> ByteString #
Semigroup ByteString
Instance details Defined in Data.ByteString.Internal Methods (<>) :: ByteString -> ByteString -> ByteString # sconcat :: NonEmpty ByteString -> ByteString # stimes :: Integral b => b -> ByteString -> ByteString #
Monoid ByteString
Instance details Defined in Data.ByteString.Internal Methods mempty :: ByteString # mappend :: ByteString -> ByteString -> ByteString # mconcat :: [ByteString] -> ByteString #
NFData ByteString
Instance details Defined in Data.ByteString.Internal Methods rnf :: ByteString -> () #
Hashable ByteString
Instance details Defined in Data.Hashable.Class Methods hashWithSalt :: Int -> ByteString -> Int # hash :: ByteString -> Int #
Print ByteString
Instance details Defined in Universum.Print.Internal Methods hPutStr :: Handle -> ByteString -> IO () # hPutStrLn :: Handle -> ByteString -> IO () #
Container ByteString
Instance details Defined in Universum.Container.Class Associated Types type Element ByteString :: Type # Methods toList :: ByteString -> [Element ByteString] # null :: ByteString -> Bool # foldr :: (Element ByteString -> b -> b) -> b -> ByteString -> b # foldl :: (b -> Element ByteString -> b) -> b -> ByteString -> b # foldl' :: (b -> Element ByteString -> b) -> b -> ByteString -> b # length :: ByteString -> Int # elem :: Element ByteString -> ByteString -> Bool # maximum :: ByteString -> Element ByteString # minimum :: ByteString -> Element ByteString # foldMap :: Monoid m => (Element ByteString -> m) -> ByteString -> m # fold :: ByteString -> Element ByteString # foldr' :: (Element ByteString -> b -> b) -> b -> ByteString -> b # foldr1 :: (Element ByteString -> Element ByteString -> Element ByteString) -> ByteString -> Element ByteString # foldl1 :: (Element ByteString -> Element ByteString -> Element ByteString) -> ByteString -> Element ByteString # notElem :: Element ByteString -> ByteString -> Bool # all :: (Element ByteString -> Bool) -> ByteString -> Bool # any :: (Element ByteString -> Bool) -> ByteString -> Bool # and :: ByteString -> Bool # or :: ByteString -> Bool # find :: (Element ByteString -> Bool) -> ByteString -> Maybe (Element ByteString) # safeHead :: ByteString -> Maybe (Element ByteString) #
One ByteString
Instance details Defined in Universum.Container.Class Associated Types type OneItem ByteString :: Type # Methods one :: OneItem ByteString -> ByteString #
ConvertUtf8 String ByteString
Instance details Defined in Universum.String.Conversion Methods encodeUtf8 :: String -> ByteString # decodeUtf8 :: ByteString -> String # decodeUtf8Strict :: ByteString -> Either UnicodeException String #
ConvertUtf8 Text ByteString
Instance details Defined in Universum.String.Conversion Methods encodeUtf8 :: Text -> ByteString # decodeUtf8 :: ByteString -> Text # decodeUtf8Strict :: ByteString -> Either UnicodeException Text #
ConvertUtf8 Text ByteString
Instance details Defined in Universum.String.Conversion Methods encodeUtf8 :: Text -> ByteString # decodeUtf8 :: ByteString -> Text # decodeUtf8Strict :: ByteString -> Either UnicodeException Text #
type Element ByteString
Instance details Defined in Universum.Container.Class type Element ByteString = Word8
type OneItem ByteString
Instance details Defined in Universum.Container.Class type OneItem ByteString = Word8

data IntMap a #

A map of integers to values a.

Instances

Functor IntMap
Instance details Defined in Data.IntMap.Internal Methods fmap :: (a -> b) -> IntMap a -> IntMap b # (<$) :: a -> IntMap b -> IntMap a #
Foldable IntMap
Instance details Defined in Data.IntMap.Internal Methods fold :: Monoid m => IntMap m -> m # foldMap :: Monoid m => (a -> m) -> IntMap a -> m # foldr :: (a -> b -> b) -> b -> IntMap a -> b # foldr' :: (a -> b -> b) -> b -> IntMap a -> b # foldl :: (b -> a -> b) -> b -> IntMap a -> b # foldl' :: (b -> a -> b) -> b -> IntMap a -> b # foldr1 :: (a -> a -> a) -> IntMap a -> a # foldl1 :: (a -> a -> a) -> IntMap a -> a # toList :: IntMap a -> [a] # null :: IntMap a -> Bool # length :: IntMap a -> Int # elem :: Eq a => a -> IntMap a -> Bool # maximum :: Ord a => IntMap a -> a # minimum :: Ord a => IntMap a -> a # sum :: Num a => IntMap a -> a # product :: Num a => IntMap a -> a #
Traversable IntMap
Instance details Defined in Data.IntMap.Internal Methods traverse :: Applicative f => (a -> f b) -> IntMap a -> f (IntMap b) # sequenceA :: Applicative f => IntMap (f a) -> f (IntMap a) # mapM :: Monad m => (a -> m b) -> IntMap a -> m (IntMap b) # sequence :: Monad m => IntMap (m a) -> m (IntMap a) #
Eq1 IntMap	Since: containers-0.5.9
Instance details Defined in Data.IntMap.Internal Methods liftEq :: (a -> b -> Bool) -> IntMap a -> IntMap b -> Bool #
Ord1 IntMap	Since: containers-0.5.9
Instance details Defined in Data.IntMap.Internal Methods liftCompare :: (a -> b -> Ordering) -> IntMap a -> IntMap b -> Ordering #
Read1 IntMap	Since: containers-0.5.9
Instance details Defined in Data.IntMap.Internal Methods liftReadsPrec :: (Int -> ReadS a) -> ReadS [a] -> Int -> ReadS (IntMap a) # liftReadList :: (Int -> ReadS a) -> ReadS [a] -> ReadS [IntMap a] # liftReadPrec :: ReadPrec a -> ReadPrec [a] -> ReadPrec (IntMap a) # liftReadListPrec :: ReadPrec a -> ReadPrec [a] -> ReadPrec [IntMap a] #
Show1 IntMap	Since: containers-0.5.9
Instance details Defined in Data.IntMap.Internal Methods liftShowsPrec :: (Int -> a -> ShowS) -> ([a] -> ShowS) -> Int -> IntMap a -> ShowS # liftShowList :: (Int -> a -> ShowS) -> ([a] -> ShowS) -> [IntMap a] -> ShowS #
IsList (IntMap a)	Since: containers-0.5.6.2
Instance details Defined in Data.IntMap.Internal Associated Types type Item (IntMap a) :: Type # Methods fromList :: [Item (IntMap a)] -> IntMap a # fromListN :: Int -> [Item (IntMap a)] -> IntMap a # toList :: IntMap a -> [Item (IntMap a)] #
Eq a => Eq (IntMap a)
Instance details Defined in Data.IntMap.Internal Methods (==) :: IntMap a -> IntMap a -> Bool # (/=) :: IntMap a -> IntMap a -> Bool #
Data a => Data (IntMap a)
Instance details Defined in Data.IntMap.Internal Methods gfoldl :: (forall d b. Data d => c (d -> b) -> d -> c b) -> (forall g. g -> c g) -> IntMap a -> c (IntMap a) # gunfold :: (forall b r. Data b => c (b -> r) -> c r) -> (forall r. r -> c r) -> Constr -> c (IntMap a) # toConstr :: IntMap a -> Constr # dataTypeOf :: IntMap a -> DataType # dataCast1 :: Typeable t => (forall d. Data d => c (t d)) -> Maybe (c (IntMap a)) # dataCast2 :: Typeable t => (forall d e. (Data d, Data e) => c (t d e)) -> Maybe (c (IntMap a)) # gmapT :: (forall b. Data b => b -> b) -> IntMap a -> IntMap a # gmapQl :: (r -> r' -> r) -> r -> (forall d. Data d => d -> r') -> IntMap a -> r # gmapQr :: (r' -> r -> r) -> r -> (forall d. Data d => d -> r') -> IntMap a -> r # gmapQ :: (forall d. Data d => d -> u) -> IntMap a -> [u] # gmapQi :: Int -> (forall d. Data d => d -> u) -> IntMap a -> u # gmapM :: Monad m => (forall d. Data d => d -> m d) -> IntMap a -> m (IntMap a) # gmapMp :: MonadPlus m => (forall d. Data d => d -> m d) -> IntMap a -> m (IntMap a) # gmapMo :: MonadPlus m => (forall d. Data d => d -> m d) -> IntMap a -> m (IntMap a) #
Ord a => Ord (IntMap a)
Instance details Defined in Data.IntMap.Internal Methods compare :: IntMap a -> IntMap a -> Ordering # (<) :: IntMap a -> IntMap a -> Bool # (<=) :: IntMap a -> IntMap a -> Bool # (>) :: IntMap a -> IntMap a -> Bool # (>=) :: IntMap a -> IntMap a -> Bool # max :: IntMap a -> IntMap a -> IntMap a # min :: IntMap a -> IntMap a -> IntMap a #
Read e => Read (IntMap e)
Instance details Defined in Data.IntMap.Internal Methods readsPrec :: Int -> ReadS (IntMap e) # readList :: ReadS [IntMap e] # readPrec :: ReadPrec (IntMap e) # readListPrec :: ReadPrec [IntMap e] #
Show a => Show (IntMap a)
Instance details Defined in Data.IntMap.Internal Methods showsPrec :: Int -> IntMap a -> ShowS # show :: IntMap a -> String # showList :: [IntMap a] -> ShowS #
Semigroup (IntMap a)	Since: containers-0.5.7
Instance details Defined in Data.IntMap.Internal Methods (<>) :: IntMap a -> IntMap a -> IntMap a # sconcat :: NonEmpty (IntMap a) -> IntMap a # stimes :: Integral b => b -> IntMap a -> IntMap a #
Monoid (IntMap a)
Instance details Defined in Data.IntMap.Internal Methods mempty :: IntMap a # mappend :: IntMap a -> IntMap a -> IntMap a # mconcat :: [IntMap a] -> IntMap a #
NFData a => NFData (IntMap a)
Instance details Defined in Data.IntMap.Internal Methods rnf :: IntMap a -> () #
ToPairs (IntMap v)
Instance details Defined in Universum.Container.Class Associated Types type Key (IntMap v) :: Type # type Val (IntMap v) :: Type # Methods toPairs :: IntMap v -> [(Key (IntMap v), Val (IntMap v))] # keys :: IntMap v -> [Key (IntMap v)] # elems :: IntMap v -> [Val (IntMap v)] #
Container (IntMap v)
Instance details Defined in Universum.Container.Class Associated Types type Element (IntMap v) :: Type # Methods toList :: IntMap v -> [Element (IntMap v)] # null :: IntMap v -> Bool # foldr :: (Element (IntMap v) -> b -> b) -> b -> IntMap v -> b # foldl :: (b -> Element (IntMap v) -> b) -> b -> IntMap v -> b # foldl' :: (b -> Element (IntMap v) -> b) -> b -> IntMap v -> b # length :: IntMap v -> Int # elem :: Element (IntMap v) -> IntMap v -> Bool # maximum :: IntMap v -> Element (IntMap v) # minimum :: IntMap v -> Element (IntMap v) # foldMap :: Monoid m => (Element (IntMap v) -> m) -> IntMap v -> m # fold :: IntMap v -> Element (IntMap v) # foldr' :: (Element (IntMap v) -> b -> b) -> b -> IntMap v -> b # foldr1 :: (Element (IntMap v) -> Element (IntMap v) -> Element (IntMap v)) -> IntMap v -> Element (IntMap v) # foldl1 :: (Element (IntMap v) -> Element (IntMap v) -> Element (IntMap v)) -> IntMap v -> Element (IntMap v) # notElem :: Element (IntMap v) -> IntMap v -> Bool # all :: (Element (IntMap v) -> Bool) -> IntMap v -> Bool # any :: (Element (IntMap v) -> Bool) -> IntMap v -> Bool # and :: IntMap v -> Bool # or :: IntMap v -> Bool # find :: (Element (IntMap v) -> Bool) -> IntMap v -> Maybe (Element (IntMap v)) # safeHead :: IntMap v -> Maybe (Element (IntMap v)) #
One (IntMap v)
Instance details Defined in Universum.Container.Class Associated Types type OneItem (IntMap v) :: Type # Methods one :: OneItem (IntMap v) -> IntMap v #
type Item (IntMap a)
Instance details Defined in Data.IntMap.Internal type Item (IntMap a) = (Key, a)
type Val (IntMap v)
Instance details Defined in Universum.Container.Class type Val (IntMap v) = v
type Key (IntMap v)
Instance details Defined in Universum.Container.Class type Key (IntMap v) = Int
type Element (IntMap v)
Instance details Defined in Universum.Container.Class type Element (IntMap v) = ElementDefault (IntMap v)
type OneItem (IntMap v)
Instance details Defined in Universum.Container.Class type OneItem (IntMap v) = (Int, v)

data IntSet #

A set of integers.

Instances

IsList IntSet	Since: containers-0.5.6.2
Instance details Defined in Data.IntSet.Internal Associated Types type Item IntSet :: Type # Methods fromList :: [Item IntSet] -> IntSet # fromListN :: Int -> [Item IntSet] -> IntSet # toList :: IntSet -> [Item IntSet] #
Eq IntSet
Instance details Defined in Data.IntSet.Internal Methods (==) :: IntSet -> IntSet -> Bool # (/=) :: IntSet -> IntSet -> Bool #
Data IntSet
Instance details Defined in Data.IntSet.Internal Methods gfoldl :: (forall d b. Data d => c (d -> b) -> d -> c b) -> (forall g. g -> c g) -> IntSet -> c IntSet # gunfold :: (forall b r. Data b => c (b -> r) -> c r) -> (forall r. r -> c r) -> Constr -> c IntSet # toConstr :: IntSet -> Constr # dataTypeOf :: IntSet -> DataType # dataCast1 :: Typeable t => (forall d. Data d => c (t d)) -> Maybe (c IntSet) # dataCast2 :: Typeable t => (forall d e. (Data d, Data e) => c (t d e)) -> Maybe (c IntSet) # gmapT :: (forall b. Data b => b -> b) -> IntSet -> IntSet # gmapQl :: (r -> r' -> r) -> r -> (forall d. Data d => d -> r') -> IntSet -> r # gmapQr :: (r' -> r -> r) -> r -> (forall d. Data d => d -> r') -> IntSet -> r # gmapQ :: (forall d. Data d => d -> u) -> IntSet -> [u] # gmapQi :: Int -> (forall d. Data d => d -> u) -> IntSet -> u # gmapM :: Monad m => (forall d. Data d => d -> m d) -> IntSet -> m IntSet # gmapMp :: MonadPlus m => (forall d. Data d => d -> m d) -> IntSet -> m IntSet # gmapMo :: MonadPlus m => (forall d. Data d => d -> m d) -> IntSet -> m IntSet #
Ord IntSet
Instance details Defined in Data.IntSet.Internal Methods compare :: IntSet -> IntSet -> Ordering # (<) :: IntSet -> IntSet -> Bool # (<=) :: IntSet -> IntSet -> Bool # (>) :: IntSet -> IntSet -> Bool # (>=) :: IntSet -> IntSet -> Bool # max :: IntSet -> IntSet -> IntSet # min :: IntSet -> IntSet -> IntSet #
Read IntSet
Instance details Defined in Data.IntSet.Internal Methods readsPrec :: Int -> ReadS IntSet # readList :: ReadS [IntSet] # readPrec :: ReadPrec IntSet # readListPrec :: ReadPrec [IntSet] #
Show IntSet
Instance details Defined in Data.IntSet.Internal Methods showsPrec :: Int -> IntSet -> ShowS # show :: IntSet -> String # showList :: [IntSet] -> ShowS #
Semigroup IntSet	Since: containers-0.5.7
Instance details Defined in Data.IntSet.Internal Methods (<>) :: IntSet -> IntSet -> IntSet # sconcat :: NonEmpty IntSet -> IntSet # stimes :: Integral b => b -> IntSet -> IntSet #
Monoid IntSet
Instance details Defined in Data.IntSet.Internal Methods mempty :: IntSet # mappend :: IntSet -> IntSet -> IntSet # mconcat :: [IntSet] -> IntSet #
NFData IntSet
Instance details Defined in Data.IntSet.Internal Methods rnf :: IntSet -> () #
Container IntSet
Instance details Defined in Universum.Container.Class Associated Types type Element IntSet :: Type # Methods toList :: IntSet -> [Element IntSet] # null :: IntSet -> Bool # foldr :: (Element IntSet -> b -> b) -> b -> IntSet -> b # foldl :: (b -> Element IntSet -> b) -> b -> IntSet -> b # foldl' :: (b -> Element IntSet -> b) -> b -> IntSet -> b # length :: IntSet -> Int # elem :: Element IntSet -> IntSet -> Bool # maximum :: IntSet -> Element IntSet # minimum :: IntSet -> Element IntSet # foldMap :: Monoid m => (Element IntSet -> m) -> IntSet -> m # fold :: IntSet -> Element IntSet # foldr' :: (Element IntSet -> b -> b) -> b -> IntSet -> b # foldr1 :: (Element IntSet -> Element IntSet -> Element IntSet) -> IntSet -> Element IntSet # foldl1 :: (Element IntSet -> Element IntSet -> Element IntSet) -> IntSet -> Element IntSet # notElem :: Element IntSet -> IntSet -> Bool # all :: (Element IntSet -> Bool) -> IntSet -> Bool # any :: (Element IntSet -> Bool) -> IntSet -> Bool # and :: IntSet -> Bool # or :: IntSet -> Bool # find :: (Element IntSet -> Bool) -> IntSet -> Maybe (Element IntSet) # safeHead :: IntSet -> Maybe (Element IntSet) #
One IntSet
Instance details Defined in Universum.Container.Class Associated Types type OneItem IntSet :: Type # Methods one :: OneItem IntSet -> IntSet #
type Item IntSet
Instance details Defined in Data.IntSet.Internal type Item IntSet = Key
type Element IntSet
Instance details Defined in Universum.Container.Class type Element IntSet = Int
type OneItem IntSet
Instance details Defined in Universum.Container.Class type OneItem IntSet = Int

data Map k a #

A Map from keys k to values a.

Instances

Eq2 Map	Since: containers-0.5.9
Instance details Defined in Data.Map.Internal Methods liftEq2 :: (a -> b -> Bool) -> (c -> d -> Bool) -> Map a c -> Map b d -> Bool #
Ord2 Map	Since: containers-0.5.9
Instance details Defined in Data.Map.Internal Methods liftCompare2 :: (a -> b -> Ordering) -> (c -> d -> Ordering) -> Map a c -> Map b d -> Ordering #
Show2 Map	Since: containers-0.5.9
Instance details Defined in Data.Map.Internal Methods liftShowsPrec2 :: (Int -> a -> ShowS) -> ([a] -> ShowS) -> (Int -> b -> ShowS) -> ([b] -> ShowS) -> Int -> Map a b -> ShowS # liftShowList2 :: (Int -> a -> ShowS) -> ([a] -> ShowS) -> (Int -> b -> ShowS) -> ([b] -> ShowS) -> [Map a b] -> ShowS #
Functor (Map k)
Instance details Defined in Data.Map.Internal Methods fmap :: (a -> b) -> Map k a -> Map k b # (<$) :: a -> Map k b -> Map k a #
Foldable (Map k)
Instance details Defined in Data.Map.Internal Methods fold :: Monoid m => Map k m -> m # foldMap :: Monoid m => (a -> m) -> Map k a -> m # foldr :: (a -> b -> b) -> b -> Map k a -> b # foldr' :: (a -> b -> b) -> b -> Map k a -> b # foldl :: (b -> a -> b) -> b -> Map k a -> b # foldl' :: (b -> a -> b) -> b -> Map k a -> b # foldr1 :: (a -> a -> a) -> Map k a -> a # foldl1 :: (a -> a -> a) -> Map k a -> a # toList :: Map k a -> [a] # null :: Map k a -> Bool # length :: Map k a -> Int # elem :: Eq a => a -> Map k a -> Bool # maximum :: Ord a => Map k a -> a # minimum :: Ord a => Map k a -> a # sum :: Num a => Map k a -> a # product :: Num a => Map k a -> a #
Traversable (Map k)
Instance details Defined in Data.Map.Internal Methods traverse :: Applicative f => (a -> f b) -> Map k a -> f (Map k b) # sequenceA :: Applicative f => Map k (f a) -> f (Map k a) # mapM :: Monad m => (a -> m b) -> Map k a -> m (Map k b) # sequence :: Monad m => Map k (m a) -> m (Map k a) #
Eq k => Eq1 (Map k)	Since: containers-0.5.9
Instance details Defined in Data.Map.Internal Methods liftEq :: (a -> b -> Bool) -> Map k a -> Map k b -> Bool #
Ord k => Ord1 (Map k)	Since: containers-0.5.9
Instance details Defined in Data.Map.Internal Methods liftCompare :: (a -> b -> Ordering) -> Map k a -> Map k b -> Ordering #
(Ord k, Read k) => Read1 (Map k)	Since: containers-0.5.9
Instance details Defined in Data.Map.Internal Methods liftReadsPrec :: (Int -> ReadS a) -> ReadS [a] -> Int -> ReadS (Map k a) # liftReadList :: (Int -> ReadS a) -> ReadS [a] -> ReadS [Map k a] # liftReadPrec :: ReadPrec a -> ReadPrec [a] -> ReadPrec (Map k a) # liftReadListPrec :: ReadPrec a -> ReadPrec [a] -> ReadPrec [Map k a] #
Show k => Show1 (Map k)	Since: containers-0.5.9
Instance details Defined in Data.Map.Internal Methods liftShowsPrec :: (Int -> a -> ShowS) -> ([a] -> ShowS) -> Int -> Map k a -> ShowS # liftShowList :: (Int -> a -> ShowS) -> ([a] -> ShowS) -> [Map k a] -> ShowS #
Ord k => IsList (Map k v)	Since: containers-0.5.6.2
Instance details Defined in Data.Map.Internal Associated Types type Item (Map k v) :: Type # Methods fromList :: [Item (Map k v)] -> Map k v # fromListN :: Int -> [Item (Map k v)] -> Map k v # toList :: Map k v -> [Item (Map k v)] #
(Eq k, Eq a) => Eq (Map k a)
Instance details Defined in Data.Map.Internal Methods (==) :: Map k a -> Map k a -> Bool # (/=) :: Map k a -> Map k a -> Bool #
(Data k, Data a, Ord k) => Data (Map k a)
Instance details Defined in Data.Map.Internal Methods gfoldl :: (forall d b. Data d => c (d -> b) -> d -> c b) -> (forall g. g -> c g) -> Map k a -> c (Map k a) # gunfold :: (forall b r. Data b => c (b -> r) -> c r) -> (forall r. r -> c r) -> Constr -> c (Map k a) # toConstr :: Map k a -> Constr # dataTypeOf :: Map k a -> DataType # dataCast1 :: Typeable t => (forall d. Data d => c (t d)) -> Maybe (c (Map k a)) # dataCast2 :: Typeable t => (forall d e. (Data d, Data e) => c (t d e)) -> Maybe (c (Map k a)) # gmapT :: (forall b. Data b => b -> b) -> Map k a -> Map k a # gmapQl :: (r -> r' -> r) -> r -> (forall d. Data d => d -> r') -> Map k a -> r # gmapQr :: (r' -> r -> r) -> r -> (forall d. Data d => d -> r') -> Map k a -> r # gmapQ :: (forall d. Data d => d -> u) -> Map k a -> [u] # gmapQi :: Int -> (forall d. Data d => d -> u) -> Map k a -> u # gmapM :: Monad m => (forall d. Data d => d -> m d) -> Map k a -> m (Map k a) # gmapMp :: MonadPlus m => (forall d. Data d => d -> m d) -> Map k a -> m (Map k a) # gmapMo :: MonadPlus m => (forall d. Data d => d -> m d) -> Map k a -> m (Map k a) #
(Ord k, Ord v) => Ord (Map k v)
Instance details Defined in Data.Map.Internal Methods compare :: Map k v -> Map k v -> Ordering # (<) :: Map k v -> Map k v -> Bool # (<=) :: Map k v -> Map k v -> Bool # (>) :: Map k v -> Map k v -> Bool # (>=) :: Map k v -> Map k v -> Bool # max :: Map k v -> Map k v -> Map k v # min :: Map k v -> Map k v -> Map k v #
(Ord k, Read k, Read e) => Read (Map k e)
Instance details Defined in Data.Map.Internal Methods readsPrec :: Int -> ReadS (Map k e) # readList :: ReadS [Map k e] # readPrec :: ReadPrec (Map k e) # readListPrec :: ReadPrec [Map k e] #
(Show k, Show a) => Show (Map k a)
Instance details Defined in Data.Map.Internal Methods showsPrec :: Int -> Map k a -> ShowS # show :: Map k a -> String # showList :: [Map k a] -> ShowS #
Ord k => Semigroup (Map k v)
Instance details Defined in Data.Map.Internal Methods (<>) :: Map k v -> Map k v -> Map k v # sconcat :: NonEmpty (Map k v) -> Map k v # stimes :: Integral b => b -> Map k v -> Map k v #
Ord k => Monoid (Map k v)
Instance details Defined in Data.Map.Internal Methods mempty :: Map k v # mappend :: Map k v -> Map k v -> Map k v # mconcat :: [Map k v] -> Map k v #
(NFData k, NFData a) => NFData (Map k a)
Instance details Defined in Data.Map.Internal Methods rnf :: Map k a -> () #
ToPairs (Map k v)
Instance details Defined in Universum.Container.Class Associated Types type Key (Map k v) :: Type # type Val (Map k v) :: Type # Methods toPairs :: Map k v -> [(Key (Map k v), Val (Map k v))] # keys :: Map k v -> [Key (Map k v)] # elems :: Map k v -> [Val (Map k v)] #
Container (Map k v)
Instance details Defined in Universum.Container.Class Associated Types type Element (Map k v) :: Type # Methods toList :: Map k v -> [Element (Map k v)] # null :: Map k v -> Bool # foldr :: (Element (Map k v) -> b -> b) -> b -> Map k v -> b # foldl :: (b -> Element (Map k v) -> b) -> b -> Map k v -> b # foldl' :: (b -> Element (Map k v) -> b) -> b -> Map k v -> b # length :: Map k v -> Int # elem :: Element (Map k v) -> Map k v -> Bool # maximum :: Map k v -> Element (Map k v) # minimum :: Map k v -> Element (Map k v) # foldMap :: Monoid m => (Element (Map k v) -> m) -> Map k v -> m # fold :: Map k v -> Element (Map k v) # foldr' :: (Element (Map k v) -> b -> b) -> b -> Map k v -> b # foldr1 :: (Element (Map k v) -> Element (Map k v) -> Element (Map k v)) -> Map k v -> Element (Map k v) # foldl1 :: (Element (Map k v) -> Element (Map k v) -> Element (Map k v)) -> Map k v -> Element (Map k v) # notElem :: Element (Map k v) -> Map k v -> Bool # all :: (Element (Map k v) -> Bool) -> Map k v -> Bool # any :: (Element (Map k v) -> Bool) -> Map k v -> Bool # and :: Map k v -> Bool # or :: Map k v -> Bool # find :: (Element (Map k v) -> Bool) -> Map k v -> Maybe (Element (Map k v)) # safeHead :: Map k v -> Maybe (Element (Map k v)) #
One (Map k v)
Instance details Defined in Universum.Container.Class Associated Types type OneItem (Map k v) :: Type # Methods one :: OneItem (Map k v) -> Map k v #
type Item (Map k v)
Instance details Defined in Data.Map.Internal type Item (Map k v) = (k, v)
type Val (Map k v)
Instance details Defined in Universum.Container.Class type Val (Map k v) = v
type Key (Map k v)
Instance details Defined in Universum.Container.Class type Key (Map k v) = k
type Element (Map k v)
Instance details Defined in Universum.Container.Class type Element (Map k v) = ElementDefault (Map k v)
type OneItem (Map k v)
Instance details Defined in Universum.Container.Class type OneItem (Map k v) = (k, v)

data Seq a #

General-purpose finite sequences.

Instances

Monad Seq
Instance details Defined in Data.Sequence.Internal Methods (>>=) :: Seq a -> (a -> Seq b) -> Seq b # (>>) :: Seq a -> Seq b -> Seq b # return :: a -> Seq a # fail :: String -> Seq a #
Functor Seq
Instance details Defined in Data.Sequence.Internal Methods fmap :: (a -> b) -> Seq a -> Seq b # (<$) :: a -> Seq b -> Seq a #
MonadFix Seq	Since: containers-0.5.11
Instance details Defined in Data.Sequence.Internal Methods mfix :: (a -> Seq a) -> Seq a #
Applicative Seq	Since: containers-0.5.4
Instance details Defined in Data.Sequence.Internal Methods pure :: a -> Seq a # (<>) :: Seq (a -> b) -> Seq a -> Seq b # liftA2 :: (a -> b -> c) -> Seq a -> Seq b -> Seq c # (>) :: Seq a -> Seq b -> Seq b # (<*) :: Seq a -> Seq b -> Seq a #
Foldable Seq
Instance details Defined in Data.Sequence.Internal Methods fold :: Monoid m => Seq m -> m # foldMap :: Monoid m => (a -> m) -> Seq a -> m # foldr :: (a -> b -> b) -> b -> Seq a -> b # foldr' :: (a -> b -> b) -> b -> Seq a -> b # foldl :: (b -> a -> b) -> b -> Seq a -> b # foldl' :: (b -> a -> b) -> b -> Seq a -> b # foldr1 :: (a -> a -> a) -> Seq a -> a # foldl1 :: (a -> a -> a) -> Seq a -> a # toList :: Seq a -> [a] # null :: Seq a -> Bool # length :: Seq a -> Int # elem :: Eq a => a -> Seq a -> Bool # maximum :: Ord a => Seq a -> a # minimum :: Ord a => Seq a -> a # sum :: Num a => Seq a -> a # product :: Num a => Seq a -> a #
Traversable Seq
Instance details Defined in Data.Sequence.Internal Methods traverse :: Applicative f => (a -> f b) -> Seq a -> f (Seq b) # sequenceA :: Applicative f => Seq (f a) -> f (Seq a) # mapM :: Monad m => (a -> m b) -> Seq a -> m (Seq b) # sequence :: Monad m => Seq (m a) -> m (Seq a) #
Eq1 Seq	Since: containers-0.5.9
Instance details Defined in Data.Sequence.Internal Methods liftEq :: (a -> b -> Bool) -> Seq a -> Seq b -> Bool #
Ord1 Seq	Since: containers-0.5.9
Instance details Defined in Data.Sequence.Internal Methods liftCompare :: (a -> b -> Ordering) -> Seq a -> Seq b -> Ordering #
Read1 Seq	Since: containers-0.5.9
Instance details Defined in Data.Sequence.Internal Methods liftReadsPrec :: (Int -> ReadS a) -> ReadS [a] -> Int -> ReadS (Seq a) # liftReadList :: (Int -> ReadS a) -> ReadS [a] -> ReadS [Seq a] # liftReadPrec :: ReadPrec a -> ReadPrec [a] -> ReadPrec (Seq a) # liftReadListPrec :: ReadPrec a -> ReadPrec [a] -> ReadPrec [Seq a] #
Show1 Seq	Since: containers-0.5.9
Instance details Defined in Data.Sequence.Internal Methods liftShowsPrec :: (Int -> a -> ShowS) -> ([a] -> ShowS) -> Int -> Seq a -> ShowS # liftShowList :: (Int -> a -> ShowS) -> ([a] -> ShowS) -> [Seq a] -> ShowS #
MonadZip Seq	`mzipWith` = `zipWith` `munzip` = `unzip`
Instance details Defined in Data.Sequence.Internal Methods mzip :: Seq a -> Seq b -> Seq (a, b) # mzipWith :: (a -> b -> c) -> Seq a -> Seq b -> Seq c # munzip :: Seq (a, b) -> (Seq a, Seq b) #
Alternative Seq	Since: containers-0.5.4
Instance details Defined in Data.Sequence.Internal Methods empty :: Seq a # (<\|>) :: Seq a -> Seq a -> Seq a # some :: Seq a -> Seq [a] # many :: Seq a -> Seq [a] #
MonadPlus Seq
Instance details Defined in Data.Sequence.Internal Methods mzero :: Seq a # mplus :: Seq a -> Seq a -> Seq a #
UnzipWith Seq
Instance details Defined in Data.Sequence.Internal Methods unzipWith' :: (x -> (a, b)) -> Seq x -> (Seq a, Seq b)
IsList (Seq a)
Instance details Defined in Data.Sequence.Internal Associated Types type Item (Seq a) :: Type # Methods fromList :: [Item (Seq a)] -> Seq a # fromListN :: Int -> [Item (Seq a)] -> Seq a # toList :: Seq a -> [Item (Seq a)] #
Eq a => Eq (Seq a)
Instance details Defined in Data.Sequence.Internal Methods (==) :: Seq a -> Seq a -> Bool # (/=) :: Seq a -> Seq a -> Bool #
Data a => Data (Seq a)
Instance details Defined in Data.Sequence.Internal Methods gfoldl :: (forall d b. Data d => c (d -> b) -> d -> c b) -> (forall g. g -> c g) -> Seq a -> c (Seq a) # gunfold :: (forall b r. Data b => c (b -> r) -> c r) -> (forall r. r -> c r) -> Constr -> c (Seq a) # toConstr :: Seq a -> Constr # dataTypeOf :: Seq a -> DataType # dataCast1 :: Typeable t => (forall d. Data d => c (t d)) -> Maybe (c (Seq a)) # dataCast2 :: Typeable t => (forall d e. (Data d, Data e) => c (t d e)) -> Maybe (c (Seq a)) # gmapT :: (forall b. Data b => b -> b) -> Seq a -> Seq a # gmapQl :: (r -> r' -> r) -> r -> (forall d. Data d => d -> r') -> Seq a -> r # gmapQr :: (r' -> r -> r) -> r -> (forall d. Data d => d -> r') -> Seq a -> r # gmapQ :: (forall d. Data d => d -> u) -> Seq a -> [u] # gmapQi :: Int -> (forall d. Data d => d -> u) -> Seq a -> u # gmapM :: Monad m => (forall d. Data d => d -> m d) -> Seq a -> m (Seq a) # gmapMp :: MonadPlus m => (forall d. Data d => d -> m d) -> Seq a -> m (Seq a) # gmapMo :: MonadPlus m => (forall d. Data d => d -> m d) -> Seq a -> m (Seq a) #
Ord a => Ord (Seq a)
Instance details Defined in Data.Sequence.Internal Methods compare :: Seq a -> Seq a -> Ordering # (<) :: Seq a -> Seq a -> Bool # (<=) :: Seq a -> Seq a -> Bool # (>) :: Seq a -> Seq a -> Bool # (>=) :: Seq a -> Seq a -> Bool # max :: Seq a -> Seq a -> Seq a # min :: Seq a -> Seq a -> Seq a #
Read a => Read (Seq a)
Instance details Defined in Data.Sequence.Internal Methods readsPrec :: Int -> ReadS (Seq a) # readList :: ReadS [Seq a] # readPrec :: ReadPrec (Seq a) # readListPrec :: ReadPrec [Seq a] #
Show a => Show (Seq a)
Instance details Defined in Data.Sequence.Internal Methods showsPrec :: Int -> Seq a -> ShowS # show :: Seq a -> String # showList :: [Seq a] -> ShowS #
a ~ Char => IsString (Seq a)	Since: containers-0.5.7
Instance details Defined in Data.Sequence.Internal Methods fromString :: String -> Seq a #
Semigroup (Seq a)	Since: containers-0.5.7
Instance details Defined in Data.Sequence.Internal Methods (<>) :: Seq a -> Seq a -> Seq a # sconcat :: NonEmpty (Seq a) -> Seq a # stimes :: Integral b => b -> Seq a -> Seq a #
Monoid (Seq a)
Instance details Defined in Data.Sequence.Internal Methods mempty :: Seq a # mappend :: Seq a -> Seq a -> Seq a # mconcat :: [Seq a] -> Seq a #
NFData a => NFData (Seq a)
Instance details Defined in Data.Sequence.Internal Methods rnf :: Seq a -> () #
Container (Seq a)
Instance details Defined in Universum.Container.Class Associated Types type Element (Seq a) :: Type # Methods toList :: Seq a -> [Element (Seq a)] # null :: Seq a -> Bool # foldr :: (Element (Seq a) -> b -> b) -> b -> Seq a -> b # foldl :: (b -> Element (Seq a) -> b) -> b -> Seq a -> b # foldl' :: (b -> Element (Seq a) -> b) -> b -> Seq a -> b # length :: Seq a -> Int # elem :: Element (Seq a) -> Seq a -> Bool # maximum :: Seq a -> Element (Seq a) # minimum :: Seq a -> Element (Seq a) # foldMap :: Monoid m => (Element (Seq a) -> m) -> Seq a -> m # fold :: Seq a -> Element (Seq a) # foldr' :: (Element (Seq a) -> b -> b) -> b -> Seq a -> b # foldr1 :: (Element (Seq a) -> Element (Seq a) -> Element (Seq a)) -> Seq a -> Element (Seq a) # foldl1 :: (Element (Seq a) -> Element (Seq a) -> Element (Seq a)) -> Seq a -> Element (Seq a) # notElem :: Element (Seq a) -> Seq a -> Bool # all :: (Element (Seq a) -> Bool) -> Seq a -> Bool # any :: (Element (Seq a) -> Bool) -> Seq a -> Bool # and :: Seq a -> Bool # or :: Seq a -> Bool # find :: (Element (Seq a) -> Bool) -> Seq a -> Maybe (Element (Seq a)) # safeHead :: Seq a -> Maybe (Element (Seq a)) #
One (Seq a)
Instance details Defined in Universum.Container.Class Associated Types type OneItem (Seq a) :: Type # Methods one :: OneItem (Seq a) -> Seq a #
type Item (Seq a)
Instance details Defined in Data.Sequence.Internal type Item (Seq a) = a
type Element (Seq a)
Instance details Defined in Universum.Container.Class type Element (Seq a) = ElementDefault (Seq a)
type OneItem (Seq a)
Instance details Defined in Universum.Container.Class type OneItem (Seq a) = a

data Set a #

A set of values a.

Instances

Foldable Set
Instance details Defined in Data.Set.Internal Methods fold :: Monoid m => Set m -> m # foldMap :: Monoid m => (a -> m) -> Set a -> m # foldr :: (a -> b -> b) -> b -> Set a -> b # foldr' :: (a -> b -> b) -> b -> Set a -> b # foldl :: (b -> a -> b) -> b -> Set a -> b # foldl' :: (b -> a -> b) -> b -> Set a -> b # foldr1 :: (a -> a -> a) -> Set a -> a # foldl1 :: (a -> a -> a) -> Set a -> a # toList :: Set a -> [a] # null :: Set a -> Bool # length :: Set a -> Int # elem :: Eq a => a -> Set a -> Bool # maximum :: Ord a => Set a -> a # minimum :: Ord a => Set a -> a # sum :: Num a => Set a -> a # product :: Num a => Set a -> a #
Eq1 Set	Since: containers-0.5.9
Instance details Defined in Data.Set.Internal Methods liftEq :: (a -> b -> Bool) -> Set a -> Set b -> Bool #
Ord1 Set	Since: containers-0.5.9
Instance details Defined in Data.Set.Internal Methods liftCompare :: (a -> b -> Ordering) -> Set a -> Set b -> Ordering #
Show1 Set	Since: containers-0.5.9
Instance details Defined in Data.Set.Internal Methods liftShowsPrec :: (Int -> a -> ShowS) -> ([a] -> ShowS) -> Int -> Set a -> ShowS # liftShowList :: (Int -> a -> ShowS) -> ([a] -> ShowS) -> [Set a] -> ShowS #
Ord a => IsList (Set a)	Since: containers-0.5.6.2
Instance details Defined in Data.Set.Internal Associated Types type Item (Set a) :: Type # Methods fromList :: [Item (Set a)] -> Set a # fromListN :: Int -> [Item (Set a)] -> Set a # toList :: Set a -> [Item (Set a)] #
Eq a => Eq (Set a)
Instance details Defined in Data.Set.Internal Methods (==) :: Set a -> Set a -> Bool # (/=) :: Set a -> Set a -> Bool #
(Data a, Ord a) => Data (Set a)
Instance details Defined in Data.Set.Internal Methods gfoldl :: (forall d b. Data d => c (d -> b) -> d -> c b) -> (forall g. g -> c g) -> Set a -> c (Set a) # gunfold :: (forall b r. Data b => c (b -> r) -> c r) -> (forall r. r -> c r) -> Constr -> c (Set a) # toConstr :: Set a -> Constr # dataTypeOf :: Set a -> DataType # dataCast1 :: Typeable t => (forall d. Data d => c (t d)) -> Maybe (c (Set a)) # dataCast2 :: Typeable t => (forall d e. (Data d, Data e) => c (t d e)) -> Maybe (c (Set a)) # gmapT :: (forall b. Data b => b -> b) -> Set a -> Set a # gmapQl :: (r -> r' -> r) -> r -> (forall d. Data d => d -> r') -> Set a -> r # gmapQr :: (r' -> r -> r) -> r -> (forall d. Data d => d -> r') -> Set a -> r # gmapQ :: (forall d. Data d => d -> u) -> Set a -> [u] # gmapQi :: Int -> (forall d. Data d => d -> u) -> Set a -> u # gmapM :: Monad m => (forall d. Data d => d -> m d) -> Set a -> m (Set a) # gmapMp :: MonadPlus m => (forall d. Data d => d -> m d) -> Set a -> m (Set a) # gmapMo :: MonadPlus m => (forall d. Data d => d -> m d) -> Set a -> m (Set a) #
Ord a => Ord (Set a)
Instance details Defined in Data.Set.Internal Methods compare :: Set a -> Set a -> Ordering # (<) :: Set a -> Set a -> Bool # (<=) :: Set a -> Set a -> Bool # (>) :: Set a -> Set a -> Bool # (>=) :: Set a -> Set a -> Bool # max :: Set a -> Set a -> Set a # min :: Set a -> Set a -> Set a #
(Read a, Ord a) => Read (Set a)
Instance details Defined in Data.Set.Internal Methods readsPrec :: Int -> ReadS (Set a) # readList :: ReadS [Set a] # readPrec :: ReadPrec (Set a) # readListPrec :: ReadPrec [Set a] #
Show a => Show (Set a)
Instance details Defined in Data.Set.Internal Methods showsPrec :: Int -> Set a -> ShowS # show :: Set a -> String # showList :: [Set a] -> ShowS #
Ord a => Semigroup (Set a)	Since: containers-0.5.7
Instance details Defined in Data.Set.Internal Methods (<>) :: Set a -> Set a -> Set a # sconcat :: NonEmpty (Set a) -> Set a # stimes :: Integral b => b -> Set a -> Set a #
Ord a => Monoid (Set a)
Instance details Defined in Data.Set.Internal Methods mempty :: Set a # mappend :: Set a -> Set a -> Set a # mconcat :: [Set a] -> Set a #
NFData a => NFData (Set a)
Instance details Defined in Data.Set.Internal Methods rnf :: Set a -> () #
Ord v => Container (Set v)
Instance details Defined in Universum.Container.Class Associated Types type Element (Set v) :: Type # Methods toList :: Set v -> [Element (Set v)] # null :: Set v -> Bool # foldr :: (Element (Set v) -> b -> b) -> b -> Set v -> b # foldl :: (b -> Element (Set v) -> b) -> b -> Set v -> b # foldl' :: (b -> Element (Set v) -> b) -> b -> Set v -> b # length :: Set v -> Int # elem :: Element (Set v) -> Set v -> Bool # maximum :: Set v -> Element (Set v) # minimum :: Set v -> Element (Set v) # foldMap :: Monoid m => (Element (Set v) -> m) -> Set v -> m # fold :: Set v -> Element (Set v) # foldr' :: (Element (Set v) -> b -> b) -> b -> Set v -> b # foldr1 :: (Element (Set v) -> Element (Set v) -> Element (Set v)) -> Set v -> Element (Set v) # foldl1 :: (Element (Set v) -> Element (Set v) -> Element (Set v)) -> Set v -> Element (Set v) # notElem :: Element (Set v) -> Set v -> Bool # all :: (Element (Set v) -> Bool) -> Set v -> Bool # any :: (Element (Set v) -> Bool) -> Set v -> Bool # and :: Set v -> Bool # or :: Set v -> Bool # find :: (Element (Set v) -> Bool) -> Set v -> Maybe (Element (Set v)) # safeHead :: Set v -> Maybe (Element (Set v)) #
One (Set v)
Instance details Defined in Universum.Container.Class Associated Types type OneItem (Set v) :: Type # Methods one :: OneItem (Set v) -> Set v #
type Item (Set a)
Instance details Defined in Data.Set.Internal type Item (Set a) = a
type Element (Set v)
Instance details Defined in Universum.Container.Class type Element (Set v) = ElementDefault (Set v)
type OneItem (Set v)
Instance details Defined in Universum.Container.Class type OneItem (Set v) = v

force :: NFData a => a -> a #

a variant of deepseq that is useful in some circumstances:

force x = x `deepseq` x

force x fully evaluates x, and then returns it. Note that force x only performs evaluation when the value of force x itself is demanded, so essentially it turns shallow evaluation into deep evaluation.

force can be conveniently used in combination with ViewPatterns:

{-# LANGUAGE BangPatterns, ViewPatterns #-}
import Control.DeepSeq

someFun :: ComplexData -> SomeResult
someFun (force -> !arg) = {- 'arg' will be fully evaluated -}

Another useful application is to combine force with evaluate in order to force deep evaluation relative to other IO operations:

import Control.Exception (evaluate)
import Control.DeepSeq

main = do
  result <- evaluate $ force $ pureComputation
  {- 'result' will be fully evaluated at this point -}
  return ()

Finally, here's an exception safe variant of the readFile' example:

readFile' :: FilePath -> IO String
readFile' fn = bracket (openFile fn ReadMode) hClose $ \h ->
                       evaluate . force =<< hGetContents h

Since: deepseq-1.2.0.0

($!!) :: NFData a => (a -> b) -> a -> b infixr 0 #

the deep analogue of $!. In the expression f $!! x, x is fully evaluated before the function f is applied to it.

Since: deepseq-1.2.0.0

deepseq :: NFData a => a -> b -> b #

deepseq: fully evaluates the first argument, before returning the second.

The name deepseq is used to illustrate the relationship to seq: where seq is shallow in the sense that it only evaluates the top level of its argument, deepseq traverses the entire data structure evaluating it completely.

deepseq can be useful for forcing pending exceptions, eradicating space leaks, or forcing lazy I/O to happen. It is also useful in conjunction with parallel Strategies (see the parallel package).

There is no guarantee about the ordering of evaluation. The implementation may evaluate the components of the structure in any order or in parallel. To impose an actual order on evaluation, use pseq from Control.Parallel in the parallel package.

Since: deepseq-1.1.0.0

class NFData a where #

A class of types that can be fully evaluated.

Since: deepseq-1.1.0.0

Minimal complete definition

Nothing

Methods

rnf :: a -> () #

rnf should reduce its argument to normal form (that is, fully evaluate all sub-components), and then return '()'.

`Generic` `NFData` deriving

Starting with GHC 7.2, you can automatically derive instances for types possessing a Generic instance.

Note: Generic1 can be auto-derived starting with GHC 7.4

{-# LANGUAGE DeriveGeneric #-}

import GHC.Generics (Generic, Generic1)
import Control.DeepSeq

data Foo a = Foo a String
             deriving (Eq, Generic, Generic1)

instance NFData a => NFData (Foo a)
instance NFData1 Foo

data Colour = Red | Green | Blue
              deriving Generic

instance NFData Colour

Starting with GHC 7.10, the example above can be written more concisely by enabling the new DeriveAnyClass extension:

{-# LANGUAGE DeriveGeneric, DeriveAnyClass #-}

import GHC.Generics (Generic)
import Control.DeepSeq

data Foo a = Foo a String
             deriving (Eq, Generic, Generic1, NFData, NFData1)

data Colour = Red | Green | Blue
              deriving (Generic, NFData)

Compatibility with previous `deepseq` versions

Prior to version 1.4.0.0, the default implementation of the rnf method was defined as

rnf a = seq a ()

However, starting with deepseq-1.4.0.0, the default implementation is based on DefaultSignatures allowing for more accurate auto-derived NFData instances. If you need the previously used exact default rnf method implementation semantics, use

instance NFData Colour where rnf x = seq x ()

or alternatively

instance NFData Colour where rnf = rwhnf

or

{-# LANGUAGE BangPatterns #-}
instance NFData Colour where rnf !_ = ()

Instances

NFData Bool
Instance details Defined in Control.DeepSeq Methods rnf :: Bool -> () #
NFData Char
Instance details Defined in Control.DeepSeq Methods rnf :: Char -> () #
NFData Double
Instance details Defined in Control.DeepSeq Methods rnf :: Double -> () #
NFData Float
Instance details Defined in Control.DeepSeq Methods rnf :: Float -> () #
NFData Int
Instance details Defined in Control.DeepSeq Methods rnf :: Int -> () #
NFData Int8
Instance details Defined in Control.DeepSeq Methods rnf :: Int8 -> () #
NFData Int16
Instance details Defined in Control.DeepSeq Methods rnf :: Int16 -> () #
NFData Int32
Instance details Defined in Control.DeepSeq Methods rnf :: Int32 -> () #
NFData Int64
Instance details Defined in Control.DeepSeq Methods rnf :: Int64 -> () #
NFData Integer
Instance details Defined in Control.DeepSeq Methods rnf :: Integer -> () #
NFData Natural	Since: deepseq-1.4.0.0
Instance details Defined in Control.DeepSeq Methods rnf :: Natural -> () #
NFData Ordering
Instance details Defined in Control.DeepSeq Methods rnf :: Ordering -> () #
NFData Word
Instance details Defined in Control.DeepSeq Methods rnf :: Word -> () #
NFData Word8
Instance details Defined in Control.DeepSeq Methods rnf :: Word8 -> () #
NFData Word16
Instance details Defined in Control.DeepSeq Methods rnf :: Word16 -> () #
NFData Word32
Instance details Defined in Control.DeepSeq Methods rnf :: Word32 -> () #
NFData Word64
Instance details Defined in Control.DeepSeq Methods rnf :: Word64 -> () #
NFData CallStack	Since: deepseq-1.4.2.0
Instance details Defined in Control.DeepSeq Methods rnf :: CallStack -> () #
NFData ()
Instance details Defined in Control.DeepSeq Methods rnf :: () -> () #
NFData TyCon	NOTE: Prior to `deepseq-1.4.4.0` this instance was only defined for `base-4.8.0.0` and later. Since: deepseq-1.4.0.0
Instance details Defined in Control.DeepSeq Methods rnf :: TyCon -> () #
NFData Void	Defined as `rnf = absurd`. Since: deepseq-1.4.0.0
Instance details Defined in Control.DeepSeq Methods rnf :: Void -> () #
NFData Unique	Since: deepseq-1.4.0.0
Instance details Defined in Control.DeepSeq Methods rnf :: Unique -> () #
NFData Version	Since: deepseq-1.3.0.0
Instance details Defined in Control.DeepSeq Methods rnf :: Version -> () #
NFData ThreadId	Since: deepseq-1.4.0.0
Instance details Defined in Control.DeepSeq Methods rnf :: ThreadId -> () #
NFData ExitCode	Since: deepseq-1.4.2.0
Instance details Defined in Control.DeepSeq Methods rnf :: ExitCode -> () #
NFData MaskingState	Since: deepseq-1.4.4.0
Instance details Defined in Control.DeepSeq Methods rnf :: MaskingState -> () #
NFData TypeRep	NOTE: Prior to `deepseq-1.4.4.0` this instance was only defined for `base-4.8.0.0` and later. Since: deepseq-1.4.0.0
Instance details Defined in Control.DeepSeq Methods rnf :: TypeRep -> () #
NFData All	Since: deepseq-1.4.0.0
Instance details Defined in Control.DeepSeq Methods rnf :: All -> () #
NFData Any	Since: deepseq-1.4.0.0
Instance details Defined in Control.DeepSeq Methods rnf :: Any -> () #
NFData CChar	Since: deepseq-1.4.0.0
Instance details Defined in Control.DeepSeq Methods rnf :: CChar -> () #
NFData CSChar	Since: deepseq-1.4.0.0
Instance details Defined in Control.DeepSeq Methods rnf :: CSChar -> () #
NFData CUChar	Since: deepseq-1.4.0.0
Instance details Defined in Control.DeepSeq Methods rnf :: CUChar -> () #
NFData CShort	Since: deepseq-1.4.0.0
Instance details Defined in Control.DeepSeq Methods rnf :: CShort -> () #
NFData CUShort	Since: deepseq-1.4.0.0
Instance details Defined in Control.DeepSeq Methods rnf :: CUShort -> () #
NFData CInt	Since: deepseq-1.4.0.0
Instance details Defined in Control.DeepSeq Methods rnf :: CInt -> () #
NFData CUInt	Since: deepseq-1.4.0.0
Instance details Defined in Control.DeepSeq Methods rnf :: CUInt -> () #
NFData CLong	Since: deepseq-1.4.0.0
Instance details Defined in Control.DeepSeq Methods rnf :: CLong -> () #
NFData CULong	Since: deepseq-1.4.0.0
Instance details Defined in Control.DeepSeq Methods rnf :: CULong -> () #
NFData CLLong	Since: deepseq-1.4.0.0
Instance details Defined in Control.DeepSeq Methods rnf :: CLLong -> () #
NFData CULLong	Since: deepseq-1.4.0.0
Instance details Defined in Control.DeepSeq Methods rnf :: CULLong -> () #
NFData CBool	Since: deepseq-1.4.3.0
Instance details Defined in Control.DeepSeq Methods rnf :: CBool -> () #
NFData CFloat	Since: deepseq-1.4.0.0
Instance details Defined in Control.DeepSeq Methods rnf :: CFloat -> () #
NFData CDouble	Since: deepseq-1.4.0.0
Instance details Defined in Control.DeepSeq Methods rnf :: CDouble -> () #
NFData CPtrdiff	Since: deepseq-1.4.0.0
Instance details Defined in Control.DeepSeq Methods rnf :: CPtrdiff -> () #
NFData CSize	Since: deepseq-1.4.0.0
Instance details Defined in Control.DeepSeq Methods rnf :: CSize -> () #
NFData CWchar	Since: deepseq-1.4.0.0
Instance details Defined in Control.DeepSeq Methods rnf :: CWchar -> () #
NFData CSigAtomic	Since: deepseq-1.4.0.0
Instance details Defined in Control.DeepSeq Methods rnf :: CSigAtomic -> () #
NFData CClock	Since: deepseq-1.4.0.0
Instance details Defined in Control.DeepSeq Methods rnf :: CClock -> () #
NFData CTime	Since: deepseq-1.4.0.0
Instance details Defined in Control.DeepSeq Methods rnf :: CTime -> () #
NFData CUSeconds	Since: deepseq-1.4.0.0
Instance details Defined in Control.DeepSeq Methods rnf :: CUSeconds -> () #
NFData CSUSeconds	Since: deepseq-1.4.0.0
Instance details Defined in Control.DeepSeq Methods rnf :: CSUSeconds -> () #
NFData CFile	Since: deepseq-1.4.0.0
Instance details Defined in Control.DeepSeq Methods rnf :: CFile -> () #
NFData CFpos	Since: deepseq-1.4.0.0
Instance details Defined in Control.DeepSeq Methods rnf :: CFpos -> () #
NFData CJmpBuf	Since: deepseq-1.4.0.0
Instance details Defined in Control.DeepSeq Methods rnf :: CJmpBuf -> () #
NFData CIntPtr	Since: deepseq-1.4.0.0
Instance details Defined in Control.DeepSeq Methods rnf :: CIntPtr -> () #
NFData CUIntPtr	Since: deepseq-1.4.0.0
Instance details Defined in Control.DeepSeq Methods rnf :: CUIntPtr -> () #
NFData CIntMax	Since: deepseq-1.4.0.0
Instance details Defined in Control.DeepSeq Methods rnf :: CIntMax -> () #
NFData CUIntMax	Since: deepseq-1.4.0.0
Instance details Defined in Control.DeepSeq Methods rnf :: CUIntMax -> () #
NFData Fingerprint	Since: deepseq-1.4.0.0
Instance details Defined in Control.DeepSeq Methods rnf :: Fingerprint -> () #
NFData SrcLoc	Since: deepseq-1.4.2.0
Instance details Defined in Control.DeepSeq Methods rnf :: SrcLoc -> () #
NFData ByteString
Instance details Defined in Data.ByteString.Internal Methods rnf :: ByteString -> () #
NFData IntSet
Instance details Defined in Data.IntSet.Internal Methods rnf :: IntSet -> () #
NFData UnicodeException
Instance details Defined in Data.Text.Encoding.Error Methods rnf :: UnicodeException -> () #
NFData a => NFData [a]
Instance details Defined in Control.DeepSeq Methods rnf :: [a] -> () #
NFData a => NFData (Maybe a)
Instance details Defined in Control.DeepSeq Methods rnf :: Maybe a -> () #
NFData a => NFData (Ratio a)
Instance details Defined in Control.DeepSeq Methods rnf :: Ratio a -> () #
NFData (Ptr a)	Since: deepseq-1.4.2.0
Instance details Defined in Control.DeepSeq Methods rnf :: Ptr a -> () #
NFData (FunPtr a)	Since: deepseq-1.4.2.0
Instance details Defined in Control.DeepSeq Methods rnf :: FunPtr a -> () #
NFData a => NFData (Complex a)
Instance details Defined in Control.DeepSeq Methods rnf :: Complex a -> () #
NFData (Fixed a)	Since: deepseq-1.3.0.0
Instance details Defined in Control.DeepSeq Methods rnf :: Fixed a -> () #
NFData a => NFData (Min a)	Since: deepseq-1.4.2.0
Instance details Defined in Control.DeepSeq Methods rnf :: Min a -> () #
NFData a => NFData (Max a)	Since: deepseq-1.4.2.0
Instance details Defined in Control.DeepSeq Methods rnf :: Max a -> () #
NFData a => NFData (First a)	Since: deepseq-1.4.2.0
Instance details Defined in Control.DeepSeq Methods rnf :: First a -> () #
NFData a => NFData (Last a)	Since: deepseq-1.4.2.0
Instance details Defined in Control.DeepSeq Methods rnf :: Last a -> () #
NFData m => NFData (WrappedMonoid m)	Since: deepseq-1.4.2.0
Instance details Defined in Control.DeepSeq Methods rnf :: WrappedMonoid m -> () #
NFData a => NFData (Option a)	Since: deepseq-1.4.2.0
Instance details Defined in Control.DeepSeq Methods rnf :: Option a -> () #
NFData (StableName a)	Since: deepseq-1.4.0.0
Instance details Defined in Control.DeepSeq Methods rnf :: StableName a -> () #
NFData a => NFData (ZipList a)	Since: deepseq-1.4.0.0
Instance details Defined in Control.DeepSeq Methods rnf :: ZipList a -> () #
NFData a => NFData (Identity a)	Since: deepseq-1.4.0.0
Instance details Defined in Control.DeepSeq Methods rnf :: Identity a -> () #
NFData (IORef a)	NOTE: Only strict in the reference and not the referenced value. Since: deepseq-1.4.2.0
Instance details Defined in Control.DeepSeq Methods rnf :: IORef a -> () #
NFData a => NFData (First a)	Since: deepseq-1.4.0.0
Instance details Defined in Control.DeepSeq Methods rnf :: First a -> () #
NFData a => NFData (Last a)	Since: deepseq-1.4.0.0
Instance details Defined in Control.DeepSeq Methods rnf :: Last a -> () #
NFData a => NFData (Dual a)	Since: deepseq-1.4.0.0
Instance details Defined in Control.DeepSeq Methods rnf :: Dual a -> () #
NFData a => NFData (Sum a)	Since: deepseq-1.4.0.0
Instance details Defined in Control.DeepSeq Methods rnf :: Sum a -> () #
NFData a => NFData (Product a)	Since: deepseq-1.4.0.0
Instance details Defined in Control.DeepSeq Methods rnf :: Product a -> () #
NFData a => NFData (Down a)	Since: deepseq-1.4.0.0
Instance details Defined in Control.DeepSeq Methods rnf :: Down a -> () #
NFData (MVar a)	NOTE: Only strict in the reference and not the referenced value. Since: deepseq-1.4.2.0
Instance details Defined in Control.DeepSeq Methods rnf :: MVar a -> () #
NFData a => NFData (NonEmpty a)	Since: deepseq-1.4.2.0
Instance details Defined in Control.DeepSeq Methods rnf :: NonEmpty a -> () #
NFData a => NFData (IntMap a)
Instance details Defined in Data.IntMap.Internal Methods rnf :: IntMap a -> () #
NFData a => NFData (Seq a)
Instance details Defined in Data.Sequence.Internal Methods rnf :: Seq a -> () #
NFData a => NFData (FingerTree a)
Instance details Defined in Data.Sequence.Internal Methods rnf :: FingerTree a -> () #
NFData a => NFData (Digit a)
Instance details Defined in Data.Sequence.Internal Methods rnf :: Digit a -> () #
NFData a => NFData (Node a)
Instance details Defined in Data.Sequence.Internal Methods rnf :: Node a -> () #
NFData a => NFData (Elem a)
Instance details Defined in Data.Sequence.Internal Methods rnf :: Elem a -> () #
NFData a => NFData (Set a)
Instance details Defined in Data.Set.Internal Methods rnf :: Set a -> () #
NFData a => NFData (Hashed a)
Instance details Defined in Data.Hashable.Class Methods rnf :: Hashed a -> () #
NFData a => NFData (Vector a)
Instance details Defined in Data.Vector Methods rnf :: Vector a -> () #
NFData a => NFData (HashSet a)
Instance details Defined in Data.HashSet.Base Methods rnf :: HashSet a -> () #
NFData (a -> b)	This instance is for convenience and consistency with `seq`. This assumes that WHNF is equivalent to NF for functions. Since: deepseq-1.3.0.0
Instance details Defined in Control.DeepSeq Methods rnf :: (a -> b) -> () #
(NFData a, NFData b) => NFData (Either a b)
Instance details Defined in Control.DeepSeq Methods rnf :: Either a b -> () #
(NFData a, NFData b) => NFData (a, b)
Instance details Defined in Control.DeepSeq Methods rnf :: (a, b) -> () #
(NFData a, NFData b) => NFData (Array a b)
Instance details Defined in Control.DeepSeq Methods rnf :: Array a b -> () #
(NFData a, NFData b) => NFData (Arg a b)	Since: deepseq-1.4.2.0
Instance details Defined in Control.DeepSeq Methods rnf :: Arg a b -> () #
NFData (Proxy a)	Since: deepseq-1.4.0.0
Instance details Defined in Control.DeepSeq Methods rnf :: Proxy a -> () #
NFData (STRef s a)	NOTE: Only strict in the reference and not the referenced value. Since: deepseq-1.4.2.0
Instance details Defined in Control.DeepSeq Methods rnf :: STRef s a -> () #
(NFData k, NFData a) => NFData (Map k a)
Instance details Defined in Data.Map.Internal Methods rnf :: Map k a -> () #
(NFData k, NFData v) => NFData (HashMap k v)
Instance details Defined in Data.HashMap.Base Methods rnf :: HashMap k v -> () #
(NFData k, NFData v) => NFData (Leaf k v)
Instance details Defined in Data.HashMap.Base Methods rnf :: Leaf k v -> () #
(NFData a1, NFData a2, NFData a3) => NFData (a1, a2, a3)
Instance details Defined in Control.DeepSeq Methods rnf :: (a1, a2, a3) -> () #
NFData a => NFData (Const a b)	Since: deepseq-1.4.0.0
Instance details Defined in Control.DeepSeq Methods rnf :: Const a b -> () #
NFData (a :~: b)	Since: deepseq-1.4.3.0
Instance details Defined in Control.DeepSeq Methods rnf :: (a :~: b) -> () #
(NFData a1, NFData a2, NFData a3, NFData a4) => NFData (a1, a2, a3, a4)
Instance details Defined in Control.DeepSeq Methods rnf :: (a1, a2, a3, a4) -> () #
(NFData1 f, NFData1 g, NFData a) => NFData (Product f g a)	Since: deepseq-1.4.3.0
Instance details Defined in Control.DeepSeq Methods rnf :: Product f g a -> () #
(NFData1 f, NFData1 g, NFData a) => NFData (Sum f g a)	Since: deepseq-1.4.3.0
Instance details Defined in Control.DeepSeq Methods rnf :: Sum f g a -> () #
NFData (a :~~: b)	Since: deepseq-1.4.3.0
Instance details Defined in Control.DeepSeq Methods rnf :: (a :~~: b) -> () #
(NFData a1, NFData a2, NFData a3, NFData a4, NFData a5) => NFData (a1, a2, a3, a4, a5)
Instance details Defined in Control.DeepSeq Methods rnf :: (a1, a2, a3, a4, a5) -> () #
(NFData1 f, NFData1 g, NFData a) => NFData (Compose f g a)	Since: deepseq-1.4.3.0
Instance details Defined in Control.DeepSeq Methods rnf :: Compose f g a -> () #
(NFData a1, NFData a2, NFData a3, NFData a4, NFData a5, NFData a6) => NFData (a1, a2, a3, a4, a5, a6)
Instance details Defined in Control.DeepSeq Methods rnf :: (a1, a2, a3, a4, a5, a6) -> () #
(NFData a1, NFData a2, NFData a3, NFData a4, NFData a5, NFData a6, NFData a7) => NFData (a1, a2, a3, a4, a5, a6, a7)
Instance details Defined in Control.DeepSeq Methods rnf :: (a1, a2, a3, a4, a5, a6, a7) -> () #
(NFData a1, NFData a2, NFData a3, NFData a4, NFData a5, NFData a6, NFData a7, NFData a8) => NFData (a1, a2, a3, a4, a5, a6, a7, a8)
Instance details Defined in Control.DeepSeq Methods rnf :: (a1, a2, a3, a4, a5, a6, a7, a8) -> () #
(NFData a1, NFData a2, NFData a3, NFData a4, NFData a5, NFData a6, NFData a7, NFData a8, NFData a9) => NFData (a1, a2, a3, a4, a5, a6, a7, a8, a9)
Instance details Defined in Control.DeepSeq Methods rnf :: (a1, a2, a3, a4, a5, a6, a7, a8, a9) -> () #

newtype MaybeT (m :: Type -> Type) a #

The parameterizable maybe monad, obtained by composing an arbitrary monad with the Maybe monad.

Computations are actions that may produce a value or exit.

The return function yields a computation that produces that value, while >>= sequences two subcomputations, exiting if either computation does.

Constructors

MaybeT
Fields runMaybeT :: m (Maybe a)

Instances

MonadTrans MaybeT
Instance details Defined in Control.Monad.Trans.Maybe Methods lift :: Monad m => m a -> MaybeT m a #
MonadReader r m => MonadReader r (MaybeT m)
Instance details Defined in Control.Monad.Reader.Class Methods ask :: MaybeT m r # local :: (r -> r) -> MaybeT m a -> MaybeT m a # reader :: (r -> a) -> MaybeT m a #
MonadState s m => MonadState s (MaybeT m)
Instance details Defined in Control.Monad.State.Class Methods get :: MaybeT m s # put :: s -> MaybeT m () # state :: (s -> (a, s)) -> MaybeT m a #
MonadError e m => MonadError e (MaybeT m)
Instance details Defined in Control.Monad.Error.Class Methods throwError :: e -> MaybeT m a # catchError :: MaybeT m a -> (e -> MaybeT m a) -> MaybeT m a #
Monad m => Monad (MaybeT m)
Instance details Defined in Control.Monad.Trans.Maybe Methods (>>=) :: MaybeT m a -> (a -> MaybeT m b) -> MaybeT m b # (>>) :: MaybeT m a -> MaybeT m b -> MaybeT m b # return :: a -> MaybeT m a # fail :: String -> MaybeT m a #
Functor m => Functor (MaybeT m)
Instance details Defined in Control.Monad.Trans.Maybe Methods fmap :: (a -> b) -> MaybeT m a -> MaybeT m b # (<$) :: a -> MaybeT m b -> MaybeT m a #
MonadFix m => MonadFix (MaybeT m)
Instance details Defined in Control.Monad.Trans.Maybe Methods mfix :: (a -> MaybeT m a) -> MaybeT m a #
Monad m => MonadFail (MaybeT m)
Instance details Defined in Control.Monad.Trans.Maybe Methods fail :: String -> MaybeT m a #
(Functor m, Monad m) => Applicative (MaybeT m)
Instance details Defined in Control.Monad.Trans.Maybe Methods pure :: a -> MaybeT m a # (<>) :: MaybeT m (a -> b) -> MaybeT m a -> MaybeT m b # liftA2 :: (a -> b -> c) -> MaybeT m a -> MaybeT m b -> MaybeT m c # (>) :: MaybeT m a -> MaybeT m b -> MaybeT m b # (<*) :: MaybeT m a -> MaybeT m b -> MaybeT m a #
Foldable f => Foldable (MaybeT f)
Instance details Defined in Control.Monad.Trans.Maybe Methods fold :: Monoid m => MaybeT f m -> m # foldMap :: Monoid m => (a -> m) -> MaybeT f a -> m # foldr :: (a -> b -> b) -> b -> MaybeT f a -> b # foldr' :: (a -> b -> b) -> b -> MaybeT f a -> b # foldl :: (b -> a -> b) -> b -> MaybeT f a -> b # foldl' :: (b -> a -> b) -> b -> MaybeT f a -> b # foldr1 :: (a -> a -> a) -> MaybeT f a -> a # foldl1 :: (a -> a -> a) -> MaybeT f a -> a # toList :: MaybeT f a -> [a] # null :: MaybeT f a -> Bool # length :: MaybeT f a -> Int # elem :: Eq a => a -> MaybeT f a -> Bool # maximum :: Ord a => MaybeT f a -> a # minimum :: Ord a => MaybeT f a -> a # sum :: Num a => MaybeT f a -> a # product :: Num a => MaybeT f a -> a #
Traversable f => Traversable (MaybeT f)
Instance details Defined in Control.Monad.Trans.Maybe Methods traverse :: Applicative f0 => (a -> f0 b) -> MaybeT f a -> f0 (MaybeT f b) # sequenceA :: Applicative f0 => MaybeT f (f0 a) -> f0 (MaybeT f a) # mapM :: Monad m => (a -> m b) -> MaybeT f a -> m (MaybeT f b) # sequence :: Monad m => MaybeT f (m a) -> m (MaybeT f a) #
Contravariant m => Contravariant (MaybeT m)
Instance details Defined in Control.Monad.Trans.Maybe Methods contramap :: (a -> b) -> MaybeT m b -> MaybeT m a # (>$) :: b -> MaybeT m b -> MaybeT m a #
Eq1 m => Eq1 (MaybeT m)
Instance details Defined in Control.Monad.Trans.Maybe Methods liftEq :: (a -> b -> Bool) -> MaybeT m a -> MaybeT m b -> Bool #
Ord1 m => Ord1 (MaybeT m)
Instance details Defined in Control.Monad.Trans.Maybe Methods liftCompare :: (a -> b -> Ordering) -> MaybeT m a -> MaybeT m b -> Ordering #
Read1 m => Read1 (MaybeT m)
Instance details Defined in Control.Monad.Trans.Maybe Methods liftReadsPrec :: (Int -> ReadS a) -> ReadS [a] -> Int -> ReadS (MaybeT m a) # liftReadList :: (Int -> ReadS a) -> ReadS [a] -> ReadS [MaybeT m a] # liftReadPrec :: ReadPrec a -> ReadPrec [a] -> ReadPrec (MaybeT m a) # liftReadListPrec :: ReadPrec a -> ReadPrec [a] -> ReadPrec [MaybeT m a] #
Show1 m => Show1 (MaybeT m)
Instance details Defined in Control.Monad.Trans.Maybe Methods liftShowsPrec :: (Int -> a -> ShowS) -> ([a] -> ShowS) -> Int -> MaybeT m a -> ShowS # liftShowList :: (Int -> a -> ShowS) -> ([a] -> ShowS) -> [MaybeT m a] -> ShowS #
MonadZip m => MonadZip (MaybeT m)
Instance details Defined in Control.Monad.Trans.Maybe Methods mzip :: MaybeT m a -> MaybeT m b -> MaybeT m (a, b) # mzipWith :: (a -> b -> c) -> MaybeT m a -> MaybeT m b -> MaybeT m c # munzip :: MaybeT m (a, b) -> (MaybeT m a, MaybeT m b) #
MonadIO m => MonadIO (MaybeT m)
Instance details Defined in Control.Monad.Trans.Maybe Methods liftIO :: IO a -> MaybeT m a #
(Functor m, Monad m) => Alternative (MaybeT m)
Instance details Defined in Control.Monad.Trans.Maybe Methods empty :: MaybeT m a # (<\|>) :: MaybeT m a -> MaybeT m a -> MaybeT m a # some :: MaybeT m a -> MaybeT m [a] # many :: MaybeT m a -> MaybeT m [a] #
Monad m => MonadPlus (MaybeT m)
Instance details Defined in Control.Monad.Trans.Maybe Methods mzero :: MaybeT m a # mplus :: MaybeT m a -> MaybeT m a -> MaybeT m a #
MonadThrow m => MonadThrow (MaybeT m)	Throws exceptions into the base monad.
Instance details Defined in Control.Monad.Catch Methods throwM :: Exception e => e -> MaybeT m a #
MonadCatch m => MonadCatch (MaybeT m)	Catches exceptions from the base monad.
Instance details Defined in Control.Monad.Catch Methods catch :: Exception e => MaybeT m a -> (e -> MaybeT m a) -> MaybeT m a #
MonadMask m => MonadMask (MaybeT m)	Since: exceptions-0.10.0
Instance details Defined in Control.Monad.Catch Methods mask :: ((forall a. MaybeT m a -> MaybeT m a) -> MaybeT m b) -> MaybeT m b # uninterruptibleMask :: ((forall a. MaybeT m a -> MaybeT m a) -> MaybeT m b) -> MaybeT m b # generalBracket :: MaybeT m a -> (a -> ExitCase b -> MaybeT m c) -> (a -> MaybeT m b) -> MaybeT m (b, c) #
(Eq1 m, Eq a) => Eq (MaybeT m a)
Instance details Defined in Control.Monad.Trans.Maybe Methods (==) :: MaybeT m a -> MaybeT m a -> Bool # (/=) :: MaybeT m a -> MaybeT m a -> Bool #
(Ord1 m, Ord a) => Ord (MaybeT m a)
Instance details Defined in Control.Monad.Trans.Maybe Methods compare :: MaybeT m a -> MaybeT m a -> Ordering # (<) :: MaybeT m a -> MaybeT m a -> Bool # (<=) :: MaybeT m a -> MaybeT m a -> Bool # (>) :: MaybeT m a -> MaybeT m a -> Bool # (>=) :: MaybeT m a -> MaybeT m a -> Bool # max :: MaybeT m a -> MaybeT m a -> MaybeT m a # min :: MaybeT m a -> MaybeT m a -> MaybeT m a #
(Read1 m, Read a) => Read (MaybeT m a)
Instance details Defined in Control.Monad.Trans.Maybe Methods readsPrec :: Int -> ReadS (MaybeT m a) # readList :: ReadS [MaybeT m a] # readPrec :: ReadPrec (MaybeT m a) # readListPrec :: ReadPrec [MaybeT m a] #
(Show1 m, Show a) => Show (MaybeT m a)
Instance details Defined in Control.Monad.Trans.Maybe Methods showsPrec :: Int -> MaybeT m a -> ShowS # show :: MaybeT m a -> String # showList :: [MaybeT m a] -> ShowS #

newtype ExceptT e (m :: Type -> Type) a #

A monad transformer that adds exceptions to other monads.

ExceptT constructs a monad parameterized over two things:

e - The exception type.
m - The inner monad.

The return function yields a computation that produces the given value, while >>= sequences two subcomputations, exiting on the first exception.

Constructors

ExceptT (m (Either e a))

Instances

MonadReader r m => MonadReader r (ExceptT e m)	Since: mtl-2.2
Instance details Defined in Control.Monad.Reader.Class Methods ask :: ExceptT e m r # local :: (r -> r) -> ExceptT e m a -> ExceptT e m a # reader :: (r -> a) -> ExceptT e m a #
MonadState s m => MonadState s (ExceptT e m)	Since: mtl-2.2
Instance details Defined in Control.Monad.State.Class Methods get :: ExceptT e m s # put :: s -> ExceptT e m () # state :: (s -> (a, s)) -> ExceptT e m a #
Monad m => MonadError e (ExceptT e m)	Since: mtl-2.2
Instance details Defined in Control.Monad.Error.Class Methods throwError :: e -> ExceptT e m a # catchError :: ExceptT e m a -> (e -> ExceptT e m a) -> ExceptT e m a #
MonadTrans (ExceptT e)
Instance details Defined in Control.Monad.Trans.Except Methods lift :: Monad m => m a -> ExceptT e m a #
Monad m => Monad (ExceptT e m)
Instance details Defined in Control.Monad.Trans.Except Methods (>>=) :: ExceptT e m a -> (a -> ExceptT e m b) -> ExceptT e m b # (>>) :: ExceptT e m a -> ExceptT e m b -> ExceptT e m b # return :: a -> ExceptT e m a # fail :: String -> ExceptT e m a #
Functor m => Functor (ExceptT e m)
Instance details Defined in Control.Monad.Trans.Except Methods fmap :: (a -> b) -> ExceptT e m a -> ExceptT e m b # (<$) :: a -> ExceptT e m b -> ExceptT e m a #
MonadFix m => MonadFix (ExceptT e m)
Instance details Defined in Control.Monad.Trans.Except Methods mfix :: (a -> ExceptT e m a) -> ExceptT e m a #
MonadFail m => MonadFail (ExceptT e m)
Instance details Defined in Control.Monad.Trans.Except Methods fail :: String -> ExceptT e m a #
(Functor m, Monad m) => Applicative (ExceptT e m)
Instance details Defined in Control.Monad.Trans.Except Methods pure :: a -> ExceptT e m a # (<>) :: ExceptT e m (a -> b) -> ExceptT e m a -> ExceptT e m b # liftA2 :: (a -> b -> c) -> ExceptT e m a -> ExceptT e m b -> ExceptT e m c # (>) :: ExceptT e m a -> ExceptT e m b -> ExceptT e m b # (<*) :: ExceptT e m a -> ExceptT e m b -> ExceptT e m a #
Foldable f => Foldable (ExceptT e f)
Instance details Defined in Control.Monad.Trans.Except Methods fold :: Monoid m => ExceptT e f m -> m # foldMap :: Monoid m => (a -> m) -> ExceptT e f a -> m # foldr :: (a -> b -> b) -> b -> ExceptT e f a -> b # foldr' :: (a -> b -> b) -> b -> ExceptT e f a -> b # foldl :: (b -> a -> b) -> b -> ExceptT e f a -> b # foldl' :: (b -> a -> b) -> b -> ExceptT e f a -> b # foldr1 :: (a -> a -> a) -> ExceptT e f a -> a # foldl1 :: (a -> a -> a) -> ExceptT e f a -> a # toList :: ExceptT e f a -> [a] # null :: ExceptT e f a -> Bool # length :: ExceptT e f a -> Int # elem :: Eq a => a -> ExceptT e f a -> Bool # maximum :: Ord a => ExceptT e f a -> a # minimum :: Ord a => ExceptT e f a -> a # sum :: Num a => ExceptT e f a -> a # product :: Num a => ExceptT e f a -> a #
Traversable f => Traversable (ExceptT e f)
Instance details Defined in Control.Monad.Trans.Except Methods traverse :: Applicative f0 => (a -> f0 b) -> ExceptT e f a -> f0 (ExceptT e f b) # sequenceA :: Applicative f0 => ExceptT e f (f0 a) -> f0 (ExceptT e f a) # mapM :: Monad m => (a -> m b) -> ExceptT e f a -> m (ExceptT e f b) # sequence :: Monad m => ExceptT e f (m a) -> m (ExceptT e f a) #
Contravariant m => Contravariant (ExceptT e m)
Instance details Defined in Control.Monad.Trans.Except Methods contramap :: (a -> b) -> ExceptT e m b -> ExceptT e m a # (>$) :: b -> ExceptT e m b -> ExceptT e m a #
(Eq e, Eq1 m) => Eq1 (ExceptT e m)
Instance details Defined in Control.Monad.Trans.Except Methods liftEq :: (a -> b -> Bool) -> ExceptT e m a -> ExceptT e m b -> Bool #
(Ord e, Ord1 m) => Ord1 (ExceptT e m)
Instance details Defined in Control.Monad.Trans.Except Methods liftCompare :: (a -> b -> Ordering) -> ExceptT e m a -> ExceptT e m b -> Ordering #
(Read e, Read1 m) => Read1 (ExceptT e m)
Instance details Defined in Control.Monad.Trans.Except Methods liftReadsPrec :: (Int -> ReadS a) -> ReadS [a] -> Int -> ReadS (ExceptT e m a) # liftReadList :: (Int -> ReadS a) -> ReadS [a] -> ReadS [ExceptT e m a] # liftReadPrec :: ReadPrec a -> ReadPrec [a] -> ReadPrec (ExceptT e m a) # liftReadListPrec :: ReadPrec a -> ReadPrec [a] -> ReadPrec [ExceptT e m a] #
(Show e, Show1 m) => Show1 (ExceptT e m)
Instance details Defined in Control.Monad.Trans.Except Methods liftShowsPrec :: (Int -> a -> ShowS) -> ([a] -> ShowS) -> Int -> ExceptT e m a -> ShowS # liftShowList :: (Int -> a -> ShowS) -> ([a] -> ShowS) -> [ExceptT e m a] -> ShowS #
MonadZip m => MonadZip (ExceptT e m)
Instance details Defined in Control.Monad.Trans.Except Methods mzip :: ExceptT e m a -> ExceptT e m b -> ExceptT e m (a, b) # mzipWith :: (a -> b -> c) -> ExceptT e m a -> ExceptT e m b -> ExceptT e m c # munzip :: ExceptT e m (a, b) -> (ExceptT e m a, ExceptT e m b) #
MonadIO m => MonadIO (ExceptT e m)
Instance details Defined in Control.Monad.Trans.Except Methods liftIO :: IO a -> ExceptT e m a #
(Functor m, Monad m, Monoid e) => Alternative (ExceptT e m)
Instance details Defined in Control.Monad.Trans.Except Methods empty :: ExceptT e m a # (<\|>) :: ExceptT e m a -> ExceptT e m a -> ExceptT e m a # some :: ExceptT e m a -> ExceptT e m [a] # many :: ExceptT e m a -> ExceptT e m [a] #
(Monad m, Monoid e) => MonadPlus (ExceptT e m)
Instance details Defined in Control.Monad.Trans.Except Methods mzero :: ExceptT e m a # mplus :: ExceptT e m a -> ExceptT e m a -> ExceptT e m a #
MonadThrow m => MonadThrow (ExceptT e m)	Throws exceptions into the base monad.
Instance details Defined in Control.Monad.Catch Methods throwM :: Exception e0 => e0 -> ExceptT e m a #
MonadCatch m => MonadCatch (ExceptT e m)	Catches exceptions from the base monad.
Instance details Defined in Control.Monad.Catch Methods catch :: Exception e0 => ExceptT e m a -> (e0 -> ExceptT e m a) -> ExceptT e m a #
MonadMask m => MonadMask (ExceptT e m)	Since: exceptions-0.9.0
Instance details Defined in Control.Monad.Catch Methods mask :: ((forall a. ExceptT e m a -> ExceptT e m a) -> ExceptT e m b) -> ExceptT e m b # uninterruptibleMask :: ((forall a. ExceptT e m a -> ExceptT e m a) -> ExceptT e m b) -> ExceptT e m b # generalBracket :: ExceptT e m a -> (a -> ExitCase b -> ExceptT e m c) -> (a -> ExceptT e m b) -> ExceptT e m (b, c) #
(Eq e, Eq1 m, Eq a) => Eq (ExceptT e m a)
Instance details Defined in Control.Monad.Trans.Except Methods (==) :: ExceptT e m a -> ExceptT e m a -> Bool # (/=) :: ExceptT e m a -> ExceptT e m a -> Bool #
(Ord e, Ord1 m, Ord a) => Ord (ExceptT e m a)
Instance details Defined in Control.Monad.Trans.Except Methods compare :: ExceptT e m a -> ExceptT e m a -> Ordering # (<) :: ExceptT e m a -> ExceptT e m a -> Bool # (<=) :: ExceptT e m a -> ExceptT e m a -> Bool # (>) :: ExceptT e m a -> ExceptT e m a -> Bool # (>=) :: ExceptT e m a -> ExceptT e m a -> Bool # max :: ExceptT e m a -> ExceptT e m a -> ExceptT e m a # min :: ExceptT e m a -> ExceptT e m a -> ExceptT e m a #
(Read e, Read1 m, Read a) => Read (ExceptT e m a)
Instance details Defined in Control.Monad.Trans.Except Methods readsPrec :: Int -> ReadS (ExceptT e m a) # readList :: ReadS [ExceptT e m a] # readPrec :: ReadPrec (ExceptT e m a) # readListPrec :: ReadPrec [ExceptT e m a] #
(Show e, Show1 m, Show a) => Show (ExceptT e m a)
Instance details Defined in Control.Monad.Trans.Except Methods showsPrec :: Int -> ExceptT e m a -> ShowS # show :: ExceptT e m a -> String # showList :: [ExceptT e m a] -> ShowS #

class Monad m => MonadThrow (m :: Type -> Type) #

A class for monads in which exceptions may be thrown.

Instances should obey the following law:

throwM e >> x = throwM e

In other words, throwing an exception short-circuits the rest of the monadic computation.

Minimal complete definition

throwM

Instances

MonadThrow []
Instance details Defined in Control.Monad.Catch Methods throwM :: Exception e => e -> [a] #
MonadThrow Maybe
Instance details Defined in Control.Monad.Catch Methods throwM :: Exception e => e -> Maybe a #
MonadThrow IO
Instance details Defined in Control.Monad.Catch Methods throwM :: Exception e => e -> IO a #
MonadThrow Q
Instance details Defined in Control.Monad.Catch Methods throwM :: Exception e => e -> Q a #
MonadThrow STM
Instance details Defined in Control.Monad.Catch Methods throwM :: Exception e => e -> STM a #
e ~ SomeException => MonadThrow (Either e)
Instance details Defined in Control.Monad.Catch Methods throwM :: Exception e0 => e0 -> Either e a #
MonadThrow (ST s)
Instance details Defined in Control.Monad.Catch Methods throwM :: Exception e => e -> ST s a #
MonadThrow m => MonadThrow (MaybeT m)	Throws exceptions into the base monad.
Instance details Defined in Control.Monad.Catch Methods throwM :: Exception e => e -> MaybeT m a #
MonadThrow m => MonadThrow (ListT m)
Instance details Defined in Control.Monad.Catch Methods throwM :: Exception e => e -> ListT m a #
MonadThrow m => MonadThrow (ExceptT e m)	Throws exceptions into the base monad.
Instance details Defined in Control.Monad.Catch Methods throwM :: Exception e0 => e0 -> ExceptT e m a #
MonadThrow m => MonadThrow (StateT s m)
Instance details Defined in Control.Monad.Catch Methods throwM :: Exception e => e -> StateT s m a #
MonadThrow m => MonadThrow (IdentityT m)
Instance details Defined in Control.Monad.Catch Methods throwM :: Exception e => e -> IdentityT m a #
(Error e, MonadThrow m) => MonadThrow (ErrorT e m)	Throws exceptions into the base monad.
Instance details Defined in Control.Monad.Catch Methods throwM :: Exception e0 => e0 -> ErrorT e m a #
MonadThrow m => MonadThrow (StateT s m)
Instance details Defined in Control.Monad.Catch Methods throwM :: Exception e => e -> StateT s m a #
(MonadThrow m, Monoid w) => MonadThrow (WriterT w m)
Instance details Defined in Control.Monad.Catch Methods throwM :: Exception e => e -> WriterT w m a #
(MonadThrow m, Monoid w) => MonadThrow (WriterT w m)
Instance details Defined in Control.Monad.Catch Methods throwM :: Exception e => e -> WriterT w m a #
MonadThrow m => MonadThrow (ReaderT r m)
Instance details Defined in Control.Monad.Catch Methods throwM :: Exception e => e -> ReaderT r m a #
MonadThrow m => MonadThrow (ContT r m)
Instance details Defined in Control.Monad.Catch Methods throwM :: Exception e => e -> ContT r m a #
(MonadThrow m, Monoid w) => MonadThrow (RWST r w s m)
Instance details Defined in Control.Monad.Catch Methods throwM :: Exception e => e -> RWST r w s m a #
(MonadThrow m, Monoid w) => MonadThrow (RWST r w s m)
Instance details Defined in Control.Monad.Catch Methods throwM :: Exception e => e -> RWST r w s m a #

class MonadThrow m => MonadCatch (m :: Type -> Type) #

A class for monads which allow exceptions to be caught, in particular exceptions which were thrown by throwM.

Instances should obey the following law:

catch (throwM e) f = f e

Note that the ability to catch an exception does not guarantee that we can deal with all possible exit points from a computation. Some monads, such as continuation-based stacks, allow for more than just a success/failure strategy, and therefore catch cannot be used by those monads to properly implement a function such as finally. For more information, see MonadMask.

Minimal complete definition

catch

Instances

MonadCatch IO
Instance details Defined in Control.Monad.Catch Methods catch :: Exception e => IO a -> (e -> IO a) -> IO a #
MonadCatch STM
Instance details Defined in Control.Monad.Catch Methods catch :: Exception e => STM a -> (e -> STM a) -> STM a #
e ~ SomeException => MonadCatch (Either e)	Since: exceptions-0.8.3
Instance details Defined in Control.Monad.Catch Methods catch :: Exception e0 => Either e a -> (e0 -> Either e a) -> Either e a #
MonadCatch m => MonadCatch (MaybeT m)	Catches exceptions from the base monad.
Instance details Defined in Control.Monad.Catch Methods catch :: Exception e => MaybeT m a -> (e -> MaybeT m a) -> MaybeT m a #
MonadCatch m => MonadCatch (ListT m)
Instance details Defined in Control.Monad.Catch Methods catch :: Exception e => ListT m a -> (e -> ListT m a) -> ListT m a #
MonadCatch m => MonadCatch (ExceptT e m)	Catches exceptions from the base monad.
Instance details Defined in Control.Monad.Catch Methods catch :: Exception e0 => ExceptT e m a -> (e0 -> ExceptT e m a) -> ExceptT e m a #
MonadCatch m => MonadCatch (StateT s m)
Instance details Defined in Control.Monad.Catch Methods catch :: Exception e => StateT s m a -> (e -> StateT s m a) -> StateT s m a #
MonadCatch m => MonadCatch (IdentityT m)
Instance details Defined in Control.Monad.Catch Methods catch :: Exception e => IdentityT m a -> (e -> IdentityT m a) -> IdentityT m a #
(Error e, MonadCatch m) => MonadCatch (ErrorT e m)	Catches exceptions from the base monad.
Instance details Defined in Control.Monad.Catch Methods catch :: Exception e0 => ErrorT e m a -> (e0 -> ErrorT e m a) -> ErrorT e m a #
MonadCatch m => MonadCatch (StateT s m)
Instance details Defined in Control.Monad.Catch Methods catch :: Exception e => StateT s m a -> (e -> StateT s m a) -> StateT s m a #
(MonadCatch m, Monoid w) => MonadCatch (WriterT w m)
Instance details Defined in Control.Monad.Catch Methods catch :: Exception e => WriterT w m a -> (e -> WriterT w m a) -> WriterT w m a #
(MonadCatch m, Monoid w) => MonadCatch (WriterT w m)
Instance details Defined in Control.Monad.Catch Methods catch :: Exception e => WriterT w m a -> (e -> WriterT w m a) -> WriterT w m a #
MonadCatch m => MonadCatch (ReaderT r m)
Instance details Defined in Control.Monad.Catch Methods catch :: Exception e => ReaderT r m a -> (e -> ReaderT r m a) -> ReaderT r m a #
(MonadCatch m, Monoid w) => MonadCatch (RWST r w s m)
Instance details Defined in Control.Monad.Catch Methods catch :: Exception e => RWST r w s m a -> (e -> RWST r w s m a) -> RWST r w s m a #
(MonadCatch m, Monoid w) => MonadCatch (RWST r w s m)
Instance details Defined in Control.Monad.Catch Methods catch :: Exception e => RWST r w s m a -> (e -> RWST r w s m a) -> RWST r w s m a #

class MonadCatch m => MonadMask (m :: Type -> Type) where #

A class for monads which provide for the ability to account for all possible exit points from a computation, and to mask asynchronous exceptions. Continuation-based monads are invalid instances of this class.

Instances should ensure that, in the following code:

fg = f `finally` g

The action g is called regardless of what occurs within f, including async exceptions. Some monads allow f to abort the computation via other effects than throwing an exception. For simplicity, we will consider aborting and throwing an exception to be two forms of "throwing an error".

If f and g both throw an error, the error thrown by fg depends on which errors we're talking about. In a monad transformer stack, the deeper layers override the effects of the inner layers; for example, ExceptT e1 (Except e2) a represents a value of type Either e2 (Either e1 a), so throwing both an e1 and an e2 will result in Left e2. If f and g both throw an error from the same layer, instances should ensure that the error from g wins.

Effects other than throwing an error are also overriden by the deeper layers. For example, StateT s Maybe a represents a value of type s -> Maybe (a, s), so if an error thrown from f causes this function to return Nothing, any changes to the state which f also performed will be erased. As a result, g will see the state as it was before f. Once g completes, f's error will be rethrown, so g' state changes will be erased as well. This is the normal interaction between effects in a monad transformer stack.

By contrast, lifted-base's version of finally always discards all of g's non-IO effects, and g never sees any of f's non-IO effects, regardless of the layer ordering and regardless of whether f throws an error. This is not the result of interacting effects, but a consequence of MonadBaseControl's approach.

Methods

mask :: ((forall a. m a -> m a) -> m b) -> m b #

Runs an action with asynchronous exceptions disabled. The action is provided a method for restoring the async. environment to what it was at the mask call. See Control.Exception's mask.

uninterruptibleMask :: ((forall a. m a -> m a) -> m b) -> m b #

Like mask, but the masked computation is not interruptible (see Control.Exception's uninterruptibleMask. WARNING: Only use if you need to mask exceptions around an interruptible operation AND you can guarantee the interruptible operation will only block for a short period of time. Otherwise you render the program/thread unresponsive and/or unkillable.

generalBracket #

Arguments

:: m a	acquire some resource
-> (a -> ExitCase b -> m c)	release the resource, observing the outcome of the inner action
-> (a -> m b)	inner action to perform with the resource
-> m (b, c)

A generalized version of bracket which uses ExitCase to distinguish the different exit cases, and returns the values of both the use and release actions. In practice, this extra information is rarely needed, so it is often more convenient to use one of the simpler functions which are defined in terms of this one, such as bracket, finally, onError, and bracketOnError.

This function exists because in order to thread their effects through the execution of bracket, monad transformers need values to be threaded from use to release and from release to the output value.

NOTE This method was added in version 0.9.0 of this library. Previously, implementation of functions like bracket and finally in this module were based on the mask and uninterruptibleMask functions only, disallowing some classes of tranformers from having MonadMask instances (notably multi-exit-point transformers like ExceptT). If you are a library author, you'll now need to provide an implementation for this method. The StateT implementation demonstrates most of the subtleties:

generalBracket acquire release use = StateT $ s0 -> do
  ((b, _s2), (c, s3)) <- generalBracket
    (runStateT acquire s0)
    ((resource, s1) exitCase -> case exitCase of
      ExitCaseSuccess (b, s2) -> runStateT (release resource (ExitCaseSuccess b)) s2

      -- In the two other cases, the base monad overrides use's state
      -- changes and the state reverts to s1.
      ExitCaseException e     -> runStateT (release resource (ExitCaseException e)) s1
      ExitCaseAbort           -> runStateT (release resource ExitCaseAbort) s1
    )
    ((resource, s1) -> runStateT (use resource) s1)
  return ((b, c), s3)

The StateT s m implementation of generalBracket delegates to the m implementation of generalBracket. The acquire, use, and release arguments given to StateT's implementation produce actions of type StateT s m a, StateT s m b, and StateT s m c. In order to run those actions in the base monad, we need to call runStateT, from which we obtain actions of type m (a, s), m (b, s), and m (c, s). Since each action produces the next state, it is important to feed the state produced by the previous action to the next action.

In the ExitCaseSuccess case, the state starts at s0, flows through acquire to become s1, flows through use to become s2, and finally flows through release to become s3. In the other two cases, release does not receive the value s2, so its action cannot see the state changes performed by use. This is fine, because in those two cases, an error was thrown in the base monad, so as per the usual interaction between effects in a monad transformer stack, those state changes get reverted. So we start from s1 instead.

Finally, the m implementation of generalBracket returns the pairs (b, s) and (c, s). For monad transformers other than StateT, this will be some other type representing the effects and values performed and returned by the use and release actions. The effect part of the use result, in this case _s2, usually needs to be discarded, since those effects have already been incorporated in the release action.

The only effect which is intentionally not incorporated in the release action is the effect of throwing an error. In that case, the error must be re-thrown. One subtlety which is easy to miss is that in the case in which use and release both throw an error, the error from release should take priority. Here is an implementation for ExceptT which demonstrates how to do this.

generalBracket acquire release use = ExceptT $ do
  (eb, ec) <- generalBracket
    (runExceptT acquire)
    (eresource exitCase -> case eresource of
      Left e -> return (Left e) -- nothing to release, acquire didn't succeed
      Right resource -> case exitCase of
        ExitCaseSuccess (Right b) -> runExceptT (release resource (ExitCaseSuccess b))
        ExitCaseException e       -> runExceptT (release resource (ExitCaseException e))
        _                         -> runExceptT (release resource ExitCaseAbort))
    (either (return . Left) (runExceptT . use))
  return $ do
    -- The order in which we perform those two Either effects determines
    -- which error will win if they are both Lefts. We want the error from
    -- release to win.
    c <- ec
    b <- eb
    return (b, c)

Since: exceptions-0.9.0

Instances

MonadMask IO
Instance details Defined in Control.Monad.Catch Methods mask :: ((forall a. IO a -> IO a) -> IO b) -> IO b # uninterruptibleMask :: ((forall a. IO a -> IO a) -> IO b) -> IO b # generalBracket :: IO a -> (a -> ExitCase b -> IO c) -> (a -> IO b) -> IO (b, c) #
e ~ SomeException => MonadMask (Either e)	Since: exceptions-0.8.3
Instance details Defined in Control.Monad.Catch Methods mask :: ((forall a. Either e a -> Either e a) -> Either e b) -> Either e b # uninterruptibleMask :: ((forall a. Either e a -> Either e a) -> Either e b) -> Either e b # generalBracket :: Either e a -> (a -> ExitCase b -> Either e c) -> (a -> Either e b) -> Either e (b, c) #
MonadMask m => MonadMask (MaybeT m)	Since: exceptions-0.10.0
Instance details Defined in Control.Monad.Catch Methods mask :: ((forall a. MaybeT m a -> MaybeT m a) -> MaybeT m b) -> MaybeT m b # uninterruptibleMask :: ((forall a. MaybeT m a -> MaybeT m a) -> MaybeT m b) -> MaybeT m b # generalBracket :: MaybeT m a -> (a -> ExitCase b -> MaybeT m c) -> (a -> MaybeT m b) -> MaybeT m (b, c) #
MonadMask m => MonadMask (ExceptT e m)	Since: exceptions-0.9.0
Instance details Defined in Control.Monad.Catch Methods mask :: ((forall a. ExceptT e m a -> ExceptT e m a) -> ExceptT e m b) -> ExceptT e m b # uninterruptibleMask :: ((forall a. ExceptT e m a -> ExceptT e m a) -> ExceptT e m b) -> ExceptT e m b # generalBracket :: ExceptT e m a -> (a -> ExitCase b -> ExceptT e m c) -> (a -> ExceptT e m b) -> ExceptT e m (b, c) #
MonadMask m => MonadMask (StateT s m)
Instance details Defined in Control.Monad.Catch Methods mask :: ((forall a. StateT s m a -> StateT s m a) -> StateT s m b) -> StateT s m b # uninterruptibleMask :: ((forall a. StateT s m a -> StateT s m a) -> StateT s m b) -> StateT s m b # generalBracket :: StateT s m a -> (a -> ExitCase b -> StateT s m c) -> (a -> StateT s m b) -> StateT s m (b, c) #
MonadMask m => MonadMask (IdentityT m)
Instance details Defined in Control.Monad.Catch Methods mask :: ((forall a. IdentityT m a -> IdentityT m a) -> IdentityT m b) -> IdentityT m b # uninterruptibleMask :: ((forall a. IdentityT m a -> IdentityT m a) -> IdentityT m b) -> IdentityT m b # generalBracket :: IdentityT m a -> (a -> ExitCase b -> IdentityT m c) -> (a -> IdentityT m b) -> IdentityT m (b, c) #
(Error e, MonadMask m) => MonadMask (ErrorT e m)
Instance details Defined in Control.Monad.Catch Methods mask :: ((forall a. ErrorT e m a -> ErrorT e m a) -> ErrorT e m b) -> ErrorT e m b # uninterruptibleMask :: ((forall a. ErrorT e m a -> ErrorT e m a) -> ErrorT e m b) -> ErrorT e m b # generalBracket :: ErrorT e m a -> (a -> ExitCase b -> ErrorT e m c) -> (a -> ErrorT e m b) -> ErrorT e m (b, c) #
MonadMask m => MonadMask (StateT s m)
Instance details Defined in Control.Monad.Catch Methods mask :: ((forall a. StateT s m a -> StateT s m a) -> StateT s m b) -> StateT s m b # uninterruptibleMask :: ((forall a. StateT s m a -> StateT s m a) -> StateT s m b) -> StateT s m b # generalBracket :: StateT s m a -> (a -> ExitCase b -> StateT s m c) -> (a -> StateT s m b) -> StateT s m (b, c) #
(MonadMask m, Monoid w) => MonadMask (WriterT w m)
Instance details Defined in Control.Monad.Catch Methods mask :: ((forall a. WriterT w m a -> WriterT w m a) -> WriterT w m b) -> WriterT w m b # uninterruptibleMask :: ((forall a. WriterT w m a -> WriterT w m a) -> WriterT w m b) -> WriterT w m b # generalBracket :: WriterT w m a -> (a -> ExitCase b -> WriterT w m c) -> (a -> WriterT w m b) -> WriterT w m (b, c) #
(MonadMask m, Monoid w) => MonadMask (WriterT w m)
Instance details Defined in Control.Monad.Catch Methods mask :: ((forall a. WriterT w m a -> WriterT w m a) -> WriterT w m b) -> WriterT w m b # uninterruptibleMask :: ((forall a. WriterT w m a -> WriterT w m a) -> WriterT w m b) -> WriterT w m b # generalBracket :: WriterT w m a -> (a -> ExitCase b -> WriterT w m c) -> (a -> WriterT w m b) -> WriterT w m (b, c) #
MonadMask m => MonadMask (ReaderT r m)
Instance details Defined in Control.Monad.Catch Methods mask :: ((forall a. ReaderT r m a -> ReaderT r m a) -> ReaderT r m b) -> ReaderT r m b # uninterruptibleMask :: ((forall a. ReaderT r m a -> ReaderT r m a) -> ReaderT r m b) -> ReaderT r m b # generalBracket :: ReaderT r m a -> (a -> ExitCase b -> ReaderT r m c) -> (a -> ReaderT r m b) -> ReaderT r m (b, c) #
(MonadMask m, Monoid w) => MonadMask (RWST r w s m)
Instance details Defined in Control.Monad.Catch Methods mask :: ((forall a. RWST r w s m a -> RWST r w s m a) -> RWST r w s m b) -> RWST r w s m b # uninterruptibleMask :: ((forall a. RWST r w s m a -> RWST r w s m a) -> RWST r w s m b) -> RWST r w s m b # generalBracket :: RWST r w s m a -> (a -> ExitCase b -> RWST r w s m c) -> (a -> RWST r w s m b) -> RWST r w s m (b, c) #
(MonadMask m, Monoid w) => MonadMask (RWST r w s m)
Instance details Defined in Control.Monad.Catch Methods mask :: ((forall a. RWST r w s m a -> RWST r w s m a) -> RWST r w s m b) -> RWST r w s m b # uninterruptibleMask :: ((forall a. RWST r w s m a -> RWST r w s m a) -> RWST r w s m b) -> RWST r w s m b # generalBracket :: RWST r w s m a -> (a -> ExitCase b -> RWST r w s m c) -> (a -> RWST r w s m b) -> RWST r w s m (b, c) #

class Hashable a where #

The class of types that can be converted to a hash value.

Minimal implementation: hashWithSalt.

Minimal complete definition

Nothing

Methods

hashWithSalt :: Int -> a -> Int infixl 0 #

Return a hash value for the argument, using the given salt.

The general contract of hashWithSalt is:

If two values are equal according to the == method, then applying the hashWithSalt method on each of the two values must produce the same integer result if the same salt is used in each case.
It is not required that if two values are unequal according to the == method, then applying the hashWithSalt method on each of the two values must produce distinct integer results. However, the programmer should be aware that producing distinct integer results for unequal values may improve the performance of hashing-based data structures.
This method can be used to compute different hash values for the same input by providing a different salt in each application of the method. This implies that any instance that defines hashWithSalt must make use of the salt in its implementation.

Instances

Hashable Bool
Instance details Defined in Data.Hashable.Class Methods hashWithSalt :: Int -> Bool -> Int # hash :: Bool -> Int #
Hashable Char
Instance details Defined in Data.Hashable.Class Methods hashWithSalt :: Int -> Char -> Int # hash :: Char -> Int #
Hashable Double	Note: prior to `hashable-1.3.0.0`, `hash 0.0 /= hash (-0.0)` The `hash` of NaN is not well defined. Since: hashable-1.3.0.0
Instance details Defined in Data.Hashable.Class Methods hashWithSalt :: Int -> Double -> Int # hash :: Double -> Int #
Hashable Float	Note: prior to `hashable-1.3.0.0`, `hash 0.0 /= hash (-0.0)` The `hash` of NaN is not well defined. Since: hashable-1.3.0.0
Instance details Defined in Data.Hashable.Class Methods hashWithSalt :: Int -> Float -> Int # hash :: Float -> Int #
Hashable Int
Instance details Defined in Data.Hashable.Class Methods hashWithSalt :: Int -> Int -> Int # hash :: Int -> Int #
Hashable Int8
Instance details Defined in Data.Hashable.Class Methods hashWithSalt :: Int -> Int8 -> Int # hash :: Int8 -> Int #
Hashable Int16
Instance details Defined in Data.Hashable.Class Methods hashWithSalt :: Int -> Int16 -> Int # hash :: Int16 -> Int #
Hashable Int32
Instance details Defined in Data.Hashable.Class Methods hashWithSalt :: Int -> Int32 -> Int # hash :: Int32 -> Int #
Hashable Int64
Instance details Defined in Data.Hashable.Class Methods hashWithSalt :: Int -> Int64 -> Int # hash :: Int64 -> Int #
Hashable Integer
Instance details Defined in Data.Hashable.Class Methods hashWithSalt :: Int -> Integer -> Int # hash :: Integer -> Int #
Hashable Natural
Instance details Defined in Data.Hashable.Class Methods hashWithSalt :: Int -> Natural -> Int # hash :: Natural -> Int #
Hashable Ordering
Instance details Defined in Data.Hashable.Class Methods hashWithSalt :: Int -> Ordering -> Int # hash :: Ordering -> Int #
Hashable Word
Instance details Defined in Data.Hashable.Class Methods hashWithSalt :: Int -> Word -> Int # hash :: Word -> Int #
Hashable Word8
Instance details Defined in Data.Hashable.Class Methods hashWithSalt :: Int -> Word8 -> Int # hash :: Word8 -> Int #
Hashable Word16
Instance details Defined in Data.Hashable.Class Methods hashWithSalt :: Int -> Word16 -> Int # hash :: Word16 -> Int #
Hashable Word32
Instance details Defined in Data.Hashable.Class Methods hashWithSalt :: Int -> Word32 -> Int # hash :: Word32 -> Int #
Hashable Word64
Instance details Defined in Data.Hashable.Class Methods hashWithSalt :: Int -> Word64 -> Int # hash :: Word64 -> Int #
Hashable SomeTypeRep
Instance details Defined in Data.Hashable.Class Methods hashWithSalt :: Int -> SomeTypeRep -> Int # hash :: SomeTypeRep -> Int #
Hashable ()
Instance details Defined in Data.Hashable.Class Methods hashWithSalt :: Int -> () -> Int # hash :: () -> Int #
Hashable BigNat
Instance details Defined in Data.Hashable.Class Methods hashWithSalt :: Int -> BigNat -> Int # hash :: BigNat -> Int #
Hashable Void
Instance details Defined in Data.Hashable.Class Methods hashWithSalt :: Int -> Void -> Int # hash :: Void -> Int #
Hashable Unique
Instance details Defined in Data.Hashable.Class Methods hashWithSalt :: Int -> Unique -> Int # hash :: Unique -> Int #
Hashable Version
Instance details Defined in Data.Hashable.Class Methods hashWithSalt :: Int -> Version -> Int # hash :: Version -> Int #
Hashable ThreadId
Instance details Defined in Data.Hashable.Class Methods hashWithSalt :: Int -> ThreadId -> Int # hash :: ThreadId -> Int #
Hashable WordPtr
Instance details Defined in Data.Hashable.Class Methods hashWithSalt :: Int -> WordPtr -> Int # hash :: WordPtr -> Int #
Hashable IntPtr
Instance details Defined in Data.Hashable.Class Methods hashWithSalt :: Int -> IntPtr -> Int # hash :: IntPtr -> Int #
Hashable Fingerprint	Since: hashable-1.3.0.0
Instance details Defined in Data.Hashable.Class Methods hashWithSalt :: Int -> Fingerprint -> Int # hash :: Fingerprint -> Int #
Hashable ShortByteString
Instance details Defined in Data.Hashable.Class Methods hashWithSalt :: Int -> ShortByteString -> Int # hash :: ShortByteString -> Int #
Hashable ByteString
Instance details Defined in Data.Hashable.Class Methods hashWithSalt :: Int -> ByteString -> Int # hash :: ByteString -> Int #
Hashable ByteString
Instance details Defined in Data.Hashable.Class Methods hashWithSalt :: Int -> ByteString -> Int # hash :: ByteString -> Int #
Hashable Text
Instance details Defined in Data.Hashable.Class Methods hashWithSalt :: Int -> Text -> Int # hash :: Text -> Int #
Hashable Text
Instance details Defined in Data.Hashable.Class Methods hashWithSalt :: Int -> Text -> Int # hash :: Text -> Int #
Hashable a => Hashable [a]
Instance details Defined in Data.Hashable.Class Methods hashWithSalt :: Int -> [a] -> Int # hash :: [a] -> Int #
Hashable a => Hashable (Maybe a)
Instance details Defined in Data.Hashable.Class Methods hashWithSalt :: Int -> Maybe a -> Int # hash :: Maybe a -> Int #
Hashable a => Hashable (Ratio a)
Instance details Defined in Data.Hashable.Class Methods hashWithSalt :: Int -> Ratio a -> Int # hash :: Ratio a -> Int #
Hashable (Ptr a)
Instance details Defined in Data.Hashable.Class Methods hashWithSalt :: Int -> Ptr a -> Int # hash :: Ptr a -> Int #
Hashable (FunPtr a)
Instance details Defined in Data.Hashable.Class Methods hashWithSalt :: Int -> FunPtr a -> Int # hash :: FunPtr a -> Int #
Hashable a => Hashable (Complex a)
Instance details Defined in Data.Hashable.Class Methods hashWithSalt :: Int -> Complex a -> Int # hash :: Complex a -> Int #
Hashable (Fixed a)
Instance details Defined in Data.Hashable.Class Methods hashWithSalt :: Int -> Fixed a -> Int # hash :: Fixed a -> Int #
Hashable a => Hashable (Min a)
Instance details Defined in Data.Hashable.Class Methods hashWithSalt :: Int -> Min a -> Int # hash :: Min a -> Int #
Hashable a => Hashable (Max a)
Instance details Defined in Data.Hashable.Class Methods hashWithSalt :: Int -> Max a -> Int # hash :: Max a -> Int #
Hashable a => Hashable (First a)
Instance details Defined in Data.Hashable.Class Methods hashWithSalt :: Int -> First a -> Int # hash :: First a -> Int #
Hashable a => Hashable (Last a)
Instance details Defined in Data.Hashable.Class Methods hashWithSalt :: Int -> Last a -> Int # hash :: Last a -> Int #
Hashable a => Hashable (WrappedMonoid a)
Instance details Defined in Data.Hashable.Class Methods hashWithSalt :: Int -> WrappedMonoid a -> Int # hash :: WrappedMonoid a -> Int #
Hashable a => Hashable (Option a)
Instance details Defined in Data.Hashable.Class Methods hashWithSalt :: Int -> Option a -> Int # hash :: Option a -> Int #
Hashable (StableName a)
Instance details Defined in Data.Hashable.Class Methods hashWithSalt :: Int -> StableName a -> Int # hash :: StableName a -> Int #
Hashable a => Hashable (Identity a)
Instance details Defined in Data.Hashable.Class Methods hashWithSalt :: Int -> Identity a -> Int # hash :: Identity a -> Int #
Hashable a => Hashable (NonEmpty a)
Instance details Defined in Data.Hashable.Class Methods hashWithSalt :: Int -> NonEmpty a -> Int # hash :: NonEmpty a -> Int #
Hashable (Hashed a)
Instance details Defined in Data.Hashable.Class Methods hashWithSalt :: Int -> Hashed a -> Int # hash :: Hashed a -> Int #
Hashable a => Hashable (HashSet a)
Instance details Defined in Data.HashSet.Base Methods hashWithSalt :: Int -> HashSet a -> Int # hash :: HashSet a -> Int #
(Hashable a, Hashable b) => Hashable (Either a b)
Instance details Defined in Data.Hashable.Class Methods hashWithSalt :: Int -> Either a b -> Int # hash :: Either a b -> Int #
Hashable (TypeRep a)
Instance details Defined in Data.Hashable.Class Methods hashWithSalt :: Int -> TypeRep a -> Int # hash :: TypeRep a -> Int #
(Hashable a1, Hashable a2) => Hashable (a1, a2)
Instance details Defined in Data.Hashable.Class Methods hashWithSalt :: Int -> (a1, a2) -> Int # hash :: (a1, a2) -> Int #
Hashable a => Hashable (Arg a b)	Note: Prior to `hashable-1.3.0.0` the hash computation included the second argument of `Arg` which wasn't consistent with its `Eq` instance. Since: hashable-1.3.0.0
Instance details Defined in Data.Hashable.Class Methods hashWithSalt :: Int -> Arg a b -> Int # hash :: Arg a b -> Int #
Hashable (Proxy a)
Instance details Defined in Data.Hashable.Class Methods hashWithSalt :: Int -> Proxy a -> Int # hash :: Proxy a -> Int #
(Hashable k, Hashable v) => Hashable (HashMap k v)
Instance details Defined in Data.HashMap.Base Methods hashWithSalt :: Int -> HashMap k v -> Int # hash :: HashMap k v -> Int #
(Hashable a1, Hashable a2, Hashable a3) => Hashable (a1, a2, a3)
Instance details Defined in Data.Hashable.Class Methods hashWithSalt :: Int -> (a1, a2, a3) -> Int # hash :: (a1, a2, a3) -> Int #
Hashable a => Hashable (Const a b)
Instance details Defined in Data.Hashable.Class Methods hashWithSalt :: Int -> Const a b -> Int # hash :: Const a b -> Int #
(Hashable a1, Hashable a2, Hashable a3, Hashable a4) => Hashable (a1, a2, a3, a4)
Instance details Defined in Data.Hashable.Class Methods hashWithSalt :: Int -> (a1, a2, a3, a4) -> Int # hash :: (a1, a2, a3, a4) -> Int #
(Hashable1 f, Hashable1 g, Hashable a) => Hashable (Product f g a)
Instance details Defined in Data.Hashable.Class Methods hashWithSalt :: Int -> Product f g a -> Int # hash :: Product f g a -> Int #
(Hashable1 f, Hashable1 g, Hashable a) => Hashable (Sum f g a)
Instance details Defined in Data.Hashable.Class Methods hashWithSalt :: Int -> Sum f g a -> Int # hash :: Sum f g a -> Int #
(Hashable a1, Hashable a2, Hashable a3, Hashable a4, Hashable a5) => Hashable (a1, a2, a3, a4, a5)
Instance details Defined in Data.Hashable.Class Methods hashWithSalt :: Int -> (a1, a2, a3, a4, a5) -> Int # hash :: (a1, a2, a3, a4, a5) -> Int #
(Hashable1 f, Hashable1 g, Hashable a) => Hashable (Compose f g a)	In general, `hash (Compose x) ≠ hash x`. However, `hashWithSalt` satisfies its variant of this equivalence.
Instance details Defined in Data.Hashable.Class Methods hashWithSalt :: Int -> Compose f g a -> Int # hash :: Compose f g a -> Int #
(Hashable a1, Hashable a2, Hashable a3, Hashable a4, Hashable a5, Hashable a6) => Hashable (a1, a2, a3, a4, a5, a6)
Instance details Defined in Data.Hashable.Class Methods hashWithSalt :: Int -> (a1, a2, a3, a4, a5, a6) -> Int # hash :: (a1, a2, a3, a4, a5, a6) -> Int #
(Hashable a1, Hashable a2, Hashable a3, Hashable a4, Hashable a5, Hashable a6, Hashable a7) => Hashable (a1, a2, a3, a4, a5, a6, a7)
Instance details Defined in Data.Hashable.Class Methods hashWithSalt :: Int -> (a1, a2, a3, a4, a5, a6, a7) -> Int # hash :: (a1, a2, a3, a4, a5, a6, a7) -> Int #

(^?) :: s -> Getting (First a) s a -> Maybe a infixl 8 #

s ^? t returns the 1st element t returns, or Nothing if t doesn't return anything. It's trivially implemented by passing the First monoid to the getter.

Safe head:

>>> [] ^? each
Nothing

>>> [1..3] ^? each
Just 1

Converting Either to Maybe:

>>> Left 1 ^? _Right
Nothing

>>> Right 1 ^? _Right
Just 1

A non-operator version of (^?) is called preview, and – like view – it's a bit more general than (^?) (it works in MonadReader). If you need the general version, you can get it from microlens-mtl; otherwise there's preview available in Lens.Micro.Extras.

(^..) :: s -> Getting (Endo [a]) s a -> [a] infixl 8 #

s ^.. t returns the list of all values that t gets from s.

A Maybe contains either 0 or 1 values:

>>> Just 3 ^.. _Just
[3]

Gathering all values in a list of tuples:

>>> [(1,2),(3,4)] ^.. each.each
[1,2,3,4]

(^.) :: s -> Getting a s a -> a infixl 8 #

(^.) applies a getter to a value; in other words, it gets a value out of a structure using a getter (which can be a lens, traversal, fold, etc.).

Getting 1st field of a tuple:

(^. _1) :: (a, b) -> a
(^. _1) = fst

When (^.) is used with a traversal, it combines all results using the Monoid instance for the resulting type. For instance, for lists it would be simple concatenation:

>>> ("str","ing") ^. each
"string"

The reason for this is that traversals use Applicative, and the Applicative instance for Const uses monoid concatenation to combine “effects” of Const.

A non-operator version of (^.) is called view, and it's a bit more general than (^.) (it works in MonadReader). If you need the general version, you can get it from microlens-mtl; otherwise there's view available in Lens.Micro.Extras.

set :: ASetter s t a b -> b -> s -> t #

set is a synonym for (.~).

Setting the 1st component of a pair:

set _1 :: x -> (a, b) -> (x, b)
set _1 = \x t -> (x, snd t)

Using it to rewrite (<$):

set mapped :: Functor f => a -> f b -> f a
set mapped = (<$)

(.~) :: ASetter s t a b -> b -> s -> t infixr 4 #

(.~) assigns a value to the target. It's the same thing as using (%~) with const:

l .~ x = l %~ const x

See set if you want a non-operator synonym.

Here it is used to change 2 fields of a 3-tuple:

>>> (0,0,0) & _1 .~ 1 & _3 .~ 3
(1,0,3)

over :: ASetter s t a b -> (a -> b) -> s -> t #

over is a synonym for (%~).

Getting fmap in a roundabout way:

over mapped :: Functor f => (a -> b) -> f a -> f b
over mapped = fmap

Applying a function to both components of a pair:

over both :: (a -> b) -> (a, a) -> (b, b)
over both = \f t -> (f (fst t), f (snd t))

Using over _2 as a replacement for second:

>>> over _2 show (10,20)
(10,"20")

(%~) :: ASetter s t a b -> (a -> b) -> s -> t infixr 4 #

(%~) applies a function to the target; an alternative explanation is that it is an inverse of sets, which turns a setter into an ordinary function. mapped %~ reverse is the same thing as fmap reverse.

See over if you want a non-operator synonym.

Negating the 1st element of a pair:

>>> (1,2) & _1 %~ negate
(-1,2)

Turning all Lefts in a list to upper case:

>>> (mapped._Left.mapped %~ toUpper) [Left "foo", Right "bar"]
[Left "FOO",Right "bar"]

_1 :: Field1 s t a b => Lens s t a b #

Gives access to the 1st field of a tuple (up to 5-tuples).

Getting the 1st component:

>>> (1,2,3,4,5) ^. _1
1

Setting the 1st component:

>>> (1,2,3) & _1 .~ 10
(10,2,3)

Note that this lens is lazy, and can set fields even of undefined:

>>> set _1 10 undefined :: (Int, Int)
(10,*** Exception: Prelude.undefined

This is done to avoid violating a lens law stating that you can get back what you put:

>>> view _1 . set _1 10 $ (undefined :: (Int, Int))
10

The implementation (for 2-tuples) is:

_1 f t = (,) <$> f    (fst t)
             <*> pure (snd t)

or, alternatively,

_1 f ~(a,b) = (\a' -> (a',b)) <$> f a

(where ~ means a lazy pattern).

_2, _3, _4, and _5 are also available (see below).

_2 :: Field2 s t a b => Lens s t a b #

_3 :: Field3 s t a b => Lens s t a b #

_4 :: Field4 s t a b => Lens s t a b #

_5 :: Field5 s t a b => Lens s t a b #

type Lens s t a b = forall (f :: Type -> Type). Functor f => (a -> f b) -> s -> f t #

Lens s t a b is the lowest common denominator of a setter and a getter, something that has the power of both; it has a Functor constraint, and since both Const and Identity are functors, it can be used whenever a getter or a setter is needed.

a is the type of the value inside of structure
b is the type of the replaced value
s is the type of the whole structure
t is the type of the structure after replacing a in it with b

type Lens' s a = Lens s s a a #

This is a type alias for monomorphic lenses which don't change the type of the container (or of the value inside).

type Traversal s t a b = forall (f :: Type -> Type). Applicative f => (a -> f b) -> s -> f t #

Traversal s t a b is a generalisation of Lens which allows many targets (possibly 0). It's achieved by changing the constraint to Applicative instead of Functor – indeed, the point of Applicative is that you can combine effects, which is just what we need to have many targets.

Ultimately, traversals should follow 2 laws:

t pure ≡ pure
fmap (t f) . t g ≡ getCompose . t (Compose . fmap f . g)

The 1st law states that you can't change the shape of the structure or do anything funny with elements (traverse elements which aren't in the structure, create new elements out of thin air, etc.). The 2nd law states that you should be able to fuse 2 identical traversals into one. For a more detailed explanation of the laws, see this blog post (if you prefer rambling blog posts), or The Essence Of The Iterator Pattern (if you prefer papers).

Traversing any value twice is a violation of traversal laws. You can, however, traverse values in any order.

type Traversal' s a = Traversal s s a a #

This is a type alias for monomorphic traversals which don't change the type of the container (or of the values inside).

modify :: MonadState s m => (s -> s) -> m () #

Monadic state transformer.

Maps an old state to a new state inside a state monad. The old state is thrown away.

     Main> :t modify ((+1) :: Int -> Int)
     modify (...) :: (MonadState Int a) => a ()

This says that modify (+1) acts over any Monad that is a member of the MonadState class, with an Int state.

gets :: MonadState s m => (s -> a) -> m a #

Gets specific component of the state, using a projection function supplied.

asks #

Arguments

:: MonadReader r m
=> (r -> a)	The selector function to apply to the environment.
-> m a

Retrieves a function of the current environment.

class Monad m => MonadReader r (m :: Type -> Type) | m -> r where #

See examples in Control.Monad.Reader. Note, the partially applied function type (->) r is a simple reader monad. See the instance declaration below.

Minimal complete definition

(ask | reader), local

Methods

ask :: m r #

Retrieves the monad environment.

local #

Arguments

:: (r -> r)	The function to modify the environment.
-> m a	`Reader` to run in the modified environment.
-> m a

Executes a computation in a modified environment.

reader #

Arguments

:: (r -> a)	The selector function to apply to the environment.
-> m a

Retrieves a function of the current environment.

Instances

MonadReader r m => MonadReader r (MaybeT m)
Instance details Defined in Control.Monad.Reader.Class Methods ask :: MaybeT m r # local :: (r -> r) -> MaybeT m a -> MaybeT m a # reader :: (r -> a) -> MaybeT m a #
MonadReader r m => MonadReader r (ListT m)
Instance details Defined in Control.Monad.Reader.Class Methods ask :: ListT m r # local :: (r -> r) -> ListT m a -> ListT m a # reader :: (r -> a) -> ListT m a #
(Monoid w, MonadReader r m) => MonadReader r (WriterT w m)
Instance details Defined in Control.Monad.Reader.Class Methods ask :: WriterT w m r # local :: (r -> r) -> WriterT w m a -> WriterT w m a # reader :: (r -> a) -> WriterT w m a #
(Monoid w, MonadReader r m) => MonadReader r (WriterT w m)
Instance details Defined in Control.Monad.Reader.Class Methods ask :: WriterT w m r # local :: (r -> r) -> WriterT w m a -> WriterT w m a # reader :: (r -> a) -> WriterT w m a #
MonadReader r m => MonadReader r (StateT s m)
Instance details Defined in Control.Monad.Reader.Class Methods ask :: StateT s m r # local :: (r -> r) -> StateT s m a -> StateT s m a # reader :: (r -> a) -> StateT s m a #
MonadReader r m => MonadReader r (StateT s m)
Instance details Defined in Control.Monad.Reader.Class Methods ask :: StateT s m r # local :: (r -> r) -> StateT s m a -> StateT s m a # reader :: (r -> a) -> StateT s m a #
MonadReader r m => MonadReader r (IdentityT m)
Instance details Defined in Control.Monad.Reader.Class Methods ask :: IdentityT m r # local :: (r -> r) -> IdentityT m a -> IdentityT m a # reader :: (r -> a) -> IdentityT m a #
MonadReader r m => MonadReader r (ExceptT e m)	Since: mtl-2.2
Instance details Defined in Control.Monad.Reader.Class Methods ask :: ExceptT e m r # local :: (r -> r) -> ExceptT e m a -> ExceptT e m a # reader :: (r -> a) -> ExceptT e m a #
(Error e, MonadReader r m) => MonadReader r (ErrorT e m)
Instance details Defined in Control.Monad.Reader.Class Methods ask :: ErrorT e m r # local :: (r -> r) -> ErrorT e m a -> ErrorT e m a # reader :: (r -> a) -> ErrorT e m a #
Monad m => MonadReader r (ReaderT r m)
Instance details Defined in Control.Monad.Reader.Class Methods ask :: ReaderT r m r # local :: (r -> r) -> ReaderT r m a -> ReaderT r m a # reader :: (r -> a) -> ReaderT r m a #
MonadReader r ((->) r :: Type -> Type)
Instance details Defined in Control.Monad.Reader.Class Methods ask :: r -> r # local :: (r -> r) -> (r -> a) -> r -> a # reader :: (r -> a) -> r -> a #
MonadReader r' m => MonadReader r' (ContT r m)
Instance details Defined in Control.Monad.Reader.Class Methods ask :: ContT r m r' # local :: (r' -> r') -> ContT r m a -> ContT r m a # reader :: (r' -> a) -> ContT r m a #
(Monad m, Monoid w) => MonadReader r (RWST r w s m)
Instance details Defined in Control.Monad.Reader.Class Methods ask :: RWST r w s m r # local :: (r -> r) -> RWST r w s m a -> RWST r w s m a # reader :: (r -> a) -> RWST r w s m a #
(Monad m, Monoid w) => MonadReader r (RWST r w s m)
Instance details Defined in Control.Monad.Reader.Class Methods ask :: RWST r w s m r # local :: (r -> r) -> RWST r w s m a -> RWST r w s m a # reader :: (r -> a) -> RWST r w s m a #

class Monad m => MonadState s (m :: Type -> Type) | m -> s where #

Minimal definition is either both of get and put or just state

Minimal complete definition

state | get, put

Methods

get :: m s #

Return the state from the internals of the monad.

put :: s -> m () #

Replace the state inside the monad.

state :: (s -> (a, s)) -> m a #

Embed a simple state action into the monad.

Instances

MonadState s m => MonadState s (MaybeT m)
Instance details Defined in Control.Monad.State.Class Methods get :: MaybeT m s # put :: s -> MaybeT m () # state :: (s -> (a, s)) -> MaybeT m a #
MonadState s m => MonadState s (ListT m)
Instance details Defined in Control.Monad.State.Class Methods get :: ListT m s # put :: s -> ListT m () # state :: (s -> (a, s)) -> ListT m a #
(Monoid w, MonadState s m) => MonadState s (WriterT w m)
Instance details Defined in Control.Monad.State.Class Methods get :: WriterT w m s # put :: s -> WriterT w m () # state :: (s -> (a, s)) -> WriterT w m a #
(Monoid w, MonadState s m) => MonadState s (WriterT w m)
Instance details Defined in Control.Monad.State.Class Methods get :: WriterT w m s # put :: s -> WriterT w m () # state :: (s -> (a, s)) -> WriterT w m a #
Monad m => MonadState s (StateT s m)
Instance details Defined in Control.Monad.State.Class Methods get :: StateT s m s # put :: s -> StateT s m () # state :: (s -> (a, s)) -> StateT s m a #
Monad m => MonadState s (StateT s m)
Instance details Defined in Control.Monad.State.Class Methods get :: StateT s m s # put :: s -> StateT s m () # state :: (s -> (a, s)) -> StateT s m a #
MonadState s m => MonadState s (IdentityT m)
Instance details Defined in Control.Monad.State.Class Methods get :: IdentityT m s # put :: s -> IdentityT m () # state :: (s -> (a, s)) -> IdentityT m a #
MonadState s m => MonadState s (ExceptT e m)	Since: mtl-2.2
Instance details Defined in Control.Monad.State.Class Methods get :: ExceptT e m s # put :: s -> ExceptT e m () # state :: (s -> (a, s)) -> ExceptT e m a #
(Error e, MonadState s m) => MonadState s (ErrorT e m)
Instance details Defined in Control.Monad.State.Class Methods get :: ErrorT e m s # put :: s -> ErrorT e m () # state :: (s -> (a, s)) -> ErrorT e m a #
MonadState s m => MonadState s (ReaderT r m)
Instance details Defined in Control.Monad.State.Class Methods get :: ReaderT r m s # put :: s -> ReaderT r m () # state :: (s -> (a, s)) -> ReaderT r m a #
MonadState s m => MonadState s (ContT r m)
Instance details Defined in Control.Monad.State.Class Methods get :: ContT r m s # put :: s -> ContT r m () # state :: (s -> (a, s)) -> ContT r m a #
(Monad m, Monoid w) => MonadState s (RWST r w s m)
Instance details Defined in Control.Monad.State.Class Methods get :: RWST r w s m s # put :: s -> RWST r w s m () # state :: (s -> (a, s)) -> RWST r w s m a #
(Monad m, Monoid w) => MonadState s (RWST r w s m)
Instance details Defined in Control.Monad.State.Class Methods get :: RWST r w s m s # put :: s -> RWST r w s m () # state :: (s -> (a, s)) -> RWST r w s m a #

newtype ReaderT r (m :: k -> Type) (a :: k) :: forall k. Type -> (k -> Type) -> k -> Type #

The reader monad transformer, which adds a read-only environment to the given monad.

The return function ignores the environment, while >>= passes the inherited environment to both subcomputations.

Constructors

ReaderT
Fields runReaderT :: r -> m a

Instances

Monad m => MonadReader r (ReaderT r m)
Instance details Defined in Control.Monad.Reader.Class Methods ask :: ReaderT r m r # local :: (r -> r) -> ReaderT r m a -> ReaderT r m a # reader :: (r -> a) -> ReaderT r m a #
MonadState s m => MonadState s (ReaderT r m)
Instance details Defined in Control.Monad.State.Class Methods get :: ReaderT r m s # put :: s -> ReaderT r m () # state :: (s -> (a, s)) -> ReaderT r m a #
MonadError e m => MonadError e (ReaderT r m)
Instance details Defined in Control.Monad.Error.Class Methods throwError :: e -> ReaderT r m a # catchError :: ReaderT r m a -> (e -> ReaderT r m a) -> ReaderT r m a #
MonadTrans (ReaderT r :: (Type -> Type) -> Type -> Type)
Instance details Defined in Control.Monad.Trans.Reader Methods lift :: Monad m => m a -> ReaderT r m a #
Monad m => Monad (ReaderT r m)
Instance details Defined in Control.Monad.Trans.Reader Methods (>>=) :: ReaderT r m a -> (a -> ReaderT r m b) -> ReaderT r m b # (>>) :: ReaderT r m a -> ReaderT r m b -> ReaderT r m b # return :: a -> ReaderT r m a # fail :: String -> ReaderT r m a #
Functor m => Functor (ReaderT r m)
Instance details Defined in Control.Monad.Trans.Reader Methods fmap :: (a -> b) -> ReaderT r m a -> ReaderT r m b # (<$) :: a -> ReaderT r m b -> ReaderT r m a #
MonadFix m => MonadFix (ReaderT r m)
Instance details Defined in Control.Monad.Trans.Reader Methods mfix :: (a -> ReaderT r m a) -> ReaderT r m a #
MonadFail m => MonadFail (ReaderT r m)
Instance details Defined in Control.Monad.Trans.Reader Methods fail :: String -> ReaderT r m a #
Applicative m => Applicative (ReaderT r m)
Instance details Defined in Control.Monad.Trans.Reader Methods pure :: a -> ReaderT r m a # (<>) :: ReaderT r m (a -> b) -> ReaderT r m a -> ReaderT r m b # liftA2 :: (a -> b -> c) -> ReaderT r m a -> ReaderT r m b -> ReaderT r m c # (>) :: ReaderT r m a -> ReaderT r m b -> ReaderT r m b # (<*) :: ReaderT r m a -> ReaderT r m b -> ReaderT r m a #
Contravariant m => Contravariant (ReaderT r m)
Instance details Defined in Control.Monad.Trans.Reader Methods contramap :: (a -> b) -> ReaderT r m b -> ReaderT r m a # (>$) :: b -> ReaderT r m b -> ReaderT r m a #
MonadZip m => MonadZip (ReaderT r m)
Instance details Defined in Control.Monad.Trans.Reader Methods mzip :: ReaderT r m a -> ReaderT r m b -> ReaderT r m (a, b) # mzipWith :: (a -> b -> c) -> ReaderT r m a -> ReaderT r m b -> ReaderT r m c # munzip :: ReaderT r m (a, b) -> (ReaderT r m a, ReaderT r m b) #
MonadIO m => MonadIO (ReaderT r m)
Instance details Defined in Control.Monad.Trans.Reader Methods liftIO :: IO a -> ReaderT r m a #
Alternative m => Alternative (ReaderT r m)
Instance details Defined in Control.Monad.Trans.Reader Methods empty :: ReaderT r m a # (<\|>) :: ReaderT r m a -> ReaderT r m a -> ReaderT r m a # some :: ReaderT r m a -> ReaderT r m [a] # many :: ReaderT r m a -> ReaderT r m [a] #
MonadPlus m => MonadPlus (ReaderT r m)
Instance details Defined in Control.Monad.Trans.Reader Methods mzero :: ReaderT r m a # mplus :: ReaderT r m a -> ReaderT r m a -> ReaderT r m a #
MonadThrow m => MonadThrow (ReaderT r m)
Instance details Defined in Control.Monad.Catch Methods throwM :: Exception e => e -> ReaderT r m a #
MonadCatch m => MonadCatch (ReaderT r m)
Instance details Defined in Control.Monad.Catch Methods catch :: Exception e => ReaderT r m a -> (e -> ReaderT r m a) -> ReaderT r m a #
MonadMask m => MonadMask (ReaderT r m)
Instance details Defined in Control.Monad.Catch Methods mask :: ((forall a. ReaderT r m a -> ReaderT r m a) -> ReaderT r m b) -> ReaderT r m b # uninterruptibleMask :: ((forall a. ReaderT r m a -> ReaderT r m a) -> ReaderT r m b) -> ReaderT r m b # generalBracket :: ReaderT r m a -> (a -> ExitCase b -> ReaderT r m c) -> (a -> ReaderT r m b) -> ReaderT r m (b, c) #

type Reader r = ReaderT r Identity #

The parameterizable reader monad.

Computations are functions of a shared environment.

The return function ignores the environment, while >>= passes the inherited environment to both subcomputations.

preuse :: MonadState s m => Getting (First a) s a -> m (Maybe a) #

preuse is (^?) (or preview) which implicitly operates on the state – it takes the state and applies a traversal (or fold) to it to extract the 1st element the traversal points at.

preuse l = gets (preview l)

use :: MonadState s m => Getting a s a -> m a #

use is (^.) (or view) which implicitly operates on the state; for instance, if your state is a record containing a field foo, you can write

x <- use foo

to extract foo from the state. In other words, use is the same as gets, but for getters instead of functions.

The implementation of use is straightforward:

use l = gets (view l)

If you need to extract something with a fold or traversal, you need preuse.

preview :: MonadReader s m => Getting (First a) s a -> m (Maybe a) #

preview is a synonym for (^?), generalised for MonadReader (just like view, which is a synonym for (^.)).

>>> preview each [1..5]
Just 1

view :: MonadReader s m => Getting a s a -> m a #

view is a synonym for (^.), generalised for MonadReader (we are able to use it instead of (^.) since functions are instances of the MonadReader class):

>>> view _1 (1, 2)
1

When you're using Reader for config and your config type has lenses generated for it, most of the time you'll be using view instead of asks:

doSomething :: (MonadReader Config m) => m Int
doSomething = do
  thingy        <- view setting1  -- same as “asks (^. setting1)”
  anotherThingy <- view setting2
  ...

class MonadTrans (t :: (Type -> Type) -> Type -> Type) where #

The class of monad transformers. Instances should satisfy the following laws, which state that lift is a monad transformation:

```
lift . return = return
```
```
lift (m >>= f) = lift m >>= (lift . f)
```

Methods

lift :: Monad m => m a -> t m a #

Lift a computation from the argument monad to the constructed monad.

Instances

MonadTrans MaybeT
Instance details Defined in Control.Monad.Trans.Maybe Methods lift :: Monad m => m a -> MaybeT m a #
MonadTrans (ExceptT e)
Instance details Defined in Control.Monad.Trans.Except Methods lift :: Monad m => m a -> ExceptT e m a #
MonadTrans (IdentityT :: (Type -> Type) -> Type -> Type)
Instance details Defined in Control.Monad.Trans.Identity Methods lift :: Monad m => m a -> IdentityT m a #
MonadTrans (ErrorT e)
Instance details Defined in Control.Monad.Trans.Error Methods lift :: Monad m => m a -> ErrorT e m a #
MonadTrans (StateT s)
Instance details Defined in Control.Monad.Trans.State.Strict Methods lift :: Monad m => m a -> StateT s m a #
MonadTrans (ReaderT r :: (Type -> Type) -> Type -> Type)
Instance details Defined in Control.Monad.Trans.Reader Methods lift :: Monad m => m a -> ReaderT r m a #

data IdentityT (f :: k -> Type) (a :: k) :: forall k. (k -> Type) -> k -> Type #

The trivial monad transformer, which maps a monad to an equivalent monad.

Instances

MonadReader r m => MonadReader r (IdentityT m)
Instance details Defined in Control.Monad.Reader.Class Methods ask :: IdentityT m r # local :: (r -> r) -> IdentityT m a -> IdentityT m a # reader :: (r -> a) -> IdentityT m a #
MonadState s m => MonadState s (IdentityT m)
Instance details Defined in Control.Monad.State.Class Methods get :: IdentityT m s # put :: s -> IdentityT m () # state :: (s -> (a, s)) -> IdentityT m a #
MonadError e m => MonadError e (IdentityT m)
Instance details Defined in Control.Monad.Error.Class Methods throwError :: e -> IdentityT m a # catchError :: IdentityT m a -> (e -> IdentityT m a) -> IdentityT m a #
MonadTrans (IdentityT :: (Type -> Type) -> Type -> Type)
Instance details Defined in Control.Monad.Trans.Identity Methods lift :: Monad m => m a -> IdentityT m a #
Monad m => Monad (IdentityT m)
Instance details Defined in Control.Monad.Trans.Identity Methods (>>=) :: IdentityT m a -> (a -> IdentityT m b) -> IdentityT m b # (>>) :: IdentityT m a -> IdentityT m b -> IdentityT m b # return :: a -> IdentityT m a # fail :: String -> IdentityT m a #
Functor m => Functor (IdentityT m)
Instance details Defined in Control.Monad.Trans.Identity Methods fmap :: (a -> b) -> IdentityT m a -> IdentityT m b # (<$) :: a -> IdentityT m b -> IdentityT m a #
MonadFix m => MonadFix (IdentityT m)
Instance details Defined in Control.Monad.Trans.Identity Methods mfix :: (a -> IdentityT m a) -> IdentityT m a #
MonadFail m => MonadFail (IdentityT m)
Instance details Defined in Control.Monad.Trans.Identity Methods fail :: String -> IdentityT m a #
Applicative m => Applicative (IdentityT m)
Instance details Defined in Control.Monad.Trans.Identity Methods pure :: a -> IdentityT m a # (<>) :: IdentityT m (a -> b) -> IdentityT m a -> IdentityT m b # liftA2 :: (a -> b -> c) -> IdentityT m a -> IdentityT m b -> IdentityT m c # (>) :: IdentityT m a -> IdentityT m b -> IdentityT m b # (<*) :: IdentityT m a -> IdentityT m b -> IdentityT m a #
Foldable f => Foldable (IdentityT f)
Instance details Defined in Control.Monad.Trans.Identity Methods fold :: Monoid m => IdentityT f m -> m # foldMap :: Monoid m => (a -> m) -> IdentityT f a -> m # foldr :: (a -> b -> b) -> b -> IdentityT f a -> b # foldr' :: (a -> b -> b) -> b -> IdentityT f a -> b # foldl :: (b -> a -> b) -> b -> IdentityT f a -> b # foldl' :: (b -> a -> b) -> b -> IdentityT f a -> b # foldr1 :: (a -> a -> a) -> IdentityT f a -> a # foldl1 :: (a -> a -> a) -> IdentityT f a -> a # toList :: IdentityT f a -> [a] # null :: IdentityT f a -> Bool # length :: IdentityT f a -> Int # elem :: Eq a => a -> IdentityT f a -> Bool # maximum :: Ord a => IdentityT f a -> a # minimum :: Ord a => IdentityT f a -> a # sum :: Num a => IdentityT f a -> a # product :: Num a => IdentityT f a -> a #
Traversable f => Traversable (IdentityT f)
Instance details Defined in Control.Monad.Trans.Identity Methods traverse :: Applicative f0 => (a -> f0 b) -> IdentityT f a -> f0 (IdentityT f b) # sequenceA :: Applicative f0 => IdentityT f (f0 a) -> f0 (IdentityT f a) # mapM :: Monad m => (a -> m b) -> IdentityT f a -> m (IdentityT f b) # sequence :: Monad m => IdentityT f (m a) -> m (IdentityT f a) #
Contravariant f => Contravariant (IdentityT f)
Instance details Defined in Control.Monad.Trans.Identity Methods contramap :: (a -> b) -> IdentityT f b -> IdentityT f a # (>$) :: b -> IdentityT f b -> IdentityT f a #
Eq1 f => Eq1 (IdentityT f)
Instance details Defined in Control.Monad.Trans.Identity Methods liftEq :: (a -> b -> Bool) -> IdentityT f a -> IdentityT f b -> Bool #
Ord1 f => Ord1 (IdentityT f)
Instance details Defined in Control.Monad.Trans.Identity Methods liftCompare :: (a -> b -> Ordering) -> IdentityT f a -> IdentityT f b -> Ordering #
Read1 f => Read1 (IdentityT f)
Instance details Defined in Control.Monad.Trans.Identity Methods liftReadsPrec :: (Int -> ReadS a) -> ReadS [a] -> Int -> ReadS (IdentityT f a) # liftReadList :: (Int -> ReadS a) -> ReadS [a] -> ReadS [IdentityT f a] # liftReadPrec :: ReadPrec a -> ReadPrec [a] -> ReadPrec (IdentityT f a) # liftReadListPrec :: ReadPrec a -> ReadPrec [a] -> ReadPrec [IdentityT f a] #
Show1 f => Show1 (IdentityT f)
Instance details Defined in Control.Monad.Trans.Identity Methods liftShowsPrec :: (Int -> a -> ShowS) -> ([a] -> ShowS) -> Int -> IdentityT f a -> ShowS # liftShowList :: (Int -> a -> ShowS) -> ([a] -> ShowS) -> [IdentityT f a] -> ShowS #
MonadZip m => MonadZip (IdentityT m)
Instance details Defined in Control.Monad.Trans.Identity Methods mzip :: IdentityT m a -> IdentityT m b -> IdentityT m (a, b) # mzipWith :: (a -> b -> c) -> IdentityT m a -> IdentityT m b -> IdentityT m c # munzip :: IdentityT m (a, b) -> (IdentityT m a, IdentityT m b) #
MonadIO m => MonadIO (IdentityT m)
Instance details Defined in Control.Monad.Trans.Identity Methods liftIO :: IO a -> IdentityT m a #
Alternative m => Alternative (IdentityT m)
Instance details Defined in Control.Monad.Trans.Identity Methods empty :: IdentityT m a # (<\|>) :: IdentityT m a -> IdentityT m a -> IdentityT m a # some :: IdentityT m a -> IdentityT m [a] # many :: IdentityT m a -> IdentityT m [a] #
MonadPlus m => MonadPlus (IdentityT m)
Instance details Defined in Control.Monad.Trans.Identity Methods mzero :: IdentityT m a # mplus :: IdentityT m a -> IdentityT m a -> IdentityT m a #
MonadThrow m => MonadThrow (IdentityT m)
Instance details Defined in Control.Monad.Catch Methods throwM :: Exception e => e -> IdentityT m a #
MonadCatch m => MonadCatch (IdentityT m)
Instance details Defined in Control.Monad.Catch Methods catch :: Exception e => IdentityT m a -> (e -> IdentityT m a) -> IdentityT m a #
MonadMask m => MonadMask (IdentityT m)
Instance details Defined in Control.Monad.Catch Methods mask :: ((forall a. IdentityT m a -> IdentityT m a) -> IdentityT m b) -> IdentityT m b # uninterruptibleMask :: ((forall a. IdentityT m a -> IdentityT m a) -> IdentityT m b) -> IdentityT m b # generalBracket :: IdentityT m a -> (a -> ExitCase b -> IdentityT m c) -> (a -> IdentityT m b) -> IdentityT m (b, c) #
(Eq1 f, Eq a) => Eq (IdentityT f a)
Instance details Defined in Control.Monad.Trans.Identity Methods (==) :: IdentityT f a -> IdentityT f a -> Bool # (/=) :: IdentityT f a -> IdentityT f a -> Bool #
(Ord1 f, Ord a) => Ord (IdentityT f a)
Instance details Defined in Control.Monad.Trans.Identity Methods compare :: IdentityT f a -> IdentityT f a -> Ordering # (<) :: IdentityT f a -> IdentityT f a -> Bool # (<=) :: IdentityT f a -> IdentityT f a -> Bool # (>) :: IdentityT f a -> IdentityT f a -> Bool # (>=) :: IdentityT f a -> IdentityT f a -> Bool # max :: IdentityT f a -> IdentityT f a -> IdentityT f a # min :: IdentityT f a -> IdentityT f a -> IdentityT f a #
(Read1 f, Read a) => Read (IdentityT f a)
Instance details Defined in Control.Monad.Trans.Identity Methods readsPrec :: Int -> ReadS (IdentityT f a) # readList :: ReadS [IdentityT f a] # readPrec :: ReadPrec (IdentityT f a) # readListPrec :: ReadPrec [IdentityT f a] #
(Show1 f, Show a) => Show (IdentityT f a)
Instance details Defined in Control.Monad.Trans.Identity Methods showsPrec :: Int -> IdentityT f a -> ShowS # show :: IdentityT f a -> String # showList :: [IdentityT f a] -> ShowS #

modify' :: MonadState s m => (s -> s) -> m () #

A variant of modify in which the computation is strict in the new state.

Since: mtl-2.2

runExceptT :: ExceptT e m a -> m (Either e a) #

The inverse of ExceptT.

runReader #

Arguments

:: Reader r a	A `Reader` to run.
-> r	An initial environment.
-> a

Runs a Reader and extracts the final value from it. (The inverse of reader.)

newtype StateT s (m :: Type -> Type) a #

A state transformer monad parameterized by:

s - The state.
m - The inner monad.

The return function leaves the state unchanged, while >>= uses the final state of the first computation as the initial state of the second.

Constructors

StateT
Fields runStateT :: s -> m (a, s)

Instances

MonadReader r m => MonadReader r (StateT s m)
Instance details Defined in Control.Monad.Reader.Class Methods ask :: StateT s m r # local :: (r -> r) -> StateT s m a -> StateT s m a # reader :: (r -> a) -> StateT s m a #
Monad m => MonadState s (StateT s m)
Instance details Defined in Control.Monad.State.Class Methods get :: StateT s m s # put :: s -> StateT s m () # state :: (s -> (a, s)) -> StateT s m a #
MonadError e m => MonadError e (StateT s m)
Instance details Defined in Control.Monad.Error.Class Methods throwError :: e -> StateT s m a # catchError :: StateT s m a -> (e -> StateT s m a) -> StateT s m a #
MonadTrans (StateT s)
Instance details Defined in Control.Monad.Trans.State.Strict Methods lift :: Monad m => m a -> StateT s m a #
Monad m => Monad (StateT s m)
Instance details Defined in Control.Monad.Trans.State.Strict Methods (>>=) :: StateT s m a -> (a -> StateT s m b) -> StateT s m b # (>>) :: StateT s m a -> StateT s m b -> StateT s m b # return :: a -> StateT s m a # fail :: String -> StateT s m a #
Functor m => Functor (StateT s m)
Instance details Defined in Control.Monad.Trans.State.Strict Methods fmap :: (a -> b) -> StateT s m a -> StateT s m b # (<$) :: a -> StateT s m b -> StateT s m a #
MonadFix m => MonadFix (StateT s m)
Instance details Defined in Control.Monad.Trans.State.Strict Methods mfix :: (a -> StateT s m a) -> StateT s m a #
MonadFail m => MonadFail (StateT s m)
Instance details Defined in Control.Monad.Trans.State.Strict Methods fail :: String -> StateT s m a #
(Functor m, Monad m) => Applicative (StateT s m)
Instance details Defined in Control.Monad.Trans.State.Strict Methods pure :: a -> StateT s m a # (<>) :: StateT s m (a -> b) -> StateT s m a -> StateT s m b # liftA2 :: (a -> b -> c) -> StateT s m a -> StateT s m b -> StateT s m c # (>) :: StateT s m a -> StateT s m b -> StateT s m b # (<*) :: StateT s m a -> StateT s m b -> StateT s m a #
Contravariant m => Contravariant (StateT s m)
Instance details Defined in Control.Monad.Trans.State.Strict Methods contramap :: (a -> b) -> StateT s m b -> StateT s m a # (>$) :: b -> StateT s m b -> StateT s m a #
MonadIO m => MonadIO (StateT s m)
Instance details Defined in Control.Monad.Trans.State.Strict Methods liftIO :: IO a -> StateT s m a #
(Functor m, MonadPlus m) => Alternative (StateT s m)
Instance details Defined in Control.Monad.Trans.State.Strict Methods empty :: StateT s m a # (<\|>) :: StateT s m a -> StateT s m a -> StateT s m a # some :: StateT s m a -> StateT s m [a] # many :: StateT s m a -> StateT s m [a] #
MonadPlus m => MonadPlus (StateT s m)
Instance details Defined in Control.Monad.Trans.State.Strict Methods mzero :: StateT s m a # mplus :: StateT s m a -> StateT s m a -> StateT s m a #
MonadThrow m => MonadThrow (StateT s m)
Instance details Defined in Control.Monad.Catch Methods throwM :: Exception e => e -> StateT s m a #
MonadCatch m => MonadCatch (StateT s m)
Instance details Defined in Control.Monad.Catch Methods catch :: Exception e => StateT s m a -> (e -> StateT s m a) -> StateT s m a #
MonadMask m => MonadMask (StateT s m)
Instance details Defined in Control.Monad.Catch Methods mask :: ((forall a. StateT s m a -> StateT s m a) -> StateT s m b) -> StateT s m b # uninterruptibleMask :: ((forall a. StateT s m a -> StateT s m a) -> StateT s m b) -> StateT s m b # generalBracket :: StateT s m a -> (a -> ExitCase b -> StateT s m c) -> (a -> StateT s m b) -> StateT s m (b, c) #

type State s = StateT s Identity #

A state monad parameterized by the type s of the state to carry.

The return function leaves the state unchanged, while >>= uses the final state of the first computation as the initial state of the second.

runState #

Arguments

:: State s a	state-passing computation to execute
-> s	initial state
-> (a, s)	return value and final state

Unwrap a state monad computation as a function. (The inverse of state.)

evalState #

Arguments

:: State s a	state-passing computation to execute
-> s	initial value
-> a	return value of the state computation

Evaluate a state computation with the given initial state and return the final value, discarding the final state.

```
evalState m s = fst (runState m s)
```

execState #

Arguments

:: State s a	state-passing computation to execute
-> s	initial value
-> s	final state

Evaluate a state computation with the given initial state and return the final state, discarding the final value.

```
execState m s = snd (runState m s)
```

withState :: (s -> s) -> State s a -> State s a #

withState f m executes action m on a state modified by applying f.

```
withState f m = modify f >> m
```

evalStateT :: Monad m => StateT s m a -> s -> m a #

Evaluate a state computation with the given initial state and return the final value, discarding the final state.

evalStateT m s = liftM fst (runStateT m s)

execStateT :: Monad m => StateT s m a -> s -> m s #

Evaluate a state computation with the given initial state and return the final state, discarding the final value.

execStateT m s = liftM snd (runStateT m s)

bracketOnError :: MonadMask m => m a -> (a -> m b) -> (a -> m c) -> m c #

Async safe version of bracketOnError