| Safe Haskell | None |
|---|---|
| Language | Haskell2010 |
Chassis
Synopsis
- data Void
- absurd :: Void -> a
- data Bool
- not :: Bool -> Bool
- data Int
- type String = [Char]
- data ByteString
- data Text
- class Show a where
- class Semigroup a where
- (<>) :: a -> a -> a
- class Semigroup a => Monoid a where
- mempty :: a
- class Eq a where
- class Eq a => Ord a where
- ($) :: forall (r :: RuntimeRep) a (b :: TYPE r). (a -> b) -> a -> b
- (&) :: a -> (a -> b) -> b
- data IO a
- data Maybe a
- maybe :: b -> (a -> b) -> Maybe a -> b
- data Either a b
- either :: (a -> c) -> (b -> c) -> Either a b -> c
- data NonEmpty a = a :| [a]
- data Map k a
- fst :: (a, b) -> a
- snd :: (a, b) -> b
- const :: a -> b -> a
- curry :: ((a, b) -> c) -> a -> b -> c
- uncurry :: (a -> b -> c) -> (a, b) -> c
- class Foldable (t :: Type -> Type) where
- class Functor (f :: Type -> Type) where
- ($>) :: Functor f => f a -> b -> f b
- (<$>) :: Functor f => (a -> b) -> f a -> f b
- void :: Functor f => f a -> f ()
- class Functor f => Applicative (f :: Type -> Type) where
- when :: Applicative f => Bool -> f () -> f ()
- unless :: Applicative f => Bool -> f () -> f ()
- whenM :: Monad m => m Bool -> m () -> m ()
- whenJust :: Applicative m => Maybe a -> (a -> m ()) -> m ()
- class (Functor t, Foldable t) => Traversable (t :: Type -> Type) where
- traverse_ :: (Foldable t, Applicative f) => (a -> f b) -> t a -> f ()
- for_ :: (Foldable t, Applicative f) => t a -> (a -> f b) -> f ()
- filterM :: Applicative m => (a -> m Bool) -> [a] -> m [a]
- class Applicative m => Monad (m :: Type -> Type) where
- join :: Monad m => m (m a) -> m a
- forM_ :: (Foldable t, Monad m) => t a -> (a -> m b) -> m ()
- forM :: (Traversable t, Monad m) => t a -> (a -> m b) -> m (t b)
- mapM_ :: (Foldable t, Monad m) => (a -> m b) -> t a -> m ()
- sequence_ :: (Foldable t, Monad m) => t (m a) -> m ()
- (=<<) :: Monad m => (a -> m b) -> m a -> m b
- (>=>) :: Monad m => (a -> m b) -> (b -> m c) -> a -> m c
- class Contravariant (f :: Type -> Type) where
- contramap :: (a -> b) -> f b -> f a
- (>$<) :: Contravariant f => (a -> b) -> f b -> f a
- data Predicate a
- data Equivalence a
- data Comparison a
- data Op a b
- class Functor g => Distributive (g :: Type -> Type) where
- distribute :: Functor f => f (g a) -> g (f a)
- class Functor w => Comonad (w :: Type -> Type) where
- (=>=) :: Comonad w => (w a -> b) -> (w b -> c) -> w a -> c
- (<<=) :: Comonad w => (w a -> b) -> w a -> w b
- class Profunctor (p :: Type -> Type -> Type) where
- class Profunctor p => Strong (p :: Type -> Type -> Type) where
- class Profunctor p => Choice (p :: Type -> Type -> Type) where
- class Category (cat :: k -> k -> Type) where
- class Category a => Arrow (a :: Type -> Type -> Type) where
- data Kleisli (m :: Type -> Type) a b
- (>>>) :: forall k cat (a :: k) (b :: k) (c :: k). Category cat => cat a b -> cat b c -> cat a c
- (<<<) :: forall k cat (b :: k) (c :: k) (a :: k). Category cat => cat b c -> cat a b -> cat a c
- type Env e = EnvT e Identity
- data EnvT e (w :: Type -> Type) a = EnvT e (w a)
- env :: e -> a -> Env e a
- runEnv :: Env e a -> (e, a)
- runEnvT :: EnvT e w a -> (e, w a)
- data Rec (a :: u -> Type) (b :: [u]) where
- class RMap (rs :: [u])
- rtraverse :: forall u h f g (rs :: [u]). Applicative h => (forall (x :: u). f x -> h (g x)) -> Rec f rs -> h (Rec g rs)
- rcast :: forall k1 k2 (rs :: [k1]) (ss :: [k1]) (f :: k2 -> Type) record (is :: [Nat]). (RecSubset record rs ss is, RecSubsetFCtx record f) => record f ss -> record f rs
- data CoRec (a :: u -> Type) (b :: [u]) where
- type (∈) (r :: k) (rs :: [k]) = RElem r rs (RIndex r rs)
- type (:.) (f :: l -> Type) (g :: k -> l) = Compose f g
- data Compose (f :: l -> Type) (g :: k -> l) (x :: k)
- onCompose :: forall l1 k1 l2 f (g :: k1 -> l1) (a :: k1) h (k2 :: k1 -> l2). (f (g a) -> h (k2 a)) -> (f :. g) a -> (h :. k2) a
- class Generic a
- data UTCTime
- data Path b t
- data Rel
- data Abs
- data File
- data Dir
- mkRelDir :: FilePath -> Q Exp
- mkRelFile :: FilePath -> Q Exp
- mkAbsDir :: FilePath -> Q Exp
- mkAbsFile :: FilePath -> Q Exp
- (</>) :: Path b Dir -> Path Rel t -> Path b t
- flip :: (a -> b -> c) -> b -> a -> c
- rights :: [Either a b] -> [b]
- type Type = Type
- data Constraint
- type Exp a = a -> Type
- type family Eval (e :: Exp a) :: a
- type FMap = Map :: (a -> Exp b) -> f a -> f b -> Type
- class (Typeable e, Show e) => Exception e where
- displayException :: e -> String
- data SomeException
Void
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 |
| Hashable Void | |
Defined in Data.Hashable.Class | |
| Exception Void | Since: base-4.8.0.0 |
Defined in Data.Void Methods toException :: Void -> SomeException # fromException :: SomeException -> Maybe Void # displayException :: Void -> String # | |
| Lift Void | Since: template-haskell-2.15.0.0 |
| type Rep Void | |
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
Bool
Instances
Numbers
A fixed-precision integer type with at least the range [-2^29 .. 2^29-1].
The exact range for a given implementation can be determined by using
minBound and maxBound from the Bounded class.
Instances
StringTextByteString
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
A space efficient, packed, unboxed Unicode text type.
Instances
| Hashable Text | |
Defined in Data.Hashable.Class | |
| Chunk Text | |
Defined in Data.Attoparsec.Internal.Types | |
| Ixed Text | |
Defined in Control.Lens.At | |
| type State Text | |
Defined in Data.Attoparsec.Internal.Types | |
| type ChunkElem Text | |
Defined in Data.Attoparsec.Internal.Types | |
| type Item Text | |
| type Index Text | |
Defined in Control.Lens.At | |
| type IxValue Text | |
Defined in Control.Lens.At | |
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,
produces the stringshow(Leaf 1 :^: Leaf 2 :^: Leaf 3)"Leaf 1 :^: (Leaf 2 :^: Leaf 3)".
Methods
Instances
Classic Algebra
The class of semigroups (types with an associative binary operation).
Instances should satisfy the following:
Since: base-4.9.0.0
Instances
class Semigroup a => Monoid a where #
The class of monoids (types with an associative binary operation that has an identity). Instances should satisfy the following:
- Right identity
x<>mempty= x- Left identity
mempty<>x = x- Associativity
x(<>(y<>z) = (x<>y)<>zSemigrouplaw)- Concatenation
mconcat=foldr(<>)mempty
The method names refer to the monoid of lists under concatenation, but there are many other instances.
Some types can be viewed as a monoid in more than one way,
e.g. both addition and multiplication on numbers.
In such cases we often define newtypes and make those instances
of Monoid, e.g. Sum and Product.
NOTE: Semigroup is a superclass of Monoid since base-4.11.0.0.
Instances
| Monoid Ordering | Since: base-2.1 |
| Monoid () | Since: base-2.1 |
| Monoid ByteString | |
Defined in Data.ByteString.Internal Methods mempty :: ByteString # mappend :: ByteString -> ByteString -> ByteString # mconcat :: [ByteString] -> ByteString # | |
| Monoid More | |
| Monoid IntSet | |
| Monoid Doc | |
| Monoid ByteArray | |
| Monoid [a] | Since: base-2.1 |
| Semigroup a => Monoid (Maybe a) | Lift a semigroup into Since 4.11.0: constraint on inner Since: base-2.1 |
| Monoid a => Monoid (IO a) | Since: base-4.9.0.0 |
| Monoid p => Monoid (Par1 p) | Since: base-4.12.0.0 |
| Monoid (IResult a) | |
| Monoid (Result a) | |
| Monoid (Parser a) | |
| Monoid (Predicate a) | |
| Monoid (Comparison a) | |
Defined in Data.Functor.Contravariant Methods mempty :: Comparison a # mappend :: Comparison a -> Comparison a -> Comparison a # mconcat :: [Comparison a] -> Comparison a # | |
| Monoid (Equivalence a) | |
Defined in Data.Functor.Contravariant Methods mempty :: Equivalence a # mappend :: Equivalence a -> Equivalence a -> Equivalence a # mconcat :: [Equivalence a] -> Equivalence a # | |
| (Ord a, Bounded a) => Monoid (Min a) | Since: base-4.9.0.0 |
| (Ord a, Bounded a) => Monoid (Max a) | Since: base-4.9.0.0 |
| Monoid m => Monoid (WrappedMonoid m) | Since: base-4.9.0.0 |
Defined in Data.Semigroup Methods mempty :: WrappedMonoid m # mappend :: WrappedMonoid m -> WrappedMonoid m -> WrappedMonoid m # mconcat :: [WrappedMonoid m] -> WrappedMonoid m # | |
| Semigroup a => Monoid (Option a) | Since: base-4.9.0.0 |
| Monoid (IntMap a) | |
| Monoid (Seq a) | |
| Ord a => Monoid (Set a) | |
| Monoid (DList a) | |
| Prim a => Monoid (Vector a) | |
| Storable a => Monoid (Vector a) | |
| (Hashable a, Eq a) => Monoid (HashSet a) | O(n+m) To obtain good performance, the smaller set must be presented as the first argument. Examples
|
| Monoid (Vector a) | |
| Monoid (Doc a) | |
| Monoid (PrimArray a) | Since: primitive-0.6.4.0 |
| Monoid (SmallArray a) | |
Defined in Data.Primitive.SmallArray Methods mempty :: SmallArray a # mappend :: SmallArray a -> SmallArray a -> SmallArray a # mconcat :: [SmallArray a] -> SmallArray a # | |
| Monoid (Array a) | |
| Semigroup a => Monoid (Maybe a) | |
| (KnownSymbol s, Monoid t) => Monoid (ElField '(s, t)) | |
| Monoid (MergeSet a) | |
| Monoid b => Monoid (a -> b) | Since: base-2.1 |
| Monoid (U1 p) | Since: base-4.12.0.0 |
| (Monoid a, Monoid b) => Monoid (a, b) | Since: base-2.1 |
| Monoid a => Monoid (Op a b) | |
| (Eq k, Hashable k) => Monoid (HashMap k v) | If a key occurs in both maps, the mapping from the first will be the mapping in the result. Examples
|
| Ord k => Monoid (Map k v) | |
| Monoid (Parser i a) | |
| Monoid a => Monoid (s :-> a) | |
| Monoid (ReifiedFold s a) | |
Defined in Control.Lens.Reified Methods mempty :: ReifiedFold s a # mappend :: ReifiedFold s a -> ReifiedFold s a -> ReifiedFold s a # mconcat :: [ReifiedFold s a] -> ReifiedFold s a # | |
| Monoid (f a) => Monoid (Indexing f a) |
|
| (Monoid a, Monoid b) => Monoid (Pair a b) | |
| Monoid (f p) => Monoid (Rec1 f p) | Since: base-4.12.0.0 |
| (Monoid a, Monoid b, Monoid c) => Monoid (a, b, c) | Since: base-2.1 |
| Monoid (Rec f ('[] :: [u])) | |
| (Monoid (f r), Monoid (Rec f rs)) => Monoid (Rec f (r ': rs)) | |
| (Semigroup a, Monoid a) => Monoid (Tagged s a) | |
| Monoid (ReifiedIndexedFold i s a) | |
Defined in Control.Lens.Reified Methods mempty :: ReifiedIndexedFold i s a # mappend :: ReifiedIndexedFold i s a -> ReifiedIndexedFold i s a -> ReifiedIndexedFold i s a # mconcat :: [ReifiedIndexedFold i s a] -> ReifiedIndexedFold i s a # | |
| ArrowPlus p => Monoid (Tambara p a b) | |
| Reifies s (ReifiedMonoid a) => Monoid (ReflectedMonoid a s) | |
Defined in Data.Reflection Methods mempty :: ReflectedMonoid a s # mappend :: ReflectedMonoid a s -> ReflectedMonoid a s -> ReflectedMonoid a s # mconcat :: [ReflectedMonoid a s] -> ReflectedMonoid a s # | |
| Monoid c => Monoid (K1 i c p) | Since: base-4.12.0.0 |
| (Monoid (f p), Monoid (g p)) => Monoid ((f :*: g) p) | Since: base-4.12.0.0 |
| (Monoid a, Monoid b, Monoid c, Monoid d) => Monoid (a, b, c, d) | Since: base-2.1 |
| Monoid (f p) => Monoid (M1 i c f p) | Since: base-4.12.0.0 |
| Monoid (f (g p)) => Monoid ((f :.: g) p) | Since: base-4.12.0.0 |
| (Monoid a, Monoid b, Monoid c, Monoid d, Monoid e) => Monoid (a, b, c, d, e) | Since: base-2.1 |
| Monoid (f (g a)) => Monoid (Compose f g a) | |
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 Integer | |
| Eq Ordering | |
| Eq Word | |
| 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 ByteString | |
Defined in Data.ByteString.Internal | |
| Eq Scientific | Scientific numbers can be safely compared for equality. No magnitude |
Defined in Data.Scientific | |
| Eq UTCTime | |
| Eq JSONPathElement | |
Defined in Data.Aeson.Types.Internal Methods (==) :: JSONPathElement -> JSONPathElement -> Bool # (/=) :: JSONPathElement -> JSONPathElement -> Bool # | |
| Eq Value | |
| Eq DotNetTime | |
Defined in Data.Aeson.Types.Internal | |
| Eq SumEncoding | |
Defined in Data.Aeson.Types.Internal | |
| Eq Pos | |
| Eq More | |
| 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 Version | Since: base-2.1 |
| 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 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 ArithException | Since: base-3.0 |
Defined in GHC.Exception.Type Methods (==) :: ArithException -> ArithException -> Bool # (/=) :: ArithException -> ArithException -> Bool # | |
| 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 IntSet | |
| Eq Extension | |
| Eq ForeignSrcLang | |
Defined in GHC.ForeignSrcLang.Type Methods (==) :: ForeignSrcLang -> ForeignSrcLang -> Bool # (/=) :: ForeignSrcLang -> ForeignSrcLang -> Bool # | |
| Eq BigNat | |
| Eq Stmt | |
| Eq ModName | |
| Eq Phases | |
| Eq RuleBndr | |
| Eq Pragma | |
| Eq DerivClause | |
Defined in Language.Haskell.TH.Syntax | |
| Eq DerivStrategy | |
Defined in Language.Haskell.TH.Syntax Methods (==) :: DerivStrategy -> DerivStrategy -> Bool # (/=) :: DerivStrategy -> DerivStrategy -> Bool # | |
| Eq TySynEqn | |
| Eq Fixity | |
| Eq Info | |
| Eq Con | |
| Eq TyVarBndr | |
| Eq PathException | |
Defined in Path.Posix Methods (==) :: PathException -> PathException -> Bool # (/=) :: PathException -> PathException -> Bool # | |
| Eq Doc | |
| Eq TextDetails | |
Defined in Text.PrettyPrint.Annotated.HughesPJ | |
| Eq Style | |
| Eq Mode | |
| Eq ByteArray | Since: primitive-0.6.3.0 |
| Eq StdGen | |
| Eq PkgName | |
| Eq Module | |
| Eq OccName | |
| Eq NameFlavour | |
Defined in Language.Haskell.TH.Syntax | |
| Eq NameSpace | |
| Eq Loc | |
| Eq ModuleInfo | |
Defined in Language.Haskell.TH.Syntax | |
| Eq FixityDirection | |
Defined in Language.Haskell.TH.Syntax Methods (==) :: FixityDirection -> FixityDirection -> Bool # (/=) :: FixityDirection -> FixityDirection -> Bool # | |
| Eq Lit | |
| Eq Bytes | |
| Eq Body | |
| Eq Guard | |
| Eq Range | |
| Eq TypeFamilyHead | |
Defined in Language.Haskell.TH.Syntax Methods (==) :: TypeFamilyHead -> TypeFamilyHead -> Bool # (/=) :: TypeFamilyHead -> TypeFamilyHead -> Bool # | |
| Eq Foreign | |
| Eq Callconv | |
| Eq Safety | |
| Eq Inline | |
| Eq RuleMatch | |
| 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 Bang | |
| Eq PatSynDir | |
| Eq PatSynArgs | |
Defined in Language.Haskell.TH.Syntax | |
| Eq FamilyResultSig | |
Defined in Language.Haskell.TH.Syntax Methods (==) :: FamilyResultSig -> FamilyResultSig -> Bool # (/=) :: FamilyResultSig -> FamilyResultSig -> Bool # | |
| Eq TyLit | |
| Eq Role | |
| Eq AnnLookup | |
| Eq DatatypeInfo | |
Defined in Language.Haskell.TH.Datatype | |
| Eq DatatypeVariant | |
Defined in Language.Haskell.TH.Datatype Methods (==) :: DatatypeVariant -> DatatypeVariant -> Bool # (/=) :: DatatypeVariant -> DatatypeVariant -> Bool # | |
| Eq ConstructorInfo | |
Defined in Language.Haskell.TH.Datatype Methods (==) :: ConstructorInfo -> ConstructorInfo -> Bool # (/=) :: ConstructorInfo -> ConstructorInfo -> Bool # | |
| Eq ConstructorVariant | |
Defined in Language.Haskell.TH.Datatype Methods (==) :: ConstructorVariant -> ConstructorVariant -> Bool # (/=) :: ConstructorVariant -> ConstructorVariant -> Bool # | |
| Eq FieldStrictness | |
Defined in Language.Haskell.TH.Datatype Methods (==) :: FieldStrictness -> FieldStrictness -> Bool # (/=) :: FieldStrictness -> FieldStrictness -> Bool # | |
| Eq Unpackedness | |
Defined in Language.Haskell.TH.Datatype | |
| Eq Strictness | |
Defined in Language.Haskell.TH.Datatype | |
| Eq Specificity | |
Defined in Language.Haskell.TH.Datatype.TyVarBndr | |
| Eq LocalTime | |
| Eq DiffTime | |
| Eq Day | |
| Eq UnpackedUUID | |
| Eq UUID | |
| Eq a => Eq [a] | |
| Eq a => Eq (Maybe a) | Since: base-2.1 |
| Eq a => Eq (Ratio a) | Since: base-2.1 |
| Eq p => Eq (Par1 p) | Since: base-4.7.0.0 |
| Eq a => Eq (IResult a) | |
| Eq a => Eq (Result a) | |
| Eq a => Eq (Complex 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 a => Eq (ZipList a) | Since: base-4.7.0.0 |
| 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) | |
| Eq1 f => Eq (Fix f) | |
| (Functor f, Eq1 f) => Eq (Mu f) | |
| (Functor f, Eq1 f) => Eq (Nu f) | |
| Eq a => Eq (DNonEmpty a) | |
| Eq a => Eq (DList a) | |
| Eq a => Eq (Hashed a) | Uses precomputed hash to detect inequality faster |
| (Prim a, Eq a) => Eq (Vector a) | |
| (Storable a, Eq a) => Eq (Vector a) | |
| Eq a => Eq (HashSet a) | Note that, in the presence of hash collisions, equal
In general, the lack of substitutivity can be observed with any function that depends on the key ordering, such as folds and traversals. |
| Eq a => Eq (Vector a) | |
| Eq (SomeBase t) | |
| Eq (Doc a) | |
| Eq a => Eq (AnnotDetails a) | |
Defined in Text.PrettyPrint.Annotated.HughesPJ Methods (==) :: AnnotDetails a -> AnnotDetails a -> Bool # (/=) :: AnnotDetails a -> AnnotDetails a -> Bool # | |
| Eq a => Eq (Span a) | |
| (Eq a, Prim a) => Eq (PrimArray a) | Since: primitive-0.6.4.0 |
| Eq (MutableByteArray s) | |
Defined in Data.Primitive.ByteArray Methods (==) :: MutableByteArray s -> MutableByteArray s -> Bool # (/=) :: MutableByteArray s -> MutableByteArray s -> Bool # | |
| Eq a => Eq (SmallArray a) | |
Defined in Data.Primitive.SmallArray | |
| Eq a => Eq (Array a) | |
| Eq g => Eq (AtomicGen g) | |
| Eq g => Eq (IOGen g) | |
| Eq g => Eq (STGen g) | |
| Eq g => Eq (StateGen g) | |
| Eq a => Eq (Maybe a) | |
| Eq a => Eq (Identity a) | |
| Eq t => Eq (ElField '(s, t)) | |
| (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 a, Eq b) => Eq (a, b) | |
| (Eq k, Eq v) => Eq (HashMap k v) | Note that, in the presence of hash collisions, equal
In general, the lack of substitutivity can be observed with any function that depends on the key ordering, such as folds and traversals. |
| (Eq k, Eq a) => Eq (Map k a) | |
| Eq a => Eq (Arg a b) | Since: base-4.9.0.0 |
| Eq a => Eq (s :-> a) | |
| (Eq1 f, Eq a) => Eq (Cofree f a) | |
| (Eq1 f, Eq a) => Eq (Free f a) | |
| (Eq1 f, Eq a) => Eq (Yoneda f a) | |
| Eq (Path b t) | String equality. The following property holds: show x == show y ≡ x == y |
| Eq (MutablePrimArray s a) | |
Defined in Data.Primitive.PrimArray Methods (==) :: MutablePrimArray s a -> MutablePrimArray s a -> Bool # (/=) :: MutablePrimArray s a -> MutablePrimArray s a -> Bool # | |
| Eq (SmallMutableArray s a) | |
Defined in Data.Primitive.SmallArray Methods (==) :: SmallMutableArray s a -> SmallMutableArray s a -> Bool # (/=) :: SmallMutableArray s a -> SmallMutableArray s a -> Bool # | |
| Eq (MutableArray s a) | |
Defined in Data.Primitive.Array Methods (==) :: MutableArray s a -> MutableArray s a -> Bool # (/=) :: MutableArray s a -> MutableArray s a -> Bool # | |
| (Eq a, Eq b) => Eq (Pair a b) | |
| (Eq a, Eq b) => Eq (These a b) | |
| (Eq a, Eq b) => Eq (Either a b) | |
| (Eq a, Eq b) => Eq (These a b) | |
| (Eq k, Eq v) => Eq (Leaf k v) | |
| 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 (p a a) => Eq (Join p a) | |
| Eq (p (Fix p a) a) => Eq (Fix p a) | |
| Eq a => Eq (Const a b) | |
| (RMap rs, RecAll Maybe rs Eq, RecApplicative rs, RecordToList rs, ReifyConstraint Eq Maybe rs) => Eq (CoRec Identity rs) | |
| Eq (Rec f ('[] :: [u])) | |
| (Eq (f r), Eq (Rec f rs)) => Eq (Rec f (r ': rs)) | |
| (Eq a, Eq (f b)) => Eq (FreeF f a b) | |
| (Eq1 f, Eq1 m, Eq a) => Eq (FreeT f m a) | |
| (Eq a, Eq (f b)) => Eq (CofreeF f a b) | |
| Eq (w (CofreeF f a (CofreeT f w a))) => Eq (CofreeT f w a) | |
| (Eq e, Eq1 m, Eq a) => Eq (ErrorT e m a) | |
| Eq b => Eq (Tagged s b) | |
| (Eq1 f, Eq1 g, Eq a) => Eq (These1 f g a) | |
| (RPureConstrained (IndexableField rs) rs, RecApplicative rs, Eq (Rec f rs)) => Eq (ARec f rs) | |
| 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 (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 (p a b) => Eq (WrappedBifunctor p a b) | |
Defined in Data.Bifunctor.Wrapped Methods (==) :: WrappedBifunctor p a b -> WrappedBifunctor p a b -> Bool # (/=) :: WrappedBifunctor p a b -> WrappedBifunctor p a b -> Bool # | |
| Eq (g b) => Eq (Joker g a b) | |
| Eq (p b a) => Eq (Flip p a b) | |
| Eq (f a) => Eq (Clown f a b) | |
| (Eq a, Eq b, Eq c, Eq d, Eq e, Eq f) => Eq (a, b, c, d, e, f) | |
| (Eq (p a b), Eq (q a b)) => Eq (Sum p q a b) | |
| (Eq (f a b), Eq (g a b)) => Eq (Product f g a b) | |
| (Eq a, Eq b, Eq c, Eq d, Eq e, Eq f, Eq g) => Eq (a, b, c, d, e, f, g) | |
| Eq (f (p a b)) => Eq (Tannen f p a b) | |
| (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 (p (f a) (g b)) => Eq (Biff p f g a b) | |
| (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
Note that (7.) and (8.) do not require min and max to return either of
their arguments. The result is merely required to equal one of the
arguments in terms of (==).
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 Integer | |
| Ord Ordering | |
Defined in GHC.Classes | |
| Ord Word | |
| 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 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 Scientific | Scientific numbers can be safely compared for ordering. No magnitude |
Defined in Data.Scientific Methods compare :: Scientific -> Scientific -> Ordering # (<) :: Scientific -> Scientific -> Bool # (<=) :: Scientific -> Scientific -> Bool # (>) :: Scientific -> Scientific -> Bool # (>=) :: Scientific -> Scientific -> Bool # max :: Scientific -> Scientific -> Scientific # min :: Scientific -> Scientific -> Scientific # | |
| Ord UTCTime | |
Defined in Data.Time.Clock.Internal.UTCTime | |
| Ord JSONPathElement | |
Defined in Data.Aeson.Types.Internal Methods compare :: JSONPathElement -> JSONPathElement -> Ordering # (<) :: JSONPathElement -> JSONPathElement -> Bool # (<=) :: JSONPathElement -> JSONPathElement -> Bool # (>) :: JSONPathElement -> JSONPathElement -> Bool # (>=) :: JSONPathElement -> JSONPathElement -> Bool # max :: JSONPathElement -> JSONPathElement -> JSONPathElement # min :: JSONPathElement -> JSONPathElement -> JSONPathElement # | |
| Ord Value | The ordering is total, consistent with Since: aeson-1.5.2.0 |
| Ord DotNetTime | |
Defined in Data.Aeson.Types.Internal Methods compare :: DotNetTime -> DotNetTime -> Ordering # (<) :: DotNetTime -> DotNetTime -> Bool # (<=) :: DotNetTime -> DotNetTime -> Bool # (>) :: DotNetTime -> DotNetTime -> Bool # (>=) :: DotNetTime -> DotNetTime -> Bool # max :: DotNetTime -> DotNetTime -> DotNetTime # min :: DotNetTime -> DotNetTime -> DotNetTime # | |
| Ord Pos | |
| Ord Void | Since: base-4.8.0.0 |
| Ord Version | Since: base-2.1 |
| 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 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 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 IntSet | |
| Ord BigNat | |
| Ord Stmt | |
| Ord ModName | |
Defined in Language.Haskell.TH.Syntax | |
| Ord Phases | |
| Ord RuleBndr | |
Defined in Language.Haskell.TH.Syntax | |
| Ord Pragma | |
| 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 TySynEqn | |
Defined in Language.Haskell.TH.Syntax | |
| Ord Fixity | |
| Ord Info | |
| Ord Con | |
| Ord TyVarBndr | |
| Ord ByteArray | Non-lexicographic ordering. This compares the lengths of the byte arrays first and uses a lexicographic ordering if the lengths are equal. Subject to change between major versions. Since: primitive-0.6.3.0 |
| 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 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 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 Bytes | |
| Ord Body | |
| Ord Guard | |
| Ord Range | |
| 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 Foreign | |
Defined in Language.Haskell.TH.Syntax | |
| Ord Callconv | |
Defined in Language.Haskell.TH.Syntax | |
| Ord Safety | |
| Ord Inline | |
| Ord RuleMatch | |
| 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 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 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 DatatypeVariant | |
Defined in Language.Haskell.TH.Datatype Methods compare :: DatatypeVariant -> DatatypeVariant -> Ordering # (<) :: DatatypeVariant -> DatatypeVariant -> Bool # (<=) :: DatatypeVariant -> DatatypeVariant -> Bool # (>) :: DatatypeVariant -> DatatypeVariant -> Bool # (>=) :: DatatypeVariant -> DatatypeVariant -> Bool # max :: DatatypeVariant -> DatatypeVariant -> DatatypeVariant # min :: DatatypeVariant -> DatatypeVariant -> DatatypeVariant # | |
| Ord ConstructorVariant | |
Defined in Language.Haskell.TH.Datatype Methods compare :: ConstructorVariant -> ConstructorVariant -> Ordering # (<) :: ConstructorVariant -> ConstructorVariant -> Bool # (<=) :: ConstructorVariant -> ConstructorVariant -> Bool # (>) :: ConstructorVariant -> ConstructorVariant -> Bool # (>=) :: ConstructorVariant -> ConstructorVariant -> Bool # max :: ConstructorVariant -> ConstructorVariant -> ConstructorVariant # min :: ConstructorVariant -> ConstructorVariant -> ConstructorVariant # | |
| Ord FieldStrictness | |
Defined in Language.Haskell.TH.Datatype Methods compare :: FieldStrictness -> FieldStrictness -> Ordering # (<) :: FieldStrictness -> FieldStrictness -> Bool # (<=) :: FieldStrictness -> FieldStrictness -> Bool # (>) :: FieldStrictness -> FieldStrictness -> Bool # (>=) :: FieldStrictness -> FieldStrictness -> Bool # max :: FieldStrictness -> FieldStrictness -> FieldStrictness # min :: FieldStrictness -> FieldStrictness -> FieldStrictness # | |
| Ord Unpackedness | |
Defined in Language.Haskell.TH.Datatype Methods compare :: Unpackedness -> Unpackedness -> Ordering # (<) :: Unpackedness -> Unpackedness -> Bool # (<=) :: Unpackedness -> Unpackedness -> Bool # (>) :: Unpackedness -> Unpackedness -> Bool # (>=) :: Unpackedness -> Unpackedness -> Bool # max :: Unpackedness -> Unpackedness -> Unpackedness # min :: Unpackedness -> Unpackedness -> Unpackedness # | |
| Ord Strictness | |
Defined in Language.Haskell.TH.Datatype Methods compare :: Strictness -> Strictness -> Ordering # (<) :: Strictness -> Strictness -> Bool # (<=) :: Strictness -> Strictness -> Bool # (>) :: Strictness -> Strictness -> Bool # (>=) :: Strictness -> Strictness -> Bool # max :: Strictness -> Strictness -> Strictness # min :: Strictness -> Strictness -> Strictness # | |
| Ord Specificity | |
Defined in Language.Haskell.TH.Datatype.TyVarBndr Methods compare :: Specificity -> Specificity -> Ordering # (<) :: Specificity -> Specificity -> Bool # (<=) :: Specificity -> Specificity -> Bool # (>) :: Specificity -> Specificity -> Bool # (>=) :: Specificity -> Specificity -> Bool # max :: Specificity -> Specificity -> Specificity # min :: Specificity -> Specificity -> Specificity # | |
| Ord LocalTime | |
Defined in Data.Time.LocalTime.Internal.LocalTime | |
| Ord DiffTime | |
Defined in Data.Time.Clock.Internal.DiffTime | |
| Ord Day | |
| Ord UnpackedUUID | |
Defined in Data.UUID.Types.Internal | |
| Ord UUID | |
| Ord a => Ord [a] | |
| Ord a => Ord (Maybe a) | Since: base-2.1 |
| Integral a => Ord (Ratio a) | Since: base-2.0.1 |
| Ord p => Ord (Par1 p) | Since: base-4.7.0.0 |
| 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 (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) | |
| Ord1 f => Ord (Fix f) | |
| (Functor f, Ord1 f) => Ord (Mu f) | |
| (Functor f, Ord1 f) => Ord (Nu f) | |
| Ord a => Ord (DNonEmpty a) | |
Defined in Data.DList.DNonEmpty.Internal | |
| Ord a => Ord (DList a) | |
| Ord a => Ord (Hashed a) | |
Defined in Data.Hashable.Class | |
| (Prim a, Ord a) => Ord (Vector a) | |
Defined in Data.Vector.Primitive | |
| (Storable a, Ord a) => Ord (Vector a) | |
Defined in Data.Vector.Storable | |
| Ord a => Ord (HashSet a) | |
| Ord a => Ord (Vector a) | |
Defined in Data.Vector | |
| Ord (SomeBase t) | |
| (Ord a, Prim a) => Ord (PrimArray a) | Lexicographic ordering. Subject to change between major versions. Since: primitive-0.6.4.0 |
Defined in Data.Primitive.PrimArray | |
| Ord a => Ord (SmallArray a) | Lexicographic ordering. Subject to change between major versions. |
Defined in Data.Primitive.SmallArray Methods compare :: SmallArray a -> SmallArray a -> Ordering # (<) :: SmallArray a -> SmallArray a -> Bool # (<=) :: SmallArray a -> SmallArray a -> Bool # (>) :: SmallArray a -> SmallArray a -> Bool # (>=) :: SmallArray a -> SmallArray a -> Bool # max :: SmallArray a -> SmallArray a -> SmallArray a # min :: SmallArray a -> SmallArray a -> SmallArray a # | |
| Ord a => Ord (Array a) | Lexicographic ordering. Subject to change between major versions. |
Defined in Data.Primitive.Array | |
| Ord g => Ord (AtomicGen g) | |
Defined in System.Random.Stateful | |
| Ord g => Ord (IOGen g) | |
Defined in System.Random.Stateful | |
| Ord g => Ord (STGen g) | |
Defined in System.Random.Stateful | |
| Ord g => Ord (StateGen g) | |
Defined in System.Random.Internal | |
| Ord a => Ord (Maybe a) | |
| Ord a => Ord (Identity a) | |
| Ord t => Ord (ElField '(s, t)) | |
Defined in Data.Vinyl.Functor Methods compare :: ElField '(s, t) -> ElField '(s, t) -> Ordering # (<) :: ElField '(s, t) -> ElField '(s, t) -> Bool # (<=) :: ElField '(s, t) -> ElField '(s, t) -> Bool # (>) :: ElField '(s, t) -> ElField '(s, t) -> Bool # (>=) :: ElField '(s, t) -> ElField '(s, t) -> Bool # max :: ElField '(s, t) -> ElField '(s, t) -> ElField '(s, t) # min :: ElField '(s, t) -> ElField '(s, t) -> ElField '(s, t) # | |
| (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 a, Ord b) => Ord (a, b) | |
| (Ord k, Ord v) => Ord (HashMap k v) | The ordering is total and consistent with the |
Defined in Data.HashMap.Internal | |
| (Ord k, Ord v) => Ord (Map k v) | |
| Ord a => Ord (Arg a b) | Since: base-4.9.0.0 |
| Ord a => Ord (s :-> a) | |
Defined in Composite.Record | |
| (Ord1 f, Ord a) => Ord (Cofree f a) | |
Defined in Control.Comonad.Cofree | |
| (Ord1 f, Ord a) => Ord (Free f a) | |
Defined in Control.Monad.Free | |
| (Ord1 f, Ord a) => Ord (Yoneda f a) | |
Defined in Data.Functor.Yoneda | |
| Ord (Path b t) | String ordering. The following property holds: show x `compare` show y ≡ x `compare` y |
Defined in Path.Internal.Posix | |
| (Ord a, Ord b) => Ord (Pair a b) | |
Defined in Data.Strict.Tuple | |
| (Ord a, Ord b) => Ord (These a b) | |
| (Ord a, Ord b) => Ord (Either a b) | |
| (Ord a, Ord b) => Ord (These a b) | |
| 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 (p a a) => Ord (Join p a) | |
Defined in Data.Bifunctor.Join | |
| Ord (p (Fix p a) a) => Ord (Fix p a) | |
| Ord (Rec f ('[] :: [u])) | |
| (Ord (f r), Ord (Rec f rs)) => Ord (Rec f (r ': rs)) | |
Defined in Data.Vinyl.Core Methods compare :: Rec f (r ': rs) -> Rec f (r ': rs) -> Ordering # (<) :: Rec f (r ': rs) -> Rec f (r ': rs) -> Bool # (<=) :: Rec f (r ': rs) -> Rec f (r ': rs) -> Bool # (>) :: Rec f (r ': rs) -> Rec f (r ': rs) -> Bool # (>=) :: Rec f (r ': rs) -> Rec f (r ': rs) -> Bool # max :: Rec f (r ': rs) -> Rec f (r ': rs) -> Rec f (r ': rs) # min :: Rec f (r ': rs) -> Rec f (r ': rs) -> Rec f (r ': rs) # | |
| (Ord a, Ord (f b)) => Ord (FreeF f a b) | |
Defined in Control.Monad.Trans.Free | |
| (Ord1 f, Ord1 m, Ord a) => Ord (FreeT f m a) | |
Defined in Control.Monad.Trans.Free | |
| (Ord a, Ord (f b)) => Ord (CofreeF f a b) | |
Defined in Control.Comonad.Trans.Cofree Methods compare :: CofreeF f a b -> CofreeF f a b -> Ordering # (<) :: CofreeF f a b -> CofreeF f a b -> Bool # (<=) :: CofreeF f a b -> CofreeF f a b -> Bool # (>) :: CofreeF f a b -> CofreeF f a b -> Bool # (>=) :: CofreeF f a b -> CofreeF f a b -> Bool # | |
| Ord (w (CofreeF f a (CofreeT f w a))) => Ord (CofreeT f w a) | |
Defined in Control.Comonad.Trans.Cofree Methods compare :: CofreeT f w a -> CofreeT f w a -> Ordering # (<) :: CofreeT f w a -> CofreeT f w a -> Bool # (<=) :: CofreeT f w a -> CofreeT f w a -> Bool # (>) :: CofreeT f w a -> CofreeT f w a -> Bool # (>=) :: CofreeT f w a -> CofreeT f w a -> Bool # | |
| (Ord e, Ord1 m, Ord a) => Ord (ErrorT e m a) | |
Defined in Control.Monad.Trans.Error | |
| Ord b => Ord (Tagged s b) | |
| (Ord1 f, Ord1 g, Ord a) => Ord (These1 f g a) | |
Defined in Data.Functor.These | |
| (RPureConstrained (IndexableField rs) rs, RecApplicative rs, Ord (Rec f rs)) => Ord (ARec f rs) | |
| 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 (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 (p a b) => Ord (WrappedBifunctor p a b) | |
Defined in Data.Bifunctor.Wrapped Methods compare :: WrappedBifunctor p a b -> WrappedBifunctor p a b -> Ordering # (<) :: WrappedBifunctor p a b -> WrappedBifunctor p a b -> Bool # (<=) :: WrappedBifunctor p a b -> WrappedBifunctor p a b -> Bool # (>) :: WrappedBifunctor p a b -> WrappedBifunctor p a b -> Bool # (>=) :: WrappedBifunctor p a b -> WrappedBifunctor p a b -> Bool # max :: WrappedBifunctor p a b -> WrappedBifunctor p a b -> WrappedBifunctor p a b # min :: WrappedBifunctor p a b -> WrappedBifunctor p a b -> WrappedBifunctor p a b # | |
| Ord (g b) => Ord (Joker g a b) | |
Defined in Data.Bifunctor.Joker | |
| Ord (p b a) => Ord (Flip p a b) | |
Defined in Data.Bifunctor.Flip | |
| Ord (f a) => Ord (Clown f a b) | |
Defined in Data.Bifunctor.Clown | |
| (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 (p a b), Ord (q a b)) => Ord (Sum p q a b) | |
Defined in Data.Bifunctor.Sum | |
| (Ord (f a b), Ord (g a b)) => Ord (Product f g a b) | |
Defined in Data.Bifunctor.Product Methods compare :: Product f g a b -> Product f g a b -> Ordering # (<) :: Product f g a b -> Product f g a b -> Bool # (<=) :: Product f g a b -> Product f g a b -> Bool # (>) :: Product f g a b -> Product f g a b -> Bool # (>=) :: Product f g a b -> Product f g a b -> Bool # max :: Product f g a b -> Product f g a b -> Product f g a b # min :: Product f g a b -> Product f g a b -> Product f g a b # | |
| (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 (f (p a b)) => Ord (Tannen f p a b) | |
Defined in Data.Bifunctor.Tannen Methods compare :: Tannen f p a b -> Tannen f p a b -> Ordering # (<) :: Tannen f p a b -> Tannen f p a b -> Bool # (<=) :: Tannen f p a b -> Tannen f p a b -> Bool # (>) :: Tannen f p a b -> Tannen f p a b -> Bool # (>=) :: Tannen f p a b -> Tannen f p a b -> Bool # | |
| (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 (p (f a) (g b)) => Ord (Biff p f g a b) | |
Defined in Data.Bifunctor.Biff Methods compare :: Biff p f g a b -> Biff p f g a b -> Ordering # (<) :: Biff p f g a b -> Biff p f g a b -> Bool # (<=) :: Biff p f g a b -> Biff p f g a b -> Bool # (>) :: Biff p f g a b -> Biff p f g a b -> Bool # (>=) :: Biff p f g a b -> Biff p f g a b -> Bool # | |
| (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) # | |
Function Application
($) :: forall (r :: RuntimeRep) a (b :: TYPE r). (a -> b) -> a -> b infixr 0 #
Application operator. This operator is redundant, since ordinary
application (f x) means the same as (f . However, $ x)$ has
low, right-associative binding precedence, so it sometimes allows
parentheses to be omitted; for example:
f $ g $ h x = f (g (h x))
It is also useful in higher-order situations, such as ,
or map ($ 0) xs.zipWith ($) fs xs
Note that ( is levity-polymorphic in its result type, so that
$)foo where $ Truefoo :: Bool -> Int# is well-typed.
IO
A value of type is a computation which, when performed,
does some I/O before returning 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
Maybe
The Maybe type encapsulates an optional value. A value of type
either contains a value of type Maybe aa (represented as ),
or it is empty (represented as Just aNothing). Using Maybe is a good way to
deal with errors or exceptional cases without resorting to drastic
measures such as error.
The Maybe type is also a monad. It is a simple kind of error
monad, where all errors are represented by Nothing. A richer
error monad can be built using the Either type.
Instances
| Monad Maybe | Since: base-2.1 |
| Functor Maybe | Since: base-2.1 |
| MonadFail Maybe | Since: base-4.9.0.0 |
Defined in Control.Monad.Fail | |
| Applicative Maybe | Since: base-2.1 |
| Foldable Maybe | Since: base-2.1 |
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 # elem :: Eq a => a -> Maybe a -> Bool # maximum :: Ord a => Maybe a -> a # minimum :: Ord a => Maybe a -> a # | |
| Traversable Maybe | Since: base-2.1 |
| Alternative Maybe | Since: base-2.1 |
| MonadPlus Maybe | Since: base-2.1 |
| Hashable1 Maybe | |
Defined in Data.Hashable.Class | |
| Lift a => Lift (Maybe a :: Type) | |
| Eq a => Eq (Maybe a) | Since: base-2.1 |
| Ord a => Ord (Maybe a) | Since: base-2.1 |
| Read a => Read (Maybe a) | Since: base-2.1 |
| Show a => Show (Maybe a) | Since: base-2.1 |
| Generic (Maybe a) | Since: base-4.6.0.0 |
| Semigroup a => Semigroup (Maybe a) | Since: base-4.9.0.0 |
| Semigroup a => Monoid (Maybe a) | Lift a semigroup into Since 4.11.0: constraint on inner Since: base-2.1 |
| Hashable a => Hashable (Maybe a) | |
Defined in Data.Hashable.Class | |
| Ixed (Maybe a) | |
Defined in Control.Lens.At | |
| At (Maybe a) | |
| SingKind a => SingKind (Maybe a) | Since: base-4.9.0.0 |
Defined in GHC.Generics Associated Types type DemoteRep (Maybe a) | |
| Generic1 Maybe | Since: base-4.6.0.0 |
| IsoHKD Maybe (a :: Type) | |
| SingI ('Nothing :: Maybe a) | Since: base-4.9.0.0 |
Defined in GHC.Generics | |
| SingI a2 => SingI ('Just a2 :: Maybe a1) | Since: base-4.9.0.0 |
Defined in GHC.Generics | |
| type Eval (FoldMap f ('Just x) :: a2 -> Type) | |
| type Eval (FoldMap f ('Nothing :: Maybe a1) :: a2 -> Type) | |
| type Eval (Foldr f y ('Just x) :: a2 -> Type) | |
| type Eval (Foldr f y ('Nothing :: Maybe a1) :: a2 -> Type) | |
| type Rep (Maybe a) | |
Defined in GHC.Generics | |
| type MEmpty | |
Defined in Fcf.Class.Monoid | |
| type Index (Maybe a) | |
Defined in Control.Lens.At | |
| type IxValue (Maybe a) | |
Defined in Control.Lens.At | |
| type DemoteRep (Maybe a) | |
Defined in GHC.Generics | |
| data Sing (b :: Maybe a) | |
| type Rep1 Maybe | |
| type HKD Maybe (a :: Type) | |
Defined in Data.Vinyl.XRec | |
| type (a2 :: Maybe a1) <> ('Nothing :: Maybe a1) | |
Defined in Fcf.Class.Monoid | |
| type ('Nothing :: Maybe a) <> (b :: Maybe a) | |
Defined in Fcf.Class.Monoid | |
| type Eval (Init '[a2] :: Maybe [a1] -> Type) | |
| type Eval (Init ('[] :: [a]) :: Maybe [a] -> Type) | |
| type Eval (Tail (_a ': as) :: Maybe [a] -> Type) | |
| type Eval (Tail ('[] :: [a]) :: Maybe [a] -> Type) | |
| type Eval (Init (a2 ': (b ': as)) :: Maybe [a1] -> Type) | |
| type Eval (Head (a2 ': _as) :: Maybe a1 -> Type) | |
| type Eval (Head ('[] :: [a]) :: Maybe a -> Type) | |
| type Eval (Last (a2 ': (b ': as)) :: Maybe a1 -> Type) | |
| type Eval (Last '[a2] :: Maybe a1 -> Type) | |
| type Eval (Last ('[] :: [a]) :: Maybe a -> Type) | |
| type ('Just a2 :: Maybe a1) <> ('Just b :: Maybe a1) | |
| type Eval (FindIndex p (a2 ': as) :: Maybe Nat -> Type) | |
| type Eval (FindIndex _p ('[] :: [a]) :: Maybe Nat -> Type) | |
| type Eval (NumIter a s :: Maybe (k, Nat) -> Type) | |
| type Eval (Find p (a2 ': as) :: Maybe a1 -> Type) | |
| type Eval (Find _p ('[] :: [a]) :: Maybe a -> Type) | |
| type Eval (Lookup a as :: Maybe b -> Type) | |
| type Eval (Map f ('Just a3) :: Maybe a2 -> Type) | |
| type Eval (Map f ('Nothing :: Maybe a) :: Maybe b -> Type) | |
maybe :: b -> (a -> b) -> Maybe a -> b #
The maybe function takes a default value, a function, and a Maybe
value. If the Maybe value is Nothing, the function returns the
default value. Otherwise, it applies the function to the value inside
the Just and returns the result.
Examples
Basic usage:
>>>maybe False odd (Just 3)True
>>>maybe False odd NothingFalse
Read an integer from a string using readMaybe. If we succeed,
return twice the integer; that is, apply (*2) to it. If instead
we fail to parse an integer, return 0 by default:
>>>import Text.Read ( readMaybe )>>>maybe 0 (*2) (readMaybe "5")10>>>maybe 0 (*2) (readMaybe "")0
Apply show to a Maybe Int. If we have Just n, we want to show
the underlying Int n. But if we have Nothing, we return the
empty string instead of (for example) "Nothing":
>>>maybe "" show (Just 5)"5">>>maybe "" show Nothing""
Either
The Either type represents values with two possibilities: a value of
type is either Either a b or Left a.Right b
The Either type is sometimes used to represent a value which is
either correct or an error; by convention, the Left constructor is
used to hold an error value and the Right constructor is used to
hold a correct value (mnemonic: "right" also means "correct").
Examples
The type is the type of values which can be either
a Either String IntString or an Int. The Left constructor can be used only on
Strings, and the Right constructor can be used only on Ints:
>>>let s = Left "foo" :: Either String Int>>>sLeft "foo">>>let n = Right 3 :: Either String Int>>>nRight 3>>>:type ss :: Either String Int>>>:type nn :: Either String Int
The fmap from our Functor instance will ignore Left values, but
will apply the supplied function to values contained in a Right:
>>>let s = Left "foo" :: Either String Int>>>let n = Right 3 :: Either String Int>>>fmap (*2) sLeft "foo">>>fmap (*2) nRight 6
The Monad instance for Either allows us to chain together multiple
actions which may fail, and fail overall if any of the individual
steps failed. First we'll write a function that can either parse an
Int from a Char, or fail.
>>>import Data.Char ( digitToInt, isDigit )>>>:{let parseEither :: Char -> Either String Int parseEither c | isDigit c = Right (digitToInt c) | otherwise = Left "parse error">>>:}
The following should work, since both '1' and '2' can be
parsed as Ints.
>>>:{let parseMultiple :: Either String Int parseMultiple = do x <- parseEither '1' y <- parseEither '2' return (x + y)>>>:}
>>>parseMultipleRight 3
But the following should fail overall, since the first operation where
we attempt to parse 'm' as an Int will fail:
>>>:{let parseMultiple :: Either String Int parseMultiple = do x <- parseEither 'm' y <- parseEither '2' return (x + y)>>>:}
>>>parseMultipleLeft "parse error"
Instances
| Hashable2 Either | |
Defined in Data.Hashable.Class | |
| (Lift a, Lift b) => Lift (Either a b :: Type) | |
| Monad (Either e) | Since: base-4.4.0.0 |
| Functor (Either a) | Since: base-3.0 |
| Applicative (Either e) | Since: base-3.0 |
| Foldable (Either a) | Since: base-4.7.0.0 |
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] # 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 # | |
| Traversable (Either a) | Since: base-4.7.0.0 |
Defined in Data.Traversable | |
| Hashable a => Hashable1 (Either a) | |
Defined in Data.Hashable.Class | |
| Generic1 (Either a :: Type -> Type) | Since: base-4.6.0.0 |
| IsoHKD (Either a :: Type -> Type) (b :: Type) | |
| (Eq a, Eq b) => Eq (Either a b) | Since: base-2.1 |
| (Ord a, Ord b) => Ord (Either a b) | Since: base-2.1 |
| (Read a, Read b) => Read (Either a b) | Since: base-3.0 |
| (Show a, Show b) => Show (Either a b) | Since: base-3.0 |
| Generic (Either a b) | Since: base-4.6.0.0 |
| Semigroup (Either a b) | Since: base-4.9.0.0 |
| (Hashable a, Hashable b) => Hashable (Either a b) | |
Defined in Data.Hashable.Class | |
| (Functor f, Functor g) => Functor (Lift Either f g) | |
| type Eval (FoldMap f ('Right x :: Either a3 a1) :: a2 -> Type) | |
| type Eval (FoldMap f ('Left _a :: Either a3 a1) :: a2 -> Type) | |
| type Eval (Foldr f y ('Right x :: Either a3 a1) :: a2 -> Type) | |
| type Eval (Foldr f y ('Left _a :: Either a3 a1) :: a2 -> Type) | |
| type Rep1 (Either a :: Type -> Type) | |
Defined in GHC.Generics type Rep1 (Either a :: Type -> Type) = D1 ('MetaData "Either" "Data.Either" "base" 'False) (C1 ('MetaCons "Left" 'PrefixI 'False) (S1 ('MetaSel ('Nothing :: Maybe Symbol) 'NoSourceUnpackedness 'NoSourceStrictness 'DecidedLazy) (Rec0 a)) :+: C1 ('MetaCons "Right" 'PrefixI 'False) (S1 ('MetaSel ('Nothing :: Maybe Symbol) 'NoSourceUnpackedness 'NoSourceStrictness 'DecidedLazy) Par1)) | |
| type HKD (Either a :: Type -> Type) (b :: Type) | |
| type Rep (Either a b) | |
Defined in GHC.Generics type Rep (Either a b) = D1 ('MetaData "Either" "Data.Either" "base" 'False) (C1 ('MetaCons "Left" 'PrefixI 'False) (S1 ('MetaSel ('Nothing :: Maybe Symbol) 'NoSourceUnpackedness 'NoSourceStrictness 'DecidedLazy) (Rec0 a)) :+: C1 ('MetaCons "Right" 'PrefixI 'False) (S1 ('MetaSel ('Nothing :: Maybe Symbol) 'NoSourceUnpackedness 'NoSourceStrictness 'DecidedLazy) (Rec0 b))) | |
| type Eval (Map f ('Right a3 :: Either a2 a1) :: Either a2 b -> Type) | |
| type Eval (Map f ('Left x :: Either a2 a1) :: Either a2 b -> Type) | |
| type Eval (Bimap f g ('Right y :: Either a b1) :: Either a' b2 -> Type) | |
| type Eval (Bimap f g ('Left x :: Either a1 b) :: Either a2 b' -> Type) | |
either :: (a -> c) -> (b -> c) -> Either a b -> c #
Case analysis for the Either type.
If the value is , apply the first function to Left aa;
if it is , apply the second function to Right bb.
Examples
We create two values of type , one using the
Either String IntLeft constructor and another using the Right constructor. Then
we apply "either" the length function (if we have a String)
or the "times-two" function (if we have an Int):
>>>let s = Left "foo" :: Either String Int>>>let n = Right 3 :: Either String Int>>>either length (*2) s3>>>either length (*2) n6
NonEmpty
Non-empty (and non-strict) list type.
Since: base-4.9.0.0
Constructors
| a :| [a] infixr 5 |
Instances
Map
A Map from keys k to values a.
The Semigroup operation for Map is union, which prefers
values from the left operand. If m1 maps a key k to a value
a1, and m2 maps the same key to a different value a2, then
their union m1 <> m2 maps k to a1.
Instances
| Eq2 Map | Since: containers-0.5.9 |
| Ord2 Map | Since: containers-0.5.9 |
Defined in Data.Map.Internal | |
| Show2 Map | Since: containers-0.5.9 |
| Functor (Map k) | |
| Foldable (Map k) | Folds in order of increasing key. |
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 # elem :: Eq a => a -> Map k a -> Bool # maximum :: Ord a => Map k a -> a # minimum :: Ord a => Map k a -> a # | |
| Traversable (Map k) | Traverses in order of increasing key. |
| Eq k => Eq1 (Map k) | Since: containers-0.5.9 |
| Ord k => Ord1 (Map k) | Since: containers-0.5.9 |
Defined in Data.Map.Internal | |
| (Ord k, Read k) => Read1 (Map k) | Since: containers-0.5.9 |
Defined in Data.Map.Internal | |
| Show k => Show1 (Map k) | Since: containers-0.5.9 |
| Ord k => IsList (Map k v) | Since: containers-0.5.6.2 |
| (Eq k, Eq a) => Eq (Map k a) | |
| (Data k, Data a, Ord k) => Data (Map k a) | |
Defined in Data.Map.Internal Methods gfoldl :: (forall d b. Data d => c (d -> b) -> d -> c b) -> (forall g. g -> c g) -> Map k a -> c (Map k a) # gunfold :: (forall b r. Data b => c (b -> r) -> c r) -> (forall r. r -> c r) -> Constr -> c (Map k a) # toConstr :: Map k a -> Constr # dataTypeOf :: Map k a -> DataType # dataCast1 :: Typeable t => (forall d. Data d => c (t d)) -> Maybe (c (Map k a)) # dataCast2 :: Typeable t => (forall d e. (Data d, Data e) => c (t d e)) -> Maybe (c (Map k a)) # gmapT :: (forall b. Data b => b -> b) -> Map k a -> Map k a # gmapQl :: (r -> r' -> r) -> r -> (forall d. Data d => d -> r') -> Map k a -> r # gmapQr :: forall r r'. (r' -> r -> r) -> r -> (forall d. Data d => d -> r') -> Map k a -> r # gmapQ :: (forall d. Data d => d -> u) -> Map k a -> [u] # gmapQi :: Int -> (forall d. Data d => d -> u) -> Map k a -> u # gmapM :: Monad m => (forall d. Data d => d -> m d) -> Map k a -> m (Map k a) # gmapMp :: MonadPlus m => (forall d. Data d => d -> m d) -> Map k a -> m (Map k a) # gmapMo :: MonadPlus m => (forall d. Data d => d -> m d) -> Map k a -> m (Map k a) # | |
| (Ord k, Ord v) => Ord (Map k v) | |
| (Ord k, Read k, Read e) => Read (Map k e) | |
| (Show k, Show a) => Show (Map k a) | |
| Ord k => Semigroup (Map k v) | |
| Ord k => Monoid (Map k v) | |
| (NFData k, NFData a) => NFData (Map k a) | |
Defined in Data.Map.Internal | |
| Ord k => Ixed (Map k a) | |
Defined in Control.Lens.At | |
| Ord k => At (Map k a) | |
| Ord k => Wrapped (Map k a) | |
| (t ~ Map k' a', Ord k) => Rewrapped (Map k a) t | Use |
Defined in Control.Lens.Wrapped | |
| type Item (Map k v) | |
Defined in Data.Map.Internal | |
| type Index (Map k a) | |
Defined in Control.Lens.At | |
| type IxValue (Map k a) | |
Defined in Control.Lens.At | |
| type Unwrapped (Map k a) | |
Defined in Control.Lens.Wrapped | |
Tuples & Currying
const x is a unary function which evaluates to x for all inputs.
>>>const 42 "hello"42
>>>map (const 42) [0..3][42,42,42,42]
uncurry :: (a -> b -> c) -> (a, b) -> c #
uncurry converts a curried function to a function on pairs.
Examples
>>>uncurry (+) (1,2)3
>>>uncurry ($) (show, 1)"1"
>>>map (uncurry max) [(1,2), (3,4), (6,8)][2,4,8]
Foldable
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)
Methods
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 =foldrf 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
Instances
| Foldable [] | Since: base-2.1 |
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 # elem :: Eq a => a -> [a] -> Bool # maximum :: Ord a => [a] -> a # | |
| Foldable Maybe | Since: base-2.1 |
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 # elem :: Eq a => a -> Maybe a -> Bool # maximum :: Ord a => Maybe a -> a # minimum :: Ord a => Maybe a -> a # | |
| Foldable Par1 | Since: base-4.9.0.0 |
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 # elem :: Eq a => a -> Par1 a -> Bool # maximum :: Ord a => Par1 a -> a # | |
| Foldable IResult | |
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 # elem :: Eq a => a -> IResult a -> Bool # maximum :: Ord a => IResult a -> a # minimum :: Ord a => IResult a -> a # | |
| Foldable Result | |
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 # elem :: Eq a => a -> Result a -> Bool # maximum :: Ord a => Result a -> a # minimum :: Ord a => Result a -> a # | |
| Foldable Complex | Since: base-4.9.0.0 |
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 # elem :: Eq a => a -> Complex a -> Bool # maximum :: Ord a => Complex a -> a # minimum :: Ord a => Complex a -> a # | |
| Foldable Min | Since: base-4.9.0.0 |
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 # elem :: Eq a => a -> Min a -> Bool # maximum :: Ord a => Min a -> a # | |
| Foldable Max | Since: base-4.9.0.0 |
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 # elem :: Eq a => a -> Max a -> Bool # maximum :: Ord a => Max a -> a # | |
| Foldable First | Since: base-4.9.0.0 |
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 # elem :: Eq a => a -> First a -> Bool # maximum :: Ord a => First a -> a # minimum :: Ord a => First a -> a # | |
| Foldable Last | Since: base-4.9.0.0 |
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 # elem :: Eq a => a -> Last a -> Bool # maximum :: Ord a => Last a -> a # | |
| Foldable Option | Since: base-4.9.0.0 |
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 # elem :: Eq a => a -> Option a -> Bool # maximum :: Ord a => Option a -> a # minimum :: Ord a => Option a -> a # | |
| Foldable ZipList | Since: base-4.9.0.0 |
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 # elem :: Eq a => a -> ZipList a -> Bool # maximum :: Ord a => ZipList a -> a # minimum :: Ord a => ZipList a -> a # | |
| Foldable First | Since: base-4.8.0.0 |
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 # elem :: Eq a => a -> First a -> Bool # maximum :: Ord a => First a -> a # minimum :: Ord a => First a -> a # | |
| Foldable Last | Since: base-4.8.0.0 |
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 # elem :: Eq a => a -> Last a -> Bool # maximum :: Ord a => Last a -> a # | |
| Foldable Dual | Since: base-4.8.0.0 |
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 # elem :: Eq a => a -> Dual a -> Bool # maximum :: Ord a => Dual a -> a # | |
| Foldable Sum | Since: base-4.8.0.0 |
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 # elem :: Eq a => a -> Sum a -> Bool # maximum :: Ord a => Sum a -> a # | |
| Foldable Product | Since: base-4.8.0.0 |
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 # elem :: Eq a => a -> Product a -> Bool # maximum :: Ord a => Product a -> a # minimum :: Ord a => Product a -> a # | |
| 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 # | |
| Foldable NonEmpty | Since: base-4.9.0.0 |
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 # elem :: Eq a => a -> NonEmpty a -> Bool # maximum :: Ord a => NonEmpty a -> a # minimum :: Ord a => NonEmpty a -> a # | |
| Foldable IntMap | Folds in order of increasing key. |
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 # elem :: Eq a => a -> IntMap a -> Bool # maximum :: Ord a => IntMap a -> a # minimum :: Ord a => IntMap a -> a # | |
| Foldable Tree | |
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 # elem :: Eq a => a -> Tree a -> Bool # maximum :: Ord a => Tree a -> a # | |
| Foldable Seq | |
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 # elem :: Eq a => a -> Seq a -> Bool # maximum :: Ord a => Seq a -> a # | |
| Foldable FingerTree | |
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 | |
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 # elem :: Eq a => a -> Digit a -> Bool # maximum :: Ord a => Digit a -> a # minimum :: Ord a => Digit a -> a # | |
| Foldable Node | |
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 # elem :: Eq a => a -> Node a -> Bool # maximum :: Ord a => Node a -> a # | |
| Foldable Elem | |
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 # elem :: Eq a => a -> Elem a -> Bool # maximum :: Ord a => Elem a -> a # | |
| Foldable ViewL | |
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 # elem :: Eq a => a -> ViewL a -> Bool # maximum :: Ord a => ViewL a -> a # minimum :: Ord a => ViewL a -> a # | |
| Foldable ViewR | |
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 # elem :: Eq a => a -> ViewR a -> Bool # maximum :: Ord a => ViewR a -> a # minimum :: Ord a => ViewR a -> a # | |
| Foldable Set | Folds in order of increasing key. |
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 # elem :: Eq a => a -> Set a -> Bool # maximum :: Ord a => Set a -> a # | |
| Foldable DNonEmpty | |
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] # length :: DNonEmpty a -> Int # elem :: Eq a => a -> DNonEmpty a -> Bool # maximum :: Ord a => DNonEmpty a -> a # minimum :: Ord a => DNonEmpty a -> a # | |
| Foldable DList | |
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 # elem :: Eq a => a -> DList a -> Bool # maximum :: Ord a => DList a -> a # minimum :: Ord a => DList a -> a # | |
| Foldable Hashed | |
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 # elem :: Eq a => a -> Hashed a -> Bool # maximum :: Ord a => Hashed a -> a # minimum :: Ord a => Hashed a -> a # | |
| Foldable HashSet | |
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 # elem :: Eq a => a -> HashSet a -> Bool # maximum :: Ord a => HashSet a -> a # minimum :: Ord a => HashSet a -> a # | |
| Foldable Vector | |
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 # elem :: Eq a => a -> Vector a -> Bool # maximum :: Ord a => Vector a -> a # minimum :: Ord a => Vector a -> a # | |
| Foldable SmallArray | |
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 | |
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 # elem :: Eq a => a -> Array a -> Bool # maximum :: Ord a => Array a -> a # minimum :: Ord a => Array a -> a # | |
| Foldable Maybe | |
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 # elem :: Eq a => a -> Maybe a -> Bool # maximum :: Ord a => Maybe a -> a # minimum :: Ord a => Maybe a -> a # | |
| Foldable Identity | |
Defined in Data.Vinyl.Functor 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 # elem :: Eq a => a -> Identity a -> Bool # maximum :: Ord a => Identity a -> a # minimum :: Ord a => Identity a -> a # | |
| Foldable Thunk | |
Defined in Data.Vinyl.Functor Methods fold :: Monoid m => Thunk m -> m # foldMap :: Monoid m => (a -> m) -> Thunk a -> m # foldMap' :: Monoid m => (a -> m) -> Thunk a -> m # foldr :: (a -> b -> b) -> b -> Thunk a -> b # foldr' :: (a -> b -> b) -> b -> Thunk a -> b # foldl :: (b -> a -> b) -> b -> Thunk a -> b # foldl' :: (b -> a -> b) -> b -> Thunk a -> b # foldr1 :: (a -> a -> a) -> Thunk a -> a # foldl1 :: (a -> a -> a) -> Thunk a -> a # elem :: Eq a => a -> Thunk a -> Bool # maximum :: Ord a => Thunk a -> a # minimum :: Ord a => Thunk a -> a # | |
| Foldable (Either a) | Since: base-4.7.0.0 |
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] # 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 # | |
| Foldable (V1 :: Type -> Type) | Since: base-4.9.0.0 |
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 # elem :: Eq a => a -> V1 a -> Bool # maximum :: Ord a => V1 a -> a # | |
| Foldable (U1 :: Type -> Type) | Since: base-4.9.0.0 |
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 # elem :: Eq a => a -> U1 a -> Bool # maximum :: Ord a => U1 a -> a # | |
| Foldable (UAddr :: Type -> Type) | Since: base-4.9.0.0 |
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 # elem :: Eq a => a -> UAddr a -> Bool # maximum :: Ord a => UAddr a -> a # minimum :: Ord a => UAddr a -> a # | |
| Foldable (UChar :: Type -> Type) | Since: base-4.9.0.0 |
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 # elem :: Eq a => a -> UChar a -> Bool # maximum :: Ord a => UChar a -> a # minimum :: Ord a => UChar a -> a # | |
| Foldable (UDouble :: Type -> Type) | Since: base-4.9.0.0 |
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 # elem :: Eq a => a -> UDouble a -> Bool # maximum :: Ord a => UDouble a -> a # minimum :: Ord a => UDouble a -> a # | |
| Foldable (UFloat :: Type -> Type) | Since: base-4.9.0.0 |
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 # elem :: Eq a => a -> UFloat a -> Bool # maximum :: Ord a => UFloat a -> a # minimum :: Ord a => UFloat a -> a # | |
| Foldable (UInt :: Type -> Type) | Since: base-4.9.0.0 |
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 # elem :: Eq a => a -> UInt a -> Bool # maximum :: Ord a => UInt a -> a # | |
| Foldable (UWord :: Type -> Type) | Since: base-4.9.0.0 |
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 # elem :: Eq a => a -> UWord a -> Bool # maximum :: Ord a => UWord a -> a # minimum :: Ord a => UWord a -> a # | |
| Foldable ((,) a) | Since: base-4.7.0.0 |
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 # elem :: Eq a0 => a0 -> (a, a0) -> Bool # maximum :: Ord a0 => (a, a0) -> a0 # minimum :: Ord a0 => (a, a0) -> a0 # | |
| Foldable (HashMap k) | |
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] # 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 # | |
| Foldable (Map k) | Folds in order of increasing key. |
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 # elem :: Eq a => a -> Map k a -> Bool # maximum :: Ord a => Map k a -> a # minimum :: Ord a => Map k a -> a # | |
| Foldable (Array i) | Since: base-4.8.0.0 |
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 # elem :: Eq a => a -> Array i a -> Bool # maximum :: Ord a => Array i a -> a # minimum :: Ord a => Array i a -> a # | |
| Foldable (Arg a) | Since: base-4.9.0.0 |
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 # elem :: Eq a0 => a0 -> Arg a a0 -> Bool # maximum :: Ord a0 => Arg a a0 -> a0 # minimum :: Ord a0 => Arg a a0 -> a0 # | |
| 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 # | |
| Foldable ((:->) s) | |
Defined in Composite.Record Methods fold :: Monoid m => (s :-> m) -> m # foldMap :: Monoid m => (a -> m) -> (s :-> a) -> m # foldMap' :: Monoid m => (a -> m) -> (s :-> a) -> m # foldr :: (a -> b -> b) -> b -> (s :-> a) -> b # foldr' :: (a -> b -> b) -> b -> (s :-> a) -> b # foldl :: (b -> a -> b) -> b -> (s :-> a) -> b # foldl' :: (b -> a -> b) -> b -> (s :-> a) -> b # foldr1 :: (a -> a -> a) -> (s :-> a) -> a # foldl1 :: (a -> a -> a) -> (s :-> a) -> a # elem :: Eq a => a -> (s :-> a) -> Bool # maximum :: Ord a => (s :-> a) -> a # minimum :: Ord a => (s :-> a) -> a # | |
| Foldable f => Foldable (Cofree f) | |
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 # elem :: Eq a => a -> Cofree f a -> Bool # maximum :: Ord a => Cofree f a -> a # minimum :: Ord a => Cofree f a -> a # | |
| Foldable f => Foldable (Free f) | |
Defined in Control.Monad.Free Methods fold :: Monoid m => Free f m -> m # foldMap :: Monoid m => (a -> m) -> Free f a -> m # foldMap' :: Monoid m => (a -> m) -> Free f a -> m # foldr :: (a -> b -> b) -> b -> Free f a -> b # foldr' :: (a -> b -> b) -> b -> Free f a -> b # foldl :: (b -> a -> b) -> b -> Free f a -> b # foldl' :: (b -> a -> b) -> b -> Free f a -> b # foldr1 :: (a -> a -> a) -> Free f a -> a # foldl1 :: (a -> a -> a) -> Free f a -> a # elem :: Eq a => a -> Free f a -> Bool # maximum :: Ord a => Free f a -> a # minimum :: Ord a => Free f a -> a # | |
| Foldable f => Foldable (Yoneda f) | |
Defined in Data.Functor.Yoneda Methods fold :: Monoid m => Yoneda f m -> m # foldMap :: Monoid m => (a -> m) -> Yoneda f a -> m # foldMap' :: Monoid m => (a -> m) -> Yoneda f a -> m # foldr :: (a -> b -> b) -> b -> Yoneda f a -> b # foldr' :: (a -> b -> b) -> b -> Yoneda f a -> b # foldl :: (b -> a -> b) -> b -> Yoneda f a -> b # foldl' :: (b -> a -> b) -> b -> Yoneda f a -> b # foldr1 :: (a -> a -> a) -> Yoneda f a -> a # foldl1 :: (a -> a -> a) -> Yoneda f a -> a # elem :: Eq a => a -> Yoneda f a -> Bool # maximum :: Ord a => Yoneda f a -> a # minimum :: Ord a => Yoneda f a -> a # | |
| Foldable (Pair e) | |
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 # elem :: Eq a => a -> Pair e a -> Bool # maximum :: Ord a => Pair e a -> a # minimum :: Ord a => Pair e a -> a # | |
| Foldable (These a) | |
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] # elem :: Eq a0 => a0 -> These a a0 -> Bool # maximum :: Ord a0 => These a a0 -> a0 # minimum :: Ord a0 => These a a0 -> a0 # | |
| Foldable (Either e) | |
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 # elem :: Eq a => a -> Either e a -> Bool # maximum :: Ord a => Either e a -> a # minimum :: Ord a => Either e a -> a # | |
| Foldable (These a) | |
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] # elem :: Eq a0 => a0 -> These a a0 -> Bool # maximum :: Ord a0 => These a a0 -> a0 # minimum :: Ord a0 => These a a0 -> a0 # | |
| Foldable f => Foldable (Rec1 f) | Since: base-4.9.0.0 |
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 # elem :: Eq a => a -> Rec1 f a -> Bool # maximum :: Ord a => Rec1 f a -> a # minimum :: Ord a => Rec1 f a -> a # | |
| Foldable f => Foldable (Ap f) | Since: base-4.12.0.0 |
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 # elem :: Eq a => a -> Ap f a -> Bool # maximum :: Ord a => Ap f a -> a # | |
| Foldable f => Foldable (Alt f) | Since: base-4.12.0.0 |
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 # elem :: Eq a => a -> Alt f a -> Bool # maximum :: Ord a => Alt f a -> a # minimum :: Ord a => Alt f a -> a # | |
| Bifoldable p => Foldable (Join p) | |
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 # elem :: Eq a => a -> Join p a -> Bool # maximum :: Ord a => Join p a -> a # minimum :: Ord a => Join p a -> a # | |
| Bifoldable p => Foldable (Fix p) | |
Defined in Data.Bifunctor.Fix Methods fold :: Monoid m => Fix p m -> m # foldMap :: Monoid m => (a -> m) -> Fix p a -> m # foldMap' :: Monoid m => (a -> m) -> Fix p a -> m # foldr :: (a -> b -> b) -> b -> Fix p a -> b # foldr' :: (a -> b -> b) -> b -> Fix p a -> b # foldl :: (b -> a -> b) -> b -> Fix p a -> b # foldl' :: (b -> a -> b) -> b -> Fix p a -> b # foldr1 :: (a -> a -> a) -> Fix p a -> a # foldl1 :: (a -> a -> a) -> Fix p a -> a # elem :: Eq a => a -> Fix p a -> Bool # maximum :: Ord a => Fix p a -> a # minimum :: Ord a => Fix p a -> a # | |
| Foldable w => Foldable (EnvT e w) | |
Defined in Control.Comonad.Trans.Env Methods fold :: Monoid m => EnvT e w m -> m # foldMap :: Monoid m => (a -> m) -> EnvT e w a -> m # foldMap' :: Monoid m => (a -> m) -> EnvT e w a -> m # foldr :: (a -> b -> b) -> b -> EnvT e w a -> b # foldr' :: (a -> b -> b) -> b -> EnvT e w a -> b # foldl :: (b -> a -> b) -> b -> EnvT e w a -> b # foldl' :: (b -> a -> b) -> b -> EnvT e w a -> b # foldr1 :: (a -> a -> a) -> EnvT e w a -> a # foldl1 :: (a -> a -> a) -> EnvT e w a -> a # elem :: Eq a => a -> EnvT e w a -> Bool # maximum :: Ord a => EnvT e w a -> a # minimum :: Ord a => EnvT e w a -> a # | |
| Foldable (Const a :: Type -> Type) | |
Defined in Data.Vinyl.Functor Methods fold :: Monoid m => Const a m -> m # foldMap :: Monoid m => (a0 -> m) -> Const a a0 -> m # foldMap' :: Monoid m => (a0 -> m) -> Const a a0 -> m # foldr :: (a0 -> b -> b) -> b -> Const a a0 -> b # foldr' :: (a0 -> b -> b) -> b -> Const a a0 -> b # foldl :: (b -> a0 -> b) -> b -> Const a a0 -> b # foldl' :: (b -> a0 -> b) -> b -> Const a a0 -> b # foldr1 :: (a0 -> a0 -> a0) -> Const a a0 -> a0 # foldl1 :: (a0 -> a0 -> a0) -> Const a a0 -> a0 # toList :: Const a a0 -> [a0] # elem :: Eq a0 => a0 -> Const a a0 -> Bool # maximum :: Ord a0 => Const a a0 -> a0 # minimum :: Ord a0 => Const a a0 -> a0 # | |
| Foldable f => Foldable (FreeF f a) | |
Defined in Control.Monad.Trans.Free Methods fold :: Monoid m => FreeF f a m -> m # foldMap :: Monoid m => (a0 -> m) -> FreeF f a a0 -> m # foldMap' :: Monoid m => (a0 -> m) -> FreeF f a a0 -> m # foldr :: (a0 -> b -> b) -> b -> FreeF f a a0 -> b # foldr' :: (a0 -> b -> b) -> b -> FreeF f a a0 -> b # foldl :: (b -> a0 -> b) -> b -> FreeF f a a0 -> b # foldl' :: (b -> a0 -> b) -> b -> FreeF f a a0 -> b # foldr1 :: (a0 -> a0 -> a0) -> FreeF f a a0 -> a0 # foldl1 :: (a0 -> a0 -> a0) -> FreeF f a a0 -> a0 # toList :: FreeF f a a0 -> [a0] # null :: FreeF f a a0 -> Bool # length :: FreeF f a a0 -> Int # elem :: Eq a0 => a0 -> FreeF f a a0 -> Bool # maximum :: Ord a0 => FreeF f a a0 -> a0 # minimum :: Ord a0 => FreeF f a a0 -> a0 # | |
| (Foldable m, Foldable f) => Foldable (FreeT f m) | |
Defined in Control.Monad.Trans.Free Methods fold :: Monoid m0 => FreeT f m m0 -> m0 # foldMap :: Monoid m0 => (a -> m0) -> FreeT f m a -> m0 # foldMap' :: Monoid m0 => (a -> m0) -> FreeT f m a -> m0 # foldr :: (a -> b -> b) -> b -> FreeT f m a -> b # foldr' :: (a -> b -> b) -> b -> FreeT f m a -> b # foldl :: (b -> a -> b) -> b -> FreeT f m a -> b # foldl' :: (b -> a -> b) -> b -> FreeT f m a -> b # foldr1 :: (a -> a -> a) -> FreeT f m a -> a # foldl1 :: (a -> a -> a) -> FreeT f m a -> a # toList :: FreeT f m a -> [a] # length :: FreeT f m a -> Int # elem :: Eq a => a -> FreeT f m a -> Bool # maximum :: Ord a => FreeT f m a -> a # minimum :: Ord a => FreeT f m a -> a # | |
| Foldable f => Foldable (CofreeF f a) | |
Defined in Control.Comonad.Trans.Cofree Methods fold :: Monoid m => CofreeF f a m -> m # foldMap :: Monoid m => (a0 -> m) -> CofreeF f a a0 -> m # foldMap' :: Monoid m => (a0 -> m) -> CofreeF f a a0 -> m # foldr :: (a0 -> b -> b) -> b -> CofreeF f a a0 -> b # foldr' :: (a0 -> b -> b) -> b -> CofreeF f a a0 -> b # foldl :: (b -> a0 -> b) -> b -> CofreeF f a a0 -> b # foldl' :: (b -> a0 -> b) -> b -> CofreeF f a a0 -> b # foldr1 :: (a0 -> a0 -> a0) -> CofreeF f a a0 -> a0 # foldl1 :: (a0 -> a0 -> a0) -> CofreeF f a a0 -> a0 # toList :: CofreeF f a a0 -> [a0] # null :: CofreeF f a a0 -> Bool # length :: CofreeF f a a0 -> Int # elem :: Eq a0 => a0 -> CofreeF f a a0 -> Bool # maximum :: Ord a0 => CofreeF f a a0 -> a0 # minimum :: Ord a0 => CofreeF f a a0 -> a0 # | |
| (Foldable f, Foldable w) => Foldable (CofreeT f w) | |
Defined in Control.Comonad.Trans.Cofree Methods fold :: Monoid m => CofreeT f w m -> m # foldMap :: Monoid m => (a -> m) -> CofreeT f w a -> m # foldMap' :: Monoid m => (a -> m) -> CofreeT f w a -> m # foldr :: (a -> b -> b) -> b -> CofreeT f w a -> b # foldr' :: (a -> b -> b) -> b -> CofreeT f w a -> b # foldl :: (b -> a -> b) -> b -> CofreeT f w a -> b # foldl' :: (b -> a -> b) -> b -> CofreeT f w a -> b # foldr1 :: (a -> a -> a) -> CofreeT f w a -> a # foldl1 :: (a -> a -> a) -> CofreeT f w a -> a # toList :: CofreeT f w a -> [a] # null :: CofreeT f w a -> Bool # length :: CofreeT f w a -> Int # elem :: Eq a => a -> CofreeT f w a -> Bool # maximum :: Ord a => CofreeT f w a -> a # minimum :: Ord a => CofreeT f w a -> a # | |
| Foldable f => Foldable (ErrorT e f) | |
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 # | |
| Foldable (Tagged s) | |
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 # elem :: Eq a => a -> Tagged s a -> Bool # maximum :: Ord a => Tagged s a -> a # minimum :: Ord a => Tagged s a -> a # | |
| (Foldable f, Foldable g) => Foldable (These1 f g) | |
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 # | |
| Foldable (K1 i c :: Type -> Type) | Since: base-4.9.0.0 |
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 # 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 # | |
| (Foldable f, Foldable g) => Foldable (f :+: g) | Since: base-4.9.0.0 |
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] # 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 # | |
| (Foldable f, Foldable g) => Foldable (f :*: g) | Since: base-4.9.0.0 |
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] # 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 # | |
| (Foldable f, Foldable g) => Foldable (Product f g) | Since: base-4.9.0.0 |
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 # | |
| (Foldable f, Foldable g) => Foldable (Sum f g) | Since: base-4.9.0.0 |
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 # 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 # | |
| Foldable f => Foldable (M1 i c f) | Since: base-4.9.0.0 |
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 # 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 # | |
| (Foldable f, Foldable g) => Foldable (f :.: g) | Since: base-4.9.0.0 |
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] # 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 # | |
| (Foldable f, Foldable g) => Foldable (Compose f g) | Since: base-4.9.0.0 |
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 # | |
| Bifoldable p => Foldable (WrappedBifunctor p a) | |
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) | |
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 # | |
| Bifoldable p => Foldable (Flip p a) | |
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] # 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 # | |
| Foldable (Clown f a :: Type -> Type) | |
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 # | |
| (Foldable f, Foldable g) => Foldable (Compose f g) | |
Defined in Data.Vinyl.Functor 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 # | |
| (Foldable f, Bifoldable p) => Foldable (Tannen f p a) | |
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 # | |
| (Bifoldable p, Foldable g) => Foldable (Biff p f g a) | |
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 # | |
Functor
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:
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
Methods
fmap :: (a -> b) -> f a -> f b #
Using ApplicativeDo: '' can be understood as
the fmap f asdo expression
do a <- as pure (f a)
with an inferred Functor constraint.
Instances
($>) :: Functor f => f a -> b -> f b infixl 4 #
Flipped version of <$.
Using ApplicativeDo: 'as ' can be understood as the
$> bdo expression
do as pure b
with an inferred Functor constraint.
Examples
Replace the contents of a with a constant
Maybe IntString:
>>>Nothing $> "foo"Nothing>>>Just 90210 $> "foo"Just "foo"
Replace the contents of an
with a constant Either Int IntString, 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 => (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, <$> is function
application lifted over a Functor.
Examples
Convert from a to a Maybe Int using Maybe
Stringshow:
>>>show <$> NothingNothing>>>show <$> Just 3Just "3"
Convert from an to an
Either Int IntEither IntString using show:
>>>show <$> Left 17Left 17>>>show <$> Right 17Right "17"
Double each element of a list:
>>>(*2) <$> [1,2,3][2,4,6]
Apply even to the second element of a pair:
>>>even <$> (2,2)(2,True)
void :: Functor f => f a -> f () #
discards or ignores the result of evaluation, such
as the return value of an void valueIO action.
Using ApplicativeDo: '' can be understood as the
void asdo expression
do as pure ()
with an inferred Functor constraint.
Examples
Replace the contents of a with unit:Maybe Int
>>>void NothingNothing>>>void (Just 3)Just ()
Replace the contents of an
with unit, resulting in an Either Int Int: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
Applicative
class Functor f => Applicative (f :: Type -> Type) where #
A functor with application, providing operations to
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:
(<*>) =liftA2id
liftA2f x y = f<$>x<*>y
Further, any definition must satisfy the following:
- Identity
pureid<*>v = v- Composition
pure(.)<*>u<*>v<*>w = u<*>(v<*>w)- Homomorphism
puref<*>purex =pure(f x)- Interchange
u
<*>purey =pure($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
liftA2p (liftA2q u v) =liftA2f u .liftA2g v
If f is also a Monad, it should satisfy
(which implies that pure and <*> satisfy the applicative functor laws).
Methods
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 ' can be understood as
the <*> asdo 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: '' can be understood
as the liftA2 f as bsdo expression
do a <- as b <- bs pure (f a b)
Instances
| Applicative [] | Since: base-2.1 |
| Applicative Maybe | Since: base-2.1 |
| Applicative IO | Since: base-2.1 |
| Applicative Par1 | Since: base-4.9.0.0 |
| Applicative Q | |
| Applicative IResult | |
| Applicative Result | |
| Applicative Parser | |
| Applicative Complex | Since: base-4.9.0.0 |
| Applicative Min | Since: base-4.9.0.0 |
| Applicative Max | Since: base-4.9.0.0 |
| Applicative First | Since: base-4.9.0.0 |
| Applicative Last | Since: base-4.9.0.0 |
| Applicative Option | Since: base-4.9.0.0 |
| Applicative ZipList | f <$> ZipList xs1 <*> ... <*> ZipList xsN
= ZipList (zipWithN f xs1 ... xsN)where (\a b c -> stimes c [a, b]) <$> 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 |
| Applicative ReadP | Since: base-4.6.0.0 |
| Applicative NonEmpty | Since: base-4.9.0.0 |
| Applicative Tree | |
| Applicative Seq | Since: containers-0.5.4 |
| Applicative DNonEmpty | |
Defined in Data.DList.DNonEmpty.Internal | |
| Applicative DList | |
| Applicative Vector | |
| Applicative SmallArray | |
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 | |
| Applicative Identity | |
| Applicative Thunk | |
| Applicative P | Since: base-4.5.0.0 |
| Applicative (Either e) | Since: base-3.0 |
| Applicative (U1 :: Type -> Type) | Since: base-4.9.0.0 |
| Monoid a => Applicative ((,) a) | For tuples, the ("hello ", (+15)) <*> ("world!", 2002)
("hello world!",2017)Since: base-2.1 |
| Representable f => Applicative (Co f) | |
| Applicative (Parser i) | |
| Monad m => Applicative (WrappedMonad m) | Since: base-2.1 |
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 |
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 ((:->) s) | |
| Alternative f => Applicative (Cofree f) | |
| Functor f => Applicative (Free f) | |
| Applicative f => Applicative (Yoneda f) | |
| Applicative (ReifiedGetter s) | |
Defined in Control.Lens.Reified Methods pure :: a -> ReifiedGetter s a # (<*>) :: ReifiedGetter s (a -> b) -> ReifiedGetter s a -> ReifiedGetter s b # liftA2 :: (a -> b -> c) -> ReifiedGetter s a -> ReifiedGetter s b -> ReifiedGetter s c # (*>) :: ReifiedGetter s a -> ReifiedGetter s b -> ReifiedGetter s b # (<*) :: ReifiedGetter s a -> ReifiedGetter s b -> ReifiedGetter s a # | |
| Applicative (ReifiedFold s) | |
Defined in Control.Lens.Reified Methods pure :: a -> ReifiedFold s a # (<*>) :: ReifiedFold s (a -> b) -> ReifiedFold s a -> ReifiedFold s b # liftA2 :: (a -> b -> c) -> ReifiedFold s a -> ReifiedFold s b -> ReifiedFold s c # (*>) :: ReifiedFold s a -> ReifiedFold s b -> ReifiedFold s b # (<*) :: ReifiedFold s a -> ReifiedFold s b -> ReifiedFold s a # | |
| Applicative f => Applicative (Indexing f) | |
Defined in Control.Lens.Internal.Indexed | |
| Applicative f => Applicative (Indexing64 f) | |
Defined in Control.Lens.Internal.Indexed Methods pure :: a -> Indexing64 f a # (<*>) :: Indexing64 f (a -> b) -> Indexing64 f a -> Indexing64 f b # liftA2 :: (a -> b -> c) -> Indexing64 f a -> Indexing64 f b -> Indexing64 f c # (*>) :: Indexing64 f a -> Indexing64 f b -> Indexing64 f b # (<*) :: Indexing64 f a -> Indexing64 f b -> Indexing64 f a # | |
| (Applicative (Rep p), Representable p) => Applicative (Prep p) | |
| Semigroup a => Applicative (These a) | |
| Semigroup a => Applicative (These a) | |
| Applicative f => Applicative (Rec1 f) | Since: base-4.9.0.0 |
| (Monoid a, Monoid b) => Applicative ((,,) a b) | Since: base-4.14.0.0 |
| Arrow a => Applicative (WrappedArrow a b) | Since: base-2.1 |
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 |
Defined in Control.Arrow | |
| Biapplicative p => Applicative (Join p) | |
| Biapplicative p => Applicative (Fix p) | |
| (Monoid e, Applicative m) => Applicative (EnvT e m) | |
| (Applicative f, Monad f) => Applicative (WhenMissing f x) | Equivalent to Since: containers-0.5.9 |
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 f, Monad m) => Applicative (FreeT f m) | |
Defined in Control.Monad.Trans.Free | |
| (Alternative f, Applicative w) => Applicative (CofreeT f w) | |
Defined in Control.Comonad.Trans.Cofree | |
| (Applicative f, Applicative g) => Applicative (Day f g) | |
| (Functor m, Monad m) => Applicative (ErrorT e m) | |
Defined in Control.Monad.Trans.Error | |
| Applicative (Tagged s) | |
| Applicative (Indexed i a) | |
Defined in Control.Lens.Internal.Indexed | |
| (Profunctor p, Arrow p) => Applicative (Tambara p a) | |
Defined in Data.Profunctor.Strong | |
| Applicative ((->) r :: Type -> Type) | Since: base-2.1 |
| Monoid c => Applicative (K1 i c :: Type -> Type) | Since: base-4.12.0.0 |
| (Applicative f, Applicative g) => Applicative (f :*: g) | Since: base-4.9.0.0 |
| (Monoid a, Monoid b, Monoid c) => Applicative ((,,,) a b c) | Since: base-4.14.0.0 |
Defined in GHC.Base | |
| (Applicative f, Applicative g) => Applicative (Product f g) | Since: base-4.9.0.0 |
Defined in Data.Functor.Product | |
| Applicative (Cokleisli w a) | |
Defined in Control.Comonad Methods pure :: a0 -> Cokleisli w a a0 # (<*>) :: Cokleisli w a (a0 -> b) -> Cokleisli w a a0 -> Cokleisli w a b # liftA2 :: (a0 -> b -> c) -> Cokleisli w a a0 -> Cokleisli w a b -> Cokleisli w a c # (*>) :: Cokleisli w a a0 -> Cokleisli w a b -> Cokleisli w a b # (<*) :: Cokleisli w a a0 -> Cokleisli w a b -> Cokleisli w a a0 # | |
| (Monad f, Applicative f) => Applicative (WhenMatched f x y) | Equivalent to Since: containers-0.5.9 |
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 Since: containers-0.5.9 |
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 |
| (Applicative f, Applicative g) => Applicative (f :.: g) | Since: base-4.9.0.0 |
| (Applicative f, Applicative g) => Applicative (Compose f g) | Since: base-4.9.0.0 |
Defined in Data.Functor.Compose | |
| (Monad f, Applicative f) => Applicative (WhenMatched f k x y) | Equivalent to Since: containers-0.5.9 |
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 # | |
| Reifies s (ReifiedApplicative f) => Applicative (ReflectedApplicative f s) | |
Defined in Data.Reflection Methods pure :: a -> ReflectedApplicative f s a # (<*>) :: ReflectedApplicative f s (a -> b) -> ReflectedApplicative f s a -> ReflectedApplicative f s b # liftA2 :: (a -> b -> c) -> ReflectedApplicative f s a -> ReflectedApplicative f s b -> ReflectedApplicative f s c # (*>) :: ReflectedApplicative f s a -> ReflectedApplicative f s b -> ReflectedApplicative f s b # (<*) :: ReflectedApplicative f s a -> ReflectedApplicative f s b -> ReflectedApplicative f s a # | |
| (Applicative f, Applicative g) => Applicative (Compose f g) | |
Defined in Data.Vinyl.Functor | |
| (Applicative f, Applicative g) => Applicative (Lift (,) f g) | |
Defined in Data.Vinyl.Functor | |
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.
unless :: Applicative f => Bool -> f () -> f () #
The reverse of when.
whenJust :: Applicative m => Maybe a -> (a -> m ()) -> m () #
Traversable
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 .for every applicative transformationtraversef =traverse(t . f)t- Identity
traverseIdentity=Identity- Composition
traverse(Compose.fmapg . f) =Compose.fmap(traverseg) .traversef
A definition of sequenceA must satisfy the following laws:
- Naturality
t .for every applicative transformationsequenceA=sequenceA.fmaptt- Identity
sequenceA.fmapIdentity=Identity- Composition
sequenceA.fmapCompose=Compose.fmapsequenceA.sequenceA
where an applicative transformation is a function
t :: (Applicative f, Applicative g) => f a -> g a
preserving the Applicative operations, i.e.
t (purex) =purex 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
traversepure=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:
- In the
Functorinstance,fmapshould be equivalent to traversal with the identity applicative functor (fmapDefault). - In the
Foldableinstance,foldMapshould be equivalent to traversal with a constant applicative functor (foldMapDefault).
References: [1] The Essence of the Iterator Pattern, Jeremy Gibbons and Bruno C. d. S. Oliveira
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_.
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
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.
for_ :: (Foldable t, Applicative f) => t a -> (a -> f b) -> f () #
filterM :: Applicative m => (a -> m Bool) -> [a] -> m [a] #
This generalizes the list-based filter function.
Monad
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
returna>>=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 ' can be understood as the >>= bsdo 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 ' can be understood as the >> bsdo expression
do as bs
Inject a value into the monadic type.
Instances
| Monad [] | Since: base-2.1 |
| Monad Maybe | Since: base-2.1 |
| Monad IO | Since: base-2.1 |
| Monad Par1 | Since: base-4.9.0.0 |
| Monad Q | |
| Monad IResult | |
| Monad Result | |
| Monad Parser | |
| Monad Complex | Since: base-4.9.0.0 |
| Monad Min | Since: base-4.9.0.0 |
| Monad Max | Since: base-4.9.0.0 |
| Monad First | Since: base-4.9.0.0 |
| Monad Last | Since: base-4.9.0.0 |
| Monad Option | Since: base-4.9.0.0 |
| Monad ReadP | Since: base-2.1 |
| Monad NonEmpty | Since: base-4.9.0.0 |
| Monad Tree | |
| Monad Seq | |
| Monad DNonEmpty | |
| Monad DList | |
| Monad Vector | |
| Monad SmallArray | |
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 | |
| Monad Identity | |
| Monad Thunk | |
| Monad P | Since: base-2.1 |
| Monad (Either e) | Since: base-4.4.0.0 |
| Monad (U1 :: Type -> Type) | Since: base-4.9.0.0 |
| Monoid a => Monad ((,) a) | Since: base-4.9.0.0 |
| Representable f => Monad (Co f) | |
| Monad (Parser i) | |
| Monad m => Monad (WrappedMonad m) | Since: base-4.7.0.0 |
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 |
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 ((:->) s) | |
| Alternative f => Monad (Cofree f) | |
| Functor f => Monad (Free f) | |
| Monad m => Monad (Yoneda m) | |
| Monad (ReifiedGetter s) | |
Defined in Control.Lens.Reified Methods (>>=) :: ReifiedGetter s a -> (a -> ReifiedGetter s b) -> ReifiedGetter s b # (>>) :: ReifiedGetter s a -> ReifiedGetter s b -> ReifiedGetter s b # return :: a -> ReifiedGetter s a # | |
| Monad (ReifiedFold s) | |
Defined in Control.Lens.Reified Methods (>>=) :: ReifiedFold s a -> (a -> ReifiedFold s b) -> ReifiedFold s b # (>>) :: ReifiedFold s a -> ReifiedFold s b -> ReifiedFold s b # return :: a -> ReifiedFold s a # | |
| (Monad (Rep p), Representable p) => Monad (Prep p) | |
| Semigroup a => Monad (These a) | |
| Semigroup a => Monad (These a) | |
| Monad f => Monad (Rec1 f) | Since: base-4.9.0.0 |
| (Monoid a, Monoid b) => Monad ((,,) a b) | Since: base-4.14.0.0 |
| Monad m => Monad (Kleisli m a) | Since: base-4.14.0.0 |
| (Applicative f, Monad f) => Monad (WhenMissing f x) | Equivalent to Since: containers-0.5.9 |
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 # | |
| (Functor f, Monad m) => Monad (FreeT f m) | |
| (Alternative f, Monad w) => Monad (CofreeT f w) | |
| (Monad m, Error e) => Monad (ErrorT e m) | |
| Monad (Tagged s) | |
| Monad (Indexed i a) | |
| Monad ((->) r :: Type -> Type) | Since: base-2.1 |
| (Monad f, Monad g) => Monad (f :*: g) | Since: base-4.9.0.0 |
| (Monoid a, Monoid b, Monoid c) => Monad ((,,,) a b c) | Since: base-4.14.0.0 |
| (Monad f, Monad g) => Monad (Product f g) | Since: base-4.9.0.0 |
| Monad (Cokleisli w a) | |
| (Monad f, Applicative f) => Monad (WhenMatched f x y) | Equivalent to Since: containers-0.5.9 |
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 Since: containers-0.5.9 |
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 |
| (Monad f, Applicative f) => Monad (WhenMatched f k x y) | Equivalent to Since: containers-0.5.9 |
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 # | |
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.
'' can be understood as the join bssdo expression
do bs <- bss bs
Examples
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
forM :: (Traversable t, Monad m) => t a -> (a -> m b) -> m (t b) #
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.
(=<<) :: Monad m => (a -> m b) -> m a -> m b infixr 1 #
Same as >>=, but with the arguments interchanged.
(>=>) :: Monad m => (a -> m b) -> (b -> m c) -> a -> m c infixr 1 #
Left-to-right composition of Kleisli arrows.
'(bs ' can be understood as the >=> cs) ado expression
do b <- bs a cs b
Contravariant
class Contravariant (f :: Type -> Type) where #
The class of contravariant functors.
Whereas in Haskell, one can think of a Functor as containing or producing
values, a contravariant functor is a functor that can be thought of as
consuming values.
As an example, consider the type of predicate functions a -> Bool. One
such predicate might be negative x = x < 0, which
classifies integers as to whether they are negative. However, given this
predicate, we can re-use it in other situations, providing we have a way to
map values to integers. For instance, we can use the negative predicate
on a person's bank balance to work out if they are currently overdrawn:
newtype Predicate a = Predicate { getPredicate :: a -> Bool }
instance Contravariant Predicate where
contramap f (Predicate p) = Predicate (p . f)
| `- First, map the input...
`----- then apply the predicate.
overdrawn :: Predicate Person
overdrawn = contramap personBankBalance negative
Any instance should be subject to the following laws:
Note, that the second law follows from the free theorem of the type of
contramap and the first law, so you need only check that the former
condition holds.
Instances
(>$<) :: Contravariant f => (a -> b) -> f b -> f a infixl 4 #
This is an infix alias for contramap.
Instances
| Contravariant Predicate | A |
| Semigroup (Predicate a) | |
| Monoid (Predicate a) | |
| Wrapped (Predicate a) | |
| t ~ Predicate b => Rewrapped (Predicate a) t | |
Defined in Control.Lens.Wrapped | |
| type Unwrapped (Predicate a) | |
Defined in Control.Lens.Wrapped | |
data Equivalence a #
This data type represents an equivalence relation.
Equivalence relations are expected to satisfy three laws:
- Reflexivity
getEquivalencef a a = True- Symmetry
getEquivalencef a b =getEquivalencef b a- Transitivity
- If
andgetEquivalencef a bare bothgetEquivalencef b cTruethen so is.getEquivalencef a c
The types alone do not enforce these laws, so you'll have to check them yourself.
Instances
data Comparison a #
Defines a total ordering on a type as per compare.
This condition is not checked by the types. You must ensure that the supplied values are valid total orderings yourself.
Instances
Dual function arrows.
Instances
| Contravariant (Op a) | |
| Category Op | |
| Floating a => Floating (Op a b) | |
| Fractional a => Fractional (Op a b) | |
| Num a => Num (Op a b) | |
| Semigroup a => Semigroup (Op a b) | |
| Monoid a => Monoid (Op a b) | |
| Wrapped (Op a b) | |
| t ~ Op a' b' => Rewrapped (Op a b) t | |
Defined in Control.Lens.Wrapped | |
| type Unwrapped (Op a b) | |
Defined in Control.Lens.Wrapped | |
Distributive
class Functor g => Distributive (g :: Type -> Type) where #
This is the categorical dual of Traversable.
Due to the lack of non-trivial comonoids in Haskell, we can restrict
ourselves to requiring a Functor rather than
some Coapplicative class. Categorically every Distributive
functor is actually a right adjoint, and so it must be Representable
endofunctor and preserve all limits. This is a fancy way of saying it
is isomorphic to (->) x for some x.
To be distributable a container will need to have a way to consistently zip a potentially infinite number of copies of itself. This effectively means that the holes in all values of that type, must have the same cardinality, fixed sized vectors, infinite streams, functions, etc. and no extra information to try to merge together.
Minimal complete definition
Methods
distribute :: Functor f => f (g a) -> g (f a) #
The dual of sequenceA
>>>distribute [(+1),(+2)] 1[2,3]
distribute=collectiddistribute.distribute=id
Instances
Comonad
class Functor w => Comonad (w :: Type -> Type) where #
There are two ways to define a comonad:
I. Provide definitions for extract and extend
satisfying these laws:
extendextract=idextract.extendf = fextendf .extendg =extend(f .extendg)
In this case, you may simply set fmap = liftW.
These laws are directly analogous to the laws for monads and perhaps can be made clearer by viewing them as laws stating that Cokleisli composition must be associative, and has extract for a unit:
f=>=extract= fextract=>=f = f (f=>=g)=>=h = f=>=(g=>=h)
II. Alternately, you may choose to provide definitions for fmap,
extract, and duplicate satisfying these laws:
extract.duplicate=idfmapextract.duplicate=idduplicate.duplicate=fmapduplicate.duplicate
In this case you may not rely on the ability to define fmap in
terms of liftW.
You may of course, choose to define both duplicate and extend.
In that case you must also satisfy these laws:
extendf =fmapf .duplicateduplicate=extendidfmapf =extend(f .extract)
These are the default definitions of extend and duplicate and
the definition of liftW respectively.
Methods
Instances
| Comonad Identity | |
| Comonad NonEmpty | |
| Comonad Tree | |
| Comonad ((,) e) | |
| (Representable f, Monoid (Rep f)) => Comonad (Co f) | |
| Comonad (Arg e) | |
| Functor f => Comonad (Cofree f) | |
| Comonad w => Comonad (Yoneda w) | |
| Monoid s => Comonad (ReifiedGetter s) | |
Defined in Control.Lens.Reified Methods extract :: ReifiedGetter s a -> a # duplicate :: ReifiedGetter s a -> ReifiedGetter s (ReifiedGetter s a) # extend :: (ReifiedGetter s a -> b) -> ReifiedGetter s a -> ReifiedGetter s b # | |
| Comonad w => Comonad (EnvT e w) | |
| Comonad w => Comonad (IdentityT w) | |
| (Functor f, Comonad w) => Comonad (CofreeT f w) | |
| (Comonad f, Comonad g) => Comonad (Day f g) | |
| Comonad (Tagged s) | |
| Monoid m => Comonad ((->) m :: Type -> Type) | |
| (Comonad f, Comonad g) => Comonad (Sum f g) | |
(=>=) :: Comonad w => (w a -> b) -> (w b -> c) -> w a -> c infixr 1 #
Left-to-right Cokleisli composition
Profunctor
class Profunctor (p :: Type -> Type -> Type) where #
Formally, the class Profunctor represents a profunctor
from Hask -> Hask.
Intuitively it is a bifunctor where the first argument is contravariant and the second argument is covariant.
You can define a Profunctor by either defining dimap or by defining both
lmap and rmap.
If you supply dimap, you should ensure that:
dimapidid≡id
If you supply lmap and rmap, ensure:
lmapid≡idrmapid≡id
If you supply both, you should also ensure:
dimapf g ≡lmapf.rmapg
These ensure by parametricity:
dimap(f.g) (h.i) ≡dimapg h.dimapf ilmap(f.g) ≡lmapg.lmapfrmap(f.g) ≡rmapf.rmapg
Instances
| Profunctor ReifiedGetter | |
Defined in Control.Lens.Reified Methods dimap :: (a -> b) -> (c -> d) -> ReifiedGetter b c -> ReifiedGetter a d # lmap :: (a -> b) -> ReifiedGetter b c -> ReifiedGetter a c # rmap :: (b -> c) -> ReifiedGetter a b -> ReifiedGetter a c # (#.) :: forall a b c q. Coercible c b => q b c -> ReifiedGetter a b -> ReifiedGetter a c # (.#) :: forall a b c q. Coercible b a => ReifiedGetter b c -> q a b -> ReifiedGetter a c # | |
| Profunctor ReifiedFold | |
Defined in Control.Lens.Reified Methods dimap :: (a -> b) -> (c -> d) -> ReifiedFold b c -> ReifiedFold a d # lmap :: (a -> b) -> ReifiedFold b c -> ReifiedFold a c # rmap :: (b -> c) -> ReifiedFold a b -> ReifiedFold a c # (#.) :: forall a b c q. Coercible c b => q b c -> ReifiedFold a b -> ReifiedFold a c # (.#) :: forall a b c q. Coercible b a => ReifiedFold b c -> q a b -> ReifiedFold a c # | |
| Monad m => Profunctor (Kleisli m) | |
Defined in Data.Profunctor.Unsafe Methods dimap :: (a -> b) -> (c -> d) -> Kleisli m b c -> Kleisli m a d # lmap :: (a -> b) -> Kleisli m b c -> Kleisli m a c # rmap :: (b -> c) -> Kleisli m a b -> Kleisli m a c # (#.) :: forall a b c q. Coercible c b => q b c -> Kleisli m a b -> Kleisli m a c # (.#) :: forall a b c q. Coercible b a => Kleisli m b c -> q a b -> Kleisli m a c # | |
| Profunctor (Tagged :: Type -> Type -> Type) | |
Defined in Data.Profunctor.Unsafe Methods dimap :: (a -> b) -> (c -> d) -> Tagged b c -> Tagged a d # lmap :: (a -> b) -> Tagged b c -> Tagged a c # rmap :: (b -> c) -> Tagged a b -> Tagged a c # (#.) :: forall a b c q. Coercible c b => q b c -> Tagged a b -> Tagged a c # (.#) :: forall a b c q. Coercible b a => Tagged b c -> q a b -> Tagged a c # | |
| Profunctor (ReifiedIndexedGetter i) | |
Defined in Control.Lens.Reified Methods dimap :: (a -> b) -> (c -> d) -> ReifiedIndexedGetter i b c -> ReifiedIndexedGetter i a d # lmap :: (a -> b) -> ReifiedIndexedGetter i b c -> ReifiedIndexedGetter i a c # rmap :: (b -> c) -> ReifiedIndexedGetter i a b -> ReifiedIndexedGetter i a c # (#.) :: forall a b c q. Coercible c b => q b c -> ReifiedIndexedGetter i a b -> ReifiedIndexedGetter i a c # (.#) :: forall a b c q. Coercible b a => ReifiedIndexedGetter i b c -> q a b -> ReifiedIndexedGetter i a c # | |
| Profunctor (ReifiedIndexedFold i) | |
Defined in Control.Lens.Reified Methods dimap :: (a -> b) -> (c -> d) -> ReifiedIndexedFold i b c -> ReifiedIndexedFold i a d # lmap :: (a -> b) -> ReifiedIndexedFold i b c -> ReifiedIndexedFold i a c # rmap :: (b -> c) -> ReifiedIndexedFold i a b -> ReifiedIndexedFold i a c # (#.) :: forall a b c q. Coercible c b => q b c -> ReifiedIndexedFold i a b -> ReifiedIndexedFold i a c # (.#) :: forall a b c q. Coercible b a => ReifiedIndexedFold i b c -> q a b -> ReifiedIndexedFold i a c # | |
| Profunctor (Indexed i) | |
Defined in Control.Lens.Internal.Indexed Methods dimap :: (a -> b) -> (c -> d) -> Indexed i b c -> Indexed i a d # lmap :: (a -> b) -> Indexed i b c -> Indexed i a c # rmap :: (b -> c) -> Indexed i a b -> Indexed i a c # (#.) :: forall a b c q. Coercible c b => q b c -> Indexed i a b -> Indexed i a c # (.#) :: forall a b c q. Coercible b a => Indexed i b c -> q a b -> Indexed i a c # | |
| Profunctor p => Profunctor (TambaraSum p) | |
Defined in Data.Profunctor.Choice Methods dimap :: (a -> b) -> (c -> d) -> TambaraSum p b c -> TambaraSum p a d # lmap :: (a -> b) -> TambaraSum p b c -> TambaraSum p a c # rmap :: (b -> c) -> TambaraSum p a b -> TambaraSum p a c # (#.) :: forall a b c q. Coercible c b => q b c -> TambaraSum p a b -> TambaraSum p a c # (.#) :: forall a b c q. Coercible b a => TambaraSum p b c -> q a b -> TambaraSum p a c # | |
| Profunctor (PastroSum p) | |
Defined in Data.Profunctor.Choice Methods dimap :: (a -> b) -> (c -> d) -> PastroSum p b c -> PastroSum p a d # lmap :: (a -> b) -> PastroSum p b c -> PastroSum p a c # rmap :: (b -> c) -> PastroSum p a b -> PastroSum p a c # (#.) :: forall a b c q. Coercible c b => q b c -> PastroSum p a b -> PastroSum p a c # (.#) :: forall a b c q. Coercible b a => PastroSum p b c -> q a b -> PastroSum p a c # | |
| Profunctor (CotambaraSum p) | |
Defined in Data.Profunctor.Choice Methods dimap :: (a -> b) -> (c -> d) -> CotambaraSum p b c -> CotambaraSum p a d # lmap :: (a -> b) -> CotambaraSum p b c -> CotambaraSum p a c # rmap :: (b -> c) -> CotambaraSum p a b -> CotambaraSum p a c # (#.) :: forall a b c q. Coercible c b => q b c -> CotambaraSum p a b -> CotambaraSum p a c # (.#) :: forall a b c q. Coercible b a => CotambaraSum p b c -> q a b -> CotambaraSum p a c # | |
| Profunctor (CopastroSum p) | |
Defined in Data.Profunctor.Choice Methods dimap :: (a -> b) -> (c -> d) -> CopastroSum p b c -> CopastroSum p a d # lmap :: (a -> b) -> CopastroSum p b c -> CopastroSum p a c # rmap :: (b -> c) -> CopastroSum p a b -> CopastroSum p a c # (#.) :: forall a b c q. Coercible c b => q b c -> CopastroSum p a b -> CopastroSum p a c # (.#) :: forall a b c q. Coercible b a => CopastroSum p b c -> q a b -> CopastroSum p a c # | |
| Profunctor p => Profunctor (Tambara p) | |
Defined in Data.Profunctor.Strong Methods dimap :: (a -> b) -> (c -> d) -> Tambara p b c -> Tambara p a d # lmap :: (a -> b) -> Tambara p b c -> Tambara p a c # rmap :: (b -> c) -> Tambara p a b -> Tambara p a c # (#.) :: forall a b c q. Coercible c b => q b c -> Tambara p a b -> Tambara p a c # (.#) :: forall a b c q. Coercible b a => Tambara p b c -> q a b -> Tambara p a c # | |
| Profunctor (Pastro p) | |
Defined in Data.Profunctor.Strong Methods dimap :: (a -> b) -> (c -> d) -> Pastro p b c -> Pastro p a d # lmap :: (a -> b) -> Pastro p b c -> Pastro p a c # rmap :: (b -> c) -> Pastro p a b -> Pastro p a c # (#.) :: forall a b c q. Coercible c b => q b c -> Pastro p a b -> Pastro p a c # (.#) :: forall a b c q. Coercible b a => Pastro p b c -> q a b -> Pastro p a c # | |
| Profunctor (Cotambara p) | |
Defined in Data.Profunctor.Strong Methods dimap :: (a -> b) -> (c -> d) -> Cotambara p b c -> Cotambara p a d # lmap :: (a -> b) -> Cotambara p b c -> Cotambara p a c # rmap :: (b -> c) -> Cotambara p a b -> Cotambara p a c # (#.) :: forall a b c q. Coercible c b => q b c -> Cotambara p a b -> Cotambara p a c # (.#) :: forall a b c q. Coercible b a => Cotambara p b c -> q a b -> Cotambara p a c # | |
| Profunctor (Copastro p) | |
Defined in Data.Profunctor.Strong Methods dimap :: (a -> b) -> (c -> d) -> Copastro p b c -> Copastro p a d # lmap :: (a -> b) -> Copastro p b c -> Copastro p a c # rmap :: (b -> c) -> Copastro p a b -> Copastro p a c # (#.) :: forall a b c q. Coercible c b => q b c -> Copastro p a b -> Copastro p a c # (.#) :: forall a b c q. Coercible b a => Copastro p b c -> q a b -> Copastro p a c # | |
| Profunctor ((->) :: Type -> Type -> Type) | |
Defined in Data.Profunctor.Unsafe | |
| Functor w => Profunctor (Cokleisli w) | |
Defined in Data.Profunctor.Unsafe Methods dimap :: (a -> b) -> (c -> d) -> Cokleisli w b c -> Cokleisli w a d # lmap :: (a -> b) -> Cokleisli w b c -> Cokleisli w a c # rmap :: (b -> c) -> Cokleisli w a b -> Cokleisli w a c # (#.) :: forall a b c q. Coercible c b => q b c -> Cokleisli w a b -> Cokleisli w a c # (.#) :: forall a b c q. Coercible b a => Cokleisli w b c -> q a b -> Cokleisli w a c # | |
| (Profunctor p, Profunctor q) => Profunctor (Procompose p q) | |
Defined in Data.Profunctor.Composition Methods dimap :: (a -> b) -> (c -> d) -> Procompose p q b c -> Procompose p q a d # lmap :: (a -> b) -> Procompose p q b c -> Procompose p q a c # rmap :: (b -> c) -> Procompose p q a b -> Procompose p q a c # (#.) :: forall a b c q0. Coercible c b => q0 b c -> Procompose p q a b -> Procompose p q a c # (.#) :: forall a b c q0. Coercible b a => Procompose p q b c -> q0 a b -> Procompose p q a c # | |
| (Profunctor p, Profunctor q) => Profunctor (Rift p q) | |
Defined in Data.Profunctor.Composition Methods dimap :: (a -> b) -> (c -> d) -> Rift p q b c -> Rift p q a d # lmap :: (a -> b) -> Rift p q b c -> Rift p q a c # rmap :: (b -> c) -> Rift p q a b -> Rift p q a c # (#.) :: forall a b c q0. Coercible c b => q0 b c -> Rift p q a b -> Rift p q a c # (.#) :: forall a b c q0. Coercible b a => Rift p q b c -> q0 a b -> Rift p q a c # | |
| Functor f => Profunctor (Joker f :: Type -> Type -> Type) | |
Defined in Data.Profunctor.Unsafe Methods dimap :: (a -> b) -> (c -> d) -> Joker f b c -> Joker f a d # lmap :: (a -> b) -> Joker f b c -> Joker f a c # rmap :: (b -> c) -> Joker f a b -> Joker f a c # (#.) :: forall a b c q. Coercible c b => q b c -> Joker f a b -> Joker f a c # (.#) :: forall a b c q. Coercible b a => Joker f b c -> q a b -> Joker f a c # | |
| Contravariant f => Profunctor (Clown f :: Type -> Type -> Type) | |
Defined in Data.Profunctor.Unsafe Methods dimap :: (a -> b) -> (c -> d) -> Clown f b c -> Clown f a d # lmap :: (a -> b) -> Clown f b c -> Clown f a c # rmap :: (b -> c) -> Clown f a b -> Clown f a c # (#.) :: forall a b c q. Coercible c b => q b c -> Clown f a b -> Clown f a c # (.#) :: forall a b c q. Coercible b a => Clown f b c -> q a b -> Clown f a c # | |
| (Profunctor p, Profunctor q) => Profunctor (Sum p q) | |
Defined in Data.Profunctor.Unsafe Methods dimap :: (a -> b) -> (c -> d) -> Sum p q b c -> Sum p q a d # lmap :: (a -> b) -> Sum p q b c -> Sum p q a c # rmap :: (b -> c) -> Sum p q a b -> Sum p q a c # (#.) :: forall a b c q0. Coercible c b => q0 b c -> Sum p q a b -> Sum p q a c # (.#) :: forall a b c q0. Coercible b a => Sum p q b c -> q0 a b -> Sum p q a c # | |
| (Profunctor p, Profunctor q) => Profunctor (Product p q) | |
Defined in Data.Profunctor.Unsafe Methods dimap :: (a -> b) -> (c -> d) -> Product p q b c -> Product p q a d # lmap :: (a -> b) -> Product p q b c -> Product p q a c # rmap :: (b -> c) -> Product p q a b -> Product p q a c # (#.) :: forall a b c q0. Coercible c b => q0 b c -> Product p q a b -> Product p q a c # (.#) :: forall a b c q0. Coercible b a => Product p q b c -> q0 a b -> Product p q a c # | |
| (Functor f, Profunctor p) => Profunctor (Tannen f p) | |
Defined in Data.Profunctor.Unsafe Methods dimap :: (a -> b) -> (c -> d) -> Tannen f p b c -> Tannen f p a d # lmap :: (a -> b) -> Tannen f p b c -> Tannen f p a c # rmap :: (b -> c) -> Tannen f p a b -> Tannen f p a c # (#.) :: forall a b c q. Coercible c b => q b c -> Tannen f p a b -> Tannen f p a c # (.#) :: forall a b c q. Coercible b a => Tannen f p b c -> q a b -> Tannen f p a c # | |
| (Profunctor p, Functor f, Functor g) => Profunctor (Biff p f g) | |
Defined in Data.Profunctor.Unsafe Methods dimap :: (a -> b) -> (c -> d) -> Biff p f g b c -> Biff p f g a d # lmap :: (a -> b) -> Biff p f g b c -> Biff p f g a c # rmap :: (b -> c) -> Biff p f g a b -> Biff p f g a c # (#.) :: forall a b c q. Coercible c b => q b c -> Biff p f g a b -> Biff p f g a c # (.#) :: forall a b c q. Coercible b a => Biff p f g b c -> q a b -> Biff p f g a c # | |
class Profunctor p => Strong (p :: Type -> Type -> Type) where #
Generalizing Star of a strong Functor
Note: Every Functor in Haskell is strong with respect to (,).
This describes profunctor strength with respect to the product structure of Hask.
Methods
Instances
class Profunctor p => Choice (p :: Type -> Type -> Type) where #
The generalization of Costar of Functor that is strong with respect
to Either.
Note: This is also a notion of strength, except with regards to another monoidal structure that we can choose to equip Hask with: the cocartesian coproduct.
Methods
left' :: p a b -> p (Either a c) (Either b c) #
Laws:
left'≡dimapswapE swapE.right'where swapE ::Eithera b ->Eitherb a swapE =eitherRightLeftrmapLeft≡lmapLeft.left'lmap(rightf).left'≡rmap(rightf).left'left'.left'≡dimapassocE unassocE.left'where assocE ::Either(Eithera b) c ->Eithera (Eitherb c) assocE (Left(Lefta)) =Lefta assocE (Left(Rightb)) =Right(Leftb) assocE (Rightc) =Right(Rightc) unassocE ::Eithera (Eitherb c) ->Either(Eithera b) c unassocE (Lefta) =Left(Lefta) unassocE (Right(Leftb)) =Left(Rightb) unassocE (Right(Rightc)) =Rightc
right' :: p a b -> p (Either c a) (Either c b) #
Laws:
right'≡dimapswapE swapE.left'where swapE ::Eithera b ->Eitherb a swapE =eitherRightLeftrmapRight≡lmapRight.right'lmap(leftf).right'≡rmap(leftf).right'right'.right'≡dimapunassocE assocE.right'where assocE ::Either(Eithera b) c ->Eithera (Eitherb c) assocE (Left(Lefta)) =Lefta assocE (Left(Rightb)) =Right(Leftb) assocE (Rightc) =Right(Rightc) unassocE ::Eithera (Eitherb c) ->Either(Eithera b) c unassocE (Lefta) =Left(Lefta) unassocE (Right(Leftb)) =Left(Rightb) unassocE (Right(Rightc)) =Rightc
Instances
Category
class Category (cat :: k -> k -> Type) where #
A class for categories. Instances should satisfy the laws
Methods
id :: forall (a :: k). cat a a #
the identity morphism
(.) :: forall (b :: k) (c :: k) (a :: k). cat b c -> cat a b -> cat a c infixr 9 #
morphism composition
Instances
| Category (Coercion :: k -> k -> Type) | Since: base-4.7.0.0 |
| Category ((:~:) :: k -> k -> Type) | Since: base-4.7.0.0 |
| Category ((:~~:) :: k -> k -> Type) | Since: base-4.10.0.0 |
| (Category p, Category q) => Category (Product p q :: k -> k -> Type) | |
| (Applicative f, Category p) => Category (Tannen f p :: k -> k -> Type) | |
| Category Op | |
| Category ReifiedGetter | |
Defined in Control.Lens.Reified Methods id :: forall (a :: k). ReifiedGetter a a # (.) :: forall (b :: k) (c :: k) (a :: k). ReifiedGetter b c -> ReifiedGetter a b -> ReifiedGetter a c # | |
| Category ReifiedFold | |
Defined in Control.Lens.Reified Methods id :: forall (a :: k). ReifiedFold a a # (.) :: forall (b :: k) (c :: k) (a :: k). ReifiedFold b c -> ReifiedFold a b -> ReifiedFold a c # | |
| Monad m => Category (Kleisli m :: Type -> Type -> Type) | Since: base-3.0 |
| (Applicative f, Monad f) => Category (WhenMissing f :: Type -> Type -> Type) | Since: containers-0.5.9 |
Defined in Data.IntMap.Internal Methods id :: forall (a :: k). WhenMissing f a a # (.) :: forall (b :: k) (c :: k) (a :: k). WhenMissing f b c -> WhenMissing f a b -> WhenMissing f a c # | |
| Category (Indexed i :: Type -> Type -> Type) | |
| Category p => Category (TambaraSum p :: Type -> Type -> Type) | |
Defined in Data.Profunctor.Choice Methods id :: forall (a :: k). TambaraSum p a a # (.) :: forall (b :: k) (c :: k) (a :: k). TambaraSum p b c -> TambaraSum p a b -> TambaraSum p a c # | |
| Category p => Category (Tambara p :: Type -> Type -> Type) | |
| Category ((->) :: Type -> Type -> Type) | Since: base-3.0 |
Defined in Control.Category | |
| Comonad w => Category (Cokleisli w :: Type -> Type -> Type) | |
| (Monad f, Applicative f) => Category (WhenMatched f x :: Type -> Type -> Type) | Since: containers-0.5.9 |
Defined in Data.IntMap.Internal Methods id :: forall (a :: k). WhenMatched f x a a # (.) :: forall (b :: k) (c :: k) (a :: k). WhenMatched f x b c -> WhenMatched f x a b -> WhenMatched f x a c # | |
| (Applicative f, Monad f) => Category (WhenMissing f k :: Type -> Type -> Type) | Since: containers-0.5.9 |
Defined in Data.Map.Internal Methods id :: forall (a :: k0). WhenMissing f k a a # (.) :: forall (b :: k0) (c :: k0) (a :: k0). WhenMissing f k b c -> WhenMissing f k a b -> WhenMissing f k a c # | |
| p ~ q => Category (Rift p q :: Type -> Type -> Type) |
|
| (Monad f, Applicative f) => Category (WhenMatched f k x :: Type -> Type -> Type) | Since: containers-0.5.9 |
Defined in Data.Map.Internal Methods id :: forall (a :: k0). WhenMatched f k x a a # (.) :: forall (b :: k0) (c :: k0) (a :: k0). WhenMatched f k x b c -> WhenMatched f k x a b -> WhenMatched f k x a c # | |
class Category a => Arrow (a :: Type -> Type -> Type) where #
The basic arrow class.
Instances should satisfy the following laws:
arrid =idarr(f >>> g) =arrf >>>arrgfirst(arrf) =arr(firstf)first(f >>> g) =firstf >>>firstgfirstf >>>arrfst=arrfst>>> ffirstf >>>arr(id*** g) =arr(id*** g) >>>firstffirst(firstf) >>>arrassoc =arrassoc >>>firstf
where
assoc ((a,b),c) = (a,(b,c))
The other combinators have sensible default definitions, which may be overridden for efficiency.
Methods
Lift a function to an arrow.
first :: a b c -> a (b, d) (c, d) #
Send the first component of the input through the argument arrow, and copy the rest unchanged to the output.
second :: a b c -> a (d, b) (d, c) #
A mirror image of first.
The default definition may be overridden with a more efficient version if desired.
(***) :: a b c -> a b' c' -> a (b, b') (c, c') infixr 3 #
Split the input between the two argument arrows and combine their output. Note that this is in general not a functor.
The default definition may be overridden with a more efficient version if desired.
(&&&) :: a b c -> a b c' -> a b (c, c') infixr 3 #
Fanout: send the input to both argument arrows and combine their output.
The default definition may be overridden with a more efficient version if desired.
Instances
| Arrow ReifiedGetter | |
Defined in Control.Lens.Reified Methods arr :: (b -> c) -> ReifiedGetter b c # first :: ReifiedGetter b c -> ReifiedGetter (b, d) (c, d) # second :: ReifiedGetter b c -> ReifiedGetter (d, b) (d, c) # (***) :: ReifiedGetter b c -> ReifiedGetter b' c' -> ReifiedGetter (b, b') (c, c') # (&&&) :: ReifiedGetter b c -> ReifiedGetter b c' -> ReifiedGetter b (c, c') # | |
| Arrow ReifiedFold | |
Defined in Control.Lens.Reified Methods arr :: (b -> c) -> ReifiedFold b c # first :: ReifiedFold b c -> ReifiedFold (b, d) (c, d) # second :: ReifiedFold b c -> ReifiedFold (d, b) (d, c) # (***) :: ReifiedFold b c -> ReifiedFold b' c' -> ReifiedFold (b, b') (c, c') # (&&&) :: ReifiedFold b c -> ReifiedFold b c' -> ReifiedFold b (c, c') # | |
| Monad m => Arrow (Kleisli m) | Since: base-2.1 |
Defined in Control.Arrow | |
| Arrow (Indexed i) | |
Defined in Control.Lens.Internal.Indexed | |
| Arrow p => Arrow (Tambara p) | |
Defined in Data.Profunctor.Strong | |
| Arrow ((->) :: Type -> Type -> Type) | Since: base-2.1 |
| Comonad w => Arrow (Cokleisli w) | |
Defined in Control.Comonad Methods arr :: (b -> c) -> Cokleisli w b c # first :: Cokleisli w b c -> Cokleisli w (b, d) (c, d) # second :: Cokleisli w b c -> Cokleisli w (d, b) (d, c) # (***) :: Cokleisli w b c -> Cokleisli w b' c' -> Cokleisli w (b, b') (c, c') # (&&&) :: Cokleisli w b c -> Cokleisli w b c' -> Cokleisli w b (c, c') # | |
| (Arrow p, Arrow q) => Arrow (Product p q) | |
Defined in Data.Bifunctor.Product Methods arr :: (b -> c) -> Product p q b c # first :: Product p q b c -> Product p q (b, d) (c, d) # second :: Product p q b c -> Product p q (d, b) (d, c) # (***) :: Product p q b c -> Product p q b' c' -> Product p q (b, b') (c, c') # (&&&) :: Product p q b c -> Product p q b c' -> Product p q b (c, c') # | |
| (Applicative f, Arrow p) => Arrow (Tannen f p) | |
Defined in Data.Bifunctor.Tannen | |
data Kleisli (m :: Type -> Type) a b #
Kleisli arrows of a monad.
Instances
| Monad m => Arrow (Kleisli m) | Since: base-2.1 |
Defined in Control.Arrow | |
| MonadPlus m => ArrowZero (Kleisli m) | Since: base-2.1 |
Defined in Control.Arrow | |
| MonadPlus m => ArrowPlus (Kleisli m) | Since: base-2.1 |
| Monad m => ArrowChoice (Kleisli m) | Since: base-2.1 |
Defined in Control.Arrow | |
| Monad m => ArrowApply (Kleisli m) | Since: base-2.1 |
Defined in Control.Arrow | |
| MonadFix m => ArrowLoop (Kleisli m) | Beware that for many monads (those for which the Since: base-2.1 |
Defined in Control.Arrow | |
| Monad m => Profunctor (Kleisli m) | |
Defined in Data.Profunctor.Unsafe Methods dimap :: (a -> b) -> (c -> d) -> Kleisli m b c -> Kleisli m a d # lmap :: (a -> b) -> Kleisli m b c -> Kleisli m a c # rmap :: (b -> c) -> Kleisli m a b -> Kleisli m a c # (#.) :: forall a b c q. Coercible c b => q b c -> Kleisli m a b -> Kleisli m a c # (.#) :: forall a b c q. Coercible b a => Kleisli m b c -> q a b -> Kleisli m a c # | |
| (Monad m, Functor m) => Representable (Kleisli m) | |
| MonadFix m => Costrong (Kleisli m) | |
| Monad m => Strong (Kleisli m) | |
| Monad m => Choice (Kleisli m) | |
| Monad m => Category (Kleisli m :: Type -> Type -> Type) | Since: base-3.0 |
| Generic1 (Kleisli m a :: Type -> Type) | Since: base-4.14.0.0 |
| Monad m => Monad (Kleisli m a) | Since: base-4.14.0.0 |
| Functor m => Functor (Kleisli m a) | Since: base-4.14.0.0 |
| Applicative m => Applicative (Kleisli m a) | Since: base-4.14.0.0 |
Defined in Control.Arrow | |
| Alternative m => Alternative (Kleisli m a) | Since: base-4.14.0.0 |
| MonadPlus m => MonadPlus (Kleisli m a) | Since: base-4.14.0.0 |
| Generic (Kleisli m a b) | Since: base-4.14.0.0 |
| Wrapped (Kleisli m a b) | |
| t ~ Kleisli m' a' b' => Rewrapped (Kleisli m a b) t | |
Defined in Control.Lens.Wrapped | |
| type Rep (Kleisli m) | |
Defined in Data.Profunctor.Rep | |
| type Rep1 (Kleisli m a :: Type -> Type) | |
| type Rep (Kleisli m a b) | |
Defined in Control.Arrow | |
| type Unwrapped (Kleisli m a b) | |
Defined in Control.Lens.Wrapped | |
(>>>) :: forall k cat (a :: k) (b :: k) (c :: k). Category cat => cat a b -> cat b c -> cat a c infixr 1 #
Left-to-right composition
(<<<) :: forall k cat (b :: k) (c :: k) (a :: k). Category cat => cat b c -> cat a b -> cat a c infixr 1 #
Right-to-left composition
EnvT
data EnvT e (w :: Type -> Type) a #
Constructors
| EnvT e (w a) |
Instances
| ComonadTrans (EnvT e) | |
Defined in Control.Comonad.Trans.Env | |
| ComonadHoist (EnvT e) | |
| Functor w => Functor (EnvT e w) | |
| (Monoid e, Applicative m) => Applicative (EnvT e m) | |
| Foldable w => Foldable (EnvT e w) | |
Defined in Control.Comonad.Trans.Env Methods fold :: Monoid m => EnvT e w m -> m # foldMap :: Monoid m => (a -> m) -> EnvT e w a -> m # foldMap' :: Monoid m => (a -> m) -> EnvT e w a -> m # foldr :: (a -> b -> b) -> b -> EnvT e w a -> b # foldr' :: (a -> b -> b) -> b -> EnvT e w a -> b # foldl :: (b -> a -> b) -> b -> EnvT e w a -> b # foldl' :: (b -> a -> b) -> b -> EnvT e w a -> b # foldr1 :: (a -> a -> a) -> EnvT e w a -> a # foldl1 :: (a -> a -> a) -> EnvT e w a -> a # elem :: Eq a => a -> EnvT e w a -> Bool # maximum :: Ord a => EnvT e w a -> a # minimum :: Ord a => EnvT e w a -> a # | |
| Traversable w => Traversable (EnvT e w) | |
Defined in Control.Comonad.Trans.Env | |
| Comonad w => Comonad (EnvT e w) | |
| (Semigroup e, ComonadApply w) => ComonadApply (EnvT e w) | |
| (Data e, Typeable w, Data (w a), Data a) => Data (EnvT e w a) | |
Defined in Control.Comonad.Trans.Env Methods gfoldl :: (forall d b. Data d => c (d -> b) -> d -> c b) -> (forall g. g -> c g) -> EnvT e w a -> c (EnvT e w a) # gunfold :: (forall b r. Data b => c (b -> r) -> c r) -> (forall r. r -> c r) -> Constr -> c (EnvT e w a) # toConstr :: EnvT e w a -> Constr # dataTypeOf :: EnvT e w a -> DataType # dataCast1 :: Typeable t => (forall d. Data d => c (t d)) -> Maybe (c (EnvT e w a)) # dataCast2 :: Typeable t => (forall d e0. (Data d, Data e0) => c (t d e0)) -> Maybe (c (EnvT e w a)) # gmapT :: (forall b. Data b => b -> b) -> EnvT e w a -> EnvT e w a # gmapQl :: (r -> r' -> r) -> r -> (forall d. Data d => d -> r') -> EnvT e w a -> r # gmapQr :: forall r r'. (r' -> r -> r) -> r -> (forall d. Data d => d -> r') -> EnvT e w a -> r # gmapQ :: (forall d. Data d => d -> u) -> EnvT e w a -> [u] # gmapQi :: Int -> (forall d. Data d => d -> u) -> EnvT e w a -> u # gmapM :: Monad m => (forall d. Data d => d -> m d) -> EnvT e w a -> m (EnvT e w a) # gmapMp :: MonadPlus m => (forall d. Data d => d -> m d) -> EnvT e w a -> m (EnvT e w a) # gmapMo :: MonadPlus m => (forall d. Data d => d -> m d) -> EnvT e w a -> m (EnvT e w a) # | |
Extensible Records
data Rec (a :: u -> Type) (b :: [u]) where #
A record is parameterized by a universe u, an interpretation f and a
list of rows rs. The labels or indices of the record are given by
inhabitants of the kind u; the type of values at any label r :: u is
given by its interpretation f r :: *.
Constructors
| RNil :: forall u (a :: u -> Type). Rec a ('[] :: [u]) | |
| (:&) :: forall u (a :: u -> Type) (r :: u) (rs :: [u]). !(a r) -> !(Rec a rs) -> Rec a (r ': rs) infixr 7 |
Instances
| RecSubset (Rec :: (k -> Type) -> [k] -> Type) ('[] :: [k]) (ss :: [k]) ('[] :: [Nat]) | |
Defined in Data.Vinyl.Lens Associated Types type RecSubsetFCtx Rec f # Methods rsubsetC :: forall g (f :: k0 -> Type). (Functor g, RecSubsetFCtx Rec f) => (Rec f '[] -> g (Rec f '[])) -> Rec f ss -> g (Rec f ss) # rcastC :: forall (f :: k0 -> Type). RecSubsetFCtx Rec f => Rec f ss -> Rec f '[] # rreplaceC :: forall (f :: k0 -> Type). RecSubsetFCtx Rec f => Rec f '[] -> Rec f ss -> Rec f ss # | |
| (RElem r ss i, RSubset rs ss is) => RecSubset (Rec :: (k -> Type) -> [k] -> Type) (r ': rs :: [k]) (ss :: [k]) (i ': is) | |
Defined in Data.Vinyl.Lens Associated Types type RecSubsetFCtx Rec f # Methods rsubsetC :: forall g (f :: k0 -> Type). (Functor g, RecSubsetFCtx Rec f) => (Rec f (r ': rs) -> g (Rec f (r ': rs))) -> Rec f ss -> g (Rec f ss) # rcastC :: forall (f :: k0 -> Type). RecSubsetFCtx Rec f => Rec f ss -> Rec f (r ': rs) # rreplaceC :: forall (f :: k0 -> Type). RecSubsetFCtx Rec f => Rec f (r ': rs) -> Rec f ss -> Rec f ss # | |
| RecElem (Rec :: (a -> Type) -> [a] -> Type) (r :: a) (r' :: a) (r ': rs :: [a]) (r' ': rs :: [a]) 'Z | |
Defined in Data.Vinyl.Lens Associated Types type RecElemFCtx Rec f # | |
| (RIndex r (s ': rs) ~ 'S i, RecElem (Rec :: (a -> Type) -> [a] -> Type) r r' rs rs' i) => RecElem (Rec :: (a -> Type) -> [a] -> Type) (r :: a) (r' :: a) (s ': rs :: [a]) (s ': rs' :: [a]) ('S i) | |
Defined in Data.Vinyl.Lens Associated Types type RecElemFCtx Rec f # | |
| TestCoercion f => TestCoercion (Rec f :: [u] -> Type) | |
Defined in Data.Vinyl.Core | |
| TestEquality f => TestEquality (Rec f :: [u] -> Type) | |
Defined in Data.Vinyl.Core | |
| Eq (Rec f ('[] :: [u])) | |
| (Eq (f r), Eq (Rec f rs)) => Eq (Rec f (r ': rs)) | |
| Ord (Rec f ('[] :: [u])) | |
| (Ord (f r), Ord (Rec f rs)) => Ord (Rec f (r ': rs)) | |
Defined in Data.Vinyl.Core Methods compare :: Rec f (r ': rs) -> Rec f (r ': rs) -> Ordering # (<) :: Rec f (r ': rs) -> Rec f (r ': rs) -> Bool # (<=) :: Rec f (r ': rs) -> Rec f (r ': rs) -> Bool # (>) :: Rec f (r ': rs) -> Rec f (r ': rs) -> Bool # (>=) :: Rec f (r ': rs) -> Rec f (r ': rs) -> Bool # max :: Rec f (r ': rs) -> Rec f (r ': rs) -> Rec f (r ': rs) # min :: Rec f (r ': rs) -> Rec f (r ': rs) -> Rec f (r ': rs) # | |
| (RMap rs, ReifyConstraint Show f rs, RecordToList rs) => Show (Rec f rs) | Records may be shown insofar as their points may be shown.
|
| Generic (Rec f ('[] :: [u])) | |
| Generic (Rec f rs) => Generic (Rec f (r ': rs)) | |
| Semigroup (Rec f ('[] :: [u])) | |
| (Semigroup (f r), Semigroup (Rec f rs)) => Semigroup (Rec f (r ': rs)) | |
| Monoid (Rec f ('[] :: [u])) | |
| (Monoid (f r), Monoid (Rec f rs)) => Monoid (Rec f (r ': rs)) | |
| Storable (Rec f ('[] :: [u])) | |
Defined in Data.Vinyl.Core | |
| (Storable (f r), Storable (Rec f rs)) => Storable (Rec f (r ': rs)) | |
Defined in Data.Vinyl.Core Methods sizeOf :: Rec f (r ': rs) -> Int # alignment :: Rec f (r ': rs) -> Int # peekElemOff :: Ptr (Rec f (r ': rs)) -> Int -> IO (Rec f (r ': rs)) # pokeElemOff :: Ptr (Rec f (r ': rs)) -> Int -> Rec f (r ': rs) -> IO () # peekByteOff :: Ptr b -> Int -> IO (Rec f (r ': rs)) # pokeByteOff :: Ptr b -> Int -> Rec f (r ': rs) -> IO () # | |
| ReifyConstraint NFData f xs => NFData (Rec f xs) | |
Defined in Data.Vinyl.Core | |
| type RecSubsetFCtx (Rec :: (k -> Type) -> [k] -> Type) (f :: k -> Type) | |
Defined in Data.Vinyl.Lens | |
| type RecSubsetFCtx (Rec :: (k -> Type) -> [k] -> Type) (f :: k -> Type) | |
Defined in Data.Vinyl.Lens | |
| type RecElemFCtx (Rec :: (a -> Type) -> [a] -> Type) (f :: a -> Type) | |
Defined in Data.Vinyl.Lens | |
| type RecElemFCtx (Rec :: (a -> Type) -> [a] -> Type) (f :: a -> Type) | |
Defined in Data.Vinyl.Lens | |
| type Rep (Rec f (r ': rs)) | |
Defined in Data.Vinyl.Core type Rep (Rec f (r ': rs)) = C1 ('MetaCons ":&" ('InfixI 'RightAssociative 7) 'False) (S1 ('MetaSel ('Nothing :: Maybe Symbol) 'NoSourceUnpackedness 'SourceStrict 'DecidedStrict) (Rec0 (f r)) :*: S1 ('MetaSel ('Nothing :: Maybe Symbol) 'NoSourceUnpackedness 'NoSourceStrictness 'DecidedLazy) (Rep (Rec f rs))) | |
| type Rep (Rec f ('[] :: [u])) | |
Defined in Data.Vinyl.Core | |
Rec _ rs with labels in kind u gives rise to a functor Hask^u ->
Hask; that is, a natural transformation between two interpretation functors
f,g may be used to transport a value from Rec f rs to Rec g rs.
Minimal complete definition
rtraverse :: forall u h f g (rs :: [u]). Applicative h => (forall (x :: u). f x -> h (g x)) -> Rec f rs -> h (Rec g rs) #
A record may be traversed with respect to its interpretation functor. This can be used to yank (some or all) effects from the fields of the record to the outside of the record.
rcast :: forall k1 k2 (rs :: [k1]) (ss :: [k1]) (f :: k2 -> Type) record (is :: [Nat]). (RecSubset record rs ss is, RecSubsetFCtx record f) => record f ss -> record f rs #
Takes a larger record to a smaller one by forgetting fields. This
is rcastC with the type arguments reordered for more convenient
usage with TypeApplications.
data CoRec (a :: u -> Type) (b :: [u]) where #
CoRef f rs represents a single value of type f r for some r in rs.
Constructors
| CoVal :: forall u (r :: u) (b :: [u]) (a :: u -> Type). r ∈ b => !(a r) -> CoRec a b | Witness that |
Instances
| (RMap rs, RecAll Maybe rs Eq, RecApplicative rs, RecordToList rs, ReifyConstraint Eq Maybe rs) => Eq (CoRec Identity rs) | |
| (AllHave '[Show] rs, RecApplicative rs) => Show (CoRec Identity rs) | |
type (∈) (r :: k) (rs :: [k]) = RElem r rs (RIndex r rs) #
A shorthand for RElem which supplies its index.
Compose
data Compose (f :: l -> Type) (g :: k -> l) (x :: k) #
Instances
| (IsoHKD f (HKD g a), IsoHKD g a, Functor f) => IsoHKD (Compose f g :: k -> Type) (a :: k) | Work with values of type |
| (Functor f, Functor g) => Functor (Compose f g) | |
| (Applicative f, Applicative g) => Applicative (Compose f g) | |
Defined in Data.Vinyl.Functor | |
| (Foldable f, Foldable g) => Foldable (Compose f g) | |
Defined in Data.Vinyl.Functor 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 # | |
| (Traversable f, Traversable g) => Traversable (Compose f g) | |
Defined in Data.Vinyl.Functor | |
| Show (f (g a)) => Show (Compose f g a) | |
| Generic (Compose f g x) | |
| Semigroup (f (g a)) => Semigroup (Compose f g a) | |
| Monoid (f (g a)) => Monoid (Compose f g a) | |
| Storable (f (g x)) => Storable (Compose f g x) | |
Defined in Data.Vinyl.Functor Methods sizeOf :: Compose f g x -> Int # alignment :: Compose f g x -> Int # peekElemOff :: Ptr (Compose f g x) -> Int -> IO (Compose f g x) # pokeElemOff :: Ptr (Compose f g x) -> Int -> Compose f g x -> IO () # peekByteOff :: Ptr b -> Int -> IO (Compose f g x) # pokeByteOff :: Ptr b -> Int -> Compose f g x -> IO () # | |
| type HKD (Compose f g :: k -> Type) (a :: k) | |
| type Rep (Compose f g x) | |
Defined in Data.Vinyl.Functor | |
onCompose :: forall l1 k1 l2 f (g :: k1 -> l1) (a :: k1) h (k2 :: k1 -> l2). (f (g a) -> h (k2 a)) -> (f :. g) a -> (h :. k2) a #
Generic
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
Time
This is the simplest representation of UTC. It consists of the day number, and a time offset from midnight. Note that if a day has a leap second added to it, it will have 86401 seconds.
Instances
| Eq UTCTime | |
| Data UTCTime | |
Defined in Data.Time.Clock.Internal.UTCTime Methods gfoldl :: (forall d b. Data d => c (d -> b) -> d -> c b) -> (forall g. g -> c g) -> UTCTime -> c UTCTime # gunfold :: (forall b r. Data b => c (b -> r) -> c r) -> (forall r. r -> c r) -> Constr -> c UTCTime # toConstr :: UTCTime -> Constr # dataTypeOf :: UTCTime -> DataType # dataCast1 :: Typeable t => (forall d. Data d => c (t d)) -> Maybe (c UTCTime) # dataCast2 :: Typeable t => (forall d e. (Data d, Data e) => c (t d e)) -> Maybe (c UTCTime) # gmapT :: (forall b. Data b => b -> b) -> UTCTime -> UTCTime # gmapQl :: (r -> r' -> r) -> r -> (forall d. Data d => d -> r') -> UTCTime -> r # gmapQr :: forall r r'. (r' -> r -> r) -> r -> (forall d. Data d => d -> r') -> UTCTime -> r # gmapQ :: (forall d. Data d => d -> u) -> UTCTime -> [u] # gmapQi :: Int -> (forall d. Data d => d -> u) -> UTCTime -> u # gmapM :: Monad m => (forall d. Data d => d -> m d) -> UTCTime -> m UTCTime # gmapMp :: MonadPlus m => (forall d. Data d => d -> m d) -> UTCTime -> m UTCTime # gmapMo :: MonadPlus m => (forall d. Data d => d -> m d) -> UTCTime -> m UTCTime # | |
| Ord UTCTime | |
Defined in Data.Time.Clock.Internal.UTCTime | |
| NFData UTCTime | |
Defined in Data.Time.Clock.Internal.UTCTime | |
Path
Path of some base and type.
The type variables are:
b— base, the base location of the path; absolute or relative.t— type, whether file or directory.
Internally is a string. The string can be of two formats only:
- File format:
file.txt,foo/bar.txt,/foo/bar.txt - Directory format:
foo/,/foo/bar/
All directories end in a trailing separator. There are no duplicate
path separators //, no .., no ./, no ~/, etc.
Instances
| (Typeable b, Typeable t) => Lift (Path b t :: Type) | |
| Eq (Path b t) | String equality. The following property holds: show x == show y ≡ x == y |
| (Data b, Data t) => Data (Path b t) | |
Defined in Path.Internal.Posix Methods gfoldl :: (forall d b0. Data d => c (d -> b0) -> d -> c b0) -> (forall g. g -> c g) -> Path b t -> c (Path b t) # gunfold :: (forall b0 r. Data b0 => c (b0 -> r) -> c r) -> (forall r. r -> c r) -> Constr -> c (Path b t) # toConstr :: Path b t -> Constr # dataTypeOf :: Path b t -> DataType # dataCast1 :: Typeable t0 => (forall d. Data d => c (t0 d)) -> Maybe (c (Path b t)) # dataCast2 :: Typeable t0 => (forall d e. (Data d, Data e) => c (t0 d e)) -> Maybe (c (Path b t)) # gmapT :: (forall b0. Data b0 => b0 -> b0) -> Path b t -> Path b t # gmapQl :: (r -> r' -> r) -> r -> (forall d. Data d => d -> r') -> Path b t -> r # gmapQr :: forall r r'. (r' -> r -> r) -> r -> (forall d. Data d => d -> r') -> Path b t -> r # gmapQ :: (forall d. Data d => d -> u) -> Path b t -> [u] # gmapQi :: Int -> (forall d. Data d => d -> u) -> Path b t -> u # gmapM :: Monad m => (forall d. Data d => d -> m d) -> Path b t -> m (Path b t) # gmapMp :: MonadPlus m => (forall d. Data d => d -> m d) -> Path b t -> m (Path b t) # gmapMo :: MonadPlus m => (forall d. Data d => d -> m d) -> Path b t -> m (Path b t) # | |
| Ord (Path b t) | String ordering. The following property holds: show x `compare` show y ≡ x `compare` y |
Defined in Path.Internal.Posix | |
| Show (Path b t) | Same as 'show . Path.toFilePath'. The following property holds: x == y ≡ show x == show y |
| Generic (Path b t) | |
| Hashable (Path b t) | |
Defined in Path.Internal.Posix | |
| ToJSON (Path b t) | |
Defined in Path.Internal.Posix | |
| ToJSONKey (Path b t) | |
Defined in Path.Internal.Posix | |
| FromJSON (Path Abs File) | |
| FromJSON (Path Abs Dir) | |
| FromJSON (Path Rel File) | |
| FromJSON (Path Rel Dir) | |
| FromJSONKey (Path Abs File) | |
Defined in Path.Posix Methods | |
| FromJSONKey (Path Abs Dir) | |
Defined in Path.Posix Methods | |
| FromJSONKey (Path Rel File) | |
Defined in Path.Posix Methods | |
| FromJSONKey (Path Rel Dir) | |
Defined in Path.Posix Methods | |
| NFData (Path b t) | |
Defined in Path.Internal.Posix | |
| type Rep (Path b t) | |
Defined in Path.Internal.Posix | |
A relative path; one without a root. Note that a .. path component to
represent the parent directory is not allowed by this library.
Instances
| FromJSON (Path Rel File) | |
| FromJSON (Path Rel Dir) | |
| FromJSONKey (Path Rel File) | |
Defined in Path.Posix Methods | |
| FromJSONKey (Path Rel Dir) | |
Defined in Path.Posix Methods | |
An absolute path.
Instances
| FromJSON (Path Abs File) | |
| FromJSON (Path Abs Dir) | |
| FromJSONKey (Path Abs File) | |
Defined in Path.Posix Methods | |
| FromJSONKey (Path Abs Dir) | |
Defined in Path.Posix Methods | |
A file path.
Instances
| FromJSON (SomeBase File) | |
| FromJSON (Path Abs File) | |
| FromJSON (Path Rel File) | |
| FromJSONKey (Path Abs File) | |
Defined in Path.Posix Methods | |
| FromJSONKey (Path Rel File) | |
Defined in Path.Posix Methods | |
A directory path.
Instances
| FromJSON (SomeBase Dir) | |
| FromJSON (Path Abs Dir) | |
| FromJSON (Path Rel Dir) | |
| FromJSONKey (Path Abs Dir) | |
Defined in Path.Posix Methods | |
| FromJSONKey (Path Rel Dir) | |
Defined in Path.Posix Methods | |
(</>) :: Path b Dir -> Path Rel t -> Path b t infixr 5 #
Append two paths.
The following cases are valid and the equalities hold:
$(mkAbsDir x) </> $(mkRelDir y) = $(mkAbsDir (x ++ "/" ++ y))
$(mkAbsDir x) </> $(mkRelFile y) = $(mkAbsFile (x ++ "/" ++ y))
$(mkRelDir x) </> $(mkRelDir y) = $(mkRelDir (x ++ "/" ++ y))
$(mkRelDir x) </> $(mkRelFile y) = $(mkRelFile (x ++ "/" ++ y))
The following are proven not possible to express:
$(mkAbsFile …) </> x
$(mkRelFile …) </> x
x </> $(mkAbsFile …)
x </> $(mkAbsDir …)
flip :: (a -> b -> c) -> b -> a -> c #
takes its (first) two arguments in the reverse order of flip ff.
>>>flip (++) "hello" "world""worldhello"
Kinds
data Constraint #
The kind of constraints, like Show a
First Class Families
type family Eval (e :: Exp a) :: a #
Expression evaluator.
Instances
| type Eval (Not 'False) | |
Defined in Fcf.Data.Bool | |
| type Eval (Not 'True) | |
Defined in Fcf.Data.Bool | |
| type Eval (Constraints (a ': as) :: Constraint -> Type) | |
Defined in Fcf.Utils | |
| type Eval (Constraints ('[] :: [Constraint])) | |
Defined in Fcf.Utils | |
| type Eval (MEmpty_ :: a -> Type) | |
Defined in Fcf.Class.Monoid | |
| type Eval (Null (a2 ': as) :: Bool -> Type) | |
| type Eval (Null ('[] :: [a]) :: Bool -> Type) | |
| type Eval (And lst :: Bool -> Type) | |
| type Eval (Or lst :: Bool -> Type) | |
| type Eval (a <= b :: Bool -> Type) | |
| type Eval (a >= b :: Bool -> Type) | |
| type Eval (a < b :: Bool -> Type) | |
| type Eval (a > b :: Bool -> Type) | |
| type Eval (IsNothing ('Nothing :: Maybe a) :: Bool -> Type) | |
| type Eval (IsNothing ('Just _a) :: Bool -> Type) | |
| type Eval (IsJust ('Nothing :: Maybe a) :: Bool -> Type) | |
| type Eval (IsJust ('Just _a) :: Bool -> Type) | |
| type Eval ('False || b :: Bool -> Type) | |
| type Eval ('True || b :: Bool -> Type) | |
| type Eval (a || 'False :: Bool -> Type) | |
| type Eval (a || 'True :: Bool -> Type) | |
| type Eval ('False && b :: Bool -> Type) | |
| type Eval ('True && b :: Bool -> Type) | |
| type Eval (a && 'True :: Bool -> Type) | |
| type Eval (a && 'False :: Bool -> Type) | |
| type Eval (Length (a2 ': as) :: Nat -> Type) | |
| type Eval (Length ('[] :: [a]) :: Nat -> Type) | |
Defined in Fcf.Data.List | |
| type Eval (Sum ns :: Nat -> Type) | |
| type Eval (a + b :: Nat -> Type) | |
| type Eval (a - b :: Nat -> Type) | |
| type Eval (a * b :: Nat -> Type) | |
| type Eval (a ^ b :: Nat -> Type) | |
| type Eval (Error msg :: a -> Type) | |
| type Eval (TError msg :: a -> Type) | |
| type Eval (Pure x :: a -> Type) | |
Defined in Fcf.Combinators | |
| type Eval (Join e :: a -> Type) | |
| type Eval (IsPrefixOf xs ys :: Bool -> Type) | |
Defined in Fcf.Data.List | |
| type Eval (IsSuffixOf xs ys :: Bool -> Type) | |
Defined in Fcf.Data.List | |
| type Eval (IsInfixOf xs ys :: Bool -> Type) | |
| type Eval (Elem a2 as :: Bool -> Type) | |
| type Eval (IsLeft ('Right _a :: Either a b) :: Bool -> Type) | |
| type Eval (IsLeft ('Left _a :: Either a b) :: Bool -> Type) | |
| type Eval (IsRight ('Right _a :: Either a b) :: Bool -> Type) | |
| type Eval (IsRight ('Left _a :: Either a b) :: Bool -> Type) | |
| type Eval (Fst '(a2, _b) :: a1 -> Type) | |
Defined in Fcf.Data.Common | |
| type Eval (Snd '(_a, b) :: a2 -> Type) | |
Defined in Fcf.Data.Common | |
| type Eval (FromMaybe _a ('Just b) :: a -> Type) | |
Defined in Fcf.Data.Common | |
| type Eval (FromMaybe a2 ('Nothing :: Maybe a1) :: a1 -> Type) | |
| type Eval (x .<> y :: a -> Type) | |
Defined in Fcf.Class.Monoid | |
| type Eval (Concat xs :: a -> Type) | |
| type Eval (TyEq a b :: Bool -> Type) | |
| type Eval (All p lst :: Bool -> Type) | |
| type Eval (Any p lst :: Bool -> Type) | |
| type Eval (Case ms a :: k -> Type) | |
| type Eval (x & f :: a2 -> Type) | |
Defined in Fcf.Data.Function | |
| type Eval (UnBool fal tru 'True :: a -> Type) | |
| type Eval (UnBool fal tru 'False :: a -> Type) | |
| type Eval (Pure1 f x :: a2 -> Type) | |
Defined in Fcf.Combinators | |
| type Eval (k =<< e :: a2 -> Type) | |
| type Eval (e >>= k :: a2 -> Type) | |
Defined in Fcf.Combinators | |
| type Eval (f <$> e :: a2 -> Type) | |
Defined in Fcf.Combinators | |
| type Eval (f <*> e :: a2 -> Type) | |
| type Eval (ConstFn a2 _b :: a1 -> Type) | |
Defined in Fcf.Combinators | |
| type Eval (f $ a3 :: a2 -> Type) | |
Defined in Fcf.Combinators | |
| type Eval (UnList y f xs :: a1 -> Type) | |
| type Eval (Uncurry f '(x, y) :: a2 -> Type) | |
Defined in Fcf.Data.Common | |
| type Eval (UnMaybe y f ('Just x) :: a1 -> Type) | |
| type Eval (UnMaybe y f ('Nothing :: Maybe a2) :: a1 -> Type) | |
| type Eval (FoldMap f ('Right x :: Either a3 a1) :: a2 -> Type) | |
| type Eval (FoldMap f ('Left _a :: Either a3 a1) :: a2 -> Type) | |
| type Eval (FoldMap f ('Just x) :: a2 -> Type) | |
| type Eval (FoldMap f ('Nothing :: Maybe a1) :: a2 -> Type) | |
| type Eval (FoldMap f (x ': xs) :: a2 -> Type) | |
| type Eval (FoldMap f ('[] :: [a1]) :: a2 -> Type) | |
Defined in Fcf.Class.Foldable | |
| type Eval (UnEither f g ('Right y :: Either a1 b) :: a2 -> Type) | |
| type Eval (UnEither f g ('Left x :: Either a1 b) :: a2 -> Type) | |
| type Eval (Pure2 f x y :: a2 -> Type) | |
Defined in Fcf.Combinators | |
| type Eval ((f <=< g) x :: a2 -> Type) | |
| type Eval (LiftM2 f x y :: a3 -> Type) | |
| type Eval (Flip f y x :: a2 -> Type) | |
Defined in Fcf.Combinators | |
| type Eval (Foldr f y ('Right x :: Either a3 a1) :: a2 -> Type) | |
| type Eval (Foldr f y ('Left _a :: Either a3 a1) :: a2 -> Type) | |
| type Eval (Foldr f y ('Just x) :: a2 -> Type) | |
| type Eval (Foldr f y ('Nothing :: Maybe a1) :: a2 -> Type) | |
| type Eval (Foldr f y (x ': xs) :: a2 -> Type) | |
| type Eval (Foldr f y ('[] :: [a1]) :: a2 -> Type) | |
Defined in Fcf.Class.Foldable | |
| type Eval (On r f x y :: a2 -> Type) | |
| type Eval (Pure3 f x y z :: a2 -> Type) | |
Defined in Fcf.Combinators | |
| type Eval (LiftM3 f x y z :: a4 -> Type) | |
| type Eval (Bicomap f g r x y :: a4 -> Type) | |
| type Eval (Tails (a2 ': as) :: [[a1]] -> Type) | |
| type Eval (Tails ('[] :: [a]) :: [[a]] -> Type) | |
Defined in Fcf.Data.List | |
| type Eval (Reverse l :: [a] -> Type) | |
Defined in Fcf.Data.List | |
| type Eval (Init '[a2] :: Maybe [a1] -> Type) | |
| type Eval (Init ('[] :: [a]) :: Maybe [a] -> Type) | |
| type Eval (Tail (_a ': as) :: Maybe [a] -> Type) | |
| type Eval (Tail ('[] :: [a]) :: Maybe [a] -> Type) | |
| type Eval (Init (a2 ': (b ': as)) :: Maybe [a1] -> Type) | |
| type Eval (Head (a2 ': _as) :: Maybe a1 -> Type) | |
| type Eval (Head ('[] :: [a]) :: Maybe a -> Type) | |
| type Eval (Last (a2 ': (b ': as)) :: Maybe a1 -> Type) | |
| type Eval (Last '[a2] :: Maybe a1 -> Type) | |
| type Eval (Last ('[] :: [a]) :: Maybe a -> Type) | |
| type Eval (xs ++ ys :: [a] -> Type) | |
Defined in Fcf.Data.List | |
| type Eval (Cons a2 as :: [a1] -> Type) | |
Defined in Fcf.Data.List | |
| type Eval (Snoc lst a :: [k] -> Type) | |
| type Eval (Rev (x ': xs) ys :: [a] -> Type) | |
Defined in Fcf.Data.List | |
| type Eval (Rev ('[] :: [a]) ys :: [a] -> Type) | |
Defined in Fcf.Data.List | |
| type Eval (Intersperse _1 ('[] :: [a]) :: [a] -> Type) | |
Defined in Fcf.Data.List | |
| type Eval (PrependToAll sep (x ': xs) :: [a] -> Type) | |
Defined in Fcf.Data.List | |
| type Eval (PrependToAll _1 ('[] :: [a]) :: [a] -> Type) | |
Defined in Fcf.Data.List | |
| type Eval (Intersperse sep (x ': xs) :: [a] -> Type) | |
Defined in Fcf.Data.List | |
| type Eval (Intercalate xs xss :: [a] -> Type) | |
Defined in Fcf.Data.List type Eval (Intercalate xs xss :: [a] -> Type) = Eval ((Concat :: [[a]] -> [a] -> Type) =<< Intersperse xs xss) | |
| type Eval (Replicate n a2 :: [a1] -> Type) | |
| type Eval (Take n as :: [a] -> Type) | |
Defined in Fcf.Data.List | |
| type Eval (Drop n as :: [a] -> Type) | |
Defined in Fcf.Data.List | |
| type Eval (TakeWhile p (x ': xs) :: [a] -> Type) | |
| type Eval (TakeWhile p ('[] :: [a]) :: [a] -> Type) | |
Defined in Fcf.Data.List | |
| type Eval (DropWhile p (x ': xs) :: [a] -> Type) | |
| type Eval (DropWhile p ('[] :: [a]) :: [a] -> Type) | |
Defined in Fcf.Data.List | |
| type Eval (Filter p (a2 ': as) :: [a1] -> Type) | |
| type Eval (Filter _p ('[] :: [a]) :: [a] -> Type) | |
Defined in Fcf.Data.List | |
| type Eval (FindIndex p (a2 ': as) :: Maybe Nat -> Type) | |
| type Eval (FindIndex _p ('[] :: [a]) :: Maybe Nat -> Type) | |
| type Eval (NumIter a s :: Maybe (k, Nat) -> Type) | |
| type Eval (Find p (a2 ': as) :: Maybe a1 -> Type) | |
| type Eval (Find _p ('[] :: [a]) :: Maybe a -> Type) | |
| type Eval (Zip as bs :: [(a, b)] -> Type) | |
| type Eval (UnfoldrCase _1 ('Nothing :: Maybe (a, b)) :: [a] -> Type) | |
Defined in Fcf.Data.List | |
| type Eval (Unfoldr f c :: [a] -> Type) | |
| type Eval (UnfoldrCase f ('Just ab) :: [a2] -> Type) | |
| type Eval (SetIndex n a' as :: [k] -> Type) | |
Defined in Fcf.Data.List | |
| type Eval (Lookup a as :: Maybe b -> Type) | |
| type Eval (ConcatMap f xs :: [b] -> Type) | |
| type Eval (Map f (a2 ': as) :: [b] -> Type) | |
| type Eval (Map f ('[] :: [a]) :: [b] -> Type) | |
Defined in Fcf.Class.Functor | |
| type Eval (Map f ('Just a3) :: Maybe a2 -> Type) | |
| type Eval (Map f ('Nothing :: Maybe a) :: Maybe b -> Type) | |
| type Eval (ZipWith f (a2 ': as) (b2 ': bs) :: [c] -> Type) | |
| type Eval (ZipWith _f _as ('[] :: [b]) :: [c] -> Type) | |
Defined in Fcf.Data.List | |
| type Eval (ZipWith _f ('[] :: [a]) _bs :: [c] -> Type) | |
Defined in Fcf.Data.List | |
| type Eval (Span p lst :: ([a], [a]) -> Type) | |
| type Eval (Break p lst :: ([a], [a]) -> Type) | |
| type Eval (Partition p lst :: ([a], [a]) -> Type) | |
| type Eval (Unzip as :: ([a], [b]) -> Type) | |
| type Eval (Cons2 '(a3, b) '(as, bs) :: ([a1], [a2]) -> Type) | |
Defined in Fcf.Data.List | |
| type Eval (PartHelp p a2 '(xs, ys) :: ([a1], [a1]) -> Type) | |
Defined in Fcf.Data.List | |
| type Eval (Map f ('Right a3 :: Either a2 a1) :: Either a2 b -> Type) | |
| type Eval (Map f ('Left x :: Either a2 a1) :: Either a2 b -> Type) | |
| type Eval (Map f '(x, a2) :: (k2, k1) -> Type) | |
Defined in Fcf.Class.Functor | |
| type Eval ((f *** f') '(b2, b'2) :: (k1, k2) -> Type) | |
| type Eval (First f2 x :: f1 a' b' -> Type) | |
| type Eval (Second g x :: f a' b' -> Type) | |
| type Eval (Bimap f g ('Right y :: Either a b1) :: Either a' b2 -> Type) | |
| type Eval (Bimap f g ('Left x :: Either a1 b) :: Either a2 b' -> Type) | |
| type Eval (Bimap f g '(x, y) :: (k1, k2) -> Type) | |
| type Eval (Map f '(x, y, a2) :: (k2, k3, k1) -> Type) | |
Defined in Fcf.Class.Functor | |
| type Eval (Map f '(x, y, z, a2) :: (k2, k3, k4, k1) -> Type) | |
Defined in Fcf.Class.Functor | |
| type Eval (Map f '(x, y, z, w, a2) :: (k2, k3, k4, k5, k1) -> Type) | |
Defined in Fcf.Class.Functor | |
Exceptions
class (Typeable e, Show e) => Exception e where #
Any type that you wish to throw or catch as an exception must be an
instance of the Exception class. The simplest case is a new exception
type directly below the root:
data MyException = ThisException | ThatException
deriving Show
instance Exception MyExceptionThe 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 = frontendExceptionFromExceptionWe can now catch a MismatchedParentheses exception as
MismatchedParentheses, SomeFrontendException or
SomeCompilerException, but not other types, e.g. IOException:
*Main> throw MismatchedParentheses `catch` \e -> putStrLn ("Caught " ++ show (e :: MismatchedParentheses))
Caught MismatchedParentheses
*Main> throw MismatchedParentheses `catch` \e -> putStrLn ("Caught " ++ show (e :: SomeFrontendException))
Caught MismatchedParentheses
*Main> throw MismatchedParentheses `catch` \e -> putStrLn ("Caught " ++ show (e :: SomeCompilerException))
Caught MismatchedParentheses
*Main> throw MismatchedParentheses `catch` \e -> putStrLn ("Caught " ++ show (e :: IOException))
*** Exception: MismatchedParentheses
Minimal complete definition
Nothing
Methods
displayException :: e -> String #
Render this exception value in a human-friendly manner.
Default implementation: .show
Since: base-4.8.0.0
Instances
data SomeException #
The SomeException type is the root of the exception type hierarchy.
When an exception of type e is thrown, behind the scenes it is
encapsulated in a SomeException.
Instances
| Show SomeException | Since: base-3.0 |
Defined in GHC.Exception.Type Methods showsPrec :: Int -> SomeException -> ShowS # show :: SomeException -> String # showList :: [SomeException] -> ShowS # | |
| Exception SomeException | Since: base-3.0 |
Defined in GHC.Exception.Type Methods toException :: SomeException -> SomeException # fromException :: SomeException -> Maybe SomeException # displayException :: SomeException -> String # | |