| Copyright | (c) 2016 Stephen Diehl (c) 2016-2018 Serokell (c) 2018-2020 Kowainik |
|---|---|
| License | MIT |
| Maintainer | Kowainik <xrom.xkov@gmail.com> |
| Stability | Stable |
| Portability | Portable |
| Safe Haskell | Trustworthy |
| Language | Haskell2010 |
Relude.Base
Description
Reexports from Data.* and GHC.* modules of
base package.
Synopsis
- data Char
- chr :: Int -> Char
- class Eq a where
- class Eq a => Ord a where
- data Ordering
- comparing :: Ord a => (b -> a) -> b -> b -> Ordering
- newtype Down a = Down a
- data IO a
- data Handle
- withFile :: FilePath -> IOMode -> (Handle -> IO r) -> IO r
- stderr :: Handle
- stdin :: Handle
- stdout :: Handle
- type FilePath = String
- data IOMode
- coerce :: Coercible a b => a -> b
- class a ~R# b => Coercible (a :: k) (b :: k)
- type Type = Type
- data Constraint
- data Proxy (t :: k) = Proxy
- class Typeable (a :: k)
- vacuous :: Functor f => f Void -> f a
- absurd :: Void -> a
- data Void
- seq :: a -> b -> b
- asTypeOf :: a -> a -> a
- ($!) :: forall (r :: RuntimeRep) a (b :: TYPE r). (a -> b) -> a -> b
- ord :: Char -> Int
- class Bounded a where
- class Enum a where
- succ :: a -> a
- pred :: a -> a
- toEnum :: Int -> a
- fromEnum :: a -> Int
- enumFrom :: a -> [a]
- enumFromThen :: a -> a -> [a]
- enumFromTo :: a -> a -> [a]
- enumFromThenTo :: a -> a -> a -> [a]
- boundedEnumFromThen :: (Enum a, Bounded a) => a -> a -> [a]
- boundedEnumFrom :: (Enum a, Bounded a) => a -> [a]
- class Generic a
- class Show a
- class KnownNat (n :: Nat)
- data Nat
- type family CmpNat (a :: Nat) (b :: Nat) :: Ordering where ...
- someNatVal :: Natural -> SomeNat
- natVal :: forall (n :: Nat) proxy. KnownNat n => proxy n -> Natural
- data SomeNat = KnownNat n => SomeNat (Proxy n)
- class IsLabel (x :: Symbol) a where
- fromLabel :: a
- showStackTrace :: IO (Maybe String)
- getStackTrace :: IO (Maybe [Location])
- data CallStack
- withFrozenCallStack :: HasCallStack => (HasCallStack => a) -> a
- callStack :: HasCallStack => CallStack
- prettyCallStack :: CallStack -> String
- prettySrcLoc :: SrcLoc -> String
- currentCallStack :: IO [String]
- getCallStack :: CallStack -> [([Char], SrcLoc)]
- type HasCallStack = ?callStack :: CallStack
Base types
The character type Char is an enumeration whose values represent
Unicode (or equivalently ISO/IEC 10646) code points (i.e. characters, see
http://www.unicode.org/ for details). This set extends the ISO 8859-1
(Latin-1) character set (the first 256 characters), which is itself an extension
of the ASCII character set (the first 128 characters). A character literal in
Haskell has type Char.
To convert a Char to or from the corresponding Int value defined
by Unicode, use toEnum and fromEnum from the
Enum class respectively (or equivalently ord and
chr).
Instances
| Bounded Char | Since: base-2.1 |
| Enum Char | Since: base-2.1 |
| Eq Char | |
| Data Char | Since: base-4.0.0.0 |
Defined in Data.Data Methods gfoldl :: (forall d b. Data d => c (d -> b) -> d -> c b) -> (forall g. g -> c g) -> Char -> c Char # gunfold :: (forall b r. Data b => c (b -> r) -> c r) -> (forall r. r -> c r) -> Constr -> c Char # dataTypeOf :: Char -> DataType # dataCast1 :: Typeable t => (forall d. Data d => c (t d)) -> Maybe (c Char) # dataCast2 :: Typeable t => (forall d e. (Data d, Data e) => c (t d e)) -> Maybe (c Char) # gmapT :: (forall b. Data b => b -> b) -> Char -> Char # gmapQl :: (r -> r' -> r) -> r -> (forall d. Data d => d -> r') -> Char -> r # gmapQr :: forall r r'. (r' -> r -> r) -> r -> (forall d. Data d => d -> r') -> Char -> r # gmapQ :: (forall d. Data d => d -> u) -> Char -> [u] # gmapQi :: Int -> (forall d. Data d => d -> u) -> Char -> u # gmapM :: Monad m => (forall d. Data d => d -> m d) -> Char -> m Char # gmapMp :: MonadPlus m => (forall d. Data d => d -> m d) -> Char -> m Char # gmapMo :: MonadPlus m => (forall d. Data d => d -> m d) -> Char -> m Char # | |
| Ord Char | |
| Read Char | Since: base-2.1 |
| Show Char | Since: base-2.1 |
| Ix Char | Since: base-2.1 |
| Lift Char | |
| NFData Char | |
Defined in Control.DeepSeq | |
| Hashable Char | |
Defined in Data.Hashable.Class | |
| ErrorList Char | |
Defined in Control.Monad.Trans.Error | |
| ToString String Source # | |
| ToLText String Source # | |
| ToText String Source # | |
| ConvertUtf8 String ShortByteString Source # | Since: 0.6.0.0 |
Defined in Relude.String.Conversion Methods encodeUtf8 :: String -> ShortByteString Source # decodeUtf8 :: ShortByteString -> String Source # decodeUtf8Strict :: ShortByteString -> Either UnicodeException String Source # | |
| ConvertUtf8 String ByteString Source # | |
Defined in Relude.String.Conversion Methods encodeUtf8 :: String -> ByteString Source # decodeUtf8 :: ByteString -> String Source # decodeUtf8Strict :: ByteString -> Either UnicodeException String Source # | |
| ConvertUtf8 String LByteString Source # | Converting |
Defined in Relude.String.Conversion Methods encodeUtf8 :: String -> LByteString Source # decodeUtf8 :: LByteString -> String Source # decodeUtf8Strict :: LByteString -> Either UnicodeException String Source # | |
| Generic1 (URec Char :: k -> Type) | Since: base-4.9.0.0 |
| Functor (URec Char :: Type -> Type) | Since: base-4.9.0.0 |
| Foldable (URec Char :: Type -> Type) | Since: base-4.9.0.0 |
Defined in Data.Foldable Methods fold :: Monoid m => URec Char m -> m # foldMap :: Monoid m => (a -> m) -> URec Char a -> m # foldMap' :: Monoid m => (a -> m) -> URec Char a -> m # foldr :: (a -> b -> b) -> b -> URec Char a -> b # foldr' :: (a -> b -> b) -> b -> URec Char a -> b # foldl :: (b -> a -> b) -> b -> URec Char a -> b # foldl' :: (b -> a -> b) -> b -> URec Char a -> b # foldr1 :: (a -> a -> a) -> URec Char a -> a # foldl1 :: (a -> a -> a) -> URec Char a -> a # toList :: URec Char a -> [a] # length :: URec Char a -> Int # elem :: Eq a => a -> URec Char a -> Bool # maximum :: Ord a => URec Char a -> a # minimum :: Ord a => URec Char a -> a # | |
| Traversable (URec Char :: Type -> Type) | Since: base-4.9.0.0 |
Defined in Data.Traversable | |
| Eq (URec Char p) | Since: base-4.9.0.0 |
| Ord (URec Char p) | Since: base-4.9.0.0 |
Defined in GHC.Generics | |
| Show (URec Char p) | Since: base-4.9.0.0 |
| Generic (URec Char p) | Since: base-4.9.0.0 |
| data URec Char (p :: k) | Used for marking occurrences of Since: base-4.9.0.0 |
| type Rep1 (URec Char :: k -> Type) | |
Defined in GHC.Generics | |
| type Rep (URec Char p) | |
Defined in GHC.Generics | |
Base type classes
The Eq class defines equality (==) and inequality (/=).
All the basic datatypes exported by the Prelude are instances of Eq,
and Eq may be derived for any datatype whose constituents are also
instances of Eq.
The Haskell Report defines no laws for Eq. However, == is customarily
expected to implement an equivalence relationship where two values comparing
equal are indistinguishable by "public" functions, with a "public" function
being one not allowing to see implementation details. For example, for a
type representing non-normalised natural numbers modulo 100, a "public"
function doesn't make the difference between 1 and 201. It is expected to
have the following properties:
Instances
| Eq Bool | |
| Eq Char | |
| Eq Double | Note that due to the presence of
Also note that
|
| Eq Float | Note that due to the presence of
Also note that
|
| Eq Int | |
| Eq Int8 | Since: base-2.1 |
| Eq Int16 | Since: base-2.1 |
| Eq Int32 | Since: base-2.1 |
| Eq Int64 | Since: base-2.1 |
| Eq Integer | |
| Eq Natural | Since: base-4.8.0.0 |
| Eq Ordering | |
| Eq Word | |
| Eq Word8 | Since: base-2.1 |
| Eq Word16 | Since: base-2.1 |
| Eq Word32 | Since: base-2.1 |
| Eq Word64 | Since: base-2.1 |
| Eq SomeTypeRep | |
Defined in Data.Typeable.Internal | |
| Eq Exp | |
| Eq Match | |
| Eq Clause | |
| Eq Pat | |
| Eq Type | |
| Eq Dec | |
| Eq Name | |
| Eq FunDep | |
| Eq InjectivityAnn | |
Defined in Language.Haskell.TH.Syntax Methods (==) :: InjectivityAnn -> InjectivityAnn -> Bool # (/=) :: InjectivityAnn -> InjectivityAnn -> Bool # | |
| Eq Overlap | |
| Eq () | |
| Eq TyCon | |
| Eq Module | |
| Eq TrName | |
| Eq Handle | Since: base-4.1.0.0 |
| Eq BigNat | |
| Eq Void | Since: base-4.8.0.0 |
| Eq SpecConstrAnnotation | Since: base-4.3.0.0 |
Defined in GHC.Exts Methods (==) :: SpecConstrAnnotation -> SpecConstrAnnotation -> Bool # (/=) :: SpecConstrAnnotation -> SpecConstrAnnotation -> Bool # | |
| Eq Constr | Equality of constructors Since: base-4.0.0.0 |
| Eq DataRep | Since: base-4.0.0.0 |
| Eq ConstrRep | Since: base-4.0.0.0 |
| Eq Fixity | Since: base-4.0.0.0 |
| Eq Unique | |
| Eq Version | Since: base-2.1 |
| Eq ThreadId | Since: base-4.2.0.0 |
| Eq BlockReason | Since: base-4.3.0.0 |
Defined in GHC.Conc.Sync | |
| Eq ThreadStatus | Since: base-4.3.0.0 |
Defined in GHC.Conc.Sync | |
| Eq AsyncException | Since: base-4.2.0.0 |
Defined in GHC.IO.Exception Methods (==) :: AsyncException -> AsyncException -> Bool # (/=) :: AsyncException -> AsyncException -> Bool # | |
| Eq ArrayException | Since: base-4.2.0.0 |
Defined in GHC.IO.Exception Methods (==) :: ArrayException -> ArrayException -> Bool # (/=) :: ArrayException -> ArrayException -> Bool # | |
| Eq ExitCode | |
| Eq IOErrorType | Since: base-4.1.0.0 |
Defined in GHC.IO.Exception | |
| Eq BufferMode | Since: base-4.2.0.0 |
Defined in GHC.IO.Handle.Types | |
| Eq Newline | Since: base-4.2.0.0 |
| Eq NewlineMode | Since: base-4.2.0.0 |
Defined in GHC.IO.Handle.Types | |
| Eq MaskingState | Since: base-4.3.0.0 |
Defined in GHC.IO | |
| Eq IOException | Since: base-4.1.0.0 |
Defined in GHC.IO.Exception | |
| Eq ErrorCall | Since: base-4.7.0.0 |
| Eq ArithException | Since: base-3.0 |
Defined in GHC.Exception.Type Methods (==) :: ArithException -> ArithException -> Bool # (/=) :: ArithException -> ArithException -> Bool # | |
| Eq All | Since: base-2.1 |
| Eq Any | Since: base-2.1 |
| Eq Fixity | Since: base-4.6.0.0 |
| Eq Associativity | Since: base-4.6.0.0 |
Defined in GHC.Generics Methods (==) :: Associativity -> Associativity -> Bool # (/=) :: Associativity -> Associativity -> Bool # | |
| Eq SourceUnpackedness | Since: base-4.9.0.0 |
Defined in GHC.Generics Methods (==) :: SourceUnpackedness -> SourceUnpackedness -> Bool # (/=) :: SourceUnpackedness -> SourceUnpackedness -> Bool # | |
| Eq SourceStrictness | Since: base-4.9.0.0 |
Defined in GHC.Generics Methods (==) :: SourceStrictness -> SourceStrictness -> Bool # (/=) :: SourceStrictness -> SourceStrictness -> Bool # | |
| Eq DecidedStrictness | Since: base-4.9.0.0 |
Defined in GHC.Generics Methods (==) :: DecidedStrictness -> DecidedStrictness -> Bool # (/=) :: DecidedStrictness -> DecidedStrictness -> Bool # | |
| Eq SomeSymbol | Since: base-4.7.0.0 |
Defined in GHC.TypeLits | |
| Eq SomeNat | Since: base-4.7.0.0 |
| Eq CChar | |
| Eq CSChar | |
| Eq CUChar | |
| Eq CShort | |
| Eq CUShort | |
| Eq CInt | |
| Eq CUInt | |
| Eq CLong | |
| Eq CULong | |
| Eq CLLong | |
| Eq CULLong | |
| Eq CBool | |
| Eq CFloat | |
| Eq CDouble | |
| Eq CPtrdiff | |
| Eq CSize | |
| Eq CWchar | |
| Eq CSigAtomic | |
Defined in Foreign.C.Types | |
| Eq CClock | |
| Eq CTime | |
| Eq CUSeconds | |
| Eq CSUSeconds | |
Defined in Foreign.C.Types | |
| Eq CIntPtr | |
| Eq CUIntPtr | |
| Eq CIntMax | |
| Eq CUIntMax | |
| Eq WordPtr | |
| Eq IntPtr | |
| Eq IOMode | Since: base-4.2.0.0 |
| Eq Fingerprint | Since: base-4.4.0.0 |
Defined in GHC.Fingerprint.Type | |
| Eq Lexeme | Since: base-2.1 |
| Eq Number | Since: base-4.6.0.0 |
| Eq SrcLoc | Since: base-4.9.0.0 |
| Eq ShortByteString | |
Defined in Data.ByteString.Short.Internal Methods (==) :: ShortByteString -> ShortByteString -> Bool # (/=) :: ShortByteString -> ShortByteString -> Bool # | |
| Eq ByteString | |
Defined in Data.ByteString.Lazy.Internal | |
| Eq ByteString | |
Defined in Data.ByteString.Internal | |
| Eq IntSet | |
| Eq Extension | |
| Eq ForeignSrcLang | |
Defined in GHC.ForeignSrcLang.Type Methods (==) :: ForeignSrcLang -> ForeignSrcLang -> Bool # (/=) :: ForeignSrcLang -> ForeignSrcLang -> Bool # | |
| Eq ModName | |
| Eq PkgName | |
| Eq Module | |
| Eq OccName | |
| Eq NameFlavour | |
Defined in Language.Haskell.TH.Syntax | |
| Eq NameSpace | |
| Eq Loc | |
| Eq Info | |
| Eq ModuleInfo | |
Defined in Language.Haskell.TH.Syntax | |
| Eq Fixity | |
| Eq FixityDirection | |
Defined in Language.Haskell.TH.Syntax Methods (==) :: FixityDirection -> FixityDirection -> Bool # (/=) :: FixityDirection -> FixityDirection -> Bool # | |
| Eq Lit | |
| Eq Body | |
| Eq Guard | |
| Eq Stmt | |
| Eq Range | |
| Eq DerivClause | |
Defined in Language.Haskell.TH.Syntax | |
| Eq DerivStrategy | |
Defined in Language.Haskell.TH.Syntax Methods (==) :: DerivStrategy -> DerivStrategy -> Bool # (/=) :: DerivStrategy -> DerivStrategy -> Bool # | |
| Eq TypeFamilyHead | |
Defined in Language.Haskell.TH.Syntax Methods (==) :: TypeFamilyHead -> TypeFamilyHead -> Bool # (/=) :: TypeFamilyHead -> TypeFamilyHead -> Bool # | |
| Eq TySynEqn | |
| Eq Foreign | |
| Eq Callconv | |
| Eq Safety | |
| Eq Pragma | |
| Eq Inline | |
| Eq RuleMatch | |
| Eq Phases | |
| Eq RuleBndr | |
| Eq AnnTarget | |
| Eq SourceUnpackedness | |
Defined in Language.Haskell.TH.Syntax Methods (==) :: SourceUnpackedness -> SourceUnpackedness -> Bool # (/=) :: SourceUnpackedness -> SourceUnpackedness -> Bool # | |
| Eq SourceStrictness | |
Defined in Language.Haskell.TH.Syntax Methods (==) :: SourceStrictness -> SourceStrictness -> Bool # (/=) :: SourceStrictness -> SourceStrictness -> Bool # | |
| Eq DecidedStrictness | |
Defined in Language.Haskell.TH.Syntax Methods (==) :: DecidedStrictness -> DecidedStrictness -> Bool # (/=) :: DecidedStrictness -> DecidedStrictness -> Bool # | |
| Eq Con | |
| Eq Bang | |
| Eq PatSynDir | |
| Eq PatSynArgs | |
Defined in Language.Haskell.TH.Syntax | |
| Eq TyVarBndr | |
| Eq FamilyResultSig | |
Defined in Language.Haskell.TH.Syntax Methods (==) :: FamilyResultSig -> FamilyResultSig -> Bool # (/=) :: FamilyResultSig -> FamilyResultSig -> Bool # | |
| Eq TyLit | |
| Eq Role | |
| Eq AnnLookup | |
| Eq UnicodeException | |
Defined in Data.Text.Encoding.Error Methods (==) :: UnicodeException -> UnicodeException -> Bool # (/=) :: UnicodeException -> UnicodeException -> Bool # | |
| Eq CodePoint | |
| Eq DecoderState | |
| Eq Undefined Source # | |
| Eq a => Eq [a] | |
| Eq a => Eq (Maybe a) | Since: base-2.1 |
| Eq a => Eq (Ratio a) | Since: base-2.1 |
| Eq (Ptr a) | Since: base-2.1 |
| Eq (FunPtr a) | |
| Eq p => Eq (Par1 p) | Since: base-4.7.0.0 |
| Eq a => Eq (Complex a) | Since: base-2.1 |
| Eq (Fixed a) | Since: base-2.1 |
| Eq a => Eq (Min a) | Since: base-4.9.0.0 |
| Eq a => Eq (Max a) | Since: base-4.9.0.0 |
| Eq a => Eq (First a) | Since: base-4.9.0.0 |
| Eq a => Eq (Last a) | Since: base-4.9.0.0 |
| Eq m => Eq (WrappedMonoid m) | Since: base-4.9.0.0 |
Defined in Data.Semigroup Methods (==) :: WrappedMonoid m -> WrappedMonoid m -> Bool # (/=) :: WrappedMonoid m -> WrappedMonoid m -> Bool # | |
| Eq a => Eq (Option a) | Since: base-4.9.0.0 |
| Eq (StableName a) | Since: base-2.1 |
Defined in GHC.StableName | |
| Eq a => Eq (ZipList a) | Since: base-4.7.0.0 |
| Eq a => Eq (Identity a) | Since: base-4.8.0.0 |
| Eq (TVar a) | Since: base-4.8.0.0 |
| Eq (IORef a) | Pointer equality. Since: base-4.0.0.0 |
| Eq a => Eq (First a) | Since: base-2.1 |
| Eq a => Eq (Last a) | Since: base-2.1 |
| Eq a => Eq (Dual a) | Since: base-2.1 |
| Eq a => Eq (Sum a) | Since: base-2.1 |
| Eq a => Eq (Product a) | Since: base-2.1 |
| Eq a => Eq (Down a) | Since: base-4.6.0.0 |
| Eq (MVar a) | Since: base-4.1.0.0 |
| Eq a => Eq (NonEmpty a) | Since: base-4.9.0.0 |
| Eq a => Eq (IntMap a) | |
| Eq a => Eq (Tree a) | |
| Eq a => Eq (Seq a) | |
| Eq a => Eq (ViewL a) | |
| Eq a => Eq (ViewR a) | |
| Eq a => Eq (Set a) | |
| Eq a => Eq (Hashed a) | Uses precomputed hash to detect inequality faster |
| Eq a => Eq (HashSet a) | |
| Eq (TMVar a) | |
| (Eq a, Eq b) => Eq (Either a b) | Since: base-2.1 |
| Eq (V1 p) | Since: base-4.9.0.0 |
| Eq (U1 p) | Since: base-4.9.0.0 |
| Eq (TypeRep a) | Since: base-2.1 |
| (Eq a, Eq b) => Eq (a, b) | |
| (Ix i, Eq e) => Eq (Array i e) | Since: base-2.1 |
| Eq a => Eq (Arg a b) | Since: base-4.9.0.0 |
| Eq (Proxy s) | Since: base-4.7.0.0 |
| Eq (STRef s a) | Pointer equality. Since: base-2.1 |
| (Eq k, Eq a) => Eq (Map k a) | |
| (Eq k, Eq v) => Eq (Leaf k v) | |
| (Eq k, Eq v) => Eq (HashMap k v) | |
| (Eq1 m, Eq a) => Eq (MaybeT m a) | |
| (Eq e, Eq a) => Eq (Validation e a) Source # | |
Defined in Relude.Extra.Validation Methods (==) :: Validation e a -> Validation e a -> Bool # (/=) :: Validation e a -> Validation e a -> Bool # | |
| Eq (f p) => Eq (Rec1 f p) | Since: base-4.7.0.0 |
| Eq (URec (Ptr ()) p) | Since: base-4.9.0.0 |
| Eq (URec Char p) | Since: base-4.9.0.0 |
| Eq (URec Double p) | Since: base-4.9.0.0 |
| Eq (URec Float p) | |
| Eq (URec Int p) | Since: base-4.9.0.0 |
| Eq (URec Word p) | Since: base-4.9.0.0 |
| (Eq a, Eq b, Eq c) => Eq (a, b, c) | |
| Eq (STArray s i e) | Since: base-2.1 |
| Eq a => Eq (Const a b) | Since: base-4.9.0.0 |
| Eq (f a) => Eq (Ap f a) | Since: base-4.12.0.0 |
| Eq (f a) => Eq (Alt f a) | Since: base-4.8.0.0 |
| Eq (a :~: b) | Since: base-4.7.0.0 |
| (Eq1 f, Eq a) => Eq (IdentityT f a) | |
| (Eq e, Eq1 m, Eq a) => Eq (ErrorT e m a) | |
| (Eq e, Eq1 m, Eq a) => Eq (ExceptT e m a) | |
| Eq c => Eq (K1 i c p) | Since: base-4.7.0.0 |
| (Eq (f p), Eq (g p)) => Eq ((f :+: g) p) | Since: base-4.7.0.0 |
| (Eq (f p), Eq (g p)) => Eq ((f :*: g) p) | Since: base-4.7.0.0 |
| (Eq a, Eq b, Eq c, Eq d) => Eq (a, b, c, d) | |
| (Eq1 f, Eq1 g, Eq a) => Eq (Product f g a) | Since: base-4.9.0.0 |
| (Eq1 f, Eq1 g, Eq a) => Eq (Sum f g a) | Since: base-4.9.0.0 |
| Eq (a :~~: b) | Since: base-4.10.0.0 |
| Eq (f p) => Eq (M1 i c f p) | Since: base-4.7.0.0 |
| Eq (f (g p)) => Eq ((f :.: g) p) | Since: base-4.7.0.0 |
| (Eq a, Eq b, Eq c, Eq d, Eq e) => Eq (a, b, c, d, e) | |
| (Eq1 f, Eq1 g, Eq a) => Eq (Compose f g a) | Since: base-4.9.0.0 |
| (Eq a, Eq b, Eq c, Eq d, Eq e, Eq f) => Eq (a, b, c, d, e, f) | |
| (Eq a, Eq b, Eq c, Eq d, Eq e, Eq f, Eq g) => Eq (a, b, c, d, e, f, g) | |
| (Eq a, Eq b, Eq c, Eq d, Eq e, Eq f, Eq g, Eq h) => Eq (a, b, c, d, e, f, g, h) | |
| (Eq a, Eq b, Eq c, Eq d, Eq e, Eq f, Eq g, Eq h, Eq i) => Eq (a, b, c, d, e, f, g, h, i) | |
| (Eq a, Eq b, Eq c, Eq d, Eq e, Eq f, Eq g, Eq h, Eq i, Eq j) => Eq (a, b, c, d, e, f, g, h, i, j) | |
| (Eq a, Eq b, Eq c, Eq d, Eq e, Eq f, Eq g, Eq h, Eq i, Eq j, Eq k) => Eq (a, b, c, d, e, f, g, h, i, j, k) | |
| (Eq a, Eq b, Eq c, Eq d, Eq e, Eq f, Eq g, Eq h, Eq i, Eq j, Eq k, Eq l) => Eq (a, b, c, d, e, f, g, h, i, j, k, l) | |
| (Eq a, Eq b, Eq c, Eq d, Eq e, Eq f, Eq g, Eq h, Eq i, Eq j, Eq k, Eq l, Eq m) => Eq (a, b, c, d, e, f, g, h, i, j, k, l, m) | |
| (Eq a, Eq b, Eq c, Eq d, Eq e, Eq f, Eq g, Eq h, Eq i, Eq j, Eq k, Eq l, Eq m, Eq n) => Eq (a, b, c, d, e, f, g, h, i, j, k, l, m, n) | |
| (Eq a, Eq b, Eq c, Eq d, Eq e, Eq f, Eq g, Eq h, Eq i, Eq j, Eq k, Eq l, Eq m, Eq n, Eq o) => Eq (a, b, c, d, e, f, g, h, i, j, k, l, m, n, o) | |
The Ord class is used for totally ordered datatypes.
Instances of Ord can be derived for any user-defined datatype whose
constituent types are in Ord. The declared order of the constructors in
the data declaration determines the ordering in derived Ord instances. The
Ordering datatype allows a single comparison to determine the precise
ordering of two objects.
The Haskell Report defines no laws for Ord. However, <= is customarily
expected to implement a non-strict partial order and have the following
properties:
- Transitivity
- if
x <= y && y <= z=True, thenx <= z=True - Reflexivity
x <= x=True- Antisymmetry
- if
x <= y && y <= x=True, thenx == y=True
Note that the following operator interactions are expected to hold:
x >= y=y <= xx < y=x <= y && x /= yx > y=y < xx < y=compare x y == LTx > y=compare x y == GTx == y=compare x y == EQmin x y == if x <= y then x else y=Truemax x y == if x >= y then x else y=True
Minimal complete definition: either compare or <=.
Using compare can be more efficient for complex types.
Methods
compare :: a -> a -> Ordering #
(<) :: a -> a -> Bool infix 4 #
(<=) :: a -> a -> Bool infix 4 #
(>) :: a -> a -> Bool infix 4 #
Instances
| Ord Bool | |
| Ord Char | |
| Ord Double | Note that due to the presence of
Also note that, due to the same,
|
| Ord Float | Note that due to the presence of
Also note that, due to the same,
|
| Ord Int | |
| Ord Int8 | Since: base-2.1 |
| Ord Int16 | Since: base-2.1 |
| Ord Int32 | Since: base-2.1 |
| Ord Int64 | Since: base-2.1 |
| Ord Integer | |
| Ord Natural | Since: base-4.8.0.0 |
| Ord Ordering | |
Defined in GHC.Classes | |
| Ord Word | |
| Ord Word8 | Since: base-2.1 |
| Ord Word16 | Since: base-2.1 |
| Ord Word32 | Since: base-2.1 |
| Ord Word64 | Since: base-2.1 |
| Ord SomeTypeRep | |
Defined in Data.Typeable.Internal Methods compare :: SomeTypeRep -> SomeTypeRep -> Ordering # (<) :: SomeTypeRep -> SomeTypeRep -> Bool # (<=) :: SomeTypeRep -> SomeTypeRep -> Bool # (>) :: SomeTypeRep -> SomeTypeRep -> Bool # (>=) :: SomeTypeRep -> SomeTypeRep -> Bool # max :: SomeTypeRep -> SomeTypeRep -> SomeTypeRep # min :: SomeTypeRep -> SomeTypeRep -> SomeTypeRep # | |
| Ord Exp | |
| Ord Match | |
| Ord Clause | |
| Ord Pat | |
| Ord Type | |
| Ord Dec | |
| Ord Name | |
| Ord FunDep | |
| Ord InjectivityAnn | |
Defined in Language.Haskell.TH.Syntax Methods compare :: InjectivityAnn -> InjectivityAnn -> Ordering # (<) :: InjectivityAnn -> InjectivityAnn -> Bool # (<=) :: InjectivityAnn -> InjectivityAnn -> Bool # (>) :: InjectivityAnn -> InjectivityAnn -> Bool # (>=) :: InjectivityAnn -> InjectivityAnn -> Bool # max :: InjectivityAnn -> InjectivityAnn -> InjectivityAnn # min :: InjectivityAnn -> InjectivityAnn -> InjectivityAnn # | |
| Ord Overlap | |
Defined in Language.Haskell.TH.Syntax | |
| Ord () | |
| Ord TyCon | |
| Ord BigNat | |
| Ord Void | Since: base-4.8.0.0 |
| Ord Unique | |
| Ord Version | Since: base-2.1 |
| Ord ThreadId | Since: base-4.2.0.0 |
Defined in GHC.Conc.Sync | |
| Ord BlockReason | Since: base-4.3.0.0 |
Defined in GHC.Conc.Sync Methods compare :: BlockReason -> BlockReason -> Ordering # (<) :: BlockReason -> BlockReason -> Bool # (<=) :: BlockReason -> BlockReason -> Bool # (>) :: BlockReason -> BlockReason -> Bool # (>=) :: BlockReason -> BlockReason -> Bool # max :: BlockReason -> BlockReason -> BlockReason # min :: BlockReason -> BlockReason -> BlockReason # | |
| Ord ThreadStatus | Since: base-4.3.0.0 |
Defined in GHC.Conc.Sync Methods compare :: ThreadStatus -> ThreadStatus -> Ordering # (<) :: ThreadStatus -> ThreadStatus -> Bool # (<=) :: ThreadStatus -> ThreadStatus -> Bool # (>) :: ThreadStatus -> ThreadStatus -> Bool # (>=) :: ThreadStatus -> ThreadStatus -> Bool # max :: ThreadStatus -> ThreadStatus -> ThreadStatus # min :: ThreadStatus -> ThreadStatus -> ThreadStatus # | |
| Ord AsyncException | Since: base-4.2.0.0 |
Defined in GHC.IO.Exception Methods compare :: AsyncException -> AsyncException -> Ordering # (<) :: AsyncException -> AsyncException -> Bool # (<=) :: AsyncException -> AsyncException -> Bool # (>) :: AsyncException -> AsyncException -> Bool # (>=) :: AsyncException -> AsyncException -> Bool # max :: AsyncException -> AsyncException -> AsyncException # min :: AsyncException -> AsyncException -> AsyncException # | |
| Ord ArrayException | Since: base-4.2.0.0 |
Defined in GHC.IO.Exception Methods compare :: ArrayException -> ArrayException -> Ordering # (<) :: ArrayException -> ArrayException -> Bool # (<=) :: ArrayException -> ArrayException -> Bool # (>) :: ArrayException -> ArrayException -> Bool # (>=) :: ArrayException -> ArrayException -> Bool # max :: ArrayException -> ArrayException -> ArrayException # min :: ArrayException -> ArrayException -> ArrayException # | |
| Ord ExitCode | |
Defined in GHC.IO.Exception | |
| Ord BufferMode | Since: base-4.2.0.0 |
Defined in GHC.IO.Handle.Types Methods compare :: BufferMode -> BufferMode -> Ordering # (<) :: BufferMode -> BufferMode -> Bool # (<=) :: BufferMode -> BufferMode -> Bool # (>) :: BufferMode -> BufferMode -> Bool # (>=) :: BufferMode -> BufferMode -> Bool # max :: BufferMode -> BufferMode -> BufferMode # min :: BufferMode -> BufferMode -> BufferMode # | |
| Ord Newline | Since: base-4.3.0.0 |
| Ord NewlineMode | Since: base-4.3.0.0 |
Defined in GHC.IO.Handle.Types Methods compare :: NewlineMode -> NewlineMode -> Ordering # (<) :: NewlineMode -> NewlineMode -> Bool # (<=) :: NewlineMode -> NewlineMode -> Bool # (>) :: NewlineMode -> NewlineMode -> Bool # (>=) :: NewlineMode -> NewlineMode -> Bool # max :: NewlineMode -> NewlineMode -> NewlineMode # min :: NewlineMode -> NewlineMode -> NewlineMode # | |
| Ord ErrorCall | Since: base-4.7.0.0 |
| Ord ArithException | Since: base-3.0 |
Defined in GHC.Exception.Type Methods compare :: ArithException -> ArithException -> Ordering # (<) :: ArithException -> ArithException -> Bool # (<=) :: ArithException -> ArithException -> Bool # (>) :: ArithException -> ArithException -> Bool # (>=) :: ArithException -> ArithException -> Bool # max :: ArithException -> ArithException -> ArithException # min :: ArithException -> ArithException -> ArithException # | |
| Ord All | Since: base-2.1 |
| Ord Any | Since: base-2.1 |
| Ord Fixity | Since: base-4.6.0.0 |
| Ord Associativity | Since: base-4.6.0.0 |
Defined in GHC.Generics Methods compare :: Associativity -> Associativity -> Ordering # (<) :: Associativity -> Associativity -> Bool # (<=) :: Associativity -> Associativity -> Bool # (>) :: Associativity -> Associativity -> Bool # (>=) :: Associativity -> Associativity -> Bool # max :: Associativity -> Associativity -> Associativity # min :: Associativity -> Associativity -> Associativity # | |
| Ord SourceUnpackedness | Since: base-4.9.0.0 |
Defined in GHC.Generics Methods compare :: SourceUnpackedness -> SourceUnpackedness -> Ordering # (<) :: SourceUnpackedness -> SourceUnpackedness -> Bool # (<=) :: SourceUnpackedness -> SourceUnpackedness -> Bool # (>) :: SourceUnpackedness -> SourceUnpackedness -> Bool # (>=) :: SourceUnpackedness -> SourceUnpackedness -> Bool # max :: SourceUnpackedness -> SourceUnpackedness -> SourceUnpackedness # min :: SourceUnpackedness -> SourceUnpackedness -> SourceUnpackedness # | |
| Ord SourceStrictness | Since: base-4.9.0.0 |
Defined in GHC.Generics Methods compare :: SourceStrictness -> SourceStrictness -> Ordering # (<) :: SourceStrictness -> SourceStrictness -> Bool # (<=) :: SourceStrictness -> SourceStrictness -> Bool # (>) :: SourceStrictness -> SourceStrictness -> Bool # (>=) :: SourceStrictness -> SourceStrictness -> Bool # max :: SourceStrictness -> SourceStrictness -> SourceStrictness # min :: SourceStrictness -> SourceStrictness -> SourceStrictness # | |
| Ord DecidedStrictness | Since: base-4.9.0.0 |
Defined in GHC.Generics Methods compare :: DecidedStrictness -> DecidedStrictness -> Ordering # (<) :: DecidedStrictness -> DecidedStrictness -> Bool # (<=) :: DecidedStrictness -> DecidedStrictness -> Bool # (>) :: DecidedStrictness -> DecidedStrictness -> Bool # (>=) :: DecidedStrictness -> DecidedStrictness -> Bool # max :: DecidedStrictness -> DecidedStrictness -> DecidedStrictness # min :: DecidedStrictness -> DecidedStrictness -> DecidedStrictness # | |
| Ord SomeSymbol | Since: base-4.7.0.0 |
Defined in GHC.TypeLits Methods compare :: SomeSymbol -> SomeSymbol -> Ordering # (<) :: SomeSymbol -> SomeSymbol -> Bool # (<=) :: SomeSymbol -> SomeSymbol -> Bool # (>) :: SomeSymbol -> SomeSymbol -> Bool # (>=) :: SomeSymbol -> SomeSymbol -> Bool # max :: SomeSymbol -> SomeSymbol -> SomeSymbol # min :: SomeSymbol -> SomeSymbol -> SomeSymbol # | |
| Ord SomeNat | Since: base-4.7.0.0 |
| Ord CChar | |
| Ord CSChar | |
| Ord CUChar | |
| Ord CShort | |
| Ord CUShort | |
| Ord CInt | |
| Ord CUInt | |
| Ord CLong | |
| Ord CULong | |
| Ord CLLong | |
| Ord CULLong | |
| Ord CBool | |
| Ord CFloat | |
| Ord CDouble | |
| Ord CPtrdiff | |
Defined in Foreign.C.Types | |
| Ord CSize | |
| Ord CWchar | |
| Ord CSigAtomic | |
Defined in Foreign.C.Types Methods compare :: CSigAtomic -> CSigAtomic -> Ordering # (<) :: CSigAtomic -> CSigAtomic -> Bool # (<=) :: CSigAtomic -> CSigAtomic -> Bool # (>) :: CSigAtomic -> CSigAtomic -> Bool # (>=) :: CSigAtomic -> CSigAtomic -> Bool # max :: CSigAtomic -> CSigAtomic -> CSigAtomic # min :: CSigAtomic -> CSigAtomic -> CSigAtomic # | |
| Ord CClock | |
| Ord CTime | |
| Ord CUSeconds | |
| Ord CSUSeconds | |
Defined in Foreign.C.Types Methods compare :: CSUSeconds -> CSUSeconds -> Ordering # (<) :: CSUSeconds -> CSUSeconds -> Bool # (<=) :: CSUSeconds -> CSUSeconds -> Bool # (>) :: CSUSeconds -> CSUSeconds -> Bool # (>=) :: CSUSeconds -> CSUSeconds -> Bool # max :: CSUSeconds -> CSUSeconds -> CSUSeconds # min :: CSUSeconds -> CSUSeconds -> CSUSeconds # | |
| Ord CIntPtr | |
| Ord CUIntPtr | |
Defined in Foreign.C.Types | |
| Ord CIntMax | |
| Ord CUIntMax | |
Defined in Foreign.C.Types | |
| Ord WordPtr | |
| Ord IntPtr | |
| Ord IOMode | Since: base-4.2.0.0 |
| Ord Fingerprint | Since: base-4.4.0.0 |
Defined in GHC.Fingerprint.Type Methods compare :: Fingerprint -> Fingerprint -> Ordering # (<) :: Fingerprint -> Fingerprint -> Bool # (<=) :: Fingerprint -> Fingerprint -> Bool # (>) :: Fingerprint -> Fingerprint -> Bool # (>=) :: Fingerprint -> Fingerprint -> Bool # max :: Fingerprint -> Fingerprint -> Fingerprint # min :: Fingerprint -> Fingerprint -> Fingerprint # | |
| Ord ShortByteString | |
Defined in Data.ByteString.Short.Internal Methods compare :: ShortByteString -> ShortByteString -> Ordering # (<) :: ShortByteString -> ShortByteString -> Bool # (<=) :: ShortByteString -> ShortByteString -> Bool # (>) :: ShortByteString -> ShortByteString -> Bool # (>=) :: ShortByteString -> ShortByteString -> Bool # max :: ShortByteString -> ShortByteString -> ShortByteString # min :: ShortByteString -> ShortByteString -> ShortByteString # | |
| Ord ByteString | |
Defined in Data.ByteString.Lazy.Internal Methods compare :: ByteString -> ByteString -> Ordering # (<) :: ByteString -> ByteString -> Bool # (<=) :: ByteString -> ByteString -> Bool # (>) :: ByteString -> ByteString -> Bool # (>=) :: ByteString -> ByteString -> Bool # max :: ByteString -> ByteString -> ByteString # min :: ByteString -> ByteString -> ByteString # | |
| Ord ByteString | |
Defined in Data.ByteString.Internal Methods compare :: ByteString -> ByteString -> Ordering # (<) :: ByteString -> ByteString -> Bool # (<=) :: ByteString -> ByteString -> Bool # (>) :: ByteString -> ByteString -> Bool # (>=) :: ByteString -> ByteString -> Bool # max :: ByteString -> ByteString -> ByteString # min :: ByteString -> ByteString -> ByteString # | |
| Ord IntSet | |
| Ord ModName | |
Defined in Language.Haskell.TH.Syntax | |
| Ord PkgName | |
Defined in Language.Haskell.TH.Syntax | |
| Ord Module | |
| Ord OccName | |
Defined in Language.Haskell.TH.Syntax | |
| Ord NameFlavour | |
Defined in Language.Haskell.TH.Syntax Methods compare :: NameFlavour -> NameFlavour -> Ordering # (<) :: NameFlavour -> NameFlavour -> Bool # (<=) :: NameFlavour -> NameFlavour -> Bool # (>) :: NameFlavour -> NameFlavour -> Bool # (>=) :: NameFlavour -> NameFlavour -> Bool # max :: NameFlavour -> NameFlavour -> NameFlavour # min :: NameFlavour -> NameFlavour -> NameFlavour # | |
| Ord NameSpace | |
| Ord Loc | |
| Ord Info | |
| Ord ModuleInfo | |
Defined in Language.Haskell.TH.Syntax Methods compare :: ModuleInfo -> ModuleInfo -> Ordering # (<) :: ModuleInfo -> ModuleInfo -> Bool # (<=) :: ModuleInfo -> ModuleInfo -> Bool # (>) :: ModuleInfo -> ModuleInfo -> Bool # (>=) :: ModuleInfo -> ModuleInfo -> Bool # max :: ModuleInfo -> ModuleInfo -> ModuleInfo # min :: ModuleInfo -> ModuleInfo -> ModuleInfo # | |
| Ord Fixity | |
| Ord FixityDirection | |
Defined in Language.Haskell.TH.Syntax Methods compare :: FixityDirection -> FixityDirection -> Ordering # (<) :: FixityDirection -> FixityDirection -> Bool # (<=) :: FixityDirection -> FixityDirection -> Bool # (>) :: FixityDirection -> FixityDirection -> Bool # (>=) :: FixityDirection -> FixityDirection -> Bool # max :: FixityDirection -> FixityDirection -> FixityDirection # min :: FixityDirection -> FixityDirection -> FixityDirection # | |
| Ord Lit | |
| Ord Body | |
| Ord Guard | |
| Ord Stmt | |
| Ord Range | |
| Ord DerivClause | |
Defined in Language.Haskell.TH.Syntax Methods compare :: DerivClause -> DerivClause -> Ordering # (<) :: DerivClause -> DerivClause -> Bool # (<=) :: DerivClause -> DerivClause -> Bool # (>) :: DerivClause -> DerivClause -> Bool # (>=) :: DerivClause -> DerivClause -> Bool # max :: DerivClause -> DerivClause -> DerivClause # min :: DerivClause -> DerivClause -> DerivClause # | |
| Ord DerivStrategy | |
Defined in Language.Haskell.TH.Syntax Methods compare :: DerivStrategy -> DerivStrategy -> Ordering # (<) :: DerivStrategy -> DerivStrategy -> Bool # (<=) :: DerivStrategy -> DerivStrategy -> Bool # (>) :: DerivStrategy -> DerivStrategy -> Bool # (>=) :: DerivStrategy -> DerivStrategy -> Bool # max :: DerivStrategy -> DerivStrategy -> DerivStrategy # min :: DerivStrategy -> DerivStrategy -> DerivStrategy # | |
| Ord TypeFamilyHead | |
Defined in Language.Haskell.TH.Syntax Methods compare :: TypeFamilyHead -> TypeFamilyHead -> Ordering # (<) :: TypeFamilyHead -> TypeFamilyHead -> Bool # (<=) :: TypeFamilyHead -> TypeFamilyHead -> Bool # (>) :: TypeFamilyHead -> TypeFamilyHead -> Bool # (>=) :: TypeFamilyHead -> TypeFamilyHead -> Bool # max :: TypeFamilyHead -> TypeFamilyHead -> TypeFamilyHead # min :: TypeFamilyHead -> TypeFamilyHead -> TypeFamilyHead # | |
| Ord TySynEqn | |
Defined in Language.Haskell.TH.Syntax | |
| Ord Foreign | |
Defined in Language.Haskell.TH.Syntax | |
| Ord Callconv | |
Defined in Language.Haskell.TH.Syntax | |
| Ord Safety | |
| Ord Pragma | |
| Ord Inline | |
| Ord RuleMatch | |
| Ord Phases | |
| Ord RuleBndr | |
Defined in Language.Haskell.TH.Syntax | |
| Ord AnnTarget | |
| Ord SourceUnpackedness | |
Defined in Language.Haskell.TH.Syntax Methods compare :: SourceUnpackedness -> SourceUnpackedness -> Ordering # (<) :: SourceUnpackedness -> SourceUnpackedness -> Bool # (<=) :: SourceUnpackedness -> SourceUnpackedness -> Bool # (>) :: SourceUnpackedness -> SourceUnpackedness -> Bool # (>=) :: SourceUnpackedness -> SourceUnpackedness -> Bool # max :: SourceUnpackedness -> SourceUnpackedness -> SourceUnpackedness # min :: SourceUnpackedness -> SourceUnpackedness -> SourceUnpackedness # | |
| Ord SourceStrictness | |
Defined in Language.Haskell.TH.Syntax Methods compare :: SourceStrictness -> SourceStrictness -> Ordering # (<) :: SourceStrictness -> SourceStrictness -> Bool # (<=) :: SourceStrictness -> SourceStrictness -> Bool # (>) :: SourceStrictness -> SourceStrictness -> Bool # (>=) :: SourceStrictness -> SourceStrictness -> Bool # max :: SourceStrictness -> SourceStrictness -> SourceStrictness # min :: SourceStrictness -> SourceStrictness -> SourceStrictness # | |
| Ord DecidedStrictness | |
Defined in Language.Haskell.TH.Syntax Methods compare :: DecidedStrictness -> DecidedStrictness -> Ordering # (<) :: DecidedStrictness -> DecidedStrictness -> Bool # (<=) :: DecidedStrictness -> DecidedStrictness -> Bool # (>) :: DecidedStrictness -> DecidedStrictness -> Bool # (>=) :: DecidedStrictness -> DecidedStrictness -> Bool # max :: DecidedStrictness -> DecidedStrictness -> DecidedStrictness # min :: DecidedStrictness -> DecidedStrictness -> DecidedStrictness # | |
| Ord Con | |
| Ord Bang | |
| Ord PatSynDir | |
| Ord PatSynArgs | |
Defined in Language.Haskell.TH.Syntax Methods compare :: PatSynArgs -> PatSynArgs -> Ordering # (<) :: PatSynArgs -> PatSynArgs -> Bool # (<=) :: PatSynArgs -> PatSynArgs -> Bool # (>) :: PatSynArgs -> PatSynArgs -> Bool # (>=) :: PatSynArgs -> PatSynArgs -> Bool # max :: PatSynArgs -> PatSynArgs -> PatSynArgs # min :: PatSynArgs -> PatSynArgs -> PatSynArgs # | |
| Ord TyVarBndr | |
| Ord FamilyResultSig | |
Defined in Language.Haskell.TH.Syntax Methods compare :: FamilyResultSig -> FamilyResultSig -> Ordering # (<) :: FamilyResultSig -> FamilyResultSig -> Bool # (<=) :: FamilyResultSig -> FamilyResultSig -> Bool # (>) :: FamilyResultSig -> FamilyResultSig -> Bool # (>=) :: FamilyResultSig -> FamilyResultSig -> Bool # max :: FamilyResultSig -> FamilyResultSig -> FamilyResultSig # min :: FamilyResultSig -> FamilyResultSig -> FamilyResultSig # | |
| Ord TyLit | |
| Ord Role | |
| Ord AnnLookup | |
| Ord Undefined Source # | |
| Ord a => Ord [a] | |
| Ord a => Ord (Maybe a) | Since: base-2.1 |
| Integral a => Ord (Ratio a) | Since: base-2.0.1 |
| Ord (Ptr a) | Since: base-2.1 |
| Ord (FunPtr a) | |
Defined in GHC.Ptr | |
| Ord p => Ord (Par1 p) | Since: base-4.7.0.0 |
| Ord (Fixed a) | Since: base-2.1 |
| Ord a => Ord (Min a) | Since: base-4.9.0.0 |
| Ord a => Ord (Max a) | Since: base-4.9.0.0 |
| Ord a => Ord (First a) | Since: base-4.9.0.0 |
| Ord a => Ord (Last a) | Since: base-4.9.0.0 |
| Ord m => Ord (WrappedMonoid m) | Since: base-4.9.0.0 |
Defined in Data.Semigroup Methods compare :: WrappedMonoid m -> WrappedMonoid m -> Ordering # (<) :: WrappedMonoid m -> WrappedMonoid m -> Bool # (<=) :: WrappedMonoid m -> WrappedMonoid m -> Bool # (>) :: WrappedMonoid m -> WrappedMonoid m -> Bool # (>=) :: WrappedMonoid m -> WrappedMonoid m -> Bool # max :: WrappedMonoid m -> WrappedMonoid m -> WrappedMonoid m # min :: WrappedMonoid m -> WrappedMonoid m -> WrappedMonoid m # | |
| Ord a => Ord (Option a) | Since: base-4.9.0.0 |
Defined in Data.Semigroup | |
| Ord a => Ord (ZipList a) | Since: base-4.7.0.0 |
| Ord a => Ord (Identity a) | Since: base-4.8.0.0 |
Defined in Data.Functor.Identity | |
| Ord a => Ord (First a) | Since: base-2.1 |
| Ord a => Ord (Last a) | Since: base-2.1 |
| Ord a => Ord (Dual a) | Since: base-2.1 |
| Ord a => Ord (Sum a) | Since: base-2.1 |
| Ord a => Ord (Product a) | Since: base-2.1 |
| Ord a => Ord (Down a) | Since: base-4.6.0.0 |
| Ord a => Ord (NonEmpty a) | Since: base-4.9.0.0 |
| Ord a => Ord (IntMap a) | |
Defined in Data.IntMap.Internal | |
| Ord a => Ord (Seq a) | |
| Ord a => Ord (ViewL a) | |
Defined in Data.Sequence.Internal | |
| Ord a => Ord (ViewR a) | |
Defined in Data.Sequence.Internal | |
| Ord a => Ord (Set a) | |
| Ord a => Ord (Hashed a) | |
Defined in Data.Hashable.Class | |
| Ord a => Ord (HashSet a) | |
| (Ord a, Ord b) => Ord (Either a b) | Since: base-2.1 |
| Ord (V1 p) | Since: base-4.9.0.0 |
| Ord (U1 p) | Since: base-4.7.0.0 |
| Ord (TypeRep a) | Since: base-4.4.0.0 |
| (Ord a, Ord b) => Ord (a, b) | |
| (Ix i, Ord e) => Ord (Array i e) | Since: base-2.1 |
| Ord a => Ord (Arg a b) | Since: base-4.9.0.0 |
| Ord (Proxy s) | Since: base-4.7.0.0 |
| (Ord k, Ord v) => Ord (Map k v) | |
| (Ord k, Ord v) => Ord (HashMap k v) | The order is total. Note: Because the hash is not guaranteed to be stable across library
versions, OSes, or architectures, neither is an actual order of elements in
|
Defined in Data.HashMap.Base | |
| (Ord1 m, Ord a) => Ord (MaybeT m a) | |
Defined in Control.Monad.Trans.Maybe | |
| (Ord e, Ord a) => Ord (Validation e a) Source # | |
Defined in Relude.Extra.Validation Methods compare :: Validation e a -> Validation e a -> Ordering # (<) :: Validation e a -> Validation e a -> Bool # (<=) :: Validation e a -> Validation e a -> Bool # (>) :: Validation e a -> Validation e a -> Bool # (>=) :: Validation e a -> Validation e a -> Bool # max :: Validation e a -> Validation e a -> Validation e a # min :: Validation e a -> Validation e a -> Validation e a # | |
| Ord (f p) => Ord (Rec1 f p) | Since: base-4.7.0.0 |
Defined in GHC.Generics | |
| Ord (URec (Ptr ()) p) | Since: base-4.9.0.0 |
Defined in GHC.Generics Methods compare :: URec (Ptr ()) p -> URec (Ptr ()) p -> Ordering # (<) :: URec (Ptr ()) p -> URec (Ptr ()) p -> Bool # (<=) :: URec (Ptr ()) p -> URec (Ptr ()) p -> Bool # (>) :: URec (Ptr ()) p -> URec (Ptr ()) p -> Bool # (>=) :: URec (Ptr ()) p -> URec (Ptr ()) p -> Bool # max :: URec (Ptr ()) p -> URec (Ptr ()) p -> URec (Ptr ()) p # min :: URec (Ptr ()) p -> URec (Ptr ()) p -> URec (Ptr ()) p # | |
| Ord (URec Char p) | Since: base-4.9.0.0 |
Defined in GHC.Generics | |
| Ord (URec Double p) | Since: base-4.9.0.0 |
Defined in GHC.Generics Methods compare :: URec Double p -> URec Double p -> Ordering # (<) :: URec Double p -> URec Double p -> Bool # (<=) :: URec Double p -> URec Double p -> Bool # (>) :: URec Double p -> URec Double p -> Bool # (>=) :: URec Double p -> URec Double p -> Bool # | |
| Ord (URec Float p) | |
Defined in GHC.Generics | |
| Ord (URec Int p) | Since: base-4.9.0.0 |
| Ord (URec Word p) | Since: base-4.9.0.0 |
Defined in GHC.Generics | |
| (Ord a, Ord b, Ord c) => Ord (a, b, c) | |
| Ord a => Ord (Const a b) | Since: base-4.9.0.0 |
| Ord (f a) => Ord (Ap f a) | Since: base-4.12.0.0 |
| Ord (f a) => Ord (Alt f a) | Since: base-4.8.0.0 |
Defined in Data.Semigroup.Internal | |
| Ord (a :~: b) | Since: base-4.7.0.0 |
Defined in Data.Type.Equality | |
| (Ord1 f, Ord a) => Ord (IdentityT f a) | |
Defined in Control.Monad.Trans.Identity Methods compare :: IdentityT f a -> IdentityT f a -> Ordering # (<) :: IdentityT f a -> IdentityT f a -> Bool # (<=) :: IdentityT f a -> IdentityT f a -> Bool # (>) :: IdentityT f a -> IdentityT f a -> Bool # (>=) :: IdentityT f a -> IdentityT f a -> Bool # | |
| (Ord e, Ord1 m, Ord a) => Ord (ErrorT e m a) | |
Defined in Control.Monad.Trans.Error | |
| (Ord e, Ord1 m, Ord a) => Ord (ExceptT e m a) | |
Defined in Control.Monad.Trans.Except Methods compare :: ExceptT e m a -> ExceptT e m a -> Ordering # (<) :: ExceptT e m a -> ExceptT e m a -> Bool # (<=) :: ExceptT e m a -> ExceptT e m a -> Bool # (>) :: ExceptT e m a -> ExceptT e m a -> Bool # (>=) :: ExceptT e m a -> ExceptT e m a -> Bool # | |
| Ord c => Ord (K1 i c p) | Since: base-4.7.0.0 |
Defined in GHC.Generics | |
| (Ord (f p), Ord (g p)) => Ord ((f :+: g) p) | Since: base-4.7.0.0 |
Defined in GHC.Generics | |
| (Ord (f p), Ord (g p)) => Ord ((f :*: g) p) | Since: base-4.7.0.0 |
Defined in GHC.Generics | |
| (Ord a, Ord b, Ord c, Ord d) => Ord (a, b, c, d) | |
Defined in GHC.Classes | |
| (Ord1 f, Ord1 g, Ord a) => Ord (Product f g a) | Since: base-4.9.0.0 |
Defined in Data.Functor.Product Methods compare :: Product f g a -> Product f g a -> Ordering # (<) :: Product f g a -> Product f g a -> Bool # (<=) :: Product f g a -> Product f g a -> Bool # (>) :: Product f g a -> Product f g a -> Bool # (>=) :: Product f g a -> Product f g a -> Bool # | |
| (Ord1 f, Ord1 g, Ord a) => Ord (Sum f g a) | Since: base-4.9.0.0 |
| Ord (a :~~: b) | Since: base-4.10.0.0 |
| Ord (f p) => Ord (M1 i c f p) | Since: base-4.7.0.0 |
| Ord (f (g p)) => Ord ((f :.: g) p) | Since: base-4.7.0.0 |
Defined in GHC.Generics | |
| (Ord a, Ord b, Ord c, Ord d, Ord e) => Ord (a, b, c, d, e) | |
Defined in GHC.Classes Methods compare :: (a, b, c, d, e) -> (a, b, c, d, e) -> Ordering # (<) :: (a, b, c, d, e) -> (a, b, c, d, e) -> Bool # (<=) :: (a, b, c, d, e) -> (a, b, c, d, e) -> Bool # (>) :: (a, b, c, d, e) -> (a, b, c, d, e) -> Bool # (>=) :: (a, b, c, d, e) -> (a, b, c, d, e) -> Bool # max :: (a, b, c, d, e) -> (a, b, c, d, e) -> (a, b, c, d, e) # min :: (a, b, c, d, e) -> (a, b, c, d, e) -> (a, b, c, d, e) # | |
| (Ord1 f, Ord1 g, Ord a) => Ord (Compose f g a) | Since: base-4.9.0.0 |
Defined in Data.Functor.Compose Methods compare :: Compose f g a -> Compose f g a -> Ordering # (<) :: Compose f g a -> Compose f g a -> Bool # (<=) :: Compose f g a -> Compose f g a -> Bool # (>) :: Compose f g a -> Compose f g a -> Bool # (>=) :: Compose f g a -> Compose f g a -> Bool # | |
| (Ord a, Ord b, Ord c, Ord d, Ord e, Ord f) => Ord (a, b, c, d, e, f) | |
Defined in GHC.Classes Methods compare :: (a, b, c, d, e, f) -> (a, b, c, d, e, f) -> Ordering # (<) :: (a, b, c, d, e, f) -> (a, b, c, d, e, f) -> Bool # (<=) :: (a, b, c, d, e, f) -> (a, b, c, d, e, f) -> Bool # (>) :: (a, b, c, d, e, f) -> (a, b, c, d, e, f) -> Bool # (>=) :: (a, b, c, d, e, f) -> (a, b, c, d, e, f) -> Bool # max :: (a, b, c, d, e, f) -> (a, b, c, d, e, f) -> (a, b, c, d, e, f) # min :: (a, b, c, d, e, f) -> (a, b, c, d, e, f) -> (a, b, c, d, e, f) # | |
| (Ord a, Ord b, Ord c, Ord d, Ord e, Ord f, Ord g) => Ord (a, b, c, d, e, f, g) | |
Defined in GHC.Classes Methods compare :: (a, b, c, d, e, f, g) -> (a, b, c, d, e, f, g) -> Ordering # (<) :: (a, b, c, d, e, f, g) -> (a, b, c, d, e, f, g) -> Bool # (<=) :: (a, b, c, d, e, f, g) -> (a, b, c, d, e, f, g) -> Bool # (>) :: (a, b, c, d, e, f, g) -> (a, b, c, d, e, f, g) -> Bool # (>=) :: (a, b, c, d, e, f, g) -> (a, b, c, d, e, f, g) -> Bool # max :: (a, b, c, d, e, f, g) -> (a, b, c, d, e, f, g) -> (a, b, c, d, e, f, g) # min :: (a, b, c, d, e, f, g) -> (a, b, c, d, e, f, g) -> (a, b, c, d, e, f, g) # | |
| (Ord a, Ord b, Ord c, Ord d, Ord e, Ord f, Ord g, Ord h) => Ord (a, b, c, d, e, f, g, h) | |
Defined in GHC.Classes Methods compare :: (a, b, c, d, e, f, g, h) -> (a, b, c, d, e, f, g, h) -> Ordering # (<) :: (a, b, c, d, e, f, g, h) -> (a, b, c, d, e, f, g, h) -> Bool # (<=) :: (a, b, c, d, e, f, g, h) -> (a, b, c, d, e, f, g, h) -> Bool # (>) :: (a, b, c, d, e, f, g, h) -> (a, b, c, d, e, f, g, h) -> Bool # (>=) :: (a, b, c, d, e, f, g, h) -> (a, b, c, d, e, f, g, h) -> Bool # max :: (a, b, c, d, e, f, g, h) -> (a, b, c, d, e, f, g, h) -> (a, b, c, d, e, f, g, h) # min :: (a, b, c, d, e, f, g, h) -> (a, b, c, d, e, f, g, h) -> (a, b, c, d, e, f, g, h) # | |
| (Ord a, Ord b, Ord c, Ord d, Ord e, Ord f, Ord g, Ord h, Ord i) => Ord (a, b, c, d, e, f, g, h, i) | |
Defined in GHC.Classes Methods compare :: (a, b, c, d, e, f, g, h, i) -> (a, b, c, d, e, f, g, h, i) -> Ordering # (<) :: (a, b, c, d, e, f, g, h, i) -> (a, b, c, d, e, f, g, h, i) -> Bool # (<=) :: (a, b, c, d, e, f, g, h, i) -> (a, b, c, d, e, f, g, h, i) -> Bool # (>) :: (a, b, c, d, e, f, g, h, i) -> (a, b, c, d, e, f, g, h, i) -> Bool # (>=) :: (a, b, c, d, e, f, g, h, i) -> (a, b, c, d, e, f, g, h, i) -> Bool # max :: (a, b, c, d, e, f, g, h, i) -> (a, b, c, d, e, f, g, h, i) -> (a, b, c, d, e, f, g, h, i) # min :: (a, b, c, d, e, f, g, h, i) -> (a, b, c, d, e, f, g, h, i) -> (a, b, c, d, e, f, g, h, i) # | |
| (Ord a, Ord b, Ord c, Ord d, Ord e, Ord f, Ord g, Ord h, Ord i, Ord j) => Ord (a, b, c, d, e, f, g, h, i, j) | |
Defined in GHC.Classes Methods compare :: (a, b, c, d, e, f, g, h, i, j) -> (a, b, c, d, e, f, g, h, i, j) -> Ordering # (<) :: (a, b, c, d, e, f, g, h, i, j) -> (a, b, c, d, e, f, g, h, i, j) -> Bool # (<=) :: (a, b, c, d, e, f, g, h, i, j) -> (a, b, c, d, e, f, g, h, i, j) -> Bool # (>) :: (a, b, c, d, e, f, g, h, i, j) -> (a, b, c, d, e, f, g, h, i, j) -> Bool # (>=) :: (a, b, c, d, e, f, g, h, i, j) -> (a, b, c, d, e, f, g, h, i, j) -> Bool # max :: (a, b, c, d, e, f, g, h, i, j) -> (a, b, c, d, e, f, g, h, i, j) -> (a, b, c, d, e, f, g, h, i, j) # min :: (a, b, c, d, e, f, g, h, i, j) -> (a, b, c, d, e, f, g, h, i, j) -> (a, b, c, d, e, f, g, h, i, j) # | |
| (Ord a, Ord b, Ord c, Ord d, Ord e, Ord f, Ord g, Ord h, Ord i, Ord j, Ord k) => Ord (a, b, c, d, e, f, g, h, i, j, k) | |
Defined in GHC.Classes Methods compare :: (a, b, c, d, e, f, g, h, i, j, k) -> (a, b, c, d, e, f, g, h, i, j, k) -> Ordering # (<) :: (a, b, c, d, e, f, g, h, i, j, k) -> (a, b, c, d, e, f, g, h, i, j, k) -> Bool # (<=) :: (a, b, c, d, e, f, g, h, i, j, k) -> (a, b, c, d, e, f, g, h, i, j, k) -> Bool # (>) :: (a, b, c, d, e, f, g, h, i, j, k) -> (a, b, c, d, e, f, g, h, i, j, k) -> Bool # (>=) :: (a, b, c, d, e, f, g, h, i, j, k) -> (a, b, c, d, e, f, g, h, i, j, k) -> Bool # max :: (a, b, c, d, e, f, g, h, i, j, k) -> (a, b, c, d, e, f, g, h, i, j, k) -> (a, b, c, d, e, f, g, h, i, j, k) # min :: (a, b, c, d, e, f, g, h, i, j, k) -> (a, b, c, d, e, f, g, h, i, j, k) -> (a, b, c, d, e, f, g, h, i, j, k) # | |
| (Ord a, Ord b, Ord c, Ord d, Ord e, Ord f, Ord g, Ord h, Ord i, Ord j, Ord k, Ord l) => Ord (a, b, c, d, e, f, g, h, i, j, k, l) | |
Defined in GHC.Classes Methods compare :: (a, b, c, d, e, f, g, h, i, j, k, l) -> (a, b, c, d, e, f, g, h, i, j, k, l) -> Ordering # (<) :: (a, b, c, d, e, f, g, h, i, j, k, l) -> (a, b, c, d, e, f, g, h, i, j, k, l) -> Bool # (<=) :: (a, b, c, d, e, f, g, h, i, j, k, l) -> (a, b, c, d, e, f, g, h, i, j, k, l) -> Bool # (>) :: (a, b, c, d, e, f, g, h, i, j, k, l) -> (a, b, c, d, e, f, g, h, i, j, k, l) -> Bool # (>=) :: (a, b, c, d, e, f, g, h, i, j, k, l) -> (a, b, c, d, e, f, g, h, i, j, k, l) -> Bool # max :: (a, b, c, d, e, f, g, h, i, j, k, l) -> (a, b, c, d, e, f, g, h, i, j, k, l) -> (a, b, c, d, e, f, g, h, i, j, k, l) # min :: (a, b, c, d, e, f, g, h, i, j, k, l) -> (a, b, c, d, e, f, g, h, i, j, k, l) -> (a, b, c, d, e, f, g, h, i, j, k, l) # | |
| (Ord a, Ord b, Ord c, Ord d, Ord e, Ord f, Ord g, Ord h, Ord i, Ord j, Ord k, Ord l, Ord m) => Ord (a, b, c, d, e, f, g, h, i, j, k, l, m) | |
Defined in GHC.Classes Methods compare :: (a, b, c, d, e, f, g, h, i, j, k, l, m) -> (a, b, c, d, e, f, g, h, i, j, k, l, m) -> Ordering # (<) :: (a, b, c, d, e, f, g, h, i, j, k, l, m) -> (a, b, c, d, e, f, g, h, i, j, k, l, m) -> Bool # (<=) :: (a, b, c, d, e, f, g, h, i, j, k, l, m) -> (a, b, c, d, e, f, g, h, i, j, k, l, m) -> Bool # (>) :: (a, b, c, d, e, f, g, h, i, j, k, l, m) -> (a, b, c, d, e, f, g, h, i, j, k, l, m) -> Bool # (>=) :: (a, b, c, d, e, f, g, h, i, j, k, l, m) -> (a, b, c, d, e, f, g, h, i, j, k, l, m) -> Bool # max :: (a, b, c, d, e, f, g, h, i, j, k, l, m) -> (a, b, c, d, e, f, g, h, i, j, k, l, m) -> (a, b, c, d, e, f, g, h, i, j, k, l, m) # min :: (a, b, c, d, e, f, g, h, i, j, k, l, m) -> (a, b, c, d, e, f, g, h, i, j, k, l, m) -> (a, b, c, d, e, f, g, h, i, j, k, l, m) # | |
| (Ord a, Ord b, Ord c, Ord d, Ord e, Ord f, Ord g, Ord h, Ord i, Ord j, Ord k, Ord l, Ord m, Ord n) => Ord (a, b, c, d, e, f, g, h, i, j, k, l, m, n) | |
Defined in GHC.Classes Methods compare :: (a, b, c, d, e, f, g, h, i, j, k, l, m, n) -> (a, b, c, d, e, f, g, h, i, j, k, l, m, n) -> Ordering # (<) :: (a, b, c, d, e, f, g, h, i, j, k, l, m, n) -> (a, b, c, d, e, f, g, h, i, j, k, l, m, n) -> Bool # (<=) :: (a, b, c, d, e, f, g, h, i, j, k, l, m, n) -> (a, b, c, d, e, f, g, h, i, j, k, l, m, n) -> Bool # (>) :: (a, b, c, d, e, f, g, h, i, j, k, l, m, n) -> (a, b, c, d, e, f, g, h, i, j, k, l, m, n) -> Bool # (>=) :: (a, b, c, d, e, f, g, h, i, j, k, l, m, n) -> (a, b, c, d, e, f, g, h, i, j, k, l, m, n) -> Bool # max :: (a, b, c, d, e, f, g, h, i, j, k, l, m, n) -> (a, b, c, d, e, f, g, h, i, j, k, l, m, n) -> (a, b, c, d, e, f, g, h, i, j, k, l, m, n) # min :: (a, b, c, d, e, f, g, h, i, j, k, l, m, n) -> (a, b, c, d, e, f, g, h, i, j, k, l, m, n) -> (a, b, c, d, e, f, g, h, i, j, k, l, m, n) # | |
| (Ord a, Ord b, Ord c, Ord d, Ord e, Ord f, Ord g, Ord h, Ord i, Ord j, Ord k, Ord l, Ord m, Ord n, Ord o) => Ord (a, b, c, d, e, f, g, h, i, j, k, l, m, n, o) | |
Defined in GHC.Classes Methods compare :: (a, b, c, d, e, f, g, h, i, j, k, l, m, n, o) -> (a, b, c, d, e, f, g, h, i, j, k, l, m, n, o) -> Ordering # (<) :: (a, b, c, d, e, f, g, h, i, j, k, l, m, n, o) -> (a, b, c, d, e, f, g, h, i, j, k, l, m, n, o) -> Bool # (<=) :: (a, b, c, d, e, f, g, h, i, j, k, l, m, n, o) -> (a, b, c, d, e, f, g, h, i, j, k, l, m, n, o) -> Bool # (>) :: (a, b, c, d, e, f, g, h, i, j, k, l, m, n, o) -> (a, b, c, d, e, f, g, h, i, j, k, l, m, n, o) -> Bool # (>=) :: (a, b, c, d, e, f, g, h, i, j, k, l, m, n, o) -> (a, b, c, d, e, f, g, h, i, j, k, l, m, n, o) -> Bool # max :: (a, b, c, d, e, f, g, h, i, j, k, l, m, n, o) -> (a, b, c, d, e, f, g, h, i, j, k, l, m, n, o) -> (a, b, c, d, e, f, g, h, i, j, k, l, m, n, o) # min :: (a, b, c, d, e, f, g, h, i, j, k, l, m, n, o) -> (a, b, c, d, e, f, g, h, i, j, k, l, m, n, o) -> (a, b, c, d, e, f, g, h, i, j, k, l, m, n, o) # | |
Instances
| Bounded Ordering | Since: base-2.1 |
| Enum Ordering | Since: base-2.1 |
| Eq Ordering | |
| Data Ordering | Since: base-4.0.0.0 |
Defined in Data.Data Methods gfoldl :: (forall d b. Data d => c (d -> b) -> d -> c b) -> (forall g. g -> c g) -> Ordering -> c Ordering # gunfold :: (forall b r. Data b => c (b -> r) -> c r) -> (forall r. r -> c r) -> Constr -> c Ordering # toConstr :: Ordering -> Constr # dataTypeOf :: Ordering -> DataType # dataCast1 :: Typeable t => (forall d. Data d => c (t d)) -> Maybe (c Ordering) # dataCast2 :: Typeable t => (forall d e. (Data d, Data e) => c (t d e)) -> Maybe (c Ordering) # gmapT :: (forall b. Data b => b -> b) -> Ordering -> Ordering # gmapQl :: (r -> r' -> r) -> r -> (forall d. Data d => d -> r') -> Ordering -> r # gmapQr :: forall r r'. (r' -> r -> r) -> r -> (forall d. Data d => d -> r') -> Ordering -> r # gmapQ :: (forall d. Data d => d -> u) -> Ordering -> [u] # gmapQi :: Int -> (forall d. Data d => d -> u) -> Ordering -> u # gmapM :: Monad m => (forall d. Data d => d -> m d) -> Ordering -> m Ordering # gmapMp :: MonadPlus m => (forall d. Data d => d -> m d) -> Ordering -> m Ordering # gmapMo :: MonadPlus m => (forall d. Data d => d -> m d) -> Ordering -> m Ordering # | |
| Ord Ordering | |
Defined in GHC.Classes | |
| Read Ordering | Since: base-2.1 |
| Show Ordering | Since: base-2.1 |
| Ix Ordering | Since: base-2.1 |
Defined in GHC.Arr Methods range :: (Ordering, Ordering) -> [Ordering] # index :: (Ordering, Ordering) -> Ordering -> Int # unsafeIndex :: (Ordering, Ordering) -> Ordering -> Int # inRange :: (Ordering, Ordering) -> Ordering -> Bool # rangeSize :: (Ordering, Ordering) -> Int # unsafeRangeSize :: (Ordering, Ordering) -> Int # | |
| Generic Ordering | Since: base-4.6.0.0 |
| Semigroup Ordering | Since: base-4.9.0.0 |
| Monoid Ordering | Since: base-2.1 |
| NFData Ordering | |
Defined in Control.DeepSeq | |
| Hashable Ordering | |
Defined in Data.Hashable.Class | |
| type Rep Ordering | |
comparing :: Ord a => (b -> a) -> b -> b -> Ordering #
comparing p x y = compare (p x) (p y)
Useful combinator for use in conjunction with the xxxBy family
of functions from Data.List, for example:
... sortBy (comparing fst) ...
The Down type allows you to reverse sort order conveniently. A value of type
Down aa (represented as Down aa has an Ordthen sortWith by Down x
Since: base-4.6.0.0
Constructors
| Down a |
Instances
| Monad Down | Since: base-4.11.0.0 |
| Functor Down | Since: base-4.11.0.0 |
| Applicative Down | Since: base-4.11.0.0 |
| Foldable Down | Since: base-4.12.0.0 |
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 # elem :: Eq a => a -> Down a -> Bool # maximum :: Ord a => Down a -> a # | |
| Traversable Down | Since: base-4.12.0.0 |
| Eq1 Down | Since: base-4.12.0.0 |
| Ord1 Down | Since: base-4.12.0.0 |
Defined in Data.Functor.Classes | |
| Read1 Down | Since: base-4.12.0.0 |
Defined in Data.Functor.Classes | |
| Show1 Down | Since: base-4.12.0.0 |
| NFData1 Down | Since: deepseq-1.4.3.0 |
Defined in Control.DeepSeq | |
| Eq a => Eq (Down a) | Since: base-4.6.0.0 |
| Data a => Data (Down a) | Since: base-4.12.0.0 |
Defined in Data.Data Methods gfoldl :: (forall d b. Data d => c (d -> b) -> d -> c b) -> (forall g. g -> c g) -> Down a -> c (Down a) # gunfold :: (forall b r. Data b => c (b -> r) -> c r) -> (forall r. r -> c r) -> Constr -> c (Down a) # toConstr :: Down a -> Constr # dataTypeOf :: Down a -> DataType # dataCast1 :: Typeable t => (forall d. Data d => c (t d)) -> Maybe (c (Down a)) # dataCast2 :: Typeable t => (forall d e. (Data d, Data e) => c (t d e)) -> Maybe (c (Down a)) # gmapT :: (forall b. Data b => b -> b) -> Down a -> Down a # gmapQl :: (r -> r' -> r) -> r -> (forall d. Data d => d -> r') -> Down a -> r # gmapQr :: forall r r'. (r' -> r -> r) -> r -> (forall d. Data d => d -> r') -> Down a -> r # gmapQ :: (forall d. Data d => d -> u) -> Down a -> [u] # gmapQi :: Int -> (forall d. Data d => d -> u) -> Down a -> u # gmapM :: Monad m => (forall d. Data d => d -> m d) -> Down a -> m (Down a) # gmapMp :: MonadPlus m => (forall d. Data d => d -> m d) -> Down a -> m (Down a) # gmapMo :: MonadPlus m => (forall d. Data d => d -> m d) -> Down a -> m (Down a) # | |
| Num a => Num (Down a) | Since: base-4.11.0.0 |
| Ord a => Ord (Down a) | Since: base-4.6.0.0 |
| Read a => Read (Down a) | Since: base-4.7.0.0 |
| Show a => Show (Down a) | Since: base-4.7.0.0 |
| Generic (Down a) | Since: base-4.12.0.0 |
| Semigroup a => Semigroup (Down a) | Since: base-4.11.0.0 |
| Monoid a => Monoid (Down a) | Since: base-4.11.0.0 |
| NFData a => NFData (Down a) | Since: deepseq-1.4.0.0 |
Defined in Control.DeepSeq | |
| Generic1 Down | Since: base-4.12.0.0 |
| type Rep (Down a) | |
Defined in GHC.Generics | |
| type Rep1 Down | |
Defined in GHC.Generics | |
System IO
A value of type IO aa.
There is really only one way to "perform" an I/O action: bind it to
Main.main in your program. When your program is run, the I/O will
be performed. It isn't possible to perform I/O from an arbitrary
function, unless that function is itself in the IO monad and called
at some point, directly or indirectly, from Main.main.
IO is a monad, so IO actions can be combined using either the do-notation
or the >> and >>= operations from the Monad
class.
Instances
Haskell defines operations to read and write characters from and to files,
represented by values of type Handle. Each value of this type is a
handle: a record used by the Haskell run-time system to manage I/O
with file system objects. A handle has at least the following properties:
- whether it manages input or output or both;
- whether it is open, closed or semi-closed;
- whether the object is seekable;
- whether buffering is disabled, or enabled on a line or block basis;
- a buffer (whose length may be zero).
Most handles will also have a current I/O position indicating where the next
input or output operation will occur. A handle is readable if it
manages only input or both input and output; likewise, it is writable if
it manages only output or both input and output. A handle is open when
first allocated.
Once it is closed it can no longer be used for either input or output,
though an implementation cannot re-use its storage while references
remain to it. Handles are in the Show and Eq classes. The string
produced by showing a handle is system dependent; it should include
enough information to identify the handle for debugging. A handle is
equal according to == only to itself; no attempt
is made to compare the internal state of different handles for equality.
Instances
withFile :: FilePath -> IOMode -> (Handle -> IO r) -> IO r #
withFile name mode actopenFile and passes
the resulting handle to the computation act. The handle will be
closed on exit from withFile, whether by normal termination or by
raising an exception. If closing the handle raises an exception, then
this exception will be raised by withFile rather than any exception
raised by act.
File and directory names are values of type String, whose precise
meaning is operating system dependent. Files can be opened, yielding a
handle which can then be used to operate on the contents of that file.
See openFile
Constructors
| ReadMode | |
| WriteMode | |
| AppendMode | |
| ReadWriteMode |
Types for type-level computation
coerce :: Coercible a b => a -> b #
The function coerce allows you to safely convert between values of
types that have the same representation with no run-time overhead. In the
simplest case you can use it instead of a newtype constructor, to go from
the newtype's concrete type to the abstract type. But it also works in
more complicated settings, e.g. converting a list of newtypes to a list of
concrete types.
class a ~R# b => Coercible (a :: k) (b :: k) #
Coercible is a two-parameter class that has instances for types a and b if
the compiler can infer that they have the same representation. This class
does not have regular instances; instead they are created on-the-fly during
type-checking. Trying to manually declare an instance of Coercible
is an error.
Nevertheless one can pretend that the following three kinds of instances exist. First, as a trivial base-case:
instance Coercible a a
Furthermore, for every type constructor there is
an instance that allows to coerce under the type constructor. For
example, let D be a prototypical type constructor (data or
newtype) with three type arguments, which have roles nominal,
representational resp. phantom. Then there is an instance of
the form
instance Coercible b b' => Coercible (D a b c) (D a b' c')
Note that the nominal type arguments are equal, the
representational type arguments can differ, but need to have a
Coercible instance themself, and the phantom type arguments can be
changed arbitrarily.
The third kind of instance exists for every newtype NT = MkNT T and
comes in two variants, namely
instance Coercible a T => Coercible a NT
instance Coercible T b => Coercible NT b
This instance is only usable if the constructor MkNT is in scope.
If, as a library author of a type constructor like Set a, you
want to prevent a user of your module to write
coerce :: Set T -> Set NT,
you need to set the role of Set's type parameter to nominal,
by writing
type role Set nominal
For more details about this feature, please refer to Safe Coercions by Joachim Breitner, Richard A. Eisenberg, Simon Peyton Jones and Stephanie Weirich.
Since: ghc-prim-4.7.0.0
data Constraint #
The kind of constraints, like Show a
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 aundefined :: a
>>>Proxy :: Proxy (Void, Int -> Int)Proxy
Proxy can even hold types of higher kinds,
>>>Proxy :: Proxy EitherProxy
>>>Proxy :: Proxy FunctorProxy
>>>Proxy :: Proxy complicatedStructureProxy
Constructors
| Proxy |
Instances
| Generic1 (Proxy :: k -> Type) | Since: base-4.6.0.0 |
| Monad (Proxy :: Type -> Type) | Since: base-4.7.0.0 |
| Functor (Proxy :: Type -> Type) | Since: base-4.7.0.0 |
| Applicative (Proxy :: Type -> Type) | Since: base-4.7.0.0 |
| Foldable (Proxy :: Type -> Type) | Since: base-4.7.0.0 |
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 # elem :: Eq a => a -> Proxy a -> Bool # maximum :: Ord a => Proxy a -> a # minimum :: Ord a => Proxy a -> a # | |
| Traversable (Proxy :: Type -> Type) | Since: base-4.7.0.0 |
| Contravariant (Proxy :: Type -> Type) | |
| Eq1 (Proxy :: Type -> Type) | Since: base-4.9.0.0 |
| Ord1 (Proxy :: Type -> Type) | Since: base-4.9.0.0 |
Defined in Data.Functor.Classes | |
| Read1 (Proxy :: Type -> Type) | Since: base-4.9.0.0 |
Defined in Data.Functor.Classes | |
| Show1 (Proxy :: Type -> Type) | Since: base-4.9.0.0 |
| Alternative (Proxy :: Type -> Type) | Since: base-4.9.0.0 |
| MonadPlus (Proxy :: Type -> Type) | Since: base-4.9.0.0 |
| NFData1 (Proxy :: Type -> Type) | Since: deepseq-1.4.3.0 |
Defined in Control.DeepSeq | |
| Hashable1 (Proxy :: Type -> Type) | |
Defined in Data.Hashable.Class | |
| Bounded (Proxy t) | Since: base-4.7.0.0 |
| Enum (Proxy s) | Since: base-4.7.0.0 |
| Eq (Proxy s) | Since: base-4.7.0.0 |
| Data t => Data (Proxy t) | Since: base-4.7.0.0 |
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 |
| Read (Proxy t) | Since: base-4.7.0.0 |
| Show (Proxy s) | Since: base-4.7.0.0 |
| Ix (Proxy s) | Since: base-4.7.0.0 |
Defined in Data.Proxy | |
| Generic (Proxy t) | Since: base-4.6.0.0 |
| Semigroup (Proxy s) | Since: base-4.9.0.0 |
| Monoid (Proxy s) | Since: base-4.7.0.0 |
| NFData (Proxy a) | Since: deepseq-1.4.0.0 |
Defined in Control.DeepSeq | |
| Hashable (Proxy a) | |
Defined in Data.Hashable.Class | |
| type Rep1 (Proxy :: k -> Type) | |
| type Rep (Proxy t) | |
The class Typeable allows a concrete representation of a type to
be calculated.
Minimal complete definition
typeRep#
Since Void values logically don't exist, this witnesses the
logical reasoning tool of "ex falso quodlibet".
>>>let x :: Either Void Int; x = Right 5>>>:{case x of Right r -> r Left l -> absurd l :} 5
Since: base-4.8.0.0
Uninhabited data type
Since: base-4.8.0.0
Instances
| Eq Void | Since: base-4.8.0.0 |
| Data Void | Since: base-4.8.0.0 |
Defined in Data.Void Methods gfoldl :: (forall d b. Data d => c (d -> b) -> d -> c b) -> (forall g. g -> c g) -> Void -> c Void # gunfold :: (forall b r. Data b => c (b -> r) -> c r) -> (forall r. r -> c r) -> Constr -> c Void # dataTypeOf :: Void -> DataType # dataCast1 :: Typeable t => (forall d. Data d => c (t d)) -> Maybe (c Void) # dataCast2 :: Typeable t => (forall d e. (Data d, Data e) => c (t d e)) -> Maybe (c Void) # gmapT :: (forall b. Data b => b -> b) -> Void -> Void # gmapQl :: (r -> r' -> r) -> r -> (forall d. Data d => d -> r') -> Void -> r # gmapQr :: forall r r'. (r' -> r -> r) -> r -> (forall d. Data d => d -> r') -> Void -> r # gmapQ :: (forall d. Data d => d -> u) -> Void -> [u] # gmapQi :: Int -> (forall d. Data d => d -> u) -> Void -> u # gmapM :: Monad m => (forall d. Data d => d -> m d) -> Void -> m Void # gmapMp :: MonadPlus m => (forall d. Data d => d -> m d) -> Void -> m Void # gmapMo :: MonadPlus m => (forall d. Data d => d -> m d) -> Void -> m Void # | |
| Ord Void | Since: base-4.8.0.0 |
| Read Void | Reading a Since: base-4.8.0.0 |
| Show Void | Since: base-4.8.0.0 |
| Ix Void | Since: base-4.8.0.0 |
| Generic Void | Since: base-4.8.0.0 |
| Semigroup Void | Since: base-4.9.0.0 |
| Lift Void | Since: template-haskell-2.15.0.0 |
| Exception Void | Since: base-4.8.0.0 |
Defined in Data.Void Methods toException :: Void -> SomeException # fromException :: SomeException -> Maybe Void # displayException :: Void -> String # | |
| NFData Void | Since: deepseq-1.4.0.0 |
Defined in Control.DeepSeq | |
| Hashable Void | |
Defined in Data.Hashable.Class | |
| type Rep Void | |
Basic type classes
The value of seq a b is bottom if a is bottom, and
otherwise equal to b. In other words, it evaluates the first
argument a to weak head normal form (WHNF). seq is usually
introduced to improve performance by avoiding unneeded laziness.
A note on evaluation order: the expression seq a b does
not guarantee that a will be evaluated before b.
The only guarantee given by seq is that the both a
and b will be evaluated before seq returns a value.
In particular, this means that b may be evaluated before
a. If you need to guarantee a specific order of evaluation,
you must use the function pseq from the "parallel" package.
($!) :: forall (r :: RuntimeRep) a (b :: TYPE r). (a -> b) -> a -> b infixr 0 #
Strict (call-by-value) application operator. It takes a function and an argument, evaluates the argument to weak head normal form (WHNF), then calls the function with that value.
The Bounded class is used to name the upper and lower limits of a
type. Ord is not a superclass of Bounded since types that are not
totally ordered may also have upper and lower bounds.
The Bounded class may be derived for any enumeration type;
minBound is the first constructor listed in the data declaration
and maxBound is the last.
Bounded may also be derived for single-constructor datatypes whose
constituent types are in Bounded.
Instances
| Bounded Bool | Since: base-2.1 |
| Bounded Char | Since: base-2.1 |
| Bounded Int | Since: base-2.1 |
| Bounded Int8 | Since: base-2.1 |
| Bounded Int16 | Since: base-2.1 |
| Bounded Int32 | Since: base-2.1 |
| Bounded Int64 | Since: base-2.1 |
| Bounded Ordering | Since: base-2.1 |
| Bounded Word | Since: base-2.1 |
| Bounded Word8 | Since: base-2.1 |
| Bounded Word16 | Since: base-2.1 |
| Bounded Word32 | Since: base-2.1 |
| Bounded Word64 | Since: base-2.1 |
| Bounded VecCount | Since: base-4.10.0.0 |
| Bounded VecElem | Since: base-4.10.0.0 |
| Bounded () | Since: base-2.1 |
| Bounded All | Since: base-2.1 |
| Bounded Any | Since: base-2.1 |
| Bounded Associativity | Since: base-4.9.0.0 |
Defined in GHC.Generics | |
| Bounded SourceUnpackedness | Since: base-4.9.0.0 |
Defined in GHC.Generics | |
| Bounded SourceStrictness | Since: base-4.9.0.0 |
Defined in GHC.Generics | |
| Bounded DecidedStrictness | Since: base-4.9.0.0 |
Defined in GHC.Generics | |
| Bounded CChar | |
| Bounded CSChar | |
| Bounded CUChar | |
| Bounded CShort | |
| Bounded CUShort | |
| Bounded CInt | |
| Bounded CUInt | |
| Bounded CLong | |
| Bounded CULong | |
| Bounded CLLong | |
| Bounded CULLong | |
| Bounded CBool | |
| Bounded CPtrdiff | |
| Bounded CSize | |
| Bounded CWchar | |
| Bounded CSigAtomic | |
Defined in Foreign.C.Types | |
| Bounded CIntPtr | |
| Bounded CUIntPtr | |
| Bounded CIntMax | |
| Bounded CUIntMax | |
| Bounded WordPtr | |
| Bounded IntPtr | |
| Bounded Extension | |
| Bounded Undefined Source # | |
| Bounded a => Bounded (Min a) | Since: base-4.9.0.0 |
| Bounded a => Bounded (Max a) | Since: base-4.9.0.0 |
| Bounded a => Bounded (First a) | Since: base-4.9.0.0 |
| Bounded a => Bounded (Last a) | Since: base-4.9.0.0 |
| Bounded m => Bounded (WrappedMonoid m) | Since: base-4.9.0.0 |
Defined in Data.Semigroup | |
| Bounded a => Bounded (Identity a) | Since: base-4.9.0.0 |
| Bounded a => Bounded (Dual a) | Since: base-2.1 |
| Bounded a => Bounded (Sum a) | Since: base-2.1 |
| Bounded a => Bounded (Product a) | Since: base-2.1 |
| (Bounded a, Bounded b) => Bounded (a, b) | Since: base-2.1 |
| Bounded (Proxy t) | Since: base-4.7.0.0 |
| (Bounded a, Bounded b, Bounded c) => Bounded (a, b, c) | Since: base-2.1 |
| Bounded a => Bounded (Const a b) | Since: base-4.9.0.0 |
| (Applicative f, Bounded a) => Bounded (Ap f a) | Since: base-4.12.0.0 |
| a ~ b => Bounded (a :~: b) | Since: base-4.7.0.0 |
| (Bounded a, Bounded b, Bounded c, Bounded d) => Bounded (a, b, c, d) | Since: base-2.1 |
| a ~~ b => Bounded (a :~~: b) | Since: base-4.10.0.0 |
| (Bounded a, Bounded b, Bounded c, Bounded d, Bounded e) => Bounded (a, b, c, d, e) | Since: base-2.1 |
| (Bounded a, Bounded b, Bounded c, Bounded d, Bounded e, Bounded f) => Bounded (a, b, c, d, e, f) | Since: base-2.1 |
| (Bounded a, Bounded b, Bounded c, Bounded d, Bounded e, Bounded f, Bounded g) => Bounded (a, b, c, d, e, f, g) | Since: base-2.1 |
| (Bounded a, Bounded b, Bounded c, Bounded d, Bounded e, Bounded f, Bounded g, Bounded h) => Bounded (a, b, c, d, e, f, g, h) | Since: base-2.1 |
| (Bounded a, Bounded b, Bounded c, Bounded d, Bounded e, Bounded f, Bounded g, Bounded h, Bounded i) => Bounded (a, b, c, d, e, f, g, h, i) | Since: base-2.1 |
| (Bounded a, Bounded b, Bounded c, Bounded d, Bounded e, Bounded f, Bounded g, Bounded h, Bounded i, Bounded j) => Bounded (a, b, c, d, e, f, g, h, i, j) | Since: base-2.1 |
| (Bounded a, Bounded b, Bounded c, Bounded d, Bounded e, Bounded f, Bounded g, Bounded h, Bounded i, Bounded j, Bounded k) => Bounded (a, b, c, d, e, f, g, h, i, j, k) | Since: base-2.1 |
| (Bounded a, Bounded b, Bounded c, Bounded d, Bounded e, Bounded f, Bounded g, Bounded h, Bounded i, Bounded j, Bounded k, Bounded l) => Bounded (a, b, c, d, e, f, g, h, i, j, k, l) | Since: base-2.1 |
| (Bounded a, Bounded b, Bounded c, Bounded d, Bounded e, Bounded f, Bounded g, Bounded h, Bounded i, Bounded j, Bounded k, Bounded l, Bounded m) => Bounded (a, b, c, d, e, f, g, h, i, j, k, l, m) | Since: base-2.1 |
| (Bounded a, Bounded b, Bounded c, Bounded d, Bounded e, Bounded f, Bounded g, Bounded h, Bounded i, Bounded j, Bounded k, Bounded l, Bounded m, Bounded n) => Bounded (a, b, c, d, e, f, g, h, i, j, k, l, m, n) | Since: base-2.1 |
| (Bounded a, Bounded b, Bounded c, Bounded d, Bounded e, Bounded f, Bounded g, Bounded h, Bounded i, Bounded j, Bounded k, Bounded l, Bounded m, Bounded n, Bounded o) => Bounded (a, b, c, d, e, f, g, h, i, j, k, l, m, n, o) | Since: base-2.1 |
Class Enum defines operations on sequentially ordered types.
The enumFrom... methods are used in Haskell's translation of
arithmetic sequences.
Instances of Enum may be derived for any enumeration type (types
whose constructors have no fields). The nullary constructors are
assumed to be numbered left-to-right by fromEnum from 0 through n-1.
See Chapter 10 of the Haskell Report for more details.
For any type that is an instance of class Bounded as well as Enum,
the following should hold:
- The calls
succmaxBoundpredminBound fromEnumandtoEnumshould give a runtime error if the result value is not representable in the result type. For example,toEnum7 ::BoolenumFromandenumFromThenshould be defined with an implicit bound, thus:
enumFrom x = enumFromTo x maxBound
enumFromThen x y = enumFromThenTo x y bound
where
bound | fromEnum y >= fromEnum x = maxBound
| otherwise = minBoundMethods
the successor of a value. For numeric types, succ adds 1.
the predecessor of a value. For numeric types, pred subtracts 1.
Convert from an Int.
Convert to an Int.
It is implementation-dependent what fromEnum returns when
applied to a value that is too large to fit in an Int.
Used in Haskell's translation of [n..] with [n..] = enumFrom n,
a possible implementation being enumFrom n = n : enumFrom (succ n).
For example:
enumFrom 4 :: [Integer] = [4,5,6,7,...]
enumFrom 6 :: [Int] = [6,7,8,9,...,maxBound :: Int]
enumFromThen :: a -> a -> [a] #
Used in Haskell's translation of [n,n'..]
with [n,n'..] = enumFromThen n n', a possible implementation being
enumFromThen n n' = n : n' : worker (f x) (f x n'),
worker s v = v : worker s (s v), x = fromEnum n' - fromEnum n and
f n y
| n > 0 = f (n - 1) (succ y)
| n < 0 = f (n + 1) (pred y)
| otherwise = y
For example:
enumFromThen 4 6 :: [Integer] = [4,6,8,10...]
enumFromThen 6 2 :: [Int] = [6,2,-2,-6,...,minBound :: Int]
enumFromTo :: a -> a -> [a] #
Used in Haskell's translation of [n..m] with
[n..m] = enumFromTo n m, a possible implementation being
enumFromTo n m
| n <= m = n : enumFromTo (succ n) m
| otherwise = [].
For example:
enumFromTo 6 10 :: [Int] = [6,7,8,9,10]
enumFromTo 42 1 :: [Integer] = []
enumFromThenTo :: a -> a -> a -> [a] #
Used in Haskell's translation of [n,n'..m] with
[n,n'..m] = enumFromThenTo n n' m, a possible implementation
being enumFromThenTo n n' m = worker (f x) (c x) n m,
x = fromEnum n' - fromEnum n, c x = bool (>=) ((x 0)
f n y
| n > 0 = f (n - 1) (succ y)
| n < 0 = f (n + 1) (pred y)
| otherwise = y and
worker s c v m
| c v m = v : worker s c (s v) m
| otherwise = []
For example:
enumFromThenTo 4 2 -6 :: [Integer] = [4,2,0,-2,-4,-6]
enumFromThenTo 6 8 2 :: [Int] = []
Instances
boundedEnumFromThen :: (Enum a, Bounded a) => a -> a -> [a] #
boundedEnumFrom :: (Enum a, Bounded a) => a -> [a] #
Representable types of kind *.
This class is derivable in GHC with the DeriveGeneric flag on.
A Generic instance must satisfy the following laws:
from.to≡idto.from≡id
Instances
Conversion of values to readable Strings.
Derived instances of Show have the following properties, which
are compatible with derived instances of Read:
- The result of
showis a syntactically correct Haskell expression containing only constants, given the fixity declarations in force at the point where the type is declared. It contains only the constructor names defined in the data type, parentheses, and spaces. When labelled constructor fields are used, braces, commas, field names, and equal signs are also used. - If the constructor is defined to be an infix operator, then
showsPrecwill produce infix applications of the constructor. - the representation will be enclosed in parentheses if the
precedence of the top-level constructor in
xis less thand(associativity is ignored). Thus, ifdis0then the result is never surrounded in parentheses; ifdis11it is always surrounded in parentheses, unless it is an atomic expression. - If the constructor is defined using record syntax, then
showwill produce the record-syntax form, with the fields given in the same order as the original declaration.
For example, given the declarations
infixr 5 :^: data Tree a = Leaf a | Tree a :^: Tree a
the derived instance of Show is equivalent to
instance (Show a) => Show (Tree a) where
showsPrec d (Leaf m) = showParen (d > app_prec) $
showString "Leaf " . showsPrec (app_prec+1) m
where app_prec = 10
showsPrec d (u :^: v) = showParen (d > up_prec) $
showsPrec (up_prec+1) u .
showString " :^: " .
showsPrec (up_prec+1) v
where up_prec = 5Note that right-associativity of :^: is ignored. For example,
show(Leaf 1 :^: Leaf 2 :^: Leaf 3)"Leaf 1 :^: (Leaf 2 :^: Leaf 3)".
Instances
GHC-specific functionality
This class gives the integer associated with a type-level natural. There are instances of the class for every concrete literal: 0, 1, 2, etc.
Since: base-4.7.0.0
Minimal complete definition
natSing
type family CmpNat (a :: Nat) (b :: Nat) :: Ordering where ... #
Comparison of type-level naturals, as a function.
Since: base-4.7.0.0
someNatVal :: Natural -> SomeNat #
Convert an integer into an unknown type-level natural.
Since: base-4.10.0.0
This type represents unknown type-level natural numbers.
Since: base-4.10.0.0
showStackTrace :: IO (Maybe String) #
Get a string representation of the current execution stack state.
getStackTrace :: IO (Maybe [Location]) #
Get a trace of the current execution stack state.
Returns Nothing if stack trace support isn't available on host machine.
CallStacks are a lightweight method of obtaining a
partial call-stack at any point in the program.
A function can request its call-site with the HasCallStack constraint.
For example, we can define
putStrLnWithCallStack :: HasCallStack => String -> IO ()
as a variant of putStrLn that will get its call-site and print it,
along with the string given as argument. We can access the
call-stack inside putStrLnWithCallStack with callStack.
putStrLnWithCallStack :: HasCallStack => String -> IO () putStrLnWithCallStack msg = do putStrLn msg putStrLn (prettyCallStack callStack)
Thus, if we call putStrLnWithCallStack we will get a formatted call-stack
alongside our string.
>>>putStrLnWithCallStack "hello"hello CallStack (from HasCallStack): putStrLnWithCallStack, called at <interactive>:2:1 in interactive:Ghci1
GHC solves HasCallStack constraints in three steps:
- If there is a
CallStackin scope -- i.e. the enclosing function has aHasCallStackconstraint -- GHC will append the new call-site to the existingCallStack. - If there is no
CallStackin scope -- e.g. in the GHCi session above -- and the enclosing definition does not have an explicit type signature, GHC will infer aHasCallStackconstraint for the enclosing definition (subject to the monomorphism restriction). - If there is no
CallStackin scope and the enclosing definition has an explicit type signature, GHC will solve theHasCallStackconstraint for the singletonCallStackcontaining just the current call-site.
CallStacks do not interact with the RTS and do not require compilation
with -prof. On the other hand, as they are built up explicitly via the
HasCallStack constraints, they will generally not contain as much
information as the simulated call-stacks maintained by the RTS.
A CallStack is a [(String, SrcLoc)]. The String is the name of
function that was called, the SrcLoc is the call-site. The list is
ordered with the most recently called function at the head.
NOTE: The intrepid user may notice that HasCallStack is just an
alias for an implicit parameter ?callStack :: CallStack. This is an
implementation detail and should not be considered part of the
CallStack API, we may decide to change the implementation in the
future.
Since: base-4.8.1.0
withFrozenCallStack :: HasCallStack => (HasCallStack => a) -> a #
Perform some computation without adding new entries to the CallStack.
Since: base-4.9.0.0
callStack :: HasCallStack => CallStack #
prettyCallStack :: CallStack -> String #
Pretty print a CallStack.
Since: base-4.9.0.0
prettySrcLoc :: SrcLoc -> String #
Pretty print a SrcLoc.
Since: base-4.9.0.0
currentCallStack :: IO [String] #
Returns a [String] representing the current call stack. This
can be useful for debugging.
The implementation uses the call-stack simulation maintained by the
profiler, so it only works if the program was compiled with -prof
and contains suitable SCC annotations (e.g. by using -fprof-auto).
Otherwise, the list returned is likely to be empty or
uninformative.
Since: base-4.5.0.0
getCallStack :: CallStack -> [([Char], SrcLoc)] #
Extract a list of call-sites from the CallStack.
The list is ordered by most recent call.
Since: base-4.8.1.0
type HasCallStack = ?callStack :: CallStack #
Request a CallStack.
NOTE: The implicit parameter ?callStack :: CallStack is an
implementation detail and should not be considered part of the
CallStack API, we may decide to change the implementation in the
future.
Since: base-4.9.0.0