preql-0.5: safe PostgreSQL queries using Quasiquoters
Safe HaskellNone
LanguageHaskell2010

Preql.Imports

Description

Common imports, so I don't need to repeat them everywhere

Synopsis

Documentation

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.

'join bss' can be understood as the do expression

do bs <- bss
   bs

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 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:

Left identity
return a >>= k = k a
Right identity
m >>= return = m
Associativity
m >>= (\x -> k x >>= h) = (m >>= k) >>= h

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

The above laws imply:

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.

'as >>= bs' can be understood as the do expression

do a <- as
   bs a

(>>) :: 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.

'as >> bs' can be understood as the do expression

do as
   bs

return :: a -> m a #

Inject a value into the monadic type.

Instances

Instances details
Monad []

Since: base-2.1

Instance details

Defined in GHC.Base

Methods

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

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

return :: a -> [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 #

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 #

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 #

Monad Q 
Instance details

Defined in Language.Haskell.TH.Syntax

Methods

(>>=) :: Q a -> (a -> Q b) -> Q b #

(>>) :: Q a -> Q b -> Q b #

return :: a -> Q a #

Monad IResult 
Instance details

Defined in Data.Aeson.Types.Internal

Methods

(>>=) :: IResult a -> (a -> IResult b) -> IResult b #

(>>) :: IResult a -> IResult b -> IResult b #

return :: a -> IResult a #

Monad Result 
Instance details

Defined in Data.Aeson.Types.Internal

Methods

(>>=) :: Result a -> (a -> Result b) -> Result b #

(>>) :: Result a -> Result b -> Result b #

return :: a -> Result a #

Monad Parser 
Instance details

Defined in Data.Aeson.Types.Internal

Methods

(>>=) :: Parser a -> (a -> Parser b) -> Parser b #

(>>) :: Parser a -> Parser b -> Parser b #

return :: a -> Parser a #

Monad Complex

Since: base-4.9.0.0

Instance details

Defined in Data.Complex

Methods

(>>=) :: Complex a -> (a -> Complex b) -> Complex b #

(>>) :: Complex a -> Complex b -> Complex b #

return :: a -> Complex 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 #

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 #

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 #

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 #

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 #

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 #

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 #

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 #

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 #

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 #

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 #

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 #

Monad ReadPrec

Since: base-2.1

Instance details

Defined in Text.ParserCombinators.ReadPrec

Methods

(>>=) :: ReadPrec a -> (a -> ReadPrec b) -> ReadPrec b #

(>>) :: ReadPrec a -> ReadPrec b -> ReadPrec b #

return :: a -> ReadPrec 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 #

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 #

Monad PutM 
Instance details

Defined in Data.Binary.Put

Methods

(>>=) :: PutM a -> (a -> PutM b) -> PutM b #

(>>) :: PutM a -> PutM b -> PutM b #

return :: a -> PutM a #

Monad Get 
Instance details

Defined in Data.Binary.Get.Internal

Methods

(>>=) :: Get a -> (a -> Get b) -> Get b #

(>>) :: Get a -> Get b -> Get b #

return :: a -> Get a #

Monad BinaryParser 
Instance details

Defined in BinaryParser

Monad Put 
Instance details

Defined in Data.ByteString.Builder.Internal

Methods

(>>=) :: Put a -> (a -> Put b) -> Put b #

(>>) :: Put a -> Put b -> Put b #

return :: a -> Put a #

Monad PutM 
Instance details

Defined in Data.Serialize.Put

Methods

(>>=) :: PutM a -> (a -> PutM b) -> PutM b #

(>>) :: PutM a -> PutM b -> PutM b #

return :: a -> PutM a #

Monad Get 
Instance details

Defined in Data.Serialize.Get

Methods

(>>=) :: Get a -> (a -> Get b) -> Get b #

(>>) :: Get a -> Get b -> Get b #

return :: a -> Get a #

Monad Tree 
Instance details

Defined in Data.Tree

Methods

(>>=) :: Tree a -> (a -> Tree b) -> Tree b #

(>>) :: Tree a -> Tree b -> Tree b #

return :: a -> Tree 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 #

Monad BinaryDeserializer 
Instance details

Defined in Data.Deserializer

Monad CerealDeserializer 
Instance details

Defined in Data.Deserializer

Monad DNonEmpty 
Instance details

Defined in Data.DList.DNonEmpty.Internal

Methods

(>>=) :: DNonEmpty a -> (a -> DNonEmpty b) -> DNonEmpty b #

(>>) :: DNonEmpty a -> DNonEmpty b -> DNonEmpty b #

return :: a -> DNonEmpty a #

Monad DList 
Instance details

Defined in Data.DList.Internal

Methods

(>>=) :: DList a -> (a -> DList b) -> DList b #

(>>) :: DList a -> DList b -> DList b #

return :: a -> DList a #

Monad Composite 
Instance details

Defined in PostgreSQL.Binary.Decoding

Methods

(>>=) :: Composite a -> (a -> Composite b) -> Composite b #

(>>) :: Composite a -> Composite b -> Composite b #

return :: a -> Composite 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 #

Monad SmallArray 
Instance details

Defined in Data.Primitive.SmallArray

Methods

(>>=) :: SmallArray a -> (a -> SmallArray b) -> SmallArray b #

(>>) :: SmallArray a -> SmallArray b -> SmallArray b #

return :: a -> SmallArray a #

Monad Array 
Instance details

Defined in Data.Primitive.Array

Methods

(>>=) :: Array a -> (a -> Array b) -> Array b #

(>>) :: Array a -> Array b -> Array b #

return :: a -> Array 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 #

Monad Alex Source # 
Instance details

Defined in Preql.QuasiQuoter.Raw.Lex

Methods

(>>=) :: Alex a -> (a -> Alex b) -> Alex b #

(>>) :: Alex a -> Alex b -> Alex b #

return :: a -> Alex a #

Monad Alex Source # 
Instance details

Defined in Preql.QuasiQuoter.Syntax.Lex

Methods

(>>=) :: Alex a -> (a -> Alex b) -> Alex b #

(>>) :: Alex a -> Alex b -> Alex b #

return :: a -> Alex a #

Monad Transaction Source # 
Instance details

Defined in Preql.Effect.Internal

Methods

(>>=) :: Transaction a -> (a -> Transaction b) -> Transaction b #

(>>) :: Transaction a -> Transaction b -> Transaction b #

return :: a -> Transaction 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 #

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 #

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) #

Representable f => Monad (Co f) 
Instance details

Defined in Data.Functor.Rep

Methods

(>>=) :: Co f a -> (a -> Co f b) -> Co f b #

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

return :: a -> Co f a #

Monad (ST s)

Since: base-2.1

Instance details

Defined in GHC.ST

Methods

(>>=) :: ST s a -> (a -> ST s b) -> ST s b #

(>>) :: ST s a -> ST s b -> ST s b #

return :: a -> ST s a #

Monad (Parser i) 
Instance details

Defined in Data.Attoparsec.Internal.Types

Methods

(>>=) :: Parser i a -> (a -> Parser i b) -> Parser i b #

(>>) :: Parser i a -> Parser i b -> Parser i b #

return :: a -> Parser i a #

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 #

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 #

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 #

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 #

Monad μ => Monad (LittleEndianDeserializer μ) 
Instance details

Defined in Data.Deserializer

Monad μ => Monad (BigEndianDeserializer μ) 
Instance details

Defined in Data.Deserializer

Alternative f => Monad (Cofree f) 
Instance details

Defined in Control.Comonad.Cofree

Methods

(>>=) :: Cofree f a -> (a -> Cofree f b) -> Cofree f b #

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

return :: a -> Cofree f a #

Semigroup a => Monad (These a) 
Instance details

Defined in Data.Strict.These

Methods

(>>=) :: These a a0 -> (a0 -> These a b) -> These a b #

(>>) :: These a a0 -> These a b -> These a b #

return :: a0 -> These a a0 #

Semigroup a => Monad (These a) 
Instance details

Defined in Data.These

Methods

(>>=) :: These a a0 -> (a0 -> These a b) -> These a b #

(>>) :: These a a0 -> These a b -> These a b #

return :: a0 -> These a a0 #

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 #

(Monoid a, Monoid b) => Monad ((,,) a b)

Since: base-4.14.0.0

Instance details

Defined in GHC.Base

Methods

(>>=) :: (a, b, a0) -> (a0 -> (a, b, b0)) -> (a, b, b0) #

(>>) :: (a, b, a0) -> (a, b, b0) -> (a, b, b0) #

return :: a0 -> (a, b, a0) #

Monad m => Monad (Kleisli m a)

Since: base-4.14.0.0

Instance details

Defined in Control.Arrow

Methods

(>>=) :: Kleisli m a a0 -> (a0 -> Kleisli m a b) -> Kleisli m a b #

(>>) :: Kleisli m a a0 -> Kleisli m a b -> Kleisli m a b #

return :: a0 -> Kleisli m a a0 #

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 #

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 #

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 #

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 #

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 #

(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 #

(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 #

Monad m => Monad (StateT s m) 
Instance details

Defined in Control.Monad.Trans.State.Lazy

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 #

Monad (Tagged s) 
Instance details

Defined in Data.Tagged

Methods

(>>=) :: Tagged s a -> (a -> Tagged s b) -> Tagged s b #

(>>) :: Tagged s a -> Tagged s b -> Tagged s b #

return :: a -> Tagged s 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 #

(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 #

(Monoid a, Monoid b, Monoid c) => Monad ((,,,) a b c)

Since: base-4.14.0.0

Instance details

Defined in GHC.Base

Methods

(>>=) :: (a, b, c, a0) -> (a0 -> (a, b, c, b0)) -> (a, b, c, b0) #

(>>) :: (a, b, c, a0) -> (a, b, c, b0) -> (a, b, c, b0) #

return :: a0 -> (a, b, c, a0) #

(Monad f, Monad g) => Monad (Product f g)

Since: base-4.9.0.0

Instance details

Defined in Data.Functor.Product

Methods

(>>=) :: Product f g a -> (a -> Product f g b) -> Product f g b #

(>>) :: Product f g a -> Product f g b -> Product f g b #

return :: a -> Product 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 #

(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 #

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 #

(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 #

(Monoid w, Monad m) => Monad (RWST r w s m) 
Instance details

Defined in Control.Monad.Trans.RWS.Lazy

Methods

(>>=) :: RWST r w s m a -> (a -> RWST r w s m b) -> RWST r w s m b #

(>>) :: RWST r w s m a -> RWST r w s m b -> RWST r w s m b #

return :: a -> RWST r w s m a #

(Monoid w, Monad m) => Monad (RWST r w s m) 
Instance details

Defined in Control.Monad.Trans.RWS.Strict

Methods

(>>=) :: RWST r w s m a -> (a -> RWST r w s m b) -> RWST r w s m b #

(>>) :: RWST r w s m a -> RWST r w s m b -> RWST r w s m b #

return :: a -> RWST r w s m a #

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

A type f is a Functor if it provides a function fmap which, given any types a and b lets you apply any function from (a -> b) to turn an f a into an f b, preserving the structure of f. Furthermore f needs to adhere to the following:

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

Note, that the second law follows from the free theorem of the type fmap and the first law, so you need only check that the former condition holds.

Minimal complete definition

fmap

Methods

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

Using ApplicativeDo: 'fmap f as' can be understood as the do expression

do a <- as
   pure (f a)

with an inferred Functor constraint.

(<$) :: 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.

Using ApplicativeDo: 'a <$ bs' can be understood as the do expression

do bs
   pure a

with an inferred Functor constraint.

Instances

Instances details
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 Q 
Instance details

Defined in Language.Haskell.TH.Syntax

Methods

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

(<$) :: a -> Q b -> Q a #

Functor Only 
Instance details

Defined in Data.Tuple.Only

Methods

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

(<$) :: a -> Only b -> Only a #

Functor FromJSONKeyFunction

Only law abiding up to interpretation

Instance details

Defined in Data.Aeson.Types.FromJSON

Functor IResult 
Instance details

Defined in Data.Aeson.Types.Internal

Methods

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

(<$) :: a -> IResult b -> IResult a #

Functor Result 
Instance details

Defined in Data.Aeson.Types.Internal

Methods

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

(<$) :: a -> Result b -> Result a #

Functor Parser 
Instance details

Defined in Data.Aeson.Types.Internal

Methods

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

(<$) :: a -> Parser b -> Parser a #

Functor Complex

Since: base-4.9.0.0

Instance details

Defined in Data.Complex

Methods

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

(<$) :: a -> Complex b -> Complex 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 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 ReadPrec

Since: base-2.1

Instance details

Defined in Text.ParserCombinators.ReadPrec

Methods

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

(<$) :: a -> ReadPrec b -> ReadPrec 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 PutM 
Instance details

Defined in Data.Binary.Put

Methods

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

(<$) :: a -> PutM b -> PutM a #

Functor Decoder 
Instance details

Defined in Data.Binary.Get.Internal

Methods

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

(<$) :: a -> Decoder b -> Decoder a #

Functor Get 
Instance details

Defined in Data.Binary.Get.Internal

Methods

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

(<$) :: a -> Get b -> Get a #

Functor BinaryParser 
Instance details

Defined in BinaryParser

Methods

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

(<$) :: a -> BinaryParser b -> BinaryParser a #

Functor Put 
Instance details

Defined in Data.ByteString.Builder.Internal

Methods

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

(<$) :: a -> Put b -> Put a #

Functor PutM 
Instance details

Defined in Data.Serialize.Put

Methods

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

(<$) :: a -> PutM b -> PutM a #

Functor Result 
Instance details

Defined in Data.Serialize.Get

Methods

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

(<$) :: a -> Result b -> Result a #

Functor Get 
Instance details

Defined in Data.Serialize.Get

Methods

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

(<$) :: a -> Get b -> Get a #

Functor IntMap 
Instance details

Defined in Data.IntMap.Internal

Methods

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

(<$) :: a -> IntMap b -> IntMap a #

Functor Tree 
Instance details

Defined in Data.Tree

Methods

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

(<$) :: a -> Tree b -> Tree 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 BinaryDeserializer 
Instance details

Defined in Data.Deserializer

Functor CerealDeserializer 
Instance details

Defined in Data.Deserializer

Functor DNonEmpty 
Instance details

Defined in Data.DList.DNonEmpty.Internal

Methods

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

(<$) :: a -> DNonEmpty b -> DNonEmpty a #

Functor DList 
Instance details

Defined in Data.DList.Internal

Methods

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

(<$) :: a -> DList b -> DList a #

Functor InetAddr 
Instance details

Defined in Network.IP.Addr

Methods

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

(<$) :: a -> InetAddr b -> InetAddr a #

Functor Composite 
Instance details

Defined in PostgreSQL.Binary.Decoding

Methods

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

(<$) :: a -> Composite b -> Composite a #

Functor Array 
Instance details

Defined in PostgreSQL.Binary.Decoding

Methods

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

(<$) :: a -> Array b -> Array a #

Functor Vector 
Instance details

Defined in Data.Vector

Methods

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

(<$) :: a -> Vector b -> Vector a #

Functor Doc 
Instance details

Defined in Text.PrettyPrint.Annotated.HughesPJ

Methods

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

(<$) :: a -> Doc b -> Doc a #

Functor AnnotDetails 
Instance details

Defined in Text.PrettyPrint.Annotated.HughesPJ

Methods

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

(<$) :: a -> AnnotDetails b -> AnnotDetails a #

Functor Span 
Instance details

Defined in Text.PrettyPrint.Annotated.HughesPJ

Methods

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

(<$) :: a -> Span b -> Span a #

Functor SmallArray 
Instance details

Defined in Data.Primitive.SmallArray

Methods

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

(<$) :: a -> SmallArray b -> SmallArray a #

Functor Array 
Instance details

Defined in Data.Primitive.Array

Methods

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

(<$) :: a -> Array b -> Array a #

Functor Maybe 
Instance details

Defined in Data.Strict.Maybe

Methods

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

(<$) :: a -> Maybe b -> Maybe 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 Alex Source # 
Instance details

Defined in Preql.QuasiQuoter.Raw.Lex

Methods

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

(<$) :: a -> Alex b -> Alex a #

Functor Alex Source # 
Instance details

Defined in Preql.QuasiQuoter.Syntax.Lex

Methods

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

(<$) :: a -> Alex b -> Alex a #

Functor FieldDecoder Source # 
Instance details

Defined in Preql.FromSql.Class

Methods

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

(<$) :: a -> FieldDecoder b -> FieldDecoder a #

Functor Transaction Source # 
Instance details

Defined in Preql.Effect.Internal

Methods

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

(<$) :: a -> Transaction b -> Transaction 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 f => Functor (Co f) 
Instance details

Defined in Data.Functor.Rep

Methods

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

(<$) :: a -> Co f b -> Co f a #

Functor (HashMap k) 
Instance details

Defined in Data.HashMap.Internal

Methods

fmap :: (a -> b) -> HashMap k a -> HashMap k b #

(<$) :: a -> HashMap k b -> HashMap k 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 (ST s)

Since: base-2.1

Instance details

Defined in GHC.ST

Methods

fmap :: (a -> b) -> ST s a -> ST s b #

(<$) :: a -> ST s b -> ST s a #

Functor (Array i)

Since: base-2.1

Instance details

Defined in GHC.Arr

Methods

fmap :: (a -> b) -> Array i a -> Array i b #

(<$) :: a -> Array i b -> Array i a #

Functor (IResult i) 
Instance details

Defined in Data.Attoparsec.Internal.Types

Methods

fmap :: (a -> b) -> IResult i a -> IResult i b #

(<$) :: a -> IResult i b -> IResult i a #

Functor (Parser i) 
Instance details

Defined in Data.Attoparsec.Internal.Types

Methods

fmap :: (a -> b) -> Parser i a -> Parser i b #

(<$) :: a -> Parser i b -> Parser i a #

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 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 #

Functor μ => Functor (LittleEndianDeserializer μ) 
Instance details

Defined in Data.Deserializer

Functor μ => Functor (BigEndianDeserializer μ) 
Instance details

Defined in Data.Deserializer

Functor f => Functor (Cofree f) 
Instance details

Defined in Control.Comonad.Cofree

Methods

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

(<$) :: a -> Cofree f b -> Cofree f a #

Functor (Pair e) 
Instance details

Defined in Data.Strict.Tuple

Methods

fmap :: (a -> b) -> Pair e a -> Pair e b #

(<$) :: a -> Pair e b -> Pair e a #

Functor (These a) 
Instance details

Defined in Data.Strict.These

Methods

fmap :: (a0 -> b) -> These a a0 -> These a b #

(<$) :: a0 -> These a b -> These a a0 #

Functor (Either a) 
Instance details

Defined in Data.Strict.Either

Methods

fmap :: (a0 -> b) -> Either a a0 -> Either a b #

(<$) :: a0 -> Either a b -> Either a a0 #

Functor (These a) 
Instance details

Defined in Data.These

Methods

fmap :: (a0 -> b) -> These a a0 -> These a b #

(<$) :: a0 -> These a b -> These a a0 #

Functor (RowDecoder n) Source # 
Instance details

Defined in Preql.Wire.Internal

Methods

fmap :: (a -> b) -> RowDecoder n a -> RowDecoder n b #

(<$) :: a -> RowDecoder n b -> RowDecoder n 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 #

Functor ((,,) a b)

Since: base-4.14.0.0

Instance details

Defined in GHC.Base

Methods

fmap :: (a0 -> b0) -> (a, b, a0) -> (a, b, b0) #

(<$) :: a0 -> (a, b, b0) -> (a, b, a0) #

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 m => Functor (Kleisli m a)

Since: base-4.14.0.0

Instance details

Defined in Control.Arrow

Methods

fmap :: (a0 -> b) -> Kleisli m a a0 -> Kleisli m a b #

(<$) :: a0 -> Kleisli m a b -> Kleisli m a 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 #

Bifunctor p => Functor (Join p) 
Instance details

Defined in Data.Bifunctor.Join

Methods

fmap :: (a -> b) -> Join p a -> Join p b #

(<$) :: a -> Join p b -> Join p 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 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 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 #

(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 (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.Lazy

Methods

fmap :: (a -> b) -> StateT s m a -> StateT s m b #

(<$) :: a -> StateT s m b -> StateT s m a #

Functor (Tagged s) 
Instance details

Defined in Data.Tagged

Methods

fmap :: (a -> b) -> Tagged s a -> Tagged s b #

(<$) :: a -> Tagged s b -> Tagged s a #

(Functor f, Functor g) => Functor (These1 f g) 
Instance details

Defined in Data.Functor.These

Methods

fmap :: (a -> b) -> These1 f g a -> These1 f g b #

(<$) :: a -> These1 f g b -> These1 f g a #

Functor v => Functor (Vector v n) 
Instance details

Defined in Data.Vector.Generic.Sized.Internal

Methods

fmap :: (a -> b) -> Vector v n a -> Vector v n b #

(<$) :: a -> Vector v n b -> Vector v n 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 ((,,,) a b c)

Since: base-4.14.0.0

Instance details

Defined in GHC.Base

Methods

fmap :: (a0 -> b0) -> (a, b, c, a0) -> (a, b, c, b0) #

(<$) :: a0 -> (a, b, c, b0) -> (a, b, c, a0) #

(Functor f, Functor g) => Functor (Product f g)

Since: base-4.9.0.0

Instance details

Defined in Data.Functor.Product

Methods

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

(<$) :: a -> Product f g b -> Product f g a #

(Functor f, Functor g) => Functor (Sum f g)

Since: base-4.9.0.0

Instance details

Defined in Data.Functor.Sum

Methods

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

(<$) :: a -> Sum f g b -> Sum 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 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 #

Bifunctor p => Functor (WrappedBifunctor p a) 
Instance details

Defined in Data.Bifunctor.Wrapped

Methods

fmap :: (a0 -> b) -> WrappedBifunctor p a a0 -> WrappedBifunctor p a b #

(<$) :: a0 -> WrappedBifunctor p a b -> WrappedBifunctor p a a0 #

Functor g => Functor (Joker g a) 
Instance details

Defined in Data.Bifunctor.Joker

Methods

fmap :: (a0 -> b) -> Joker g a a0 -> Joker g a b #

(<$) :: a0 -> Joker g a b -> Joker g a a0 #

Bifunctor p => Functor (Flip p a) 
Instance details

Defined in Data.Bifunctor.Flip

Methods

fmap :: (a0 -> b) -> Flip p a a0 -> Flip p a b #

(<$) :: a0 -> Flip p a b -> Flip p a a0 #

Functor (Clown f a :: Type -> Type) 
Instance details

Defined in Data.Bifunctor.Clown

Methods

fmap :: (a0 -> b) -> Clown f a a0 -> Clown f a b #

(<$) :: a0 -> Clown f a b -> Clown f a a0 #

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 #

Functor m => Functor (RWST r w s m) 
Instance details

Defined in Control.Monad.Trans.RWS.Lazy

Methods

fmap :: (a -> b) -> RWST r w s m a -> RWST r w s m b #

(<$) :: a -> RWST r w s m b -> RWST r w s m a #

Functor m => Functor (RWST r w s m) 
Instance details

Defined in Control.Monad.Trans.RWS.Strict

Methods

fmap :: (a -> b) -> RWST r w s m a -> RWST r w s m b #

(<$) :: a -> RWST r w s m b -> RWST r w s m a #

(Functor f, Bifunctor p) => Functor (Tannen f p a) 
Instance details

Defined in Data.Bifunctor.Tannen

Methods

fmap :: (a0 -> b) -> Tannen f p a a0 -> Tannen f p a b #

(<$) :: a0 -> Tannen f p a b -> Tannen f p a a0 #

(Bifunctor p, Functor g) => Functor (Biff p f g a) 
Instance details

Defined in Data.Bifunctor.Biff

Methods

fmap :: (a0 -> b) -> Biff p f g a a0 -> Biff p f g a b #

(<$) :: a0 -> Biff p f g a b -> Biff p f g a a0 #

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

Instances details
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 Q 
Instance details

Defined in Language.Haskell.TH.Syntax

Methods

fail :: String -> Q a #

MonadFail IResult 
Instance details

Defined in Data.Aeson.Types.Internal

Methods

fail :: String -> IResult a #

MonadFail Result 
Instance details

Defined in Data.Aeson.Types.Internal

Methods

fail :: String -> Result a #

MonadFail Parser 
Instance details

Defined in Data.Aeson.Types.Internal

Methods

fail :: String -> Parser a #

MonadFail ReadPrec

Since: base-4.9.0.0

Instance details

Defined in Text.ParserCombinators.ReadPrec

Methods

fail :: String -> ReadPrec a #

MonadFail ReadP

Since: base-4.9.0.0

Instance details

Defined in Text.ParserCombinators.ReadP

Methods

fail :: String -> ReadP a #

MonadFail Get 
Instance details

Defined in Data.Binary.Get.Internal

Methods

fail :: String -> Get a #

MonadFail BinaryParser 
Instance details

Defined in BinaryParser

Methods

fail :: String -> BinaryParser a #

MonadFail Get 
Instance details

Defined in Data.Serialize.Get

Methods

fail :: String -> Get a #

MonadFail DList 
Instance details

Defined in Data.DList.Internal

Methods

fail :: String -> DList a #

MonadFail Composite 
Instance details

Defined in PostgreSQL.Binary.Decoding

Methods

fail :: String -> Composite a #

MonadFail Vector

Since: vector-0.12.1.0

Instance details

Defined in Data.Vector

Methods

fail :: String -> Vector a #

MonadFail SmallArray 
Instance details

Defined in Data.Primitive.SmallArray

Methods

fail :: String -> SmallArray a #

MonadFail Array 
Instance details

Defined in Data.Primitive.Array

Methods

fail :: String -> Array a #

MonadFail P

Since: base-4.9.0.0

Instance details

Defined in Text.ParserCombinators.ReadP

Methods

fail :: String -> P a #

MonadFail Alex Source # 
Instance details

Defined in Preql.QuasiQuoter.Syntax.Lex

Methods

fail :: String -> Alex a #

MonadFail (ST s)

Since: base-4.11.0.0

Instance details

Defined in GHC.ST

Methods

fail :: String -> ST s a #

MonadFail (Parser i) 
Instance details

Defined in Data.Attoparsec.Internal.Types

Methods

fail :: String -> Parser i 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 (StateT s m) 
Instance details

Defined in Control.Monad.Trans.State.Strict

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 #

MonadFail m => MonadFail (ExceptT e m) 
Instance details

Defined in Control.Monad.Trans.Except

Methods

fail :: String -> ExceptT e 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.Lazy

Methods

fail :: String -> StateT s m a #

(Monoid w, MonadFail m) => MonadFail (RWST r w s m) 
Instance details

Defined in Control.Monad.Trans.RWS.Lazy

Methods

fail :: String -> RWST r w s m a #

(Monoid w, MonadFail m) => MonadFail (RWST r w s m) 
Instance details

Defined in Control.Monad.Trans.RWS.Strict

Methods

fail :: String -> RWST r w s m a #

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:

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

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

(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.

Using ApplicativeDo: 'fs <*> as' can be understood as the do expression

do f <- fs
   a <- as
   pure (f a)

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 <*>.

This became a typeclass method in 4.10.0.0. Prior to that, it was a function defined in terms of <*> and fmap.

Using ApplicativeDo: 'liftA2 f as bs' can be understood as the do expression

do a <- as
   b <- bs
   pure (f a b)

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

Sequence actions, discarding the value of the first argument.

'as *> bs' can be understood as the do expression

do as
   bs

This is a tad complicated for our ApplicativeDo extension which will give it a Monad constraint. For an Applicative constraint we write it of the form

do _ <- as
   b <- bs
   pure b

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

Sequence actions, discarding the value of the second argument.

Using ApplicativeDo: 'as <* bs' can be understood as the do expression

do a <- as
   bs
   pure a

Instances

Instances details
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 Q 
Instance details

Defined in Language.Haskell.TH.Syntax

Methods

pure :: a -> Q a #

(<*>) :: Q (a -> b) -> Q a -> Q b #

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

(*>) :: Q a -> Q b -> Q b #

(<*) :: Q a -> Q b -> Q a #

Applicative IResult 
Instance details

Defined in Data.Aeson.Types.Internal

Methods

pure :: a -> IResult a #

(<*>) :: IResult (a -> b) -> IResult a -> IResult b #

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

(*>) :: IResult a -> IResult b -> IResult b #

(<*) :: IResult a -> IResult b -> IResult a #

Applicative Result 
Instance details

Defined in Data.Aeson.Types.Internal

Methods

pure :: a -> Result a #

(<*>) :: Result (a -> b) -> Result a -> Result b #

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

(*>) :: Result a -> Result b -> Result b #

(<*) :: Result a -> Result b -> Result a #

Applicative Parser 
Instance details

Defined in Data.Aeson.Types.Internal

Methods

pure :: a -> Parser a #

(<*>) :: Parser (a -> b) -> Parser a -> Parser b #

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

(*>) :: Parser a -> Parser b -> Parser b #

(<*) :: Parser a -> Parser b -> Parser a #

Applicative Complex

Since: base-4.9.0.0

Instance details

Defined in Data.Complex

Methods

pure :: a -> Complex a #

(<*>) :: Complex (a -> b) -> Complex a -> Complex b #

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

(*>) :: Complex a -> Complex b -> Complex b #

(<*) :: Complex a -> Complex b -> Complex 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 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 ReadPrec

Since: base-4.6.0.0

Instance details

Defined in Text.ParserCombinators.ReadPrec

Methods

pure :: a -> ReadPrec a #

(<*>) :: ReadPrec (a -> b) -> ReadPrec a -> ReadPrec b #

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

(*>) :: ReadPrec a -> ReadPrec b -> ReadPrec b #

(<*) :: ReadPrec a -> ReadPrec b -> ReadPrec 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 PutM 
Instance details

Defined in Data.Binary.Put

Methods

pure :: a -> PutM a #

(<*>) :: PutM (a -> b) -> PutM a -> PutM b #

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

(*>) :: PutM a -> PutM b -> PutM b #

(<*) :: PutM a -> PutM b -> PutM a #

Applicative Get 
Instance details

Defined in Data.Binary.Get.Internal

Methods

pure :: a -> Get a #

(<*>) :: Get (a -> b) -> Get a -> Get b #

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

(*>) :: Get a -> Get b -> Get b #

(<*) :: Get a -> Get b -> Get a #

Applicative BinaryParser 
Instance details

Defined in BinaryParser

Applicative Put 
Instance details

Defined in Data.ByteString.Builder.Internal

Methods

pure :: a -> Put a #

(<*>) :: Put (a -> b) -> Put a -> Put b #

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

(*>) :: Put a -> Put b -> Put b #

(<*) :: Put a -> Put b -> Put a #

Applicative PutM 
Instance details

Defined in Data.Serialize.Put

Methods

pure :: a -> PutM a #

(<*>) :: PutM (a -> b) -> PutM a -> PutM b #

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

(*>) :: PutM a -> PutM b -> PutM b #

(<*) :: PutM a -> PutM b -> PutM a #

Applicative Get 
Instance details

Defined in Data.Serialize.Get

Methods

pure :: a -> Get a #

(<*>) :: Get (a -> b) -> Get a -> Get b #

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

(*>) :: Get a -> Get b -> Get b #

(<*) :: Get a -> Get b -> Get a #

Applicative Tree 
Instance details

Defined in Data.Tree

Methods

pure :: a -> Tree a #

(<*>) :: Tree (a -> b) -> Tree a -> Tree b #

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

(*>) :: Tree a -> Tree b -> Tree b #

(<*) :: Tree a -> Tree b -> Tree 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 BinaryDeserializer 
Instance details

Defined in Data.Deserializer

Applicative CerealDeserializer 
Instance details

Defined in Data.Deserializer

Applicative DNonEmpty 
Instance details

Defined in Data.DList.DNonEmpty.Internal

Methods

pure :: a -> DNonEmpty a #

(<*>) :: DNonEmpty (a -> b) -> DNonEmpty a -> DNonEmpty b #

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

(*>) :: DNonEmpty a -> DNonEmpty b -> DNonEmpty b #

(<*) :: DNonEmpty a -> DNonEmpty b -> DNonEmpty a #

Applicative DList 
Instance details

Defined in Data.DList.Internal

Methods

pure :: a -> DList a #

(<*>) :: DList (a -> b) -> DList a -> DList b #

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

(*>) :: DList a -> DList b -> DList b #

(<*) :: DList a -> DList b -> DList a #

Applicative Composite 
Instance details

Defined in PostgreSQL.Binary.Decoding

Methods

pure :: a -> Composite a #

(<*>) :: Composite (a -> b) -> Composite a -> Composite b #

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

(*>) :: Composite a -> Composite b -> Composite b #

(<*) :: Composite a -> Composite b -> Composite 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 SmallArray 
Instance details

Defined in Data.Primitive.SmallArray

Methods

pure :: a -> SmallArray a #

(<*>) :: SmallArray (a -> b) -> SmallArray a -> SmallArray b #

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

(*>) :: SmallArray a -> SmallArray b -> SmallArray b #

(<*) :: SmallArray a -> SmallArray b -> SmallArray a #

Applicative Array 
Instance details

Defined in Data.Primitive.Array

Methods

pure :: a -> Array a #

(<*>) :: Array (a -> b) -> Array a -> Array b #

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

(*>) :: Array a -> Array b -> Array b #

(<*) :: Array a -> Array b -> Array 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 Alex Source # 
Instance details

Defined in Preql.QuasiQuoter.Raw.Lex

Methods

pure :: a -> Alex a #

(<*>) :: Alex (a -> b) -> Alex a -> Alex b #

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

(*>) :: Alex a -> Alex b -> Alex b #

(<*) :: Alex a -> Alex b -> Alex a #

Applicative Alex Source # 
Instance details

Defined in Preql.QuasiQuoter.Syntax.Lex

Methods

pure :: a -> Alex a #

(<*>) :: Alex (a -> b) -> Alex a -> Alex b #

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

(*>) :: Alex a -> Alex b -> Alex b #

(<*) :: Alex a -> Alex b -> Alex a #

Applicative Transaction Source # 
Instance details

Defined in Preql.Effect.Internal

Methods

pure :: a -> Transaction a #

(<*>) :: Transaction (a -> b) -> Transaction a -> Transaction b #

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

(*>) :: Transaction a -> Transaction b -> Transaction b #

(<*) :: Transaction a -> Transaction b -> Transaction 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, Strings 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) #

Representable f => Applicative (Co f) 
Instance details

Defined in Data.Functor.Rep

Methods

pure :: a -> Co f a #

(<*>) :: Co f (a -> b) -> Co f a -> Co f b #

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

(*>) :: Co f a -> Co f b -> Co f b #

(<*) :: Co f a -> Co f b -> Co f a #

Applicative (ST s)

Since: base-4.4.0.0

Instance details

Defined in GHC.ST

Methods

pure :: a -> ST s a #

(<*>) :: ST s (a -> b) -> ST s a -> ST s b #

liftA2 :: (a -> b -> c) -> ST s a -> ST s b -> ST s c #

(*>) :: ST s a -> ST s b -> ST s b #

(<*) :: ST s a -> ST s b -> ST s a #

Applicative (Parser i) 
Instance details

Defined in Data.Attoparsec.Internal.Types

Methods

pure :: a -> Parser i a #

(<*>) :: Parser i (a -> b) -> Parser i a -> Parser i b #

liftA2 :: (a -> b -> c) -> Parser i a -> Parser i b -> Parser i c #

(*>) :: Parser i a -> Parser i b -> Parser i b #

(<*) :: Parser i a -> Parser i b -> Parser i a #

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 μ => Applicative (LittleEndianDeserializer μ) 
Instance details

Defined in Data.Deserializer

Applicative μ => Applicative (BigEndianDeserializer μ) 
Instance details

Defined in Data.Deserializer

Alternative f => Applicative (Cofree f) 
Instance details

Defined in Control.Comonad.Cofree

Methods

pure :: a -> Cofree f a #

(<*>) :: Cofree f (a -> b) -> Cofree f a -> Cofree f b #

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

(*>) :: Cofree f a -> Cofree f b -> Cofree f b #

(<*) :: Cofree f a -> Cofree f b -> Cofree f a #

Semigroup a => Applicative (These a) 
Instance details

Defined in Data.Strict.These

Methods

pure :: a0 -> These a a0 #

(<*>) :: These a (a0 -> b) -> These a a0 -> These a b #

liftA2 :: (a0 -> b -> c) -> These a a0 -> These a b -> These a c #

(*>) :: These a a0 -> These a b -> These a b #

(<*) :: These a a0 -> These a b -> These a a0 #

Semigroup a => Applicative (These a) 
Instance details

Defined in Data.These

Methods

pure :: a0 -> These a a0 #

(<*>) :: These a (a0 -> b) -> These a a0 -> These a b #

liftA2 :: (a0 -> b -> c) -> These a a0 -> These a b -> These a c #

(*>) :: These a a0 -> These a b -> These a b #

(<*) :: These a a0 -> These a b -> These a a0 #

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 #

(Monoid a, Monoid b) => Applicative ((,,) a b)

Since: base-4.14.0.0

Instance details

Defined in GHC.Base

Methods

pure :: a0 -> (a, b, a0) #

(<*>) :: (a, b, a0 -> b0) -> (a, b, a0) -> (a, b, b0) #

liftA2 :: (a0 -> b0 -> c) -> (a, b, a0) -> (a, b, b0) -> (a, b, c) #

(*>) :: (a, b, a0) -> (a, b, b0) -> (a, b, b0) #

(<*) :: (a, b, a0) -> (a, b, b0) -> (a, b, a0) #

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 #

Applicative m => Applicative (Kleisli m a)

Since: base-4.14.0.0

Instance details

Defined in Control.Arrow

Methods

pure :: a0 -> Kleisli m a a0 #

(<*>) :: Kleisli m a (a0 -> b) -> Kleisli m a a0 -> Kleisli m a b #

liftA2 :: (a0 -> b -> c) -> Kleisli m a a0 -> Kleisli m a b -> Kleisli m a c #

(*>) :: Kleisli m a a0 -> Kleisli m a b -> Kleisli m a b #

(<*) :: Kleisli m a a0 -> Kleisli m a b -> Kleisli m a 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 #

Biapplicative p => Applicative (Join p) 
Instance details

Defined in Data.Bifunctor.Join

Methods

pure :: a -> Join p a #

(<*>) :: Join p (a -> b) -> Join p a -> Join p b #

liftA2 :: (a -> b -> c) -> Join p a -> Join p b -> Join p c #

(*>) :: Join p a -> Join p b -> Join p b #

(<*) :: Join p a -> Join p b -> Join p 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 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 #

(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 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 (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.Lazy

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 (Tagged s) 
Instance details

Defined in Data.Tagged

Methods

pure :: a -> Tagged s a #

(<*>) :: Tagged s (a -> b) -> Tagged s a -> Tagged s b #

liftA2 :: (a -> b -> c) -> Tagged s a -> Tagged s b -> Tagged s c #

(*>) :: Tagged s a -> Tagged s b -> Tagged s b #

(<*) :: Tagged s a -> Tagged s b -> Tagged s a #

Applicative ((->) r :: Type -> Type)

Since: base-2.1

Instance details

Defined in GHC.Base

Methods

pure :: a -> r -> a #

(<*>) :: (r -> (a -> b)) -> (r -> a) -> r -> b #

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

(*>) :: (r -> a) -> (r -> b) -> r -> b #

(<*) :: (r -> a) -> (r -> b) -> r -> a #

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 #

(Monoid a, Monoid b, Monoid c) => Applicative ((,,,) a b c)

Since: base-4.14.0.0

Instance details

Defined in GHC.Base

Methods

pure :: a0 -> (a, b, c, a0) #

(<*>) :: (a, b, c, a0 -> b0) -> (a, b, c, a0) -> (a, b, c, b0) #

liftA2 :: (a0 -> b0 -> c0) -> (a, b, c, a0) -> (a, b, c, b0) -> (a, b, c, c0) #

(*>) :: (a, b, c, a0) -> (a, b, c, b0) -> (a, b, c, b0) #

(<*) :: (a, b, c, a0) -> (a, b, c, b0) -> (a, b, c, a0) #

(Applicative f, Applicative g) => Applicative (Product f g)

Since: base-4.9.0.0

Instance details

Defined in Data.Functor.Product

Methods

pure :: a -> Product f g a #

(<*>) :: Product f g (a -> b) -> Product f g a -> Product f g b #

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

(*>) :: Product f g a -> Product f g b -> Product f g b #

(<*) :: Product f g a -> Product f g b -> Product 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 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 #

(Monoid w, Functor m, Monad m) => Applicative (RWST r w s m) 
Instance details

Defined in Control.Monad.Trans.RWS.Lazy

Methods

pure :: a -> RWST r w s m a #

(<*>) :: RWST r w s m (a -> b) -> RWST r w s m a -> RWST r w s m b #

liftA2 :: (a -> b -> c) -> RWST r w s m a -> RWST r w s m b -> RWST r w s m c #

(*>) :: RWST r w s m a -> RWST r w s m b -> RWST r w s m b #

(<*) :: RWST r w s m a -> RWST r w s m b -> RWST r w s m a #

(Monoid w, Functor m, Monad m) => Applicative (RWST r w s m) 
Instance details

Defined in Control.Monad.Trans.RWS.Strict

Methods

pure :: a -> RWST r w s m a #

(<*>) :: RWST r w s m (a -> b) -> RWST r w s m a -> RWST r w s m b #

liftA2 :: (a -> b -> c) -> RWST r w s m a -> RWST r w s m b -> RWST r w s m c #

(*>) :: RWST r w s m a -> RWST r w s m b -> RWST r w s m b #

(<*) :: RWST r w s m a -> RWST r w s m b -> RWST r w s m a #

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

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

Methods

fold :: Monoid m => t m -> m #

Combine the elements of a structure using a monoid.

foldMap :: Monoid m => (a -> m) -> t a -> m #

Map each element of the structure to a monoid, and combine the results.

foldMap' :: Monoid m => (a -> m) -> t a -> m #

A variant of foldMap that is strict in the accumulator.

Since: base-4.13.0.0

foldr :: (a -> b -> b) -> b -> t a -> b #

Right-associative fold of a structure.

In the case of lists, foldr, when applied to a binary operator, a starting value (typically the right-identity of the operator), and a list, reduces the list using the binary operator, from right to left:

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

Note that, since the head of the resulting expression is produced by an application of the operator to the first element of the list, foldr can produce a terminating expression from an infinite list.

For a general Foldable structure this should be semantically identical to,

foldr f z = foldr f z . toList

foldr' :: (a -> b -> b) -> b -> t a -> b #

Right-associative fold of a structure, but with strict application of the operator.

Since: base-4.6.0.0

foldl :: (b -> a -> b) -> b -> t a -> b #

Left-associative fold of a structure.

In the case of lists, foldl, when applied to a binary operator, a starting value (typically the left-identity of the operator), and a list, reduces the list using the binary operator, from left to right:

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

Note that to produce the outermost application of the operator the entire input list must be traversed. This means that foldl' will diverge if given an infinite list.

Also note that if you want an efficient left-fold, you probably want to use foldl' instead of foldl. The reason for this is that latter does not force the "inner" results (e.g. z `f` x1 in the above example) before applying them to the operator (e.g. to (`f` x2)). This results in a thunk chain \(\mathcal{O}(n)\) elements long, which then must be evaluated from the outside-in.

For a general Foldable structure this should be semantically identical to,

foldl f z = foldl f z . toList

foldl' :: (b -> a -> b) -> b -> t a -> b #

Left-associative fold of a structure but with strict application of the operator.

This ensures that each step of the fold is forced to weak head normal form before being applied, avoiding the collection of thunks that would otherwise occur. This is often what you want to strictly reduce a finite list to a single, monolithic result (e.g. length).

For a general Foldable structure this should be semantically identical to,

foldl' f z = foldl' f z . toList

Since: base-4.6.0.0

foldr1 :: (a -> a -> a) -> t a -> a #

A variant of foldr that has no base case, and thus may only be applied to non-empty structures.

foldr1 f = foldr1 f . toList

foldl1 :: (a -> a -> a) -> t a -> a #

A variant of foldl that has no base case, and thus may only be applied to non-empty structures.

foldl1 f = foldl1 f . toList

toList :: t a -> [a] #

List of elements of a structure, from left to right.

Since: base-4.8.0.0

null :: t a -> Bool #

Test whether the structure is empty. The default implementation is optimized for structures that are similar to cons-lists, because there is no general way to do better.

Since: base-4.8.0.0

length :: t a -> Int #

Returns the size/length of a finite structure as an Int. The default implementation is optimized for structures that are similar to cons-lists, because there is no general way to do better.

Since: base-4.8.0.0

elem :: Eq a => a -> t a -> Bool infix 4 #

Does the element occur in the structure?

Since: base-4.8.0.0

maximum :: Ord a => t a -> a #

The largest element of a non-empty structure.

Since: base-4.8.0.0

minimum :: Ord a => t a -> a #

The least element of a non-empty structure.

Since: base-4.8.0.0

sum :: Num a => t a -> a #

The sum function computes the sum of the numbers of a structure.

Since: base-4.8.0.0

product :: Num a => t a -> a #

The product function computes the product of the numbers of a structure.

Since: base-4.8.0.0

Instances

Instances details
Foldable []

Since: base-2.1

Instance details

Defined in Data.Foldable

Methods

fold :: Monoid m => [m] -> m #

foldMap :: Monoid m => (a -> m) -> [a] -> 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 #

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 #

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 IResult 
Instance details

Defined in Data.Aeson.Types.Internal

Methods

fold :: Monoid m => IResult m -> m #

foldMap :: Monoid m => (a -> m) -> IResult a -> m #

foldMap' :: Monoid m => (a -> m) -> IResult a -> m #

foldr :: (a -> b -> b) -> b -> IResult a -> b #

foldr' :: (a -> b -> b) -> b -> IResult a -> b #

foldl :: (b -> a -> b) -> b -> IResult a -> b #

foldl' :: (b -> a -> b) -> b -> IResult a -> b #

foldr1 :: (a -> a -> a) -> IResult a -> a #

foldl1 :: (a -> a -> a) -> IResult a -> a #

toList :: IResult a -> [a] #

null :: IResult a -> Bool #

length :: IResult a -> Int #

elem :: Eq a => a -> IResult a -> Bool #

maximum :: Ord a => IResult a -> a #

minimum :: Ord a => IResult a -> a #

sum :: Num a => IResult a -> a #

product :: Num a => IResult a -> a #

Foldable Result 
Instance details

Defined in Data.Aeson.Types.Internal

Methods

fold :: Monoid m => Result m -> m #

foldMap :: Monoid m => (a -> m) -> Result a -> m #

foldMap' :: Monoid m => (a -> m) -> Result a -> m #

foldr :: (a -> b -> b) -> b -> Result a -> b #

foldr' :: (a -> b -> b) -> b -> Result a -> b #

foldl :: (b -> a -> b) -> b -> Result a -> b #

foldl' :: (b -> a -> b) -> b -> Result a -> b #

foldr1 :: (a -> a -> a) -> Result a -> a #

foldl1 :: (a -> a -> a) -> Result a -> a #

toList :: Result a -> [a] #

null :: Result a -> Bool #

length :: Result a -> Int #

elem :: Eq a => a -> Result a -> Bool #

maximum :: Ord a => Result a -> a #

minimum :: Ord a => Result a -> a #

sum :: Num a => Result a -> a #

product :: Num a => Result a -> a #

Foldable Complex

Since: base-4.9.0.0

Instance details

Defined in Data.Complex

Methods

fold :: Monoid m => Complex m -> m #

foldMap :: Monoid m => (a -> m) -> Complex a -> m #

foldMap' :: Monoid m => (a -> m) -> Complex a -> m #

foldr :: (a -> b -> b) -> b -> Complex a -> b #

foldr' :: (a -> b -> b) -> b -> Complex a -> b #

foldl :: (b -> a -> b) -> b -> Complex a -> b #

foldl' :: (b -> a -> b) -> b -> Complex a -> b #

foldr1 :: (a -> a -> a) -> Complex a -> a #

foldl1 :: (a -> a -> a) -> Complex a -> a #

toList :: Complex a -> [a] #

null :: Complex a -> Bool #

length :: Complex a -> Int #

elem :: Eq a => a -> Complex a -> Bool #

maximum :: Ord a => Complex a -> a #

minimum :: Ord a => Complex a -> a #

sum :: Num a => Complex a -> a #

product :: Num a => Complex 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 #

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 #

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 #

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 #

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 #

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 #

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 #

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 #

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 #

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 #

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 #

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 #

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 #

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 #

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

Folds in order of increasing key.

Instance details

Defined in Data.IntMap.Internal

Methods

fold :: Monoid m => IntMap m -> m #

foldMap :: Monoid m => (a -> m) -> IntMap a -> 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 Tree 
Instance details

Defined in Data.Tree

Methods

fold :: Monoid m => Tree m -> m #

foldMap :: Monoid m => (a -> m) -> Tree a -> m #

foldMap' :: Monoid m => (a -> m) -> Tree a -> m #

foldr :: (a -> b -> b) -> b -> Tree a -> b #

foldr' :: (a -> b -> b) -> b -> Tree a -> b #

foldl :: (b -> a -> b) -> b -> Tree a -> b #

foldl' :: (b -> a -> b) -> b -> Tree a -> b #

foldr1 :: (a -> a -> a) -> Tree a -> a #

foldl1 :: (a -> a -> a) -> Tree a -> a #

toList :: Tree a -> [a] #

null :: Tree a -> Bool #

length :: Tree a -> Int #

elem :: Eq a => a -> Tree a -> Bool #

maximum :: Ord a => Tree a -> a #

minimum :: Ord a => Tree a -> a #

sum :: Num a => Tree a -> a #

product :: Num a => Tree 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 #

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 #

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 #

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 #

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 #

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 #

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 #

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

Folds in order of increasing key.

Instance details

Defined in Data.Set.Internal

Methods

fold :: Monoid m => Set m -> m #

foldMap :: Monoid m => (a -> m) -> Set a -> 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 DNonEmpty 
Instance details

Defined in Data.DList.DNonEmpty.Internal

Methods

fold :: Monoid m => DNonEmpty m -> m #

foldMap :: Monoid m => (a -> m) -> DNonEmpty a -> m #

foldMap' :: Monoid m => (a -> m) -> DNonEmpty a -> m #

foldr :: (a -> b -> b) -> b -> DNonEmpty a -> b #

foldr' :: (a -> b -> b) -> b -> DNonEmpty a -> b #

foldl :: (b -> a -> b) -> b -> DNonEmpty a -> b #

foldl' :: (b -> a -> b) -> b -> DNonEmpty a -> b #

foldr1 :: (a -> a -> a) -> DNonEmpty a -> a #

foldl1 :: (a -> a -> a) -> DNonEmpty a -> a #

toList :: DNonEmpty a -> [a] #

null :: DNonEmpty a -> Bool #

length :: DNonEmpty a -> Int #

elem :: Eq a => a -> DNonEmpty a -> Bool #

maximum :: Ord a => DNonEmpty a -> a #

minimum :: Ord a => DNonEmpty a -> a #

sum :: Num a => DNonEmpty a -> a #

product :: Num a => DNonEmpty a -> a #

Foldable DList 
Instance details

Defined in Data.DList.Internal

Methods

fold :: Monoid m => DList m -> m #

foldMap :: Monoid m => (a -> m) -> DList a -> m #

foldMap' :: Monoid m => (a -> m) -> DList a -> m #

foldr :: (a -> b -> b) -> b -> DList a -> b #

foldr' :: (a -> b -> b) -> b -> DList a -> b #

foldl :: (b -> a -> b) -> b -> DList a -> b #

foldl' :: (b -> a -> b) -> b -> DList a -> b #

foldr1 :: (a -> a -> a) -> DList a -> a #

foldl1 :: (a -> a -> a) -> DList a -> a #

toList :: DList a -> [a] #

null :: DList a -> Bool #

length :: DList a -> Int #

elem :: Eq a => a -> DList a -> Bool #

maximum :: Ord a => DList a -> a #

minimum :: Ord a => DList a -> a #

sum :: Num a => DList a -> a #

product :: Num a => DList 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 #

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 HashSet 
Instance details

Defined in Data.HashSet.Internal

Methods

fold :: Monoid m => HashSet m -> m #

foldMap :: Monoid m => (a -> m) -> HashSet a -> 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 Vector 
Instance details

Defined in Data.Vector

Methods

fold :: Monoid m => Vector m -> m #

foldMap :: Monoid m => (a -> m) -> Vector a -> 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 SmallArray 
Instance details

Defined in Data.Primitive.SmallArray

Methods

fold :: Monoid m => SmallArray m -> m #

foldMap :: Monoid m => (a -> m) -> SmallArray a -> m #

foldMap' :: Monoid m => (a -> m) -> SmallArray a -> m #

foldr :: (a -> b -> b) -> b -> SmallArray a -> b #

foldr' :: (a -> b -> b) -> b -> SmallArray a -> b #

foldl :: (b -> a -> b) -> b -> SmallArray a -> b #

foldl' :: (b -> a -> b) -> b -> SmallArray a -> b #

foldr1 :: (a -> a -> a) -> SmallArray a -> a #

foldl1 :: (a -> a -> a) -> SmallArray a -> a #

toList :: SmallArray a -> [a] #

null :: SmallArray a -> Bool #

length :: SmallArray a -> Int #

elem :: Eq a => a -> SmallArray a -> Bool #

maximum :: Ord a => SmallArray a -> a #

minimum :: Ord a => SmallArray a -> a #

sum :: Num a => SmallArray a -> a #

product :: Num a => SmallArray a -> a #

Foldable Array 
Instance details

Defined in Data.Primitive.Array

Methods

fold :: Monoid m => Array m -> m #

foldMap :: Monoid m => (a -> m) -> Array a -> m #

foldMap' :: Monoid m => (a -> m) -> Array a -> m #

foldr :: (a -> b -> b) -> b -> Array a -> b #

foldr' :: (a -> b -> b) -> b -> Array a -> b #

foldl :: (b -> a -> b) -> b -> Array a -> b #

foldl' :: (b -> a -> b) -> b -> Array a -> b #

foldr1 :: (a -> a -> a) -> Array a -> a #

foldl1 :: (a -> a -> a) -> Array a -> a #

toList :: Array a -> [a] #

null :: Array a -> Bool #

length :: Array a -> Int #

elem :: Eq a => a -> Array a -> Bool #

maximum :: Ord a => Array a -> a #

minimum :: Ord a => Array a -> a #

sum :: Num a => Array a -> a #

product :: Num a => Array a -> a #

Foldable Maybe 
Instance details

Defined in Data.Strict.Maybe

Methods

fold :: Monoid m => Maybe m -> m #

foldMap :: Monoid m => (a -> m) -> Maybe a -> 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 (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 #

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 #

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 #

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 (UAddr :: Type -> Type)

Since: base-4.9.0.0

Instance details

Defined in Data.Foldable

Methods

fold :: Monoid m => UAddr m -> m #

foldMap :: Monoid m => (a -> m) -> UAddr a -> m #

foldMap' :: Monoid m => (a -> m) -> UAddr a -> m #

foldr :: (a -> b -> b) -> b -> UAddr a -> b #

foldr' :: (a -> b -> b) -> b -> UAddr a -> b #

foldl :: (b -> a -> b) -> b -> UAddr a -> b #

foldl' :: (b -> a -> b) -> b -> UAddr a -> b #

foldr1 :: (a -> a -> a) -> UAddr a -> a #

foldl1 :: (a -> a -> a) -> UAddr a -> a #

toList :: UAddr a -> [a] #

null :: UAddr a -> Bool #

length :: UAddr a -> Int #

elem :: Eq a => a -> UAddr a -> Bool #

maximum :: Ord a => UAddr a -> a #

minimum :: Ord a => UAddr a -> a #

sum :: Num a => UAddr a -> a #

product :: Num a => UAddr a -> a #

Foldable (UChar :: Type -> Type)

Since: base-4.9.0.0

Instance details

Defined in Data.Foldable

Methods

fold :: Monoid m => UChar m -> m #

foldMap :: Monoid m => (a -> m) -> UChar a -> m #

foldMap' :: Monoid m => (a -> m) -> UChar a -> m #

foldr :: (a -> b -> b) -> b -> UChar a -> b #

foldr' :: (a -> b -> b) -> b -> UChar a -> b #

foldl :: (b -> a -> b) -> b -> UChar a -> b #

foldl' :: (b -> a -> b) -> b -> UChar a -> b #

foldr1 :: (a -> a -> a) -> UChar a -> a #

foldl1 :: (a -> a -> a) -> UChar a -> a #

toList :: UChar a -> [a] #

null :: UChar a -> Bool #

length :: UChar a -> Int #

elem :: Eq a => a -> UChar a -> Bool #

maximum :: Ord a => UChar a -> a #

minimum :: Ord a => UChar a -> a #

sum :: Num a => UChar a -> a #

product :: Num a => UChar a -> a #

Foldable (UDouble :: Type -> Type)

Since: base-4.9.0.0

Instance details

Defined in Data.Foldable

Methods

fold :: Monoid m => UDouble m -> m #

foldMap :: Monoid m => (a -> m) -> UDouble a -> m #

foldMap' :: Monoid m => (a -> m) -> UDouble a -> m #

foldr :: (a -> b -> b) -> b -> UDouble a -> b #

foldr' :: (a -> b -> b) -> b -> UDouble a -> b #

foldl :: (b -> a -> b) -> b -> UDouble a -> b #

foldl' :: (b -> a -> b) -> b -> UDouble a -> b #

foldr1 :: (a -> a -> a) -> UDouble a -> a #

foldl1 :: (a -> a -> a) -> UDouble a -> a #

toList :: UDouble a -> [a] #

null :: UDouble a -> Bool #

length :: UDouble a -> Int #

elem :: Eq a => a -> UDouble a -> Bool #

maximum :: Ord a => UDouble a -> a #

minimum :: Ord a => UDouble a -> a #

sum :: Num a => UDouble a -> a #

product :: Num a => UDouble a -> a #

Foldable (UFloat :: Type -> Type)

Since: base-4.9.0.0

Instance details

Defined in Data.Foldable

Methods

fold :: Monoid m => UFloat m -> m #

foldMap :: Monoid m => (a -> m) -> UFloat a -> m #

foldMap' :: Monoid m => (a -> m) -> UFloat a -> m #

foldr :: (a -> b -> b) -> b -> UFloat a -> b #

foldr' :: (a -> b -> b) -> b -> UFloat a -> b #

foldl :: (b -> a -> b) -> b -> UFloat a -> b #

foldl' :: (b -> a -> b) -> b -> UFloat a -> b #

foldr1 :: (a -> a -> a) -> UFloat a -> a #

foldl1 :: (a -> a -> a) -> UFloat a -> a #

toList :: UFloat a -> [a] #

null :: UFloat a -> Bool #

length :: UFloat a -> Int #

elem :: Eq a => a -> UFloat a -> Bool #

maximum :: Ord a => UFloat a -> a #

minimum :: Ord a => UFloat a -> a #

sum :: Num a => UFloat a -> a #

product :: Num a => UFloat a -> a #

Foldable (UInt :: Type -> Type)

Since: base-4.9.0.0

Instance details

Defined in Data.Foldable

Methods

fold :: Monoid m => UInt m -> m #

foldMap :: Monoid m => (a -> m) -> UInt a -> m #

foldMap' :: Monoid m => (a -> m) -> UInt a -> m #

foldr :: (a -> b -> b) -> b -> UInt a -> b #

foldr' :: (a -> b -> b) -> b -> UInt a -> b #

foldl :: (b -> a -> b) -> b -> UInt a -> b #

foldl' :: (b -> a -> b) -> b -> UInt a -> b #

foldr1 :: (a -> a -> a) -> UInt a -> a #

foldl1 :: (a -> a -> a) -> UInt a -> a #

toList :: UInt a -> [a] #

null :: UInt a -> Bool #

length :: UInt a -> Int #

elem :: Eq a => a -> UInt a -> Bool #

maximum :: Ord a => UInt a -> a #

minimum :: Ord a => UInt a -> a #

sum :: Num a => UInt a -> a #

product :: Num a => UInt a -> a #

Foldable (UWord :: Type -> Type)

Since: base-4.9.0.0

Instance details

Defined in Data.Foldable

Methods

fold :: Monoid m => UWord m -> m #

foldMap :: Monoid m => (a -> m) -> UWord a -> m #

foldMap' :: Monoid m => (a -> m) -> UWord a -> m #

foldr :: (a -> b -> b) -> b -> UWord a -> b #

foldr' :: (a -> b -> b) -> b -> UWord a -> b #

foldl :: (b -> a -> b) -> b -> UWord a -> b #

foldl' :: (b -> a -> b) -> b -> UWord a -> b #

foldr1 :: (a -> a -> a) -> UWord a -> a #

foldl1 :: (a -> a -> a) -> UWord a -> a #

toList :: UWord a -> [a] #

null :: UWord a -> Bool #

length :: UWord a -> Int #

elem :: Eq a => a -> UWord a -> Bool #

maximum :: Ord a => UWord a -> a #

minimum :: Ord a => UWord a -> a #

sum :: Num a => UWord a -> a #

product :: Num a => UWord 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 #

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 (HashMap k) 
Instance details

Defined in Data.HashMap.Internal

Methods

fold :: Monoid m => HashMap k m -> m #

foldMap :: Monoid m => (a -> m) -> HashMap k a -> 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 (Map k)

Folds in order of increasing key.

Instance details

Defined in Data.Map.Internal

Methods

fold :: Monoid m => Map k m -> m #

foldMap :: Monoid m => (a -> m) -> Map k a -> 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 (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 #

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 #

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 #

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 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 #

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 f => Foldable (Cofree f) 
Instance details

Defined in Control.Comonad.Cofree

Methods

fold :: Monoid m => Cofree f m -> m #

foldMap :: Monoid m => (a -> m) -> Cofree f a -> m #

foldMap' :: Monoid m => (a -> m) -> Cofree f a -> m #

foldr :: (a -> b -> b) -> b -> Cofree f a -> b #

foldr' :: (a -> b -> b) -> b -> Cofree f a -> b #

foldl :: (b -> a -> b) -> b -> Cofree f a -> b #

foldl' :: (b -> a -> b) -> b -> Cofree f a -> b #

foldr1 :: (a -> a -> a) -> Cofree f a -> a #

foldl1 :: (a -> a -> a) -> Cofree f a -> a #

toList :: Cofree f a -> [a] #

null :: Cofree f a -> Bool #

length :: Cofree f a -> Int #

elem :: Eq a => a -> Cofree f a -> Bool #

maximum :: Ord a => Cofree f a -> a #

minimum :: Ord a => Cofree f a -> a #

sum :: Num a => Cofree f a -> a #

product :: Num a => Cofree f a -> a #

Foldable (Pair e) 
Instance details

Defined in Data.Strict.Tuple

Methods

fold :: Monoid m => Pair e m -> m #

foldMap :: Monoid m => (a -> m) -> Pair e a -> m #

foldMap' :: Monoid m => (a -> m) -> Pair e a -> m #

foldr :: (a -> b -> b) -> b -> Pair e a -> b #

foldr' :: (a -> b -> b) -> b -> Pair e a -> b #

foldl :: (b -> a -> b) -> b -> Pair e a -> b #

foldl' :: (b -> a -> b) -> b -> Pair e a -> b #

foldr1 :: (a -> a -> a) -> Pair e a -> a #

foldl1 :: (a -> a -> a) -> Pair e a -> a #

toList :: Pair e a -> [a] #

null :: Pair e a -> Bool #

length :: Pair e a -> Int #

elem :: Eq a => a -> Pair e a -> Bool #

maximum :: Ord a => Pair e a -> a #

minimum :: Ord a => Pair e a -> a #

sum :: Num a => Pair e a -> a #

product :: Num a => Pair e a -> a #

Foldable (These a) 
Instance details

Defined in Data.Strict.These

Methods

fold :: Monoid m => These a m -> m #

foldMap :: Monoid m => (a0 -> m) -> These a a0 -> m #

foldMap' :: Monoid m => (a0 -> m) -> These a a0 -> m #

foldr :: (a0 -> b -> b) -> b -> These a a0 -> b #

foldr' :: (a0 -> b -> b) -> b -> These a a0 -> b #

foldl :: (b -> a0 -> b) -> b -> These a a0 -> b #

foldl' :: (b -> a0 -> b) -> b -> These a a0 -> b #

foldr1 :: (a0 -> a0 -> a0) -> These a a0 -> a0 #

foldl1 :: (a0 -> a0 -> a0) -> These a a0 -> a0 #

toList :: These a a0 -> [a0] #

null :: These a a0 -> Bool #

length :: These a a0 -> Int #

elem :: Eq a0 => a0 -> These a a0 -> Bool #

maximum :: Ord a0 => These a a0 -> a0 #

minimum :: Ord a0 => These a a0 -> a0 #

sum :: Num a0 => These a a0 -> a0 #

product :: Num a0 => These a a0 -> a0 #

Foldable (Either e) 
Instance details

Defined in Data.Strict.Either

Methods

fold :: Monoid m => Either e m -> m #

foldMap :: Monoid m => (a -> m) -> Either e a -> m #

foldMap' :: Monoid m => (a -> m) -> Either e a -> m #

foldr :: (a -> b -> b) -> b -> Either e a -> b #

foldr' :: (a -> b -> b) -> b -> Either e a -> b #

foldl :: (b -> a -> b) -> b -> Either e a -> b #

foldl' :: (b -> a -> b) -> b -> Either e a -> b #

foldr1 :: (a -> a -> a) -> Either e a -> a #

foldl1 :: (a -> a -> a) -> Either e a -> a #

toList :: Either e a -> [a] #

null :: Either e a -> Bool #

length :: Either e a -> Int #

elem :: Eq a => a -> Either e a -> Bool #

maximum :: Ord a => Either e a -> a #

minimum :: Ord a => Either e a -> a #

sum :: Num a => Either e a -> a #

product :: Num a => Either e a -> a #

Foldable (These a) 
Instance details

Defined in Data.These

Methods

fold :: Monoid m => These a m -> m #

foldMap :: Monoid m => (a0 -> m) -> These a a0 -> m #

foldMap' :: Monoid m => (a0 -> m) -> These a a0 -> m #

foldr :: (a0 -> b -> b) -> b -> These a a0 -> b #

foldr' :: (a0 -> b -> b) -> b -> These a a0 -> b #

foldl :: (b -> a0 -> b) -> b -> These a a0 -> b #

foldl' :: (b -> a0 -> b) -> b -> These a a0 -> b #

foldr1 :: (a0 -> a0 -> a0) -> These a a0 -> a0 #

foldl1 :: (a0 -> a0 -> a0) -> These a a0 -> a0 #

toList :: These a a0 -> [a0] #

null :: These a a0 -> Bool #

length :: These a a0 -> Int #

elem :: Eq a0 => a0 -> These a a0 -> Bool #

maximum :: Ord a0 => These a a0 -> a0 #

minimum :: Ord a0 => These a a0 -> a0 #

sum :: Num a0 => These a a0 -> a0 #

product :: Num a0 => These a a0 -> a0 #

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 #

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 (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 #

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 #

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 #

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 #

Bifoldable p => Foldable (Join p) 
Instance details

Defined in Data.Bifunctor.Join

Methods

fold :: Monoid m => Join p m -> m #

foldMap :: Monoid m => (a -> m) -> Join p a -> m #

foldMap' :: Monoid m => (a -> m) -> Join p a -> m #

foldr :: (a -> b -> b) -> b -> Join p a -> b #

foldr' :: (a -> b -> b) -> b -> Join p a -> b #

foldl :: (b -> a -> b) -> b -> Join p a -> b #

foldl' :: (b -> a -> b) -> b -> Join p a -> b #

foldr1 :: (a -> a -> a) -> Join p a -> a #

foldl1 :: (a -> a -> a) -> Join p a -> a #

toList :: Join p a -> [a] #

null :: Join p a -> Bool #

length :: Join p a -> Int #

elem :: Eq a => a -> Join p a -> Bool #

maximum :: Ord a => Join p a -> a #

minimum :: Ord a => Join p a -> a #

sum :: Num a => Join p a -> a #

product :: Num a => Join p 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 #

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 (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 #

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 (Tagged s) 
Instance details

Defined in Data.Tagged

Methods

fold :: Monoid m => Tagged s m -> m #

foldMap :: Monoid m => (a -> m) -> Tagged s a -> m #

foldMap' :: Monoid m => (a -> m) -> Tagged s a -> m #

foldr :: (a -> b -> b) -> b -> Tagged s a -> b #

foldr' :: (a -> b -> b) -> b -> Tagged s a -> b #

foldl :: (b -> a -> b) -> b -> Tagged s a -> b #

foldl' :: (b -> a -> b) -> b -> Tagged s a -> b #

foldr1 :: (a -> a -> a) -> Tagged s a -> a #

foldl1 :: (a -> a -> a) -> Tagged s a -> a #

toList :: Tagged s a -> [a] #

null :: Tagged s a -> Bool #

length :: Tagged s a -> Int #

elem :: Eq a => a -> Tagged s a -> Bool #

maximum :: Ord a => Tagged s a -> a #

minimum :: Ord a => Tagged s a -> a #

sum :: Num a => Tagged s a -> a #

product :: Num a => Tagged s a -> a #

(Foldable f, Foldable g) => Foldable (These1 f g) 
Instance details

Defined in Data.Functor.These

Methods

fold :: Monoid m => These1 f g m -> m #

foldMap :: Monoid m => (a -> m) -> These1 f g a -> m #

foldMap' :: Monoid m => (a -> m) -> These1 f g a -> m #

foldr :: (a -> b -> b) -> b -> These1 f g a -> b #

foldr' :: (a -> b -> b) -> b -> These1 f g a -> b #

foldl :: (b -> a -> b) -> b -> These1 f g a -> b #

foldl' :: (b -> a -> b) -> b -> These1 f g a -> b #

foldr1 :: (a -> a -> a) -> These1 f g a -> a #

foldl1 :: (a -> a -> a) -> These1 f g a -> a #

toList :: These1 f g a -> [a] #

null :: These1 f g a -> Bool #

length :: These1 f g a -> Int #

elem :: Eq a => a -> These1 f g a -> Bool #

maximum :: Ord a => These1 f g a -> a #

minimum :: Ord a => These1 f g a -> a #

sum :: Num a => These1 f g a -> a #

product :: Num a => These1 f g a -> a #

Foldable v => Foldable (Vector v n) 
Instance details

Defined in Data.Vector.Generic.Sized.Internal

Methods

fold :: Monoid m => Vector v n m -> m #

foldMap :: Monoid m => (a -> m) -> Vector v n a -> m #

foldMap' :: Monoid m => (a -> m) -> Vector v n a -> m #

foldr :: (a -> b -> b) -> b -> Vector v n a -> b #

foldr' :: (a -> b -> b) -> b -> Vector v n a -> b #

foldl :: (b -> a -> b) -> b -> Vector v n a -> b #

foldl' :: (b -> a -> b) -> b -> Vector v n a -> b #

foldr1 :: (a -> a -> a) -> Vector v n a -> a #

foldl1 :: (a -> a -> a) -> Vector v n a -> a #

toList :: Vector v n a -> [a] #

null :: Vector v n a -> Bool #

length :: Vector v n a -> Int #

elem :: Eq a => a -> Vector v n a -> Bool #

maximum :: Ord a => Vector v n a -> a #

minimum :: Ord a => Vector v n a -> a #

sum :: Num a => Vector v n a -> a #

product :: Num a => Vector v n 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 #

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 #

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 #

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 (Product f g)

Since: base-4.9.0.0

Instance details

Defined in Data.Functor.Product

Methods

fold :: Monoid m => Product f g m -> m #

foldMap :: Monoid m => (a -> m) -> Product f g a -> m #

foldMap' :: Monoid m => (a -> m) -> Product f g a -> m #

foldr :: (a -> b -> b) -> b -> Product f g a -> b #

foldr' :: (a -> b -> b) -> b -> Product f g a -> b #

foldl :: (b -> a -> b) -> b -> Product f g a -> b #

foldl' :: (b -> a -> b) -> b -> Product f g a -> b #

foldr1 :: (a -> a -> a) -> Product f g a -> a #

foldl1 :: (a -> a -> a) -> Product f g a -> a #

toList :: Product f g a -> [a] #

null :: Product f g a -> Bool #

length :: Product f g a -> Int #

elem :: Eq a => a -> Product f g a -> Bool #

maximum :: Ord a => Product f g a -> a #

minimum :: Ord a => Product f g a -> a #

sum :: Num a => Product f g a -> a #

product :: Num a => Product f g a -> a #

(Foldable f, Foldable g) => Foldable (Sum f g)

Since: base-4.9.0.0

Instance details

Defined in Data.Functor.Sum

Methods

fold :: Monoid m => Sum f g m -> m #

foldMap :: Monoid m => (a -> m) -> Sum f g a -> m #

foldMap' :: Monoid m => (a -> m) -> Sum f g a -> m #

foldr :: (a -> b -> b) -> b -> Sum f g a -> b #

foldr' :: (a -> b -> b) -> b -> Sum f g a -> b #

foldl :: (b -> a -> b) -> b -> Sum f g a -> b #

foldl' :: (b -> a -> b) -> b -> Sum f g a -> b #

foldr1 :: (a -> a -> a) -> Sum f g a -> a #

foldl1 :: (a -> a -> a) -> Sum f g a -> a #

toList :: Sum f g a -> [a] #

null :: Sum f g a -> Bool #

length :: Sum f g a -> Int #

elem :: Eq a => a -> Sum f g a -> Bool #

maximum :: Ord a => Sum f g a -> a #

minimum :: Ord a => Sum f g a -> a #

sum :: Num a => Sum f g a -> a #

product :: Num a => Sum 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 #

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 #

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 #

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 #

Bifoldable p => Foldable (WrappedBifunctor p a) 
Instance details

Defined in Data.Bifunctor.Wrapped

Methods

fold :: Monoid m => WrappedBifunctor p a m -> m #

foldMap :: Monoid m => (a0 -> m) -> WrappedBifunctor p a a0 -> m #

foldMap' :: Monoid m => (a0 -> m) -> WrappedBifunctor p a a0 -> m #

foldr :: (a0 -> b -> b) -> b -> WrappedBifunctor p a a0 -> b #

foldr' :: (a0 -> b -> b) -> b -> WrappedBifunctor p a a0 -> b #

foldl :: (b -> a0 -> b) -> b -> WrappedBifunctor p a a0 -> b #

foldl' :: (b -> a0 -> b) -> b -> WrappedBifunctor p a a0 -> b #

foldr1 :: (a0 -> a0 -> a0) -> WrappedBifunctor p a a0 -> a0 #

foldl1 :: (a0 -> a0 -> a0) -> WrappedBifunctor p a a0 -> a0 #

toList :: WrappedBifunctor p a a0 -> [a0] #

null :: WrappedBifunctor p a a0 -> Bool #

length :: WrappedBifunctor p a a0 -> Int #

elem :: Eq a0 => a0 -> WrappedBifunctor p a a0 -> Bool #

maximum :: Ord a0 => WrappedBifunctor p a a0 -> a0 #

minimum :: Ord a0 => WrappedBifunctor p a a0 -> a0 #

sum :: Num a0 => WrappedBifunctor p a a0 -> a0 #

product :: Num a0 => WrappedBifunctor p a a0 -> a0 #

Foldable g => Foldable (Joker g a) 
Instance details

Defined in Data.Bifunctor.Joker

Methods

fold :: Monoid m => Joker g a m -> m #

foldMap :: Monoid m => (a0 -> m) -> Joker g a a0 -> m #

foldMap' :: Monoid m => (a0 -> m) -> Joker g a a0 -> m #

foldr :: (a0 -> b -> b) -> b -> Joker g a a0 -> b #

foldr' :: (a0 -> b -> b) -> b -> Joker g a a0 -> b #

foldl :: (b -> a0 -> b) -> b -> Joker g a a0 -> b #

foldl' :: (b -> a0 -> b) -> b -> Joker g a a0 -> b #

foldr1 :: (a0 -> a0 -> a0) -> Joker g a a0 -> a0 #

foldl1 :: (a0 -> a0 -> a0) -> Joker g a a0 -> a0 #

toList :: Joker g a a0 -> [a0] #

null :: Joker g a a0 -> Bool #

length :: Joker g a a0 -> Int #

elem :: Eq a0 => a0 -> Joker g a a0 -> Bool #

maximum :: Ord a0 => Joker g a a0 -> a0 #

minimum :: Ord a0 => Joker g a a0 -> a0 #

sum :: Num a0 => Joker g a a0 -> a0 #

product :: Num a0 => Joker g a a0 -> a0 #

Bifoldable p => Foldable (Flip p a) 
Instance details

Defined in Data.Bifunctor.Flip

Methods

fold :: Monoid m => Flip p a m -> m #

foldMap :: Monoid m => (a0 -> m) -> Flip p a a0 -> m #

foldMap' :: Monoid m => (a0 -> m) -> Flip p a a0 -> m #

foldr :: (a0 -> b -> b) -> b -> Flip p a a0 -> b #

foldr' :: (a0 -> b -> b) -> b -> Flip p a a0 -> b #

foldl :: (b -> a0 -> b) -> b -> Flip p a a0 -> b #

foldl' :: (b -> a0 -> b) -> b -> Flip p a a0 -> b #

foldr1 :: (a0 -> a0 -> a0) -> Flip p a a0 -> a0 #

foldl1 :: (a0 -> a0 -> a0) -> Flip p a a0 -> a0 #

toList :: Flip p a a0 -> [a0] #

null :: Flip p a a0 -> Bool #

length :: Flip p a a0 -> Int #

elem :: Eq a0 => a0 -> Flip p a a0 -> Bool #

maximum :: Ord a0 => Flip p a a0 -> a0 #

minimum :: Ord a0 => Flip p a a0 -> a0 #

sum :: Num a0 => Flip p a a0 -> a0 #

product :: Num a0 => Flip p a a0 -> a0 #

Foldable (Clown f a :: Type -> Type) 
Instance details

Defined in Data.Bifunctor.Clown

Methods

fold :: Monoid m => Clown f a m -> m #

foldMap :: Monoid m => (a0 -> m) -> Clown f a a0 -> m #

foldMap' :: Monoid m => (a0 -> m) -> Clown f a a0 -> m #

foldr :: (a0 -> b -> b) -> b -> Clown f a a0 -> b #

foldr' :: (a0 -> b -> b) -> b -> Clown f a a0 -> b #

foldl :: (b -> a0 -> b) -> b -> Clown f a a0 -> b #

foldl' :: (b -> a0 -> b) -> b -> Clown f a a0 -> b #

foldr1 :: (a0 -> a0 -> a0) -> Clown f a a0 -> a0 #

foldl1 :: (a0 -> a0 -> a0) -> Clown f a a0 -> a0 #

toList :: Clown f a a0 -> [a0] #

null :: Clown f a a0 -> Bool #

length :: Clown f a a0 -> Int #

elem :: Eq a0 => a0 -> Clown f a a0 -> Bool #

maximum :: Ord a0 => Clown f a a0 -> a0 #

minimum :: Ord a0 => Clown f a a0 -> a0 #

sum :: Num a0 => Clown f a a0 -> a0 #

product :: Num a0 => Clown f a a0 -> a0 #

(Foldable f, Bifoldable p) => Foldable (Tannen f p a) 
Instance details

Defined in Data.Bifunctor.Tannen

Methods

fold :: Monoid m => Tannen f p a m -> m #

foldMap :: Monoid m => (a0 -> m) -> Tannen f p a a0 -> m #

foldMap' :: Monoid m => (a0 -> m) -> Tannen f p a a0 -> m #

foldr :: (a0 -> b -> b) -> b -> Tannen f p a a0 -> b #

foldr' :: (a0 -> b -> b) -> b -> Tannen f p a a0 -> b #

foldl :: (b -> a0 -> b) -> b -> Tannen f p a a0 -> b #

foldl' :: (b -> a0 -> b) -> b -> Tannen f p a a0 -> b #

foldr1 :: (a0 -> a0 -> a0) -> Tannen f p a a0 -> a0 #

foldl1 :: (a0 -> a0 -> a0) -> Tannen f p a a0 -> a0 #

toList :: Tannen f p a a0 -> [a0] #

null :: Tannen f p a a0 -> Bool #

length :: Tannen f p a a0 -> Int #

elem :: Eq a0 => a0 -> Tannen f p a a0 -> Bool #

maximum :: Ord a0 => Tannen f p a a0 -> a0 #

minimum :: Ord a0 => Tannen f p a a0 -> a0 #

sum :: Num a0 => Tannen f p a a0 -> a0 #

product :: Num a0 => Tannen f p a a0 -> a0 #

(Bifoldable p, Foldable g) => Foldable (Biff p f g a) 
Instance details

Defined in Data.Bifunctor.Biff

Methods

fold :: Monoid m => Biff p f g a m -> m #

foldMap :: Monoid m => (a0 -> m) -> Biff p f g a a0 -> m #

foldMap' :: Monoid m => (a0 -> m) -> Biff p f g a a0 -> m #

foldr :: (a0 -> b -> b) -> b -> Biff p f g a a0 -> b #

foldr' :: (a0 -> b -> b) -> b -> Biff p f g a a0 -> b #

foldl :: (b -> a0 -> b) -> b -> Biff p f g a a0 -> b #

foldl' :: (b -> a0 -> b) -> b -> Biff p f g a a0 -> b #

foldr1 :: (a0 -> a0 -> a0) -> Biff p f g a a0 -> a0 #

foldl1 :: (a0 -> a0 -> a0) -> Biff p f g a a0 -> a0 #

toList :: Biff p f g a a0 -> [a0] #

null :: Biff p f g a a0 -> Bool #

length :: Biff p f g a a0 -> Int #

elem :: Eq a0 => a0 -> Biff p f g a a0 -> Bool #

maximum :: Ord a0 => Biff p f g a a0 -> a0 #

minimum :: Ord a0 => Biff p f g a a0 -> a0 #

sum :: Num a0 => Biff p f g a a0 -> a0 #

product :: Num a0 => Biff p f g a a0 -> a0 #

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

and the identity functor Identity and composition functors Compose are from Data.Functor.Identity and Data.Functor.Compose.

A result of the naturality law is a purity law for traverse

traverse pure = pure

(The naturality law is implied by parametricity and thus so is the purity law [1, p15].)

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:

References: [1] The Essence of the Iterator Pattern, Jeremy Gibbons and Bruno C. d. S. Oliveira

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

Instances details
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 IResult 
Instance details

Defined in Data.Aeson.Types.Internal

Methods

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

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

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

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

Traversable Result 
Instance details

Defined in Data.Aeson.Types.Internal

Methods

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

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

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

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

Traversable Complex

Since: base-4.9.0.0

Instance details

Defined in Data.Complex

Methods

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

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

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

sequence :: Monad m => Complex (m a) -> m (Complex 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

Traverses in order of increasing key.

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 Tree 
Instance details

Defined in Data.Tree

Methods

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

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

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

sequence :: Monad m => Tree (m a) -> m (Tree 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 DList 
Instance details

Defined in Data.DList.Internal

Methods

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

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

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

sequence :: Monad m => DList (m a) -> m (DList 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 SmallArray 
Instance details

Defined in Data.Primitive.SmallArray

Methods

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

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

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

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

Traversable Array 
Instance details

Defined in Data.Primitive.Array

Methods

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

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

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

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

Traversable Maybe 
Instance details

Defined in Data.Strict.Maybe

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 (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 (UAddr :: Type -> Type)

Since: base-4.9.0.0

Instance details

Defined in Data.Traversable

Methods

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

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

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

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

Traversable (UChar :: Type -> Type)

Since: base-4.9.0.0

Instance details

Defined in Data.Traversable

Methods

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

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

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

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

Traversable (UDouble :: Type -> Type)

Since: base-4.9.0.0

Instance details

Defined in Data.Traversable

Methods

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

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

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

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

Traversable (UFloat :: Type -> Type)

Since: base-4.9.0.0

Instance details

Defined in Data.Traversable

Methods

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

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

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

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

Traversable (UInt :: Type -> Type)

Since: base-4.9.0.0

Instance details

Defined in Data.Traversable

Methods

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

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

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

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

Traversable (UWord :: Type -> Type)

Since: base-4.9.0.0

Instance details

Defined in Data.Traversable

Methods

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

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

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

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

Traversable (HashMap k) 
Instance details

Defined in Data.HashMap.Internal

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 (Map k)

Traverses in order of increasing key.

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) #

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 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 f => Traversable (Cofree f) 
Instance details

Defined in Control.Comonad.Cofree

Methods

traverse :: Applicative f0 => (a -> f0 b) -> Cofree f a -> f0 (Cofree f b) #

sequenceA :: Applicative f0 => Cofree f (f0 a) -> f0 (Cofree f a) #

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

sequence :: Monad m => Cofree f (m a) -> m (Cofree f a) #

Traversable (Pair e) 
Instance details

Defined in Data.Strict.Tuple

Methods

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

sequenceA :: Applicative f => Pair e (f a) -> f (Pair e a) #

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

sequence :: Monad m => Pair e (m a) -> m (Pair e a) #

Traversable (These a) 
Instance details

Defined in Data.Strict.These

Methods

traverse :: Applicative f => (a0 -> f b) -> These a a0 -> f (These a b) #

sequenceA :: Applicative f => These a (f a0) -> f (These a a0) #

mapM :: Monad m => (a0 -> m b) -> These a a0 -> m (These a b) #

sequence :: Monad m => These a (m a0) -> m (These a a0) #

Traversable (Either e) 
Instance details

Defined in Data.Strict.Either

Methods

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

sequenceA :: Applicative f => Either e (f a) -> f (Either e a) #

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

sequence :: Monad m => Either e (m a) -> m (Either e a) #

Traversable (These a) 
Instance details

Defined in Data.These

Methods

traverse :: Applicative f => (a0 -> f b) -> These a a0 -> f (These a b) #

sequenceA :: Applicative f => These a (f a0) -> f (These a a0) #

mapM :: Monad m => (a0 -> m b) -> These a a0 -> m (These a b) #

sequence :: Monad m => These a (m a0) -> m (These a a0) #

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 (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) #

Bitraversable p => Traversable (Join p) 
Instance details

Defined in Data.Bifunctor.Join

Methods

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

sequenceA :: Applicative f => Join p (f a) -> f (Join p a) #

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

sequence :: Monad m => Join p (m a) -> m (Join p 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 (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 (Tagged s) 
Instance details

Defined in Data.Tagged

Methods

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

sequenceA :: Applicative f => Tagged s (f a) -> f (Tagged s a) #

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

sequence :: Monad m => Tagged s (m a) -> m (Tagged s a) #

(Traversable f, Traversable g) => Traversable (These1 f g) 
Instance details

Defined in Data.Functor.These

Methods

traverse :: Applicative f0 => (a -> f0 b) -> These1 f g a -> f0 (These1 f g b) #

sequenceA :: Applicative f0 => These1 f g (f0 a) -> f0 (These1 f g a) #

mapM :: Monad m => (a -> m b) -> These1 f g a -> m (These1 f g b) #

sequence :: Monad m => These1 f g (m a) -> m (These1 f g a) #

Traversable v => Traversable (Vector v n) 
Instance details

Defined in Data.Vector.Generic.Sized.Internal

Methods

traverse :: Applicative f => (a -> f b) -> Vector v n a -> f (Vector v n b) #

sequenceA :: Applicative f => Vector v n (f a) -> f (Vector v n a) #

mapM :: Monad m => (a -> m b) -> Vector v n a -> m (Vector v n b) #

sequence :: Monad m => Vector v n (m a) -> m (Vector v n 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 g) => Traversable (Product f g)

Since: base-4.9.0.0

Instance details

Defined in Data.Functor.Product

Methods

traverse :: Applicative f0 => (a -> f0 b) -> Product f g a -> f0 (Product f g b) #

sequenceA :: Applicative f0 => Product f g (f0 a) -> f0 (Product f g a) #

mapM :: Monad m => (a -> m b) -> Product f g a -> m (Product f g b) #

sequence :: Monad m => Product f g (m a) -> m (Product f g a) #

(Traversable f, Traversable g) => Traversable (Sum f g)

Since: base-4.9.0.0

Instance details

Defined in Data.Functor.Sum

Methods

traverse :: Applicative f0 => (a -> f0 b) -> Sum f g a -> f0 (Sum f g b) #

sequenceA :: Applicative f0 => Sum f g (f0 a) -> f0 (Sum f g a) #

mapM :: Monad m => (a -> m b) -> Sum f g a -> m (Sum f g b) #

sequence :: Monad m => Sum f g (m a) -> m (Sum 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) #

Bitraversable p => Traversable (WrappedBifunctor p a) 
Instance details

Defined in Data.Bifunctor.Wrapped

Methods

traverse :: Applicative f => (a0 -> f b) -> WrappedBifunctor p a a0 -> f (WrappedBifunctor p a b) #

sequenceA :: Applicative f => WrappedBifunctor p a (f a0) -> f (WrappedBifunctor p a a0) #

mapM :: Monad m => (a0 -> m b) -> WrappedBifunctor p a a0 -> m (WrappedBifunctor p a b) #

sequence :: Monad m => WrappedBifunctor p a (m a0) -> m (WrappedBifunctor p a a0) #

Traversable g => Traversable (Joker g a) 
Instance details

Defined in Data.Bifunctor.Joker

Methods

traverse :: Applicative f => (a0 -> f b) -> Joker g a a0 -> f (Joker g a b) #

sequenceA :: Applicative f => Joker g a (f a0) -> f (Joker g a a0) #

mapM :: Monad m => (a0 -> m b) -> Joker g a a0 -> m (Joker g a b) #

sequence :: Monad m => Joker g a (m a0) -> m (Joker g a a0) #

Bitraversable p => Traversable (Flip p a) 
Instance details

Defined in Data.Bifunctor.Flip

Methods

traverse :: Applicative f => (a0 -> f b) -> Flip p a a0 -> f (Flip p a b) #

sequenceA :: Applicative f => Flip p a (f a0) -> f (Flip p a a0) #

mapM :: Monad m => (a0 -> m b) -> Flip p a a0 -> m (Flip p a b) #

sequence :: Monad m => Flip p a (m a0) -> m (Flip p a a0) #

Traversable (Clown f a :: Type -> Type) 
Instance details

Defined in Data.Bifunctor.Clown

Methods

traverse :: Applicative f0 => (a0 -> f0 b) -> Clown f a a0 -> f0 (Clown f a b) #

sequenceA :: Applicative f0 => Clown f a (f0 a0) -> f0 (Clown f a a0) #

mapM :: Monad m => (a0 -> m b) -> Clown f a a0 -> m (Clown f a b) #

sequence :: Monad m => Clown f a (m a0) -> m (Clown f a a0) #

(Traversable f, Bitraversable p) => Traversable (Tannen f p a) 
Instance details

Defined in Data.Bifunctor.Tannen

Methods

traverse :: Applicative f0 => (a0 -> f0 b) -> Tannen f p a a0 -> f0 (Tannen f p a b) #

sequenceA :: Applicative f0 => Tannen f p a (f0 a0) -> f0 (Tannen f p a a0) #

mapM :: Monad m => (a0 -> m b) -> Tannen f p a a0 -> m (Tannen f p a b) #

sequence :: Monad m => Tannen f p a (m a0) -> m (Tannen f p a a0) #

(Bitraversable p, Traversable g) => Traversable (Biff p f g a) 
Instance details

Defined in Data.Bifunctor.Biff

Methods

traverse :: Applicative f0 => (a0 -> f0 b) -> Biff p f g a a0 -> f0 (Biff p f g a b) #

sequenceA :: Applicative f0 => Biff p f g a (f0 a0) -> f0 (Biff p f g a a0) #

mapM :: Monad m => (a0 -> m b) -> Biff p f g a a0 -> m (Biff p f g a b) #

sequence :: Monad m => Biff p f g a (m a0) -> m (Biff p f g a a0) #

data TyCon #

Instances

Instances details
Eq TyCon 
Instance details

Defined in GHC.Classes

Methods

(==) :: TyCon -> TyCon -> Bool #

(/=) :: TyCon -> TyCon -> Bool #

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 #

Show TyCon

Since: base-2.1

Instance details

Defined in GHC.Show

Methods

showsPrec :: Int -> TyCon -> ShowS #

show :: TyCon -> String #

showList :: [TyCon] -> ShowS #

liftM :: Monad m => (a1 -> r) -> m a1 -> m r #

Promote a function to a monad.

(<$>) :: 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)

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 idid

If you supply first and second, ensure:

first idid
second idid

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.

secondbimap id

Examples

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

Instances

Instances details
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 Pair 
Instance details

Defined in Data.Strict.Tuple

Methods

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

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

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

Bifunctor These 
Instance details

Defined in Data.Strict.These

Methods

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

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

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

Bifunctor Either 
Instance details

Defined in Data.Strict.Either

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 These 
Instance details

Defined in Data.These

Methods

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

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

second :: (b -> c) -> These a b -> These 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 (Tagged :: Type -> Type -> Type) 
Instance details

Defined in Data.Tagged

Methods

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

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

second :: (b -> c) -> Tagged a b -> Tagged 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 p => Bifunctor (WrappedBifunctor p) 
Instance details

Defined in Data.Bifunctor.Wrapped

Methods

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

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

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

Functor g => Bifunctor (Joker g :: Type -> Type -> Type) 
Instance details

Defined in Data.Bifunctor.Joker

Methods

bimap :: (a -> b) -> (c -> d) -> Joker g a c -> Joker g b d #

first :: (a -> b) -> Joker g a c -> Joker g b c #

second :: (b -> c) -> Joker g a b -> Joker g a c #

Bifunctor p => Bifunctor (Flip p) 
Instance details

Defined in Data.Bifunctor.Flip

Methods

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

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

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

Functor f => Bifunctor (Clown f :: Type -> Type -> Type) 
Instance details

Defined in Data.Bifunctor.Clown

Methods

bimap :: (a -> b) -> (c -> d) -> Clown f a c -> Clown f b d #

first :: (a -> b) -> Clown f a c -> Clown f b c #

second :: (b -> c) -> Clown f a b -> Clown f 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 p, Bifunctor q) => Bifunctor (Sum p q) 
Instance details

Defined in Data.Bifunctor.Sum

Methods

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

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

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

(Bifunctor f, Bifunctor g) => Bifunctor (Product f g) 
Instance details

Defined in Data.Bifunctor.Product

Methods

bimap :: (a -> b) -> (c -> d) -> Product f g a c -> Product f g b d #

first :: (a -> b) -> Product f g a c -> Product f g b c #

second :: (b -> c) -> Product f g a b -> Product f g 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) #

(Functor f, Bifunctor p) => Bifunctor (Tannen f p) 
Instance details

Defined in Data.Bifunctor.Tannen

Methods

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

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

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

(Bifunctor p, Functor f, Functor g) => Bifunctor (Biff p f g) 
Instance details

Defined in Data.Bifunctor.Biff

Methods

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

first :: (a -> b) -> Biff p f g a c -> Biff p f g b c #

second :: (b -> c) -> Biff p f g a b -> Biff p f g a c #

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:

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

Instances details
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 IResult 
Instance details

Defined in Data.Aeson.Types.Internal

Methods

empty :: IResult a #

(<|>) :: IResult a -> IResult a -> IResult a #

some :: IResult a -> IResult [a] #

many :: IResult a -> IResult [a] #

Alternative Result 
Instance details

Defined in Data.Aeson.Types.Internal

Methods

empty :: Result a #

(<|>) :: Result a -> Result a -> Result a #

some :: Result a -> Result [a] #

many :: Result a -> Result [a] #

Alternative Parser 
Instance details

Defined in Data.Aeson.Types.Internal

Methods

empty :: Parser a #

(<|>) :: Parser a -> Parser a -> Parser a #

some :: Parser a -> Parser [a] #

many :: Parser a -> Parser [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 ReadPrec

Since: base-4.6.0.0

Instance details

Defined in Text.ParserCombinators.ReadPrec

Methods

empty :: ReadPrec a #

(<|>) :: ReadPrec a -> ReadPrec a -> ReadPrec a #

some :: ReadPrec a -> ReadPrec [a] #

many :: ReadPrec a -> ReadPrec [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 Get

Since: binary-0.7.0.0

Instance details

Defined in Data.Binary.Get.Internal

Methods

empty :: Get a #

(<|>) :: Get a -> Get a -> Get a #

some :: Get a -> Get [a] #

many :: Get a -> Get [a] #

Alternative BinaryParser 
Instance details

Defined in BinaryParser

Alternative Get 
Instance details

Defined in Data.Serialize.Get

Methods

empty :: Get a #

(<|>) :: Get a -> Get a -> Get a #

some :: Get a -> Get [a] #

many :: Get a -> Get [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 BinaryDeserializer 
Instance details

Defined in Data.Deserializer

Alternative CerealDeserializer 
Instance details

Defined in Data.Deserializer

Alternative DList 
Instance details

Defined in Data.DList.Internal

Methods

empty :: DList a #

(<|>) :: DList a -> DList a -> DList a #

some :: DList a -> DList [a] #

many :: DList a -> DList [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 SmallArray 
Instance details

Defined in Data.Primitive.SmallArray

Alternative Array 
Instance details

Defined in Data.Primitive.Array

Methods

empty :: Array a #

(<|>) :: Array a -> Array a -> Array a #

some :: Array a -> Array [a] #

many :: Array a -> Array [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] #

Alternative (Parser i) 
Instance details

Defined in Data.Attoparsec.Internal.Types

Methods

empty :: Parser i a #

(<|>) :: Parser i a -> Parser i a -> Parser i a #

some :: Parser i a -> Parser i [a] #

many :: Parser i a -> Parser i [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 μ => Alternative (LittleEndianDeserializer μ) 
Instance details

Defined in Data.Deserializer

Alternative μ => Alternative (BigEndianDeserializer μ) 
Instance details

Defined in Data.Deserializer

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 m => Alternative (Kleisli m a)

Since: base-4.14.0.0

Instance details

Defined in Control.Arrow

Methods

empty :: Kleisli m a a0 #

(<|>) :: Kleisli m a a0 -> Kleisli m a a0 -> Kleisli m a a0 #

some :: Kleisli m a a0 -> Kleisli m a [a0] #

many :: Kleisli m a a0 -> Kleisli m a [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, 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 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] #

(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] #

(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.Lazy

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 f, Alternative g) => Alternative (Product f g)

Since: base-4.9.0.0

Instance details

Defined in Data.Functor.Product

Methods

empty :: Product f g a #

(<|>) :: Product f g a -> Product f g a -> Product f g a #

some :: Product f g a -> Product f g [a] #

many :: Product f g a -> Product f g [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] #

(Monoid w, Functor m, MonadPlus m) => Alternative (RWST r w s m) 
Instance details

Defined in Control.Monad.Trans.RWS.Lazy

Methods

empty :: RWST r w s m a #

(<|>) :: RWST r w s m a -> RWST r w s m a -> RWST r w s m a #

some :: RWST r w s m a -> RWST r w s m [a] #

many :: RWST r w s m a -> RWST r w s m [a] #

(Monoid w, Functor m, MonadPlus m) => Alternative (RWST r w s m) 
Instance details

Defined in Control.Monad.Trans.RWS.Strict

Methods

empty :: RWST r w s m a #

(<|>) :: RWST r w s m a -> RWST r w s m a -> RWST r w s m a #

some :: RWST r w s m a -> RWST r w s m [a] #

many :: RWST r w s m a -> RWST r w s m [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

Instances details
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 IResult 
Instance details

Defined in Data.Aeson.Types.Internal

Methods

mzero :: IResult a #

mplus :: IResult a -> IResult a -> IResult a #

MonadPlus Result 
Instance details

Defined in Data.Aeson.Types.Internal

Methods

mzero :: Result a #

mplus :: Result a -> Result a -> Result a #

MonadPlus Parser 
Instance details

Defined in Data.Aeson.Types.Internal

Methods

mzero :: Parser a #

mplus :: Parser a -> Parser a -> Parser 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 ReadPrec

Since: base-2.1

Instance details

Defined in Text.ParserCombinators.ReadPrec

Methods

mzero :: ReadPrec a #

mplus :: ReadPrec a -> ReadPrec a -> ReadPrec 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 Get

Since: binary-0.7.1.0

Instance details

Defined in Data.Binary.Get.Internal

Methods

mzero :: Get a #

mplus :: Get a -> Get a -> Get a #

MonadPlus BinaryParser 
Instance details

Defined in BinaryParser

MonadPlus Get 
Instance details

Defined in Data.Serialize.Get

Methods

mzero :: Get a #

mplus :: Get a -> Get a -> Get a #

MonadPlus Seq 
Instance details

Defined in Data.Sequence.Internal

Methods

mzero :: Seq a #

mplus :: Seq a -> Seq a -> Seq a #

MonadPlus DList 
Instance details

Defined in Data.DList.Internal

Methods

mzero :: DList a #

mplus :: DList a -> DList a -> DList a #

MonadPlus Vector 
Instance details

Defined in Data.Vector

Methods

mzero :: Vector a #

mplus :: Vector a -> Vector a -> Vector a #

MonadPlus SmallArray 
Instance details

Defined in Data.Primitive.SmallArray

MonadPlus Array 
Instance details

Defined in Data.Primitive.Array

Methods

mzero :: Array a #

mplus :: Array a -> Array a -> Array 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 #

MonadPlus (Parser i) 
Instance details

Defined in Data.Attoparsec.Internal.Types

Methods

mzero :: Parser i a #

mplus :: Parser i a -> Parser i a -> Parser i 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 m => MonadPlus (Kleisli m a)

Since: base-4.14.0.0

Instance details

Defined in Control.Arrow

Methods

mzero :: Kleisli m a a0 #

mplus :: Kleisli m a a0 -> Kleisli m a a0 -> Kleisli m a a0 #

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 #

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 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 #

(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 #

(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.Lazy

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 f, MonadPlus g) => MonadPlus (Product f g)

Since: base-4.9.0.0

Instance details

Defined in Data.Functor.Product

Methods

mzero :: Product f g a #

mplus :: Product f g a -> Product f g a -> Product f g 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 #

(Monoid w, MonadPlus m) => MonadPlus (RWST r w s m) 
Instance details

Defined in Control.Monad.Trans.RWS.Lazy

Methods

mzero :: RWST r w s m a #

mplus :: RWST r w s m a -> RWST r w s m a -> RWST r w s m a #

(Monoid w, MonadPlus m) => MonadPlus (RWST r w s m) 
Instance details

Defined in Control.Monad.Trans.RWS.Strict

Methods

mzero :: RWST r w s m a #

mplus :: RWST r w s m a -> RWST r w s m a -> RWST r w s m a #

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:

Methods

liftIO :: IO a -> m a #

Lift a computation from the IO monad.

Instances

Instances details
MonadIO IO

Since: base-4.9.0.0

Instance details

Defined in Control.Monad.IO.Class

Methods

liftIO :: IO a -> IO a #

MonadIO Q 
Instance details

Defined in Language.Haskell.TH.Syntax

Methods

liftIO :: IO a -> Q a #

MonadIO m => MonadIO (MaybeT m) 
Instance details

Defined in Control.Monad.Trans.Maybe

Methods

liftIO :: IO a -> MaybeT 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 #

MonadIO m => MonadIO (ExceptT e m) 
Instance details

Defined in Control.Monad.Trans.Except

Methods

liftIO :: IO a -> ExceptT e 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.Lazy

Methods

liftIO :: IO a -> StateT s m a #

(Monoid w, MonadIO m) => MonadIO (RWST r w s m) 
Instance details

Defined in Control.Monad.Trans.RWS.Lazy

Methods

liftIO :: IO a -> RWST r w s m a #

(Monoid w, MonadIO m) => MonadIO (RWST r w s m) 
Instance details

Defined in Control.Monad.Trans.RWS.Strict

Methods

liftIO :: IO a -> RWST r w s 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.

Using ApplicativeDo: 'replicateM 5 as' can be understood as the do expression

do a1 <- as
   a2 <- as
   a3 <- as
   a4 <- as
   a5 <- as
   pure [a1,a2,a3,a4,a5]

Note the Applicative constraint.

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 monad.

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

Repeat an action indefinitely.

Using ApplicativeDo: 'forever as' can be understood as the pseudo-do expression

do as
   as
   ..

with as repeating.

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.

'(bs >=> cs) a' can be understood as the do expression

do b <- bs a
   cs b

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_.

for :: (Traversable t, Applicative f) => t a -> (a -> f b) -> f (t b) #

for is traverse with its arguments flipped. For a version that ignores the results see for_.

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

One or none.

newtype WrappedMonad (m :: Type -> Type) a #

Constructors

WrapMonad 

Fields

Instances

Instances details
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 #

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 #

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 #

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] #

Generic1 (WrappedMonad m :: Type -> Type)

Since: base-4.7.0.0

Instance details

Defined in Control.Applicative

Associated Types

type Rep1 (WrappedMonad m) :: k -> Type #

Methods

from1 :: forall (a :: k). WrappedMonad m a -> Rep1 (WrappedMonad m) a #

to1 :: forall (a :: k). Rep1 (WrappedMonad m) a -> WrappedMonad m a #

(Typeable m, Typeable a, Data (m a)) => Data (WrappedMonad m a)

Since: base-4.14.0.0

Instance details

Defined in Data.Data

Methods

gfoldl :: (forall d b. Data d => c (d -> b) -> d -> c b) -> (forall g. g -> c g) -> WrappedMonad m a -> c (WrappedMonad m a) #

gunfold :: (forall b r. Data b => c (b -> r) -> c r) -> (forall r. r -> c r) -> Constr -> c (WrappedMonad m a) #

toConstr :: WrappedMonad m a -> Constr #

dataTypeOf :: WrappedMonad m a -> DataType #

dataCast1 :: Typeable t => (forall d. Data d => c (t d)) -> Maybe (c (WrappedMonad m a)) #

dataCast2 :: Typeable t => (forall d e. (Data d, Data e) => c (t d e)) -> Maybe (c (WrappedMonad m a)) #

gmapT :: (forall b. Data b => b -> b) -> WrappedMonad m a -> WrappedMonad m a #

gmapQl :: (r -> r' -> r) -> r -> (forall d. Data d => d -> r') -> WrappedMonad m a -> r #

gmapQr :: forall r r'. (r' -> r -> r) -> r -> (forall d. Data d => d -> r') -> WrappedMonad m a -> r #

gmapQ :: (forall d. Data d => d -> u) -> WrappedMonad m a -> [u] #

gmapQi :: Int -> (forall d. Data d => d -> u) -> WrappedMonad m a -> u #

gmapM :: Monad m0 => (forall d. Data d => d -> m0 d) -> WrappedMonad m a -> m0 (WrappedMonad m a) #

gmapMp :: MonadPlus m0 => (forall d. Data d => d -> m0 d) -> WrappedMonad m a -> m0 (WrappedMonad m a) #

gmapMo :: MonadPlus m0 => (forall d. Data d => d -> m0 d) -> WrappedMonad m a -> m0 (WrappedMonad m a) #

Generic (WrappedMonad m a)

Since: base-4.7.0.0

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 #

type Rep1 (WrappedMonad m :: Type -> Type) 
Instance details

Defined in Control.Applicative

type Rep1 (WrappedMonad m :: Type -> Type) = D1 ('MetaData "WrappedMonad" "Control.Applicative" "base" 'True) (C1 ('MetaCons "WrapMonad" 'PrefixI 'True) (S1 ('MetaSel ('Just "unwrapMonad") 'NoSourceUnpackedness 'NoSourceStrictness 'DecidedLazy) (Rec1 m)))
type Rep (WrappedMonad m a) 
Instance details

Defined in Control.Applicative

type Rep (WrappedMonad m a) = D1 ('MetaData "WrappedMonad" "Control.Applicative" "base" 'True) (C1 ('MetaCons "WrapMonad" 'PrefixI 'True) (S1 ('MetaSel ('Just "unwrapMonad") 'NoSourceUnpackedness 'NoSourceStrictness 'DecidedLazy) (Rec0 (m a))))

newtype WrappedArrow (a :: Type -> Type -> Type) b c #

Constructors

WrapArrow 

Fields

Instances

Instances details
Generic1 (WrappedArrow a b :: Type -> Type)

Since: base-4.7.0.0

Instance details

Defined in Control.Applicative

Associated Types

type Rep1 (WrappedArrow a b) :: k -> Type #

Methods

from1 :: forall (a0 :: k). WrappedArrow a b a0 -> Rep1 (WrappedArrow a b) a0 #

to1 :: forall (a0 :: k). Rep1 (WrappedArrow a b) a0 -> WrappedArrow a b a0 #

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 #

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 #

(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] #

(Typeable a, Typeable b, Typeable c, Data (a b c)) => Data (WrappedArrow a b c)

Since: base-4.14.0.0

Instance details

Defined in Data.Data

Methods

gfoldl :: (forall d b0. Data d => c0 (d -> b0) -> d -> c0 b0) -> (forall g. g -> c0 g) -> WrappedArrow a b c -> c0 (WrappedArrow a b c) #

gunfold :: (forall b0 r. Data b0 => c0 (b0 -> r) -> c0 r) -> (forall r. r -> c0 r) -> Constr -> c0 (WrappedArrow a b c) #

toConstr :: WrappedArrow a b c -> Constr #

dataTypeOf :: WrappedArrow a b c -> DataType #

dataCast1 :: Typeable t => (forall d. Data d => c0 (t d)) -> Maybe (c0 (WrappedArrow a b c)) #

dataCast2 :: Typeable t => (forall d e. (Data d, Data e) => c0 (t d e)) -> Maybe (c0 (WrappedArrow a b c)) #

gmapT :: (forall b0. Data b0 => b0 -> b0) -> WrappedArrow a b c -> WrappedArrow a b c #

gmapQl :: (r -> r' -> r) -> r -> (forall d. Data d => d -> r') -> WrappedArrow a b c -> r #

gmapQr :: forall r r'. (r' -> r -> r) -> r -> (forall d. Data d => d -> r') -> WrappedArrow a b c -> r #

gmapQ :: (forall d. Data d => d -> u) -> WrappedArrow a b c -> [u] #

gmapQi :: Int -> (forall d. Data d => d -> u) -> WrappedArrow a b c -> u #

gmapM :: Monad m => (forall d. Data d => d -> m d) -> WrappedArrow a b c -> m (WrappedArrow a b c) #

gmapMp :: MonadPlus m => (forall d. Data d => d -> m d) -> WrappedArrow a b c -> m (WrappedArrow a b c) #

gmapMo :: MonadPlus m => (forall d. Data d => d -> m d) -> WrappedArrow a b c -> m (WrappedArrow a b c) #

Generic (WrappedArrow a b c)

Since: base-4.7.0.0

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 #

type Rep1 (WrappedArrow a b :: Type -> Type) 
Instance details

Defined in Control.Applicative

type Rep1 (WrappedArrow a b :: Type -> Type) = D1 ('MetaData "WrappedArrow" "Control.Applicative" "base" 'True) (C1 ('MetaCons "WrapArrow" 'PrefixI 'True) (S1 ('MetaSel ('Just "unwrapArrow") 'NoSourceUnpackedness 'NoSourceStrictness 'DecidedLazy) (Rec1 (a b))))
type Rep (WrappedArrow a b c) 
Instance details

Defined in Control.Applicative

type Rep (WrappedArrow a b c) = D1 ('MetaData "WrappedArrow" "Control.Applicative" "base" 'True) (C1 ('MetaCons "WrapArrow" 'PrefixI 'True) (S1 ('MetaSel ('Just "unwrapArrow") 'NoSourceUnpackedness 'NoSourceStrictness 'DecidedLazy) (Rec0 (a b c))))

newtype ZipList a #

Lists, but with an Applicative functor based on zipping.

Constructors

ZipList 

Fields

Instances

Instances details
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 #

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] #

IsList (ZipList a)

Since: base-4.15.0.0

Instance details

Defined in GHC.Exts

Associated Types

type Item (ZipList a) #

Methods

fromList :: [Item (ZipList a)] -> ZipList a #

fromListN :: Int -> [Item (ZipList a)] -> ZipList a #

toList :: ZipList a -> [Item (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 #

Data a => Data (ZipList a)

Since: base-4.14.0.0

Instance details

Defined in Data.Data

Methods

gfoldl :: (forall d b. Data d => c (d -> b) -> d -> c b) -> (forall g. g -> c g) -> ZipList a -> c (ZipList a) #

gunfold :: (forall b r. Data b => c (b -> r) -> c r) -> (forall r. r -> c r) -> Constr -> c (ZipList a) #

toConstr :: ZipList a -> Constr #

dataTypeOf :: ZipList a -> DataType #

dataCast1 :: Typeable t => (forall d. Data d => c (t d)) -> Maybe (c (ZipList a)) #

dataCast2 :: Typeable t => (forall d e. (Data d, Data e) => c (t d e)) -> Maybe (c (ZipList a)) #

gmapT :: (forall b. Data b => b -> b) -> ZipList a -> ZipList a #

gmapQl :: (r -> r' -> r) -> r -> (forall d. Data d => d -> r') -> ZipList a -> r #

gmapQr :: forall r r'. (r' -> r -> r) -> r -> (forall d. Data d => d -> r') -> ZipList a -> r #

gmapQ :: (forall d. Data d => d -> u) -> ZipList a -> [u] #

gmapQi :: Int -> (forall d. Data d => d -> u) -> ZipList a -> u #

gmapM :: Monad m => (forall d. Data d => d -> m d) -> ZipList a -> m (ZipList a) #

gmapMp :: MonadPlus m => (forall d. Data d => d -> m d) -> ZipList a -> m (ZipList a) #

gmapMo :: MonadPlus m => (forall d. Data d => d -> m d) -> ZipList a -> m (ZipList 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 #

Read a => Read (ZipList a)

Since: base-4.7.0.0

Instance details

Defined in Control.Applicative

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)

Since: base-4.7.0.0

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 #

Generic1 ZipList

Since: base-4.7.0.0

Instance details

Defined in Control.Applicative

Associated Types

type Rep1 ZipList :: k -> Type #

Methods

from1 :: forall (a :: k). ZipList a -> Rep1 ZipList a #

to1 :: forall (a :: k). Rep1 ZipList a -> ZipList a #

type Rep (ZipList a) 
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 Item (ZipList a) 
Instance details

Defined in GHC.Exts

type Item (ZipList a) = a
type Rep1 ZipList 
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 [])))

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

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

Instances

Instances details
Exception Void

Since: base-4.8.0.0

Instance details

Defined in Data.Void

Exception PatternMatchFail

Since: base-4.0

Instance details

Defined in Control.Exception.Base

Exception RecSelError

Since: base-4.0

Instance details

Defined in Control.Exception.Base

Exception RecConError

Since: base-4.0

Instance details

Defined in Control.Exception.Base

Exception RecUpdError

Since: base-4.0

Instance details

Defined in Control.Exception.Base

Exception NoMethodError

Since: base-4.0

Instance details

Defined in Control.Exception.Base

Exception TypeError

Since: base-4.9.0.0

Instance details

Defined in Control.Exception.Base

Exception NonTermination

Since: base-4.0

Instance details

Defined in Control.Exception.Base

Exception NestedAtomically

Since: base-4.0

Instance details

Defined in Control.Exception.Base

Exception BlockedIndefinitelyOnMVar

Since: base-4.1.0.0

Instance details

Defined in GHC.IO.Exception

Exception BlockedIndefinitelyOnSTM

Since: base-4.1.0.0

Instance details

Defined in GHC.IO.Exception

Exception Deadlock

Since: base-4.1.0.0

Instance details

Defined in GHC.IO.Exception

Exception AllocationLimitExceeded

Since: base-4.8.0.0

Instance details

Defined in GHC.IO.Exception

Exception CompactionFailed

Since: base-4.10.0.0

Instance details

Defined in GHC.IO.Exception

Exception AssertionFailed

Since: base-4.1.0.0

Instance details

Defined in GHC.IO.Exception

Exception SomeAsyncException

Since: base-4.7.0.0

Instance details

Defined in GHC.IO.Exception

Exception AsyncException

Since: base-4.7.0.0

Instance details

Defined in GHC.IO.Exception

Exception ArrayException

Since: base-4.1.0.0

Instance details

Defined in GHC.IO.Exception

Exception FixIOException

Since: base-4.11.0.0

Instance details

Defined in GHC.IO.Exception

Exception ExitCode

Since: base-4.1.0.0

Instance details

Defined in GHC.IO.Exception

Exception IOException

Since: base-4.1.0.0

Instance details

Defined in GHC.IO.Exception

Exception ArithException

Since: base-4.0.0.0

Instance details

Defined in GHC.Exception.Type

Exception SomeException

Since: base-3.0

Instance details

Defined in GHC.Exception.Type

Exception UnicodeException 
Instance details

Defined in Data.Text.Encoding.Error

Exception FieldError Source # 
Instance details

Defined in Preql.Wire.Errors

Exception QueryError Source # 
Instance details

Defined in Preql.Wire.Errors

typeOf7 :: Typeable t => t a b c d e f g -> TypeRep #

typeOf6 :: Typeable t => t a b c d e f -> TypeRep #

typeOf5 :: Typeable t => t a b c d e -> TypeRep #

typeOf4 :: Typeable t => t a b c d -> TypeRep #

typeOf3 :: Typeable t => t a b c -> TypeRep #

typeOf2 :: Typeable t => t a b -> TypeRep #

typeOf1 :: Typeable t => t a -> TypeRep #

rnfTypeRep :: TypeRep -> () #

Force a TypeRep to normal form.

typeRepFingerprint :: TypeRep -> Fingerprint #

Takes a value of type a and returns a concrete representation of that type.

Since: base-4.7.0.0

typeRepTyCon :: TypeRep -> TyCon #

Observe the type constructor of a quantified type representation.

typeRepArgs :: TypeRep -> [TypeRep] #

Observe the argument types of a type representation

splitTyConApp :: TypeRep -> (TyCon, [TypeRep]) #

Splits a type constructor application. Note that if the type constructor is polymorphic, this will not return the kinds that were used.

mkFunTy :: TypeRep -> TypeRep -> TypeRep #

Build a function type.

funResultTy :: TypeRep -> TypeRep -> Maybe TypeRep #

Applies a type to a function type. Returns: Just u if the first argument represents a function of type t -> u and the second argument represents a function of type t. Otherwise, returns Nothing.

gcast2 :: forall k1 k2 k3 c (t :: k2 -> k3 -> k1) (t' :: k2 -> k3 -> k1) (a :: k2) (b :: k3). (Typeable t, Typeable t') => c (t a b) -> Maybe (c (t' a b)) #

Cast over k1 -> k2 -> k3

gcast1 :: forall k1 k2 c (t :: k2 -> k1) (t' :: k2 -> k1) (a :: k2). (Typeable t, Typeable t') => c (t a) -> Maybe (c (t' a)) #

Cast over k1 -> k2

gcast :: forall k (a :: k) (b :: k) c. (Typeable a, Typeable b) => c a -> Maybe (c b) #

A flexible variation parameterised in a type constructor

eqT :: forall k (a :: k) (b :: k). (Typeable a, Typeable b) => Maybe (a :~: b) #

Extract a witness of equality of two types

Since: base-4.7.0.0

cast :: (Typeable a, Typeable b) => a -> Maybe b #

The type-safe cast operation

showsTypeRep :: TypeRep -> ShowS #

Show a type representation

typeRep :: forall k proxy (a :: k). Typeable a => proxy a -> TypeRep #

Takes a value of type a and returns a concrete representation of that type.

Since: base-4.7.0.0

typeOf :: Typeable a => a -> TypeRep #

Observe a type representation for the type of a value.

type TypeRep = SomeTypeRep #

A quantified type representation.

rnfTyCon :: TyCon -> () #

newtype Const a (b :: k) #

The Const functor.

Constructors

Const 

Fields

Instances

Instances details
Generic1 (Const a :: k -> Type)

Since: base-4.9.0.0

Instance details

Defined in Data.Functor.Const

Associated Types

type Rep1 (Const a) :: k -> Type #

Methods

from1 :: forall (a0 :: k0). Const a a0 -> Rep1 (Const a) a0 #

to1 :: forall (a0 :: k0). Rep1 (Const a) a0 -> Const a a0 #

Unbox a => Vector Vector (Const a b) 
Instance details

Defined in Data.Vector.Unboxed.Base

Methods

basicUnsafeFreeze :: PrimMonad m => Mutable Vector (PrimState m) (Const a b) -> m (Vector (Const a b)) #

basicUnsafeThaw :: PrimMonad m => Vector (Const a b) -> m (Mutable Vector (PrimState m) (Const a b)) #

basicLength :: Vector (Const a b) -> Int #

basicUnsafeSlice :: Int -> Int -> Vector (Const a b) -> Vector (Const a b) #

basicUnsafeIndexM :: Monad m => Vector (Const a b) -> Int -> m (Const a b) #

basicUnsafeCopy :: PrimMonad m => Mutable Vector (PrimState m) (Const a b) -> Vector (Const a b) -> m () #

elemseq :: Vector (Const a b) -> Const a b -> b0 -> b0 #

Unbox a => MVector MVector (Const a b) 
Instance details

Defined in Data.Vector.Unboxed.Base

Methods

basicLength :: MVector s (Const a b) -> Int #

basicUnsafeSlice :: Int -> Int -> MVector s (Const a b) -> MVector s (Const a b) #

basicOverlaps :: MVector s (Const a b) -> MVector s (Const a b) -> Bool #

basicUnsafeNew :: PrimMonad m => Int -> m (MVector (PrimState m) (Const a b)) #

basicInitialize :: PrimMonad m => MVector (PrimState m) (Const a b) -> m () #

basicUnsafeReplicate :: PrimMonad m => Int -> Const a b -> m (MVector (PrimState m) (Const a b)) #

basicUnsafeRead :: PrimMonad m => MVector (PrimState m) (Const a b) -> Int -> m (Const a b) #

basicUnsafeWrite :: PrimMonad m => MVector (PrimState m) (Const a b) -> Int -> Const a b -> m () #

basicClear :: PrimMonad m => MVector (PrimState m) (Const a b) -> m () #

basicSet :: PrimMonad m => MVector (PrimState m) (Const a b) -> Const a b -> m () #

basicUnsafeCopy :: PrimMonad m => MVector (PrimState m) (Const a b) -> MVector (PrimState m) (Const a b) -> m () #

basicUnsafeMove :: PrimMonad m => MVector (PrimState m) (Const a b) -> MVector (PrimState m) (Const a b) -> m () #

basicUnsafeGrow :: PrimMonad m => MVector (PrimState m) (Const a b) -> Int -> m (MVector (PrimState m) (Const a b)) #

ToJSON2 (Const :: Type -> Type -> Type) 
Instance details

Defined in Data.Aeson.Types.ToJSON

Methods

liftToJSON2 :: (a -> Value) -> ([a] -> Value) -> (b -> Value) -> ([b] -> Value) -> Const a b -> Value #

liftToJSONList2 :: (a -> Value) -> ([a] -> Value) -> (b -> Value) -> ([b] -> Value) -> [Const a b] -> Value #

liftToEncoding2 :: (a -> Encoding) -> ([a] -> Encoding) -> (b -> Encoding) -> ([b] -> Encoding) -> Const a b -> Encoding #

liftToEncodingList2 :: (a -> Encoding) -> ([a] -> Encoding) -> (b -> Encoding) -> ([b] -> Encoding) -> [Const a b] -> Encoding #

FromJSON2 (Const :: Type -> Type -> Type) 
Instance details

Defined in Data.Aeson.Types.FromJSON

Methods

liftParseJSON2 :: (Value -> Parser a) -> (Value -> Parser [a]) -> (Value -> Parser b) -> (Value -> Parser [b]) -> Value -> Parser (Const a b) #

liftParseJSONList2 :: (Value -> Parser a) -> (Value -> Parser [a]) -> (Value -> Parser b) -> (Value -> Parser [b]) -> Value -> Parser [Const a b] #

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 #

Eq2 (Const :: Type -> Type -> Type)

Since: base-4.9.0.0

Instance details

Defined in Data.Functor.Classes

Methods

liftEq2 :: (a -> b -> Bool) -> (c -> d -> Bool) -> Const a c -> Const b d -> Bool #

Ord2 (Const :: Type -> Type -> Type)

Since: base-4.9.0.0

Instance details

Defined in Data.Functor.Classes

Methods

liftCompare2 :: (a -> b -> Ordering) -> (c -> d -> Ordering) -> Const a c -> Const b d -> Ordering #

Read2 (Const :: Type -> Type -> Type)

Since: base-4.9.0.0

Instance details

Defined in Data.Functor.Classes

Methods

liftReadsPrec2 :: (Int -> ReadS a) -> ReadS [a] -> (Int -> ReadS b) -> ReadS [b] -> Int -> ReadS (Const a b) #

liftReadList2 :: (Int -> ReadS a) -> ReadS [a] -> (Int -> ReadS b) -> ReadS [b] -> ReadS [Const a b] #

liftReadPrec2 :: ReadPrec a -> ReadPrec [a] -> ReadPrec b -> ReadPrec [b] -> ReadPrec (Const a b) #

liftReadListPrec2 :: ReadPrec a -> ReadPrec [a] -> ReadPrec b -> ReadPrec [b] -> ReadPrec [Const a b] #

Show2 (Const :: Type -> Type -> Type)

Since: base-4.9.0.0

Instance details

Defined in Data.Functor.Classes

Methods

liftShowsPrec2 :: (Int -> a -> ShowS) -> ([a] -> ShowS) -> (Int -> b -> ShowS) -> ([b] -> ShowS) -> Int -> Const a b -> ShowS #

liftShowList2 :: (Int -> a -> ShowS) -> ([a] -> ShowS) -> (Int -> b -> ShowS) -> ([b] -> ShowS) -> [Const a b] -> ShowS #

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 #

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) #

Contravariant (Const a :: Type -> Type) 
Instance details

Defined in Data.Functor.Contravariant

Methods

contramap :: (a0 -> b) -> Const a b -> Const a a0 #

(>$) :: b -> Const a b -> Const a a0 #

ToJSON a => ToJSON1 (Const a :: Type -> Type) 
Instance details

Defined in Data.Aeson.Types.ToJSON

Methods

liftToJSON :: (a0 -> Value) -> ([a0] -> Value) -> Const a a0 -> Value #

liftToJSONList :: (a0 -> Value) -> ([a0] -> Value) -> [Const a a0] -> Value #

liftToEncoding :: (a0 -> Encoding) -> ([a0] -> Encoding) -> Const a a0 -> Encoding #

liftToEncodingList :: (a0 -> Encoding) -> ([a0] -> Encoding) -> [Const a a0] -> Encoding #

FromJSON a => FromJSON1 (Const a :: Type -> Type) 
Instance details

Defined in Data.Aeson.Types.FromJSON

Methods

liftParseJSON :: (Value -> Parser a0) -> (Value -> Parser [a0]) -> Value -> Parser (Const a a0) #

liftParseJSONList :: (Value -> Parser a0) -> (Value -> Parser [a0]) -> Value -> Parser [Const a a0] #

Eq a => Eq1 (Const a :: Type -> Type)

Since: base-4.9.0.0

Instance details

Defined in Data.Functor.Classes

Methods

liftEq :: (a0 -> b -> Bool) -> Const a a0 -> Const a b -> Bool #

Ord a => Ord1 (Const a :: Type -> Type)

Since: base-4.9.0.0

Instance details

Defined in Data.Functor.Classes

Methods

liftCompare :: (a0 -> b -> Ordering) -> Const a a0 -> Const a b -> Ordering #

Read a => Read1 (Const a :: Type -> Type)

Since: base-4.9.0.0

Instance details

Defined in Data.Functor.Classes

Methods

liftReadsPrec :: (Int -> ReadS a0) -> ReadS [a0] -> Int -> ReadS (Const a a0) #

liftReadList :: (Int -> ReadS a0) -> ReadS [a0] -> ReadS [Const a a0] #

liftReadPrec :: ReadPrec a0 -> ReadPrec [a0] -> ReadPrec (Const a a0) #

liftReadListPrec :: ReadPrec a0 -> ReadPrec [a0] -> ReadPrec [Const a a0] #

Show a => Show1 (Const a :: Type -> Type)

Since: base-4.9.0.0

Instance details

Defined in Data.Functor.Classes

Methods

liftShowsPrec :: (Int -> a0 -> ShowS) -> ([a0] -> ShowS) -> Int -> Const a a0 -> ShowS #

liftShowList :: (Int -> a0 -> ShowS) -> ([a0] -> ShowS) -> [Const a a0] -> ShowS #

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 #

(Typeable k, Data a, Typeable b) => Data (Const a b)

Since: base-4.10.0.0

Instance details

Defined in Data.Data

Methods

gfoldl :: (forall d b0. Data d => c (d -> b0) -> d -> c b0) -> (forall g. g -> c g) -> Const a b -> c (Const a b) #

gunfold :: (forall b0 r. Data b0 => c (b0 -> r) -> c r) -> (forall r. r -> c r) -> Constr -> c (Const a b) #

toConstr :: Const a b -> Constr #

dataTypeOf :: Const a b -> DataType #

dataCast1 :: Typeable t => (forall d. Data d => c (t d)) -> Maybe (c (Const a b)) #

dataCast2 :: Typeable t => (forall d e. (Data d, Data e) => c (t d e)) -> Maybe (c (Const a b)) #

gmapT :: (forall b0. Data b0 => b0 -> b0) -> Const a b -> Const a b #

gmapQl :: (r -> r' -> r) -> r -> (forall d. Data d => d -> r') -> Const a b -> r #

gmapQr :: forall r r'. (r' -> r -> r) -> r -> (forall d. Data d => d -> r') -> Const a b -> r #

gmapQ :: (forall d. Data d => d -> u) -> Const a b -> [u] #

gmapQi :: Int -> (forall d. Data d => d -> u) -> Const a b -> u #

gmapM :: Monad m => (forall d. Data d => d -> m d) -> Const a b -> m (Const a b) #

gmapMp :: MonadPlus m => (forall d. Data d => d -> m d) -> Const a b -> m (Const a b) #

gmapMo :: MonadPlus m => (forall d. Data d => d -> m d) -> Const a b -> m (Const a b) #

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 getConst field were removed

Since: base-4.8.0.0

Instance details

Defined in Data.Functor.Const

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 getConst 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)

Since: base-4.9.0.0

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 #

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 #

ToJSON a => ToJSON (Const a b) 
Instance details

Defined in Data.Aeson.Types.ToJSON

Methods

toJSON :: Const a b -> Value #

toEncoding :: Const a b -> Encoding #

toJSONList :: [Const a b] -> Value #

toEncodingList :: [Const a b] -> Encoding #

(ToJSON a, ToJSONKey a) => ToJSONKey (Const a b) 
Instance details

Defined in Data.Aeson.Types.ToJSON

FromJSON a => FromJSON (Const a b) 
Instance details

Defined in Data.Aeson.Types.FromJSON

Methods

parseJSON :: Value -> Parser (Const a b) #

parseJSONList :: Value -> Parser [Const a b] #

(FromJSON a, FromJSONKey a) => FromJSONKey (Const a b) 
Instance details

Defined in Data.Aeson.Types.FromJSON

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

Prim a => Prim (Const a b)

Since: primitive-0.6.5.0

Instance details

Defined in Data.Primitive.Types

Methods

sizeOf# :: Const a b -> Int# #

alignment# :: Const a b -> Int# #

indexByteArray# :: ByteArray# -> Int# -> Const a b #

readByteArray# :: MutableByteArray# s -> Int# -> State# s -> (# State# s, Const a b #) #

writeByteArray# :: MutableByteArray# s -> Int# -> Const a b -> State# s -> State# s #

setByteArray# :: MutableByteArray# s -> Int# -> Int# -> Const a b -> State# s -> State# s #

indexOffAddr# :: Addr# -> Int# -> Const a b #

readOffAddr# :: Addr# -> Int# -> State# s -> (# State# s, Const a b #) #

writeOffAddr# :: Addr# -> Int# -> Const a b -> State# s -> State# s #

setOffAddr# :: Addr# -> Int# -> Int# -> Const a b -> State# s -> State# s #

Unbox a => Unbox (Const a b) 
Instance details

Defined in Data.Vector.Unboxed.Base

type Rep1 (Const a :: k -> Type) 
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)))
newtype MVector s (Const a b) 
Instance details

Defined in Data.Vector.Unboxed.Base

newtype MVector s (Const a b) = MV_Const (MVector s a)
type Rep (Const a b) 
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)))
newtype Vector (Const a b) 
Instance details

Defined in Data.Vector.Unboxed.Base

newtype Vector (Const a b) = V_Const (Vector a)

find :: Foldable t => (a -> Bool) -> t a -> Maybe a #

The find function takes a predicate and a structure and returns the leftmost element of the structure matching the predicate, or Nothing if there is no such element.

notElem :: (Foldable t, Eq a) => a -> t a -> Bool infix 4 #

notElem is the negation of elem.

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.

all :: Foldable t => (a -> Bool) -> t a -> Bool #

Determines whether all elements of the structure satisfy the predicate.

any :: Foldable t => (a -> Bool) -> t a -> Bool #

Determines whether any element of the structure satisfies the predicate.

or :: Foldable t => t Bool -> Bool #

or returns the disjunction of a container of Bools. For the result to be False, the container must be finite; True, however, results from a True value finitely far from the left end.

and :: Foldable t => t Bool -> Bool #

and returns the conjunction of a container of Bools. For the result to be True, the container must be finite; False, however, results from a False value finitely far from the left end.

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.

msum :: (Foldable t, MonadPlus m) => t (m a) -> m a #

The sum of a collection of actions, generalizing concat. As of base 4.8.0.0, msum is just asum, specialized to MonadPlus.

asum :: (Foldable t, Alternative f) => t (f a) -> f a #

The sum of a collection of actions, generalizing concat.

>>> asum [Just "Hello", Nothing, Just "World"]
Just "Hello"

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

Evaluate each monadic action in the structure from left to right, and ignore the results. For a version that doesn't ignore the results see sequence.

As of base 4.8.0.0, sequence_ is just sequenceA_, specialized to Monad.

sequenceA_ :: (Foldable t, Applicative f) => t (f a) -> f () #

Evaluate each action in the structure from left to right, and ignore the results. For a version that doesn't ignore the results see sequenceA.

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

forM_ is mapM_ with its arguments flipped. For a version that doesn't ignore the results see forM.

As of base 4.8.0.0, forM_ is just for_, specialized to Monad.

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

Map each element of a structure to a monadic action, evaluate these actions from left to right, and ignore the results. For a version that doesn't ignore the results see mapM.

As of base 4.8.0.0, mapM_ is just traverse_, specialized to Monad.

for_ :: (Foldable t, Applicative f) => t a -> (a -> f b) -> f () #

for_ is traverse_ with its arguments flipped. For a version that doesn't ignore the results see for.

>>> for_ [1..4] print
1
2
3
4

traverse_ :: (Foldable t, Applicative f) => (a -> f b) -> t a -> f () #

Map each element of a structure to an action, evaluate these actions from left to right, and ignore the results. For a version that doesn't ignore the results see traverse.

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.

data Proxy (t :: k) #

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

Instances details
Generic1 (Proxy :: k -> Type)

Since: base-4.6.0.0

Instance details

Defined in GHC.Generics

Associated Types

type Rep1 Proxy :: k -> Type #

Methods

from1 :: forall (a :: k0). Proxy a -> Rep1 Proxy a #

to1 :: forall (a :: k0). 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 #

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 #

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) #

Contravariant (Proxy :: Type -> Type) 
Instance details

Defined in Data.Functor.Contravariant

Methods

contramap :: (a -> b) -> Proxy b -> Proxy a #

(>$) :: b -> Proxy b -> Proxy a #

Representable (Proxy :: Type -> Type) 
Instance details

Defined in Data.Functor.Rep

Associated Types

type Rep Proxy #

Methods

tabulate :: (Rep Proxy -> a) -> Proxy a #

index :: Proxy a -> Rep Proxy -> a #

ToJSON1 (Proxy :: Type -> Type) 
Instance details

Defined in Data.Aeson.Types.ToJSON

Methods

liftToJSON :: (a -> Value) -> ([a] -> Value) -> Proxy a -> Value #

liftToJSONList :: (a -> Value) -> ([a] -> Value) -> [Proxy a] -> Value #

liftToEncoding :: (a -> Encoding) -> ([a] -> Encoding) -> Proxy a -> Encoding #

liftToEncodingList :: (a -> Encoding) -> ([a] -> Encoding) -> [Proxy a] -> Encoding #

FromJSON1 (Proxy :: Type -> Type) 
Instance details

Defined in Data.Aeson.Types.FromJSON

Methods

liftParseJSON :: (Value -> Parser a) -> (Value -> Parser [a]) -> Value -> Parser (Proxy a) #

liftParseJSONList :: (Value -> Parser a) -> (Value -> Parser [a]) -> Value -> Parser [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 #

Eq1 (Proxy :: Type -> Type)

Since: base-4.9.0.0

Instance details

Defined in Data.Functor.Classes

Methods

liftEq :: (a -> b -> Bool) -> Proxy a -> Proxy b -> Bool #

Ord1 (Proxy :: Type -> Type)

Since: base-4.9.0.0

Instance details

Defined in Data.Functor.Classes

Methods

liftCompare :: (a -> b -> Ordering) -> Proxy a -> Proxy b -> Ordering #

Read1 (Proxy :: Type -> Type)

Since: base-4.9.0.0

Instance details

Defined in Data.Functor.Classes

Methods

liftReadsPrec :: (Int -> ReadS a) -> ReadS [a] -> Int -> ReadS (Proxy a) #

liftReadList :: (Int -> ReadS a) -> ReadS [a] -> ReadS [Proxy a] #

liftReadPrec :: ReadPrec a -> ReadPrec [a] -> ReadPrec (Proxy a) #

liftReadListPrec :: ReadPrec a -> ReadPrec [a] -> ReadPrec [Proxy a] #

Show1 (Proxy :: Type -> Type)

Since: base-4.9.0.0

Instance details

Defined in Data.Functor.Classes

Methods

liftShowsPrec :: (Int -> a -> ShowS) -> ([a] -> ShowS) -> Int -> Proxy a -> ShowS #

liftShowList :: (Int -> a -> ShowS) -> ([a] -> ShowS) -> [Proxy a] -> ShowS #

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 #

Data t => Data (Proxy t)

Since: base-4.7.0.0

Instance details

Defined in Data.Data

Methods

gfoldl :: (forall d b. Data d => c (d -> b) -> d -> c b) -> (forall g. g -> c g) -> Proxy t -> c (Proxy t) #

gunfold :: (forall b r. Data b => c (b -> r) -> c r) -> (forall r. r -> c r) -> Constr -> c (Proxy t) #

toConstr :: Proxy t -> Constr #

dataTypeOf :: Proxy t -> DataType #

dataCast1 :: Typeable t0 => (forall d. Data d => c (t0 d)) -> Maybe (c (Proxy t)) #

dataCast2 :: Typeable t0 => (forall d e. (Data d, Data e) => c (t0 d e)) -> Maybe (c (Proxy t)) #

gmapT :: (forall b. Data b => b -> b) -> Proxy t -> Proxy t #

gmapQl :: (r -> r' -> r) -> r -> (forall d. Data d => d -> r') -> Proxy t -> r #

gmapQr :: forall r r'. (r' -> r -> r) -> r -> (forall d. Data d => d -> r') -> Proxy t -> r #

gmapQ :: (forall d. Data d => d -> u) -> Proxy t -> [u] #

gmapQi :: Int -> (forall d. Data d => d -> u) -> Proxy t -> u #

gmapM :: Monad m => (forall d. Data d => d -> m d) -> Proxy t -> m (Proxy t) #

gmapMp :: MonadPlus m => (forall d. Data d => d -> m d) -> Proxy t -> m (Proxy t) #

gmapMo :: MonadPlus m => (forall d. Data d => d -> m d) -> Proxy t -> m (Proxy t) #

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

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)

Since: base-4.6.0.0

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 #

Hashable (Proxy a) 
Instance details

Defined in Data.Hashable.Class

Methods

hashWithSalt :: Int -> Proxy a -> Int #

hash :: Proxy a -> Int #

ToJSON (Proxy a) 
Instance details

Defined in Data.Aeson.Types.ToJSON

FromJSON (Proxy a) 
Instance details

Defined in Data.Aeson.Types.FromJSON

type Rep1 (Proxy :: k -> Type) 
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 :: Type -> Type) 
Instance details

Defined in Data.Functor.Rep

type Rep (Proxy :: Type -> Type) = Void
type Rep (Proxy t) 
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 (a :: k) :~: (b :: k) where infix 4 #

Propositional equality. If a :~: b is inhabited by some terminating value, then the type a is the same as the type b. To use this equality in practice, pattern-match on the a :~: b to get out the Refl constructor; in the body of the pattern-match, the compiler knows that a ~ b.

Since: base-4.7.0.0

Constructors

Refl :: forall k (a :: k). a :~: a 

Instances

Instances details
TestEquality ((:~:) a :: k -> Type)

Since: base-4.7.0.0

Instance details

Defined in Data.Type.Equality

Methods

testEquality :: forall (a0 :: k0) (b :: k0). (a :~: a0) -> (a :~: b) -> Maybe (a0 :~: b) #

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 #

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] #

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 #

(a ~ b, Data a) => Data (a :~: b)

Since: base-4.7.0.0

Instance details

Defined in Data.Data

Methods

gfoldl :: (forall d b0. Data d => c (d -> b0) -> d -> c b0) -> (forall g. g -> c g) -> (a :~: b) -> c (a :~: b) #

gunfold :: (forall b0 r. Data b0 => c (b0 -> r) -> c r) -> (forall r. r -> c r) -> Constr -> c (a :~: b) #

toConstr :: (a :~: b) -> Constr #

dataTypeOf :: (a :~: b) -> DataType #

dataCast1 :: Typeable t => (forall d. Data d => c (t d)) -> Maybe (c (a :~: b)) #

dataCast2 :: Typeable t => (forall d e. (Data d, Data e) => c (t d e)) -> Maybe (c (a :~: b)) #

gmapT :: (forall b0. Data b0 => b0 -> b0) -> (a :~: b) -> a :~: b #

gmapQl :: (r -> r' -> r) -> r -> (forall d. Data d => d -> r') -> (a :~: b) -> r #

gmapQr :: forall r r'. (r' -> r -> r) -> r -> (forall d. Data d => d -> r') -> (a :~: b) -> r #

gmapQ :: (forall d. Data d => d -> u) -> (a :~: b) -> [u] #

gmapQi :: Int -> (forall d. Data d => d -> u) -> (a :~: b) -> u #

gmapM :: Monad m => (forall d. Data d => d -> m d) -> (a :~: b) -> m (a :~: b) #

gmapMp :: MonadPlus m => (forall d. Data d => d -> m d) -> (a :~: b) -> m (a :~: b) #

gmapMo :: MonadPlus m => (forall d. Data d => d -> m d) -> (a :~: b) -> m (a :~: b) #

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 #

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] #

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 #

data (a :: k1) :~~: (b :: k2) where infix 4 #

Kind heterogeneous propositional equality. Like :~:, a :~~: b is inhabited by a terminating value if and only if a is the same type as b.

Since: base-4.10.0.0

Constructors

HRefl :: forall k1 (a :: k1). a :~~: a 

Instances

Instances details
TestEquality ((:~~:) a :: k -> Type)

Since: base-4.10.0.0

Instance details

Defined in Data.Type.Equality

Methods

testEquality :: forall (a0 :: k0) (b :: k0). (a :~~: a0) -> (a :~~: b) -> Maybe (a0 :~: b) #

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 #

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] #

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 #

(Typeable i, Typeable j, Typeable a, Typeable b, a ~~ b) => Data (a :~~: b)

Since: base-4.10.0.0

Instance details

Defined in Data.Data

Methods

gfoldl :: (forall d b0. Data d => c (d -> b0) -> d -> c b0) -> (forall g. g -> c g) -> (a :~~: b) -> c (a :~~: b) #

gunfold :: (forall b0 r. Data b0 => c (b0 -> r) -> c r) -> (forall r. r -> c r) -> Constr -> c (a :~~: b) #

toConstr :: (a :~~: b) -> Constr #

dataTypeOf :: (a :~~: b) -> DataType #

dataCast1 :: Typeable t => (forall d. Data d => c (t d)) -> Maybe (c (a :~~: b)) #

dataCast2 :: Typeable t => (forall d e. (Data d, Data e) => c (t d e)) -> Maybe (c (a :~~: b)) #

gmapT :: (forall b0. Data b0 => b0 -> b0) -> (a :~~: b) -> a :~~: b #

gmapQl :: (r -> r' -> r) -> r -> (forall d. Data d => d -> r') -> (a :~~: b) -> r #

gmapQr :: forall r r'. (r' -> r -> r) -> r -> (forall d. Data d => d -> r') -> (a :~~: b) -> r #

gmapQ :: (forall d. Data d => d -> u) -> (a :~~: b) -> [u] #

gmapQi :: Int -> (forall d. Data d => d -> u) -> (a :~~: b) -> u #

gmapM :: Monad m => (forall d. Data d => d -> m d) -> (a :~~: b) -> m (a :~~: b) #

gmapMp :: MonadPlus m => (forall d. Data d => d -> m d) -> (a :~~: b) -> m (a :~~: b) #

gmapMo :: MonadPlus m => (forall d. Data d => d -> m d) -> (a :~~: b) -> m (a :~~: b) #

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 #

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] #

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 #

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]

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

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

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

Using ApplicativeDo: 'void as' can be understood as the do expression

do as
   pure ()

with an inferred Functor constraint.

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 <$.

Using ApplicativeDo: 'as $> b' can be understood as the do expression

do as
   pure b

with an inferred Functor constraint.

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

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.

Using ApplicativeDo: 'liftA3 f as bs cs' can be understood as the do expression

do a <- as
   b <- bs
   c <- cs
   pure (f a b c)

liftA :: Applicative f => (a -> b) -> f a -> f b #

Lift a function to actions. This function may be used as a value for fmap in a Functor instance.

| Using ApplicativeDo: 'liftA f as' can be understood as the do expression

do a <- as
   pure (f a)

with an inferred Functor constraint, weaker than Applicative.

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

A variant of <*> with the arguments reversed.

Using ApplicativeDo: 'as <**> fs' can be understood as the do expression

do a <- as
   f <- fs
   pure (f a)

decodeUtf8With :: OnDecodeError -> ByteString -> Text #

Decode a ByteString containing UTF-8 encoded text.

NOTE: The replacement character returned by OnDecodeError MUST be within the BMP plane; surrogate code points will automatically be remapped to the replacement char U+FFFD (since 0.11.3.0), whereas code points beyond the BMP will throw an error (since 1.2.3.1); For earlier versions of text using those unsupported code points would result in undefined behavior.

lenientDecode :: OnDecodeError #

Replace an invalid input byte with the Unicode replacement character U+FFFD.

data Vector a #

Boxed vectors, supporting efficient slicing.

Instances

Instances details
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 #

Functor Vector 
Instance details

Defined in Data.Vector

Methods

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

(<$) :: a -> Vector b -> Vector a #

MonadFail Vector

Since: vector-0.12.1.0

Instance details

Defined in Data.Vector

Methods

fail :: String -> Vector 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 #

Foldable Vector 
Instance details

Defined in Data.Vector

Methods

fold :: Monoid m => Vector m -> m #

foldMap :: Monoid m => (a -> m) -> Vector a -> 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 #

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) #

ToJSON1 Vector 
Instance details

Defined in Data.Aeson.Types.ToJSON

Methods

liftToJSON :: (a -> Value) -> ([a] -> Value) -> Vector a -> Value #

liftToJSONList :: (a -> Value) -> ([a] -> Value) -> [Vector a] -> Value #

liftToEncoding :: (a -> Encoding) -> ([a] -> Encoding) -> Vector a -> Encoding #

liftToEncodingList :: (a -> Encoding) -> ([a] -> Encoding) -> [Vector a] -> Encoding #

FromJSON1 Vector 
Instance details

Defined in Data.Aeson.Types.FromJSON

Methods

liftParseJSON :: (Value -> Parser a) -> (Value -> Parser [a]) -> Value -> Parser (Vector a) #

liftParseJSONList :: (Value -> Parser a) -> (Value -> Parser [a]) -> Value -> Parser [Vector 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] #

MonadPlus Vector 
Instance details

Defined in Data.Vector

Methods

mzero :: Vector a #

mplus :: Vector a -> Vector a -> Vector a #

Eq1 Vector 
Instance details

Defined in Data.Vector

Methods

liftEq :: (a -> b -> Bool) -> Vector a -> Vector b -> Bool #

Ord1 Vector 
Instance details

Defined in Data.Vector

Methods

liftCompare :: (a -> b -> Ordering) -> Vector a -> Vector b -> Ordering #

Read1 Vector 
Instance details

Defined in Data.Vector

Methods

liftReadsPrec :: (Int -> ReadS a) -> ReadS [a] -> Int -> ReadS (Vector a) #

liftReadList :: (Int -> ReadS a) -> ReadS [a] -> ReadS [Vector a] #

liftReadPrec :: ReadPrec a -> ReadPrec [a] -> ReadPrec (Vector a) #

liftReadListPrec :: ReadPrec a -> ReadPrec [a] -> ReadPrec [Vector a] #

Show1 Vector 
Instance details

Defined in Data.Vector

Methods

liftShowsPrec :: (Int -> a -> ShowS) -> ([a] -> ShowS) -> Int -> Vector a -> ShowS #

liftShowList :: (Int -> a -> ShowS) -> ([a] -> ShowS) -> [Vector a] -> ShowS #

MonadZip Vector 
Instance details

Defined in Data.Vector

Methods

mzip :: Vector a -> Vector b -> Vector (a, b) #

mzipWith :: (a -> b -> c) -> Vector a -> Vector b -> Vector c #

munzip :: Vector (a, b) -> (Vector a, Vector b) #

NFData1 Vector

Since: vector-0.12.1.0

Instance details

Defined in Data.Vector

Methods

liftRnf :: (a -> ()) -> Vector a -> () #

Vector Vector a 
Instance details

Defined in Data.Vector

Methods

basicUnsafeFreeze :: PrimMonad m => Mutable Vector (PrimState m) a -> m (Vector a) #

basicUnsafeThaw :: PrimMonad m => Vector a -> m (Mutable Vector (PrimState m) a) #

basicLength :: Vector a -> Int #

basicUnsafeSlice :: Int -> Int -> Vector a -> Vector a #

basicUnsafeIndexM :: Monad m => Vector a -> Int -> m a #

basicUnsafeCopy :: PrimMonad m => Mutable Vector (PrimState m) a -> Vector a -> m () #

elemseq :: Vector a -> a -> b -> b #

IsList (Vector a) 
Instance details

Defined in Data.Vector

Associated Types

type Item (Vector a) #

Methods

fromList :: [Item (Vector a)] -> Vector a #

fromListN :: Int -> [Item (Vector a)] -> Vector a #

toList :: Vector a -> [Item (Vector a)] #

Eq a => Eq (Vector a) 
Instance details

Defined in Data.Vector

Methods

(==) :: Vector a -> Vector a -> Bool #

(/=) :: Vector a -> Vector a -> Bool #

Data a => Data (Vector a) 
Instance details

Defined in Data.Vector

Methods

gfoldl :: (forall d b. Data d => c (d -> b) -> d -> c b) -> (forall g. g -> c g) -> Vector a -> c (Vector a) #

gunfold :: (forall b r. Data b => c (b -> r) -> c r) -> (forall r. r -> c r) -> Constr -> c (Vector a) #

toConstr :: Vector a -> Constr #

dataTypeOf :: Vector a -> DataType #

dataCast1 :: Typeable t => (forall d. Data d => c (t d)) -> Maybe (c (Vector a)) #

dataCast2 :: Typeable t => (forall d e. (Data d, Data e) => c (t d e)) -> Maybe (c (Vector a)) #

gmapT :: (forall b. Data b => b -> b) -> Vector a -> Vector a #

gmapQl :: (r -> r' -> r) -> r -> (forall d. Data d => d -> r') -> Vector a -> r #

gmapQr :: forall r r'. (r' -> r -> r) -> r -> (forall d. Data d => d -> r') -> Vector a -> r #

gmapQ :: (forall d. Data d => d -> u) -> Vector a -> [u] #

gmapQi :: Int -> (forall d. Data d => d -> u) -> Vector a -> u #

gmapM :: Monad m => (forall d. Data d => d -> m d) -> Vector a -> m (Vector a) #

gmapMp :: MonadPlus m => (forall d. Data d => d -> m d) -> Vector a -> m (Vector a) #

gmapMo :: MonadPlus m => (forall d. Data d => d -> m d) -> Vector a -> m (Vector 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 #

Read a => Read (Vector a) 
Instance details

Defined in Data.Vector

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 #

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 #

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 #

ToJSON a => ToJSON (Vector a) 
Instance details

Defined in Data.Aeson.Types.ToJSON

FromJSON a => FromJSON (Vector a) 
Instance details

Defined in Data.Aeson.Types.FromJSON

NFData a => NFData (Vector a) 
Instance details

Defined in Data.Vector

Methods

rnf :: Vector a -> () #

type Mutable Vector 
Instance details

Defined in Data.Vector

type Item (Vector a) 
Instance details

Defined in Data.Vector

type Item (Vector a) = a
type Rep (Vector Vector n) 
Instance details

Defined in Data.Vector.Generic.Sized

type Rep (Vector Vector n) = Finite n

data Text #

A space efficient, packed, unboxed Unicode text type.

Instances

Instances details
Hashable Text 
Instance details

Defined in Data.Hashable.Class

Methods

hashWithSalt :: Int -> Text -> Int #

hash :: Text -> Int #

ToJSON Text 
Instance details

Defined in Data.Aeson.Types.ToJSON

KeyValue Object

Constructs a singleton HashMap. For calling functions that demand an Object for constructing objects. To be used in conjunction with mconcat. Prefer to use object where possible.

Instance details

Defined in Data.Aeson.Types.ToJSON

Methods

(.=) :: ToJSON v => Text -> v -> Object #

KeyValue Pair 
Instance details

Defined in Data.Aeson.Types.ToJSON

Methods

(.=) :: ToJSON v => Text -> v -> Pair #

ToJSONKey Text 
Instance details

Defined in Data.Aeson.Types.ToJSON

FromJSON Text 
Instance details

Defined in Data.Aeson.Types.FromJSON

FromJSONKey Text 
Instance details

Defined in Data.Aeson.Types.FromJSON

Chunk Text 
Instance details

Defined in Data.Attoparsec.Internal.Types

Associated Types

type ChunkElem Text #

FromSql Text Source # 
Instance details

Defined in Preql.FromSql.Instances

Associated Types

type Width Text :: Nat Source #

FromSqlField Text Source # 
Instance details

Defined in Preql.FromSql.Instances

ToSql Text Source # 
Instance details

Defined in Preql.Wire.ToSql

ToSqlField Text Source # 
Instance details

Defined in Preql.Wire.ToSql

MonadError Text BinaryParser 
Instance details

Defined in BinaryParser

FromPairs Value (DList Pair) 
Instance details

Defined in Data.Aeson.Types.ToJSON

Methods

fromPairs :: DList Pair -> Value

v ~ Value => KeyValuePair v (DList Pair) 
Instance details

Defined in Data.Aeson.Types.ToJSON

Methods

pair :: String -> v -> DList Pair

type State Text 
Instance details

Defined in Data.Attoparsec.Internal.Types

type State Text = Buffer
type ChunkElem Text 
Instance details

Defined in Data.Attoparsec.Internal.Types

type Item Text 
Instance details

Defined in Data.Text

type Item Text = Char
type Width Text Source # 
Instance details

Defined in Preql.FromSql.Instances

type Width Text = 1

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

Instances details
Eq ByteString 
Instance details

Defined in Data.ByteString.Internal

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 :: forall r r'. (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

Read ByteString 
Instance details

Defined in Data.ByteString.Internal

Show ByteString 
Instance details

Defined in Data.ByteString.Internal

IsString ByteString 
Instance details

Defined in Data.ByteString.Internal

Semigroup ByteString 
Instance details

Defined in Data.ByteString.Internal

Monoid ByteString 
Instance details

Defined in Data.ByteString.Internal

Hashable ByteString 
Instance details

Defined in Data.Hashable.Class

Chunk ByteString 
Instance details

Defined in Data.Attoparsec.Internal.Types

Associated Types

type ChunkElem ByteString #

Serializable ByteString 
Instance details

Defined in Data.Serializer

Methods

put :: Serializer s => ByteString -> s #

RestSerializable ByteString 
Instance details

Defined in Data.Serializer

Methods

putRest :: Serializer s => ByteString -> s #

Deserializable ByteString 
Instance details

Defined in Data.Deserializer

Methods

get :: Deserializer μ => μ ByteString #

RestDeserializable ByteString 
Instance details

Defined in Data.Deserializer

Methods

getRest :: Deserializer μ => μ ByteString #

NFData ByteString 
Instance details

Defined in Data.ByteString.Internal

Methods

rnf :: ByteString -> () #

FromSql ByteString Source # 
Instance details

Defined in Preql.FromSql.Instances

Associated Types

type Width ByteString :: Nat Source #

FromSqlField ByteString Source #

If you want to encode some more specific Haskell type via JSON, it is more efficient to use encode and jsonb_bytes directly, rather than this instance.

Instance details

Defined in Preql.FromSql.Instances

ToSql ByteString Source # 
Instance details

Defined in Preql.Wire.ToSql

ToSqlField ByteString Source #

If you want to encode some more specific Haskell type via JSON, it is more efficient to use encode and jsonb_bytes directly, rather than this instance.

Instance details

Defined in Preql.Wire.ToSql

type State ByteString 
Instance details

Defined in Data.Attoparsec.Internal.Types

type State ByteString = Buffer
type ChunkElem ByteString 
Instance details

Defined in Data.Attoparsec.Internal.Types

type Width ByteString Source # 
Instance details

Defined in Preql.FromSql.Instances

type Width ByteString = 1