ghc-internal-9.1001.0: Basic libraries
Copyright(c) The University of Glasgow 1992-2002
Licensesee libraries/base/LICENSE
Maintainerghc-devs@haskell.org
Stabilityinternal
Portabilitynon-portable (GHC extensions)
Safe HaskellUnsafe
LanguageHaskell2010

GHC.Internal.Base

Description

Basic data types and classes.

Synopsis

Documentation

type String = [Char] Source #

String is an alias for a list of characters.

String constants in Haskell are values of type String. That means if you write a string literal like "hello world", it will have the type [Char], which is the same as String.

Note: You can ask the compiler to automatically infer different types with the -XOverloadedStrings language extension, for example "hello world" :: Text. See IsString for more information.

Because String is just a list of characters, you can use normal list functions to do basic string manipulation. See Data.List for operations on lists.

Performance considerations

Expand

[Char] is a relatively memory-inefficient type. It is a linked list of boxed word-size characters, internally it looks something like:

╭─────┬───┬──╮  ╭─────┬───┬──╮  ╭─────┬───┬──╮  ╭────╮
│ (:) │   │ ─┼─>│ (:) │   │ ─┼─>│ (:) │   │ ─┼─>│ [] │
╰─────┴─┼─┴──╯  ╰─────┴─┼─┴──╯  ╰─────┴─┼─┴──╯  ╰────╯
        v               v               v
       'a'             'b'             'c'

The String "abc" will use 5*3+1 = 16 (in general 5n+1) words of space in memory.

Furthermore, operations like (++) (string concatenation) are O(n) (in the left argument).

For historical reasons, the base library uses String in a lot of places for the conceptual simplicity, but library code dealing with user-data should use the text package for Unicode text, or the the bytestring package for binary data.

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

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

Instances of Monad should satisfy the following:

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

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

The above laws imply:

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

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

Minimal complete definition

(>>=)

Methods

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

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

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

do a <- as
   bs a

An alternative name for this function is 'bind', but some people may refer to it as 'flatMap', which results from it being equivialent to

\x f -> join (fmap f x) :: Monad m => m a -> (a -> m b) -> m b

which can be seen as mapping a value with Monad m => m a -> m (m b) and then 'flattening' m (m b) to m b using join.

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

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

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

do as
   bs

or in terms of (>>=) as

as >>= const bs

return :: a -> m a Source #

Inject a value into the monadic type. This function should not be different from its default implementation as pure. The justification for the existence of this function is merely historic.

Instances

Instances details
Monad NonEmpty Source #

@since base-4.9.0.0

Instance details

Defined in GHC.Internal.Base

Methods

(>>=) :: NonEmpty a -> (a -> NonEmpty b) -> NonEmpty b Source #

(>>) :: NonEmpty a -> NonEmpty b -> NonEmpty b Source #

return :: a -> NonEmpty a Source #

Monad STM Source #

@since base-4.3.0.0

Instance details

Defined in GHC.Internal.Conc.Sync

Methods

(>>=) :: STM a -> (a -> STM b) -> STM b Source #

(>>) :: STM a -> STM b -> STM b Source #

return :: a -> STM a Source #

Monad Identity Source #

@since base-4.8.0.0

Instance details

Defined in GHC.Internal.Data.Functor.Identity

Methods

(>>=) :: Identity a -> (a -> Identity b) -> Identity b Source #

(>>) :: Identity a -> Identity b -> Identity b Source #

return :: a -> Identity a Source #

Monad First Source #

@since base-4.8.0.0

Instance details

Defined in GHC.Internal.Data.Monoid

Methods

(>>=) :: First a -> (a -> First b) -> First b Source #

(>>) :: First a -> First b -> First b Source #

return :: a -> First a Source #

Monad Last Source #

@since base-4.8.0.0

Instance details

Defined in GHC.Internal.Data.Monoid

Methods

(>>=) :: Last a -> (a -> Last b) -> Last b Source #

(>>) :: Last a -> Last b -> Last b Source #

return :: a -> Last a Source #

Monad Down Source #

@since base-4.11.0.0

Instance details

Defined in GHC.Internal.Data.Ord

Methods

(>>=) :: Down a -> (a -> Down b) -> Down b Source #

(>>) :: Down a -> Down b -> Down b Source #

return :: a -> Down a Source #

Monad Dual Source #

@since base-4.8.0.0

Instance details

Defined in GHC.Internal.Data.Semigroup.Internal

Methods

(>>=) :: Dual a -> (a -> Dual b) -> Dual b Source #

(>>) :: Dual a -> Dual b -> Dual b Source #

return :: a -> Dual a Source #

Monad Product Source #

@since base-4.8.0.0

Instance details

Defined in GHC.Internal.Data.Semigroup.Internal

Methods

(>>=) :: Product a -> (a -> Product b) -> Product b Source #

(>>) :: Product a -> Product b -> Product b Source #

return :: a -> Product a Source #

Monad Sum Source #

@since base-4.8.0.0

Instance details

Defined in GHC.Internal.Data.Semigroup.Internal

Methods

(>>=) :: Sum a -> (a -> Sum b) -> Sum b Source #

(>>) :: Sum a -> Sum b -> Sum b Source #

return :: a -> Sum a Source #

Monad NoIO Source #

@since base-4.4.0.0

Instance details

Defined in GHC.Internal.GHCi

Methods

(>>=) :: NoIO a -> (a -> NoIO b) -> NoIO b Source #

(>>) :: NoIO a -> NoIO b -> NoIO b Source #

return :: a -> NoIO a Source #

Monad Par1 Source #

@since base-4.9.0.0

Instance details

Defined in GHC.Internal.Generics

Methods

(>>=) :: Par1 a -> (a -> Par1 b) -> Par1 b Source #

(>>) :: Par1 a -> Par1 b -> Par1 b Source #

return :: a -> Par1 a Source #

Monad ReadP Source #

@since base-2.01

Instance details

Defined in GHC.Internal.Text.ParserCombinators.ReadP

Methods

(>>=) :: ReadP a -> (a -> ReadP b) -> ReadP b Source #

(>>) :: ReadP a -> ReadP b -> ReadP b Source #

return :: a -> ReadP a Source #

Monad ReadPrec Source #

@since base-2.01

Instance details

Defined in GHC.Internal.Text.ParserCombinators.ReadPrec

Methods

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

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

return :: a -> ReadPrec a Source #

Monad IO Source #

@since base-2.01

Instance details

Defined in GHC.Internal.Base

Methods

(>>=) :: IO a -> (a -> IO b) -> IO b Source #

(>>) :: IO a -> IO b -> IO b Source #

return :: a -> IO a Source #

Monad Maybe Source #

@since base-2.01

Instance details

Defined in GHC.Internal.Base

Methods

(>>=) :: Maybe a -> (a -> Maybe b) -> Maybe b Source #

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

return :: a -> Maybe a Source #

Monad Solo Source #

@since base-4.15

Instance details

Defined in GHC.Internal.Base

Methods

(>>=) :: Solo a -> (a -> Solo b) -> Solo b Source #

(>>) :: Solo a -> Solo b -> Solo b Source #

return :: a -> Solo a Source #

Monad [] Source #

@since base-2.01

Instance details

Defined in GHC.Internal.Base

Methods

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

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

return :: a -> [a] Source #

ArrowApply a => Monad (ArrowMonad a) Source #

@since base-2.01

Instance details

Defined in GHC.Internal.Control.Arrow

Methods

(>>=) :: ArrowMonad a a0 -> (a0 -> ArrowMonad a b) -> ArrowMonad a b Source #

(>>) :: ArrowMonad a a0 -> ArrowMonad a b -> ArrowMonad a b Source #

return :: a0 -> ArrowMonad a a0 Source #

Monad (ST s) Source #

@since base-2.01

Instance details

Defined in GHC.Internal.Control.Monad.ST.Lazy.Imp

Methods

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

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

return :: a -> ST s a Source #

Monad (Either e) Source #

@since base-4.4.0.0

Instance details

Defined in GHC.Internal.Data.Either

Methods

(>>=) :: Either e a -> (a -> Either e b) -> Either e b Source #

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

return :: a -> Either e a Source #

Monad (Proxy :: Type -> Type) Source #

@since base-4.7.0.0

Instance details

Defined in GHC.Internal.Data.Proxy

Methods

(>>=) :: Proxy a -> (a -> Proxy b) -> Proxy b Source #

(>>) :: Proxy a -> Proxy b -> Proxy b Source #

return :: a -> Proxy a Source #

Monad (U1 :: Type -> Type) Source #

@since base-4.9.0.0

Instance details

Defined in GHC.Internal.Generics

Methods

(>>=) :: U1 a -> (a -> U1 b) -> U1 b Source #

(>>) :: U1 a -> U1 b -> U1 b Source #

return :: a -> U1 a Source #

Monad (ST s) Source #

@since base-2.01

Instance details

Defined in GHC.Internal.ST

Methods

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

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

return :: a -> ST s a Source #

Monoid a => Monad ((,) a) Source #

@since base-4.9.0.0

Instance details

Defined in GHC.Internal.Base

Methods

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

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

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

Monad m => Monad (Kleisli m a) Source #

@since base-4.14.0.0

Instance details

Defined in GHC.Internal.Control.Arrow

Methods

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

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

return :: a0 -> Kleisli m a a0 Source #

Monad m => Monad (StateT s m) Source #

@since base-4.18.0.0

Instance details

Defined in GHC.Internal.Data.Functor.Utils

Methods

(>>=) :: StateT s m a -> (a -> StateT s m b) -> StateT s m b Source #

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

return :: a -> StateT s m a Source #

Monad f => Monad (Ap f) Source #

@since base-4.12.0.0

Instance details

Defined in GHC.Internal.Data.Monoid

Methods

(>>=) :: Ap f a -> (a -> Ap f b) -> Ap f b Source #

(>>) :: Ap f a -> Ap f b -> Ap f b Source #

return :: a -> Ap f a Source #

Monad f => Monad (Alt f) Source #

@since base-4.8.0.0

Instance details

Defined in GHC.Internal.Data.Semigroup.Internal

Methods

(>>=) :: Alt f a -> (a -> Alt f b) -> Alt f b Source #

(>>) :: Alt f a -> Alt f b -> Alt f b Source #

return :: a -> Alt f a Source #

Monad f => Monad (Rec1 f) Source #

@since base-4.9.0.0

Instance details

Defined in GHC.Internal.Generics

Methods

(>>=) :: Rec1 f a -> (a -> Rec1 f b) -> Rec1 f b Source #

(>>) :: Rec1 f a -> Rec1 f b -> Rec1 f b Source #

return :: a -> Rec1 f a Source #

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

@since base-4.14.0.0

Instance details

Defined in GHC.Internal.Base

Methods

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

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

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

(Monad f, Monad g) => Monad (f :*: g) Source #

@since base-4.9.0.0

Instance details

Defined in GHC.Internal.Generics

Methods

(>>=) :: (f :*: g) a -> (a -> (f :*: g) b) -> (f :*: g) b Source #

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

return :: a -> (f :*: g) a Source #

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

@since base-4.14.0.0

Instance details

Defined in GHC.Internal.Base

Methods

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

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

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

Monad ((->) r) Source #

@since base-2.01

Instance details

Defined in GHC.Internal.Base

Methods

(>>=) :: (r -> a) -> (a -> r -> b) -> r -> b Source #

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

return :: a -> r -> a Source #

Monad f => Monad (M1 i c f) Source #

@since base-4.9.0.0

Instance details

Defined in GHC.Internal.Generics

Methods

(>>=) :: M1 i c f a -> (a -> M1 i c f b) -> M1 i c f b Source #

(>>) :: M1 i c f a -> M1 i c f b -> M1 i c f b Source #

return :: a -> M1 i c f a Source #

(.) :: (b -> c) -> (a -> b) -> a -> c infixr 9 Source #

Right to left function composition.

(f . g) x = f (g x)
f . id = f = id . f

Examples

Expand
>>> map ((*2) . length) [[], [0, 1, 2], [0]]
[0,6,2]
>>> foldr (.) id [(+1), (*3), (^3)] 2
25
>>> let (...) = (.).(.) in ((*2)...(+)) 5 10
30

id :: a -> a Source #

Identity function.

id x = x

This function might seem useless at first glance, but it can be very useful in a higher order context.

Examples

Expand
>>> length $ filter id [True, True, False, True]
3
>>> Just (Just 3) >>= id
Just 3
>>> foldr id 0 [(^3), (*5), (+2)]
1000

assert :: Bool -> a -> a Source #

If the first argument evaluates to True, then the result is the second argument. Otherwise an AssertionFailed exception is raised, containing a String with the source file and line number of the call to assert.

Assertions can normally be turned on or off with a compiler flag (for GHC, assertions are normally on unless optimisation is turned on with -O or the -fignore-asserts option is given). When assertions are turned off, the first argument to assert is ignored, and the second argument is returned as the result.

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

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

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

Note, that the second law follows from the free theorem of the type fmap and the first law, so you need only check that the former condition holds. See these articles by School of Haskell or David Luposchainsky for an explanation.

Minimal complete definition

fmap

Methods

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

fmap is used to apply a function of type (a -> b) to a value of type f a, where f is a functor, to produce a value of type f b. Note that for any type constructor with more than one parameter (e.g., Either), only the last type parameter can be modified with fmap (e.g., b in `Either a b`).

Some type constructors with two parameters or more have a Bifunctor instance that allows both the last and the penultimate parameters to be mapped over.

Examples

Expand

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

>>> fmap show Nothing
Nothing
>>> fmap show (Just 3)
Just "3"

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

>>> fmap show (Left 17)
Left 17
>>> fmap show (Right 17)
Right "17"

Double each element of a list:

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

Apply even to the second element of a pair:

>>> fmap even (2,2)
(2,True)

It may seem surprising that the function is only applied to the last element of the tuple compared to the list example above which applies it to every element in the list. To understand, remember that tuples are type constructors with multiple type parameters: a tuple of 3 elements (a,b,c) can also be written (,,) a b c and its Functor instance is defined for Functor ((,,) a b) (i.e., only the third parameter is free to be mapped over with fmap).

It explains why fmap can be used with tuples containing values of different types as in the following example:

>>> fmap even ("hello", 1.0, 4)
("hello",1.0,True)

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

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

Examples

Expand

Perform a computation with Maybe and replace the result with a constant value if it is Just:

>>> 'a' <$ Just 2
Just 'a'
>>> 'a' <$ Nothing
Nothing

Instances

Instances details
Functor NonEmpty Source #

@since base-4.9.0.0

Instance details

Defined in GHC.Internal.Base

Methods

fmap :: (a -> b) -> NonEmpty a -> NonEmpty b Source #

(<$) :: a -> NonEmpty b -> NonEmpty a Source #

Functor STM Source #

@since base-4.3.0.0

Instance details

Defined in GHC.Internal.Conc.Sync

Methods

fmap :: (a -> b) -> STM a -> STM b Source #

(<$) :: a -> STM b -> STM a Source #

Functor Handler Source #

@since base-4.6.0.0

Instance details

Defined in GHC.Internal.Control.Exception

Methods

fmap :: (a -> b) -> Handler a -> Handler b Source #

(<$) :: a -> Handler b -> Handler a Source #

Functor Identity Source #

@since base-4.8.0.0

Instance details

Defined in GHC.Internal.Data.Functor.Identity

Methods

fmap :: (a -> b) -> Identity a -> Identity b Source #

(<$) :: a -> Identity b -> Identity a Source #

Functor First Source #

@since base-4.8.0.0

Instance details

Defined in GHC.Internal.Data.Monoid

Methods

fmap :: (a -> b) -> First a -> First b Source #

(<$) :: a -> First b -> First a Source #

Functor Last Source #

@since base-4.8.0.0

Instance details

Defined in GHC.Internal.Data.Monoid

Methods

fmap :: (a -> b) -> Last a -> Last b Source #

(<$) :: a -> Last b -> Last a Source #

Functor Down Source #

@since base-4.11.0.0

Instance details

Defined in GHC.Internal.Data.Ord

Methods

fmap :: (a -> b) -> Down a -> Down b Source #

(<$) :: a -> Down b -> Down a Source #

Functor Dual Source #

@since base-4.8.0.0

Instance details

Defined in GHC.Internal.Data.Semigroup.Internal

Methods

fmap :: (a -> b) -> Dual a -> Dual b Source #

(<$) :: a -> Dual b -> Dual a Source #

Functor Product Source #

@since base-4.8.0.0

Instance details

Defined in GHC.Internal.Data.Semigroup.Internal

Methods

fmap :: (a -> b) -> Product a -> Product b Source #

(<$) :: a -> Product b -> Product a Source #

Functor Sum Source #

@since base-4.8.0.0

Instance details

Defined in GHC.Internal.Data.Semigroup.Internal

Methods

fmap :: (a -> b) -> Sum a -> Sum b Source #

(<$) :: a -> Sum b -> Sum a Source #

Functor ZipList Source #

@since base-2.01

Instance details

Defined in GHC.Internal.Functor.ZipList

Methods

fmap :: (a -> b) -> ZipList a -> ZipList b Source #

(<$) :: a -> ZipList b -> ZipList a Source #

Functor NoIO Source #

@since base-4.8.0.0

Instance details

Defined in GHC.Internal.GHCi

Methods

fmap :: (a -> b) -> NoIO a -> NoIO b Source #

(<$) :: a -> NoIO b -> NoIO a Source #

Functor Par1 Source #

@since base-4.9.0.0

Instance details

Defined in GHC.Internal.Generics

Methods

fmap :: (a -> b) -> Par1 a -> Par1 b Source #

(<$) :: a -> Par1 b -> Par1 a Source #

Functor ReadP Source #

@since base-2.01

Instance details

Defined in GHC.Internal.Text.ParserCombinators.ReadP

Methods

fmap :: (a -> b) -> ReadP a -> ReadP b Source #

(<$) :: a -> ReadP b -> ReadP a Source #

Functor ReadPrec Source #

@since base-2.01

Instance details

Defined in GHC.Internal.Text.ParserCombinators.ReadPrec

Methods

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

(<$) :: a -> ReadPrec b -> ReadPrec a Source #

Functor IO Source #

@since base-2.01

Instance details

Defined in GHC.Internal.Base

Methods

fmap :: (a -> b) -> IO a -> IO b Source #

(<$) :: a -> IO b -> IO a Source #

Functor Maybe Source #

@since base-2.01

Instance details

Defined in GHC.Internal.Base

Methods

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

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

Functor Solo Source #

@since base-4.15

Instance details

Defined in GHC.Internal.Base

Methods

fmap :: (a -> b) -> Solo a -> Solo b Source #

(<$) :: a -> Solo b -> Solo a Source #

Functor [] Source #

@since base-2.01

Instance details

Defined in GHC.Internal.Base

Methods

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

(<$) :: a -> [b] -> [a] Source #

Functor (Array i) Source #

@since base-2.01

Instance details

Defined in GHC.Internal.Arr

Methods

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

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

Arrow a => Functor (ArrowMonad a) Source #

@since base-4.6.0.0

Instance details

Defined in GHC.Internal.Control.Arrow

Methods

fmap :: (a0 -> b) -> ArrowMonad a a0 -> ArrowMonad a b Source #

(<$) :: a0 -> ArrowMonad a b -> ArrowMonad a a0 Source #

Functor (ST s) Source #

@since base-2.01

Instance details

Defined in GHC.Internal.Control.Monad.ST.Lazy.Imp

Methods

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

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

Functor (Either a) Source #

@since base-3.0

Instance details

Defined in GHC.Internal.Data.Either

Methods

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

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

Functor (StateL s) Source #

@since base-4.0

Instance details

Defined in GHC.Internal.Data.Functor.Utils

Methods

fmap :: (a -> b) -> StateL s a -> StateL s b Source #

(<$) :: a -> StateL s b -> StateL s a Source #

Functor (StateR s) Source #

@since base-4.0

Instance details

Defined in GHC.Internal.Data.Functor.Utils

Methods

fmap :: (a -> b) -> StateR s a -> StateR s b Source #

(<$) :: a -> StateR s b -> StateR s a Source #

Functor (Proxy :: Type -> Type) Source #

@since base-4.7.0.0

Instance details

Defined in GHC.Internal.Data.Proxy

Methods

fmap :: (a -> b) -> Proxy a -> Proxy b Source #

(<$) :: a -> Proxy b -> Proxy a Source #

Functor (U1 :: Type -> Type) Source #

@since base-4.9.0.0

Instance details

Defined in GHC.Internal.Generics

Methods

fmap :: (a -> b) -> U1 a -> U1 b Source #

(<$) :: a -> U1 b -> U1 a Source #

Functor (V1 :: Type -> Type) Source #

@since base-4.9.0.0

Instance details

Defined in GHC.Internal.Generics

Methods

fmap :: (a -> b) -> V1 a -> V1 b Source #

(<$) :: a -> V1 b -> V1 a Source #

Functor (ST s) Source #

@since base-2.01

Instance details

Defined in GHC.Internal.ST

Methods

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

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

Functor ((,) a) Source #

@since base-2.01

Instance details

Defined in GHC.Internal.Base

Methods

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

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

Functor m => Functor (Kleisli m a) Source #

@since base-4.14.0.0

Instance details

Defined in GHC.Internal.Control.Arrow

Methods

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

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

Functor (Const m :: Type -> Type) Source #

@since base-2.01

Instance details

Defined in GHC.Internal.Data.Functor.Const

Methods

fmap :: (a -> b) -> Const m a -> Const m b Source #

(<$) :: a -> Const m b -> Const m a Source #

Monad m => Functor (StateT s m) Source #

@since base-4.18.0.0

Instance details

Defined in GHC.Internal.Data.Functor.Utils

Methods

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

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

Functor f => Functor (Ap f) Source #

@since base-4.12.0.0

Instance details

Defined in GHC.Internal.Data.Monoid

Methods

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

(<$) :: a -> Ap f b -> Ap f a Source #

Functor f => Functor (Alt f) Source #

@since base-4.8.0.0

Instance details

Defined in GHC.Internal.Data.Semigroup.Internal

Methods

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

(<$) :: a -> Alt f b -> Alt f a Source #

(Generic1 f, Functor (Rep1 f)) => Functor (Generically1 f) Source #

@since base-4.17.0.0

Instance details

Defined in GHC.Internal.Generics

Methods

fmap :: (a -> b) -> Generically1 f a -> Generically1 f b Source #

(<$) :: a -> Generically1 f b -> Generically1 f a Source #

Functor f => Functor (Rec1 f) Source #

@since base-4.9.0.0

Instance details

Defined in GHC.Internal.Generics

Methods

fmap :: (a -> b) -> Rec1 f a -> Rec1 f b Source #

(<$) :: a -> Rec1 f b -> Rec1 f a Source #

Functor (URec (Ptr ()) :: Type -> Type) Source #

@since base-4.9.0.0

Instance details

Defined in GHC.Internal.Generics

Methods

fmap :: (a -> b) -> URec (Ptr ()) a -> URec (Ptr ()) b Source #

(<$) :: a -> URec (Ptr ()) b -> URec (Ptr ()) a Source #

Functor (URec Char :: Type -> Type) Source #

@since base-4.9.0.0

Instance details

Defined in GHC.Internal.Generics

Methods

fmap :: (a -> b) -> URec Char a -> URec Char b Source #

(<$) :: a -> URec Char b -> URec Char a Source #

Functor (URec Double :: Type -> Type) Source #

@since base-4.9.0.0

Instance details

Defined in GHC.Internal.Generics

Methods

fmap :: (a -> b) -> URec Double a -> URec Double b Source #

(<$) :: a -> URec Double b -> URec Double a Source #

Functor (URec Float :: Type -> Type) Source #

@since base-4.9.0.0

Instance details

Defined in GHC.Internal.Generics

Methods

fmap :: (a -> b) -> URec Float a -> URec Float b Source #

(<$) :: a -> URec Float b -> URec Float a Source #

Functor (URec Int :: Type -> Type) Source #

@since base-4.9.0.0

Instance details

Defined in GHC.Internal.Generics

Methods

fmap :: (a -> b) -> URec Int a -> URec Int b Source #

(<$) :: a -> URec Int b -> URec Int a Source #

Functor (URec Word :: Type -> Type) Source #

@since base-4.9.0.0

Instance details

Defined in GHC.Internal.Generics

Methods

fmap :: (a -> b) -> URec Word a -> URec Word b Source #

(<$) :: a -> URec Word b -> URec Word a Source #

Functor ((,,) a b) Source #

@since base-4.14.0.0

Instance details

Defined in GHC.Internal.Base

Methods

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

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

(Functor f, Functor g) => Functor (f :*: g) Source #

@since base-4.9.0.0

Instance details

Defined in GHC.Internal.Generics

Methods

fmap :: (a -> b) -> (f :*: g) a -> (f :*: g) b Source #

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

(Functor f, Functor g) => Functor (f :+: g) Source #

@since base-4.9.0.0

Instance details

Defined in GHC.Internal.Generics

Methods

fmap :: (a -> b) -> (f :+: g) a -> (f :+: g) b Source #

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

Functor (K1 i c :: Type -> Type) Source #

@since base-4.9.0.0

Instance details

Defined in GHC.Internal.Generics

Methods

fmap :: (a -> b) -> K1 i c a -> K1 i c b Source #

(<$) :: a -> K1 i c b -> K1 i c a Source #

Functor ((,,,) a b c) Source #

@since base-4.14.0.0

Instance details

Defined in GHC.Internal.Base

Methods

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

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

Functor ((->) r) Source #

@since base-2.01

Instance details

Defined in GHC.Internal.Base

Methods

fmap :: (a -> b) -> (r -> a) -> r -> b Source #

(<$) :: a -> (r -> b) -> r -> a Source #

(Functor f, Functor g) => Functor (f :.: g) Source #

@since base-4.9.0.0

Instance details

Defined in GHC.Internal.Generics

Methods

fmap :: (a -> b) -> (f :.: g) a -> (f :.: g) b Source #

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

Functor f => Functor (M1 i c f) Source #

@since base-4.9.0.0

Instance details

Defined in GHC.Internal.Generics

Methods

fmap :: (a -> b) -> M1 i c f a -> M1 i c f b Source #

(<$) :: a -> M1 i c f b -> M1 i c f a Source #

Functor ((,,,,) a b c d) Source #

@since base-4.18.0.0

Instance details

Defined in GHC.Internal.Base

Methods

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

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

Functor ((,,,,,) a b c d e) Source #

@since base-4.18.0.0

Instance details

Defined in GHC.Internal.Base

Methods

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

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

Functor ((,,,,,,) a b c d e f) Source #

@since base-4.18.0.0

Instance details

Defined in GHC.Internal.Base

Methods

fmap :: (a0 -> b0) -> (a, b, c, d, e, f, a0) -> (a, b, c, d, e, f, b0) Source #

(<$) :: a0 -> (a, b, c, d, e, f, b0) -> (a, b, c, d, e, f, a0) Source #

class (Alternative m, Monad m) => MonadPlus (m :: Type -> Type) where Source #

Monads that also support choice and failure.

Minimal complete definition

Nothing

Methods

mzero :: m a Source #

The identity of mplus. It should also satisfy the equations

mzero >>= f  =  mzero
v >> mzero   =  mzero

The default definition is

mzero = empty

mplus :: m a -> m a -> m a Source #

An associative operation. The default definition is

mplus = (<|>)

Instances

Instances details
MonadPlus STM Source #

Takes the first non-retrying STM action.

@since base-4.3.0.0

Instance details

Defined in GHC.Internal.Conc.Sync

Methods

mzero :: STM a Source #

mplus :: STM a -> STM a -> STM a Source #

MonadPlus ReadP Source #

@since base-2.01

Instance details

Defined in GHC.Internal.Text.ParserCombinators.ReadP

Methods

mzero :: ReadP a Source #

mplus :: ReadP a -> ReadP a -> ReadP a Source #

MonadPlus ReadPrec Source #

@since base-2.01

Instance details

Defined in GHC.Internal.Text.ParserCombinators.ReadPrec

MonadPlus IO Source #

Takes the first non-throwing IO action's result. mzero throws an exception.

@since base-4.9.0.0

Instance details

Defined in GHC.Internal.Base

Methods

mzero :: IO a Source #

mplus :: IO a -> IO a -> IO a Source #

MonadPlus Maybe Source #

Picks the leftmost Just value, or, alternatively, Nothing.

@since base-2.01

Instance details

Defined in GHC.Internal.Base

Methods

mzero :: Maybe a Source #

mplus :: Maybe a -> Maybe a -> Maybe a Source #

MonadPlus [] Source #

Combines lists by concatenation, starting from the empty list.

@since base-2.01

Instance details

Defined in GHC.Internal.Base

Methods

mzero :: [a] Source #

mplus :: [a] -> [a] -> [a] Source #

(ArrowApply a, ArrowPlus a) => MonadPlus (ArrowMonad a) Source #

@since base-4.6.0.0

Instance details

Defined in GHC.Internal.Control.Arrow

Methods

mzero :: ArrowMonad a a0 Source #

mplus :: ArrowMonad a a0 -> ArrowMonad a a0 -> ArrowMonad a a0 Source #

MonadPlus (Proxy :: Type -> Type) Source #

@since base-4.9.0.0

Instance details

Defined in GHC.Internal.Data.Proxy

Methods

mzero :: Proxy a Source #

mplus :: Proxy a -> Proxy a -> Proxy a Source #

MonadPlus (U1 :: Type -> Type) Source #

@since base-4.9.0.0

Instance details

Defined in GHC.Internal.Generics

Methods

mzero :: U1 a Source #

mplus :: U1 a -> U1 a -> U1 a Source #

MonadPlus m => MonadPlus (Kleisli m a) Source #

@since base-4.14.0.0

Instance details

Defined in GHC.Internal.Control.Arrow

Methods

mzero :: Kleisli m a a0 Source #

mplus :: Kleisli m a a0 -> Kleisli m a a0 -> Kleisli m a a0 Source #

MonadPlus f => MonadPlus (Ap f) Source #

@since base-4.12.0.0

Instance details

Defined in GHC.Internal.Data.Monoid

Methods

mzero :: Ap f a Source #

mplus :: Ap f a -> Ap f a -> Ap f a Source #

MonadPlus f => MonadPlus (Alt f) Source #

@since base-4.8.0.0

Instance details

Defined in GHC.Internal.Data.Semigroup.Internal

Methods

mzero :: Alt f a Source #

mplus :: Alt f a -> Alt f a -> Alt f a Source #

MonadPlus f => MonadPlus (Rec1 f) Source #

@since base-4.9.0.0

Instance details

Defined in GHC.Internal.Generics

Methods

mzero :: Rec1 f a Source #

mplus :: Rec1 f a -> Rec1 f a -> Rec1 f a Source #

(MonadPlus f, MonadPlus g) => MonadPlus (f :*: g) Source #

@since base-4.9.0.0

Instance details

Defined in GHC.Internal.Generics

Methods

mzero :: (f :*: g) a Source #

mplus :: (f :*: g) a -> (f :*: g) a -> (f :*: g) a Source #

MonadPlus f => MonadPlus (M1 i c f) Source #

@since base-4.9.0.0

Instance details

Defined in GHC.Internal.Generics

Methods

mzero :: M1 i c f a Source #

mplus :: M1 i c f a -> M1 i c f a -> M1 i c f a Source #

mapM :: Monad m => (a -> m b) -> [a] -> m [b] Source #

mapM f is equivalent to sequence . map f.

sequence :: Monad m => [m a] -> m [a] Source #

Evaluate each action in the sequence from left to right, and collect the results.

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

Same as >>=, but with the arguments interchanged.

as >>= f == f =<< as

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

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

'join bss' can be understood as the do expression

do bs <- bss
   bs

Examples

Expand
>>> join [[1, 2, 3], [4, 5, 6], [7, 8, 9]]
[1,2,3,4,5,6,7,8,9]
>>> join (Just (Just 3))
Just 3

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

atomically :: STM a -> IO a

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

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

we can compose them as

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

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

when :: Applicative f => Bool -> f () -> f () Source #

Conditional execution of Applicative expressions. For example,

Examples

Expand
when debug (putStrLn "Debugging")

will output the string Debugging if the Boolean value debug is True, and otherwise do nothing.

>>> putStr "pi:" >> when False (print 3.14159)
pi:

liftM :: Monad m => (a1 -> r) -> m a1 -> m r Source #

Promote a function to a monad. This is equivalent to fmap but specialised to Monads.

liftM2 :: Monad m => (a1 -> a2 -> r) -> m a1 -> m a2 -> m r Source #

Promote a function to a monad, scanning the monadic arguments from left to right.

Examples

Expand
>>> liftM2 (+) [0,1] [0,2]
[0,2,1,3]
>>> liftM2 (+) (Just 1) Nothing
Nothing
>>> liftM2 (+) (+ 3) (* 2) 5
18

liftM3 :: Monad m => (a1 -> a2 -> a3 -> r) -> m a1 -> m a2 -> m a3 -> m r Source #

Promote a function to a monad, scanning the monadic arguments from left to right (cf. liftM2).

liftM4 :: Monad m => (a1 -> a2 -> a3 -> a4 -> r) -> m a1 -> m a2 -> m a3 -> m a4 -> m r Source #

Promote a function to a monad, scanning the monadic arguments from left to right (cf. liftM2).

liftM5 :: Monad m => (a1 -> a2 -> a3 -> a4 -> a5 -> r) -> m a1 -> m a2 -> m a3 -> m a4 -> m a5 -> m r Source #

Promote a function to a monad, scanning the monadic arguments from left to right (cf. liftM2).

ap :: Monad m => m (a -> b) -> m a -> m b Source #

In many situations, the liftM operations can be replaced by uses of ap, which promotes function application.

return f `ap` x1 `ap` ... `ap` xn

is equivalent to

liftM<n> f x1 x2 ... xn

Examples

Expand
>>> pure (\x y z -> x + y * z) `ap` Just 1 `ap` Just 5 `ap` Just 10
Just 51

class Semigroup a => Monoid a where Source #

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) <> z (Semigroup law)
Concatenation
mconcat = foldr (<>) mempty

You can alternatively define mconcat instead of mempty, in which case the laws are:

Unit
mconcat (pure x) = x
Multiplication
mconcat (join xss) = mconcat (fmap mconcat xss)
Subclass
mconcat (toList xs) = sconcat xs

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

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

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

Minimal complete definition

mempty | mconcat

Methods

mempty :: a Source #

Identity of mappend

Examples

Expand
>>> "Hello world" <> mempty
"Hello world"
>>> mempty <> [1, 2, 3]
[1,2,3]

mappend :: a -> a -> a Source #

An associative operation

NOTE: This method is redundant and has the default implementation mappend = (<>) since base-4.11.0.0. Should it be implemented manually, since mappend is a synonym for (<>), it is expected that the two functions are defined the same way. In a future GHC release mappend will be removed from Monoid.

mconcat :: [a] -> a Source #

Fold a list using the monoid.

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

>>> mconcat ["Hello", " ", "Haskell", "!"]
"Hello Haskell!"

Instances

Instances details
Monoid All Source #

@since base-2.01

Instance details

Defined in GHC.Internal.Data.Semigroup.Internal

Monoid Any Source #

@since base-2.01

Instance details

Defined in GHC.Internal.Data.Semigroup.Internal

Monoid Event Source #

@since base-4.4.0.0

Instance details

Defined in GHC.Internal.Event.Internal.Types

Monoid Lifetime Source #

mappend takes the longer of two lifetimes.

@since base-4.8.0.0

Instance details

Defined in GHC.Internal.Event.Internal.Types

Monoid ExceptionContext Source # 
Instance details

Defined in GHC.Internal.Exception.Context

Monoid Ordering Source #

@since base-2.01

Instance details

Defined in GHC.Internal.Base

Monoid () Source #

@since base-2.01

Instance details

Defined in GHC.Internal.Base

Methods

mempty :: () Source #

mappend :: () -> () -> () Source #

mconcat :: [()] -> () Source #

Monoid a => Monoid (STM a) Source #

@since base-4.17.0.0

Instance details

Defined in GHC.Internal.Conc.Sync

Methods

mempty :: STM a Source #

mappend :: STM a -> STM a -> STM a Source #

mconcat :: [STM a] -> STM a Source #

FiniteBits a => Monoid (And a) Source #

This constraint is arguably too strong. However, as some types (such as Natural) have undefined complement, this is the only safe choice.

@since base-4.16

Instance details

Defined in GHC.Internal.Data.Bits

Methods

mempty :: And a Source #

mappend :: And a -> And a -> And a Source #

mconcat :: [And a] -> And a Source #

FiniteBits a => Monoid (Iff a) Source #

This constraint is arguably too strong. However, as some types (such as Natural) have undefined complement, this is the only safe choice.

@since base-4.16

Instance details

Defined in GHC.Internal.Data.Bits

Methods

mempty :: Iff a Source #

mappend :: Iff a -> Iff a -> Iff a Source #

mconcat :: [Iff a] -> Iff a Source #

Bits a => Monoid (Ior a) Source #

@since base-4.16

Instance details

Defined in GHC.Internal.Data.Bits

Methods

mempty :: Ior a Source #

mappend :: Ior a -> Ior a -> Ior a Source #

mconcat :: [Ior a] -> Ior a Source #

Bits a => Monoid (Xor a) Source #

@since base-4.16

Instance details

Defined in GHC.Internal.Data.Bits

Methods

mempty :: Xor a Source #

mappend :: Xor a -> Xor a -> Xor a Source #

mconcat :: [Xor a] -> Xor a Source #

Monoid a => Monoid (Identity a) Source #

@since base-4.9.0.0

Instance details

Defined in GHC.Internal.Data.Functor.Identity

Ord a => Monoid (Max a) Source #

@since base-4.8.0.0

Instance details

Defined in GHC.Internal.Data.Functor.Utils

Methods

mempty :: Max a Source #

mappend :: Max a -> Max a -> Max a Source #

mconcat :: [Max a] -> Max a Source #

Ord a => Monoid (Min a) Source #

@since base-4.8.0.0

Instance details

Defined in GHC.Internal.Data.Functor.Utils

Methods

mempty :: Min a Source #

mappend :: Min a -> Min a -> Min a Source #

mconcat :: [Min a] -> Min a Source #

Monoid (First a) Source #

@since base-2.01

Instance details

Defined in GHC.Internal.Data.Monoid

Methods

mempty :: First a Source #

mappend :: First a -> First a -> First a Source #

mconcat :: [First a] -> First a Source #

Monoid (Last a) Source #

@since base-2.01

Instance details

Defined in GHC.Internal.Data.Monoid

Methods

mempty :: Last a Source #

mappend :: Last a -> Last a -> Last a Source #

mconcat :: [Last a] -> Last a Source #

Monoid a => Monoid (Down a) Source #

@since base-4.11.0.0

Instance details

Defined in GHC.Internal.Data.Ord

Methods

mempty :: Down a Source #

mappend :: Down a -> Down a -> Down a Source #

mconcat :: [Down a] -> Down a Source #

Monoid a => Monoid (Dual a) Source #

@since base-2.01

Instance details

Defined in GHC.Internal.Data.Semigroup.Internal

Methods

mempty :: Dual a Source #

mappend :: Dual a -> Dual a -> Dual a Source #

mconcat :: [Dual a] -> Dual a Source #

Monoid (Endo a) Source #

@since base-2.01

Instance details

Defined in GHC.Internal.Data.Semigroup.Internal

Methods

mempty :: Endo a Source #

mappend :: Endo a -> Endo a -> Endo a Source #

mconcat :: [Endo a] -> Endo a Source #

Num a => Monoid (Product a) Source #

@since base-2.01

Instance details

Defined in GHC.Internal.Data.Semigroup.Internal

Num a => Monoid (Sum a) Source #

@since base-2.01

Instance details

Defined in GHC.Internal.Data.Semigroup.Internal

Methods

mempty :: Sum a Source #

mappend :: Sum a -> Sum a -> Sum a Source #

mconcat :: [Sum a] -> Sum a Source #

(Generic a, Monoid (Rep a ())) => Monoid (Generically a) Source #

@since base-4.17.0.0

Instance details

Defined in GHC.Internal.Generics

Monoid p => Monoid (Par1 p) Source #

@since base-4.12.0.0

Instance details

Defined in GHC.Internal.Generics

Methods

mempty :: Par1 p Source #

mappend :: Par1 p -> Par1 p -> Par1 p Source #

mconcat :: [Par1 p] -> Par1 p Source #

Monoid a => Monoid (IO a) Source #

@since base-4.9.0.0

Instance details

Defined in GHC.Internal.Base

Methods

mempty :: IO a Source #

mappend :: IO a -> IO a -> IO a Source #

mconcat :: [IO a] -> IO a Source #

Semigroup a => Monoid (Maybe a) Source #

Lift a semigroup into Maybe forming a Monoid according to http://en.wikipedia.org/wiki/Monoid: "Any semigroup S may be turned into a monoid simply by adjoining an element e not in S and defining e*e = e and e*s = s = s*e for all s ∈ S."

Since 4.11.0: constraint on inner a value generalised from Monoid to Semigroup.

@since base-2.01

Instance details

Defined in GHC.Internal.Base

Methods

mempty :: Maybe a Source #

mappend :: Maybe a -> Maybe a -> Maybe a Source #

mconcat :: [Maybe a] -> Maybe a Source #

Monoid a => Monoid (Solo a) Source #

@since base-4.15

Instance details

Defined in GHC.Internal.Base

Methods

mempty :: Solo a Source #

mappend :: Solo a -> Solo a -> Solo a Source #

mconcat :: [Solo a] -> Solo a Source #

Monoid [a] Source #

@since base-2.01

Instance details

Defined in GHC.Internal.Base

Methods

mempty :: [a] Source #

mappend :: [a] -> [a] -> [a] Source #

mconcat :: [[a]] -> [a] Source #

Monoid (Proxy s) Source #

@since base-4.7.0.0

Instance details

Defined in GHC.Internal.Data.Proxy

Methods

mempty :: Proxy s Source #

mappend :: Proxy s -> Proxy s -> Proxy s Source #

mconcat :: [Proxy s] -> Proxy s Source #

Monoid (U1 p) Source #

@since base-4.12.0.0

Instance details

Defined in GHC.Internal.Generics

Methods

mempty :: U1 p Source #

mappend :: U1 p -> U1 p -> U1 p Source #

mconcat :: [U1 p] -> U1 p Source #

Monoid a => Monoid (ST s a) Source #

@since base-4.11.0.0

Instance details

Defined in GHC.Internal.ST

Methods

mempty :: ST s a Source #

mappend :: ST s a -> ST s a -> ST s a Source #

mconcat :: [ST s a] -> ST s a Source #

(Monoid a, Monoid b) => Monoid (a, b) Source #

@since base-2.01

Instance details

Defined in GHC.Internal.Base

Methods

mempty :: (a, b) Source #

mappend :: (a, b) -> (a, b) -> (a, b) Source #

mconcat :: [(a, b)] -> (a, b) Source #

Monoid b => Monoid (a -> b) Source #

@since base-2.01

Instance details

Defined in GHC.Internal.Base

Methods

mempty :: a -> b Source #

mappend :: (a -> b) -> (a -> b) -> a -> b Source #

mconcat :: [a -> b] -> a -> b Source #

Monoid a => Monoid (Const a b) Source #

@since base-4.9.0.0

Instance details

Defined in GHC.Internal.Data.Functor.Const

Methods

mempty :: Const a b Source #

mappend :: Const a b -> Const a b -> Const a b Source #

mconcat :: [Const a b] -> Const a b Source #

(Applicative f, Monoid a) => Monoid (Ap f a) Source #

@since base-4.12.0.0

Instance details

Defined in GHC.Internal.Data.Monoid

Methods

mempty :: Ap f a Source #

mappend :: Ap f a -> Ap f a -> Ap f a Source #

mconcat :: [Ap f a] -> Ap f a Source #

Alternative f => Monoid (Alt f a) Source #

@since base-4.8.0.0

Instance details

Defined in GHC.Internal.Data.Semigroup.Internal

Methods

mempty :: Alt f a Source #

mappend :: Alt f a -> Alt f a -> Alt f a Source #

mconcat :: [Alt f a] -> Alt f a Source #

Monoid (f p) => Monoid (Rec1 f p) Source #

@since base-4.12.0.0

Instance details

Defined in GHC.Internal.Generics

Methods

mempty :: Rec1 f p Source #

mappend :: Rec1 f p -> Rec1 f p -> Rec1 f p Source #

mconcat :: [Rec1 f p] -> Rec1 f p Source #

(Monoid a, Monoid b, Monoid c) => Monoid (a, b, c) Source #

@since base-2.01

Instance details

Defined in GHC.Internal.Base

Methods

mempty :: (a, b, c) Source #

mappend :: (a, b, c) -> (a, b, c) -> (a, b, c) Source #

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

(Monoid (f p), Monoid (g p)) => Monoid ((f :*: g) p) Source #

@since base-4.12.0.0

Instance details

Defined in GHC.Internal.Generics

Methods

mempty :: (f :*: g) p Source #

mappend :: (f :*: g) p -> (f :*: g) p -> (f :*: g) p Source #

mconcat :: [(f :*: g) p] -> (f :*: g) p Source #

Monoid c => Monoid (K1 i c p) Source #

@since base-4.12.0.0

Instance details

Defined in GHC.Internal.Generics

Methods

mempty :: K1 i c p Source #

mappend :: K1 i c p -> K1 i c p -> K1 i c p Source #

mconcat :: [K1 i c p] -> K1 i c p Source #

(Monoid a, Monoid b, Monoid c, Monoid d) => Monoid (a, b, c, d) Source #

@since base-2.01

Instance details

Defined in GHC.Internal.Base

Methods

mempty :: (a, b, c, d) Source #

mappend :: (a, b, c, d) -> (a, b, c, d) -> (a, b, c, d) Source #

mconcat :: [(a, b, c, d)] -> (a, b, c, d) Source #

Monoid (f (g p)) => Monoid ((f :.: g) p) Source #

@since base-4.12.0.0

Instance details

Defined in GHC.Internal.Generics

Methods

mempty :: (f :.: g) p Source #

mappend :: (f :.: g) p -> (f :.: g) p -> (f :.: g) p Source #

mconcat :: [(f :.: g) p] -> (f :.: g) p Source #

Monoid (f p) => Monoid (M1 i c f p) Source #

@since base-4.12.0.0

Instance details

Defined in GHC.Internal.Generics

Methods

mempty :: M1 i c f p Source #

mappend :: M1 i c f p -> M1 i c f p -> M1 i c f p Source #

mconcat :: [M1 i c f p] -> M1 i c f p Source #

(Monoid a, Monoid b, Monoid c, Monoid d, Monoid e) => Monoid (a, b, c, d, e) Source #

@since base-2.01

Instance details

Defined in GHC.Internal.Base

Methods

mempty :: (a, b, c, d, e) Source #

mappend :: (a, b, c, d, e) -> (a, b, c, d, e) -> (a, b, c, d, e) Source #

mconcat :: [(a, b, c, d, e)] -> (a, b, c, d, e) Source #

data NonEmpty a Source #

Non-empty (and non-strict) list type.

@since base-4.9.0.0

Constructors

a :| [a] infixr 5 

Instances

Instances details
Applicative NonEmpty Source #

@since base-4.9.0.0

Instance details

Defined in GHC.Internal.Base

Methods

pure :: a -> NonEmpty a Source #

(<*>) :: NonEmpty (a -> b) -> NonEmpty a -> NonEmpty b Source #

liftA2 :: (a -> b -> c) -> NonEmpty a -> NonEmpty b -> NonEmpty c Source #

(*>) :: NonEmpty a -> NonEmpty b -> NonEmpty b Source #

(<*) :: NonEmpty a -> NonEmpty b -> NonEmpty a Source #

Functor NonEmpty Source #

@since base-4.9.0.0

Instance details

Defined in GHC.Internal.Base

Methods

fmap :: (a -> b) -> NonEmpty a -> NonEmpty b Source #

(<$) :: a -> NonEmpty b -> NonEmpty a Source #

Monad NonEmpty Source #

@since base-4.9.0.0

Instance details

Defined in GHC.Internal.Base

Methods

(>>=) :: NonEmpty a -> (a -> NonEmpty b) -> NonEmpty b Source #

(>>) :: NonEmpty a -> NonEmpty b -> NonEmpty b Source #

return :: a -> NonEmpty a Source #

MonadFix NonEmpty Source #

@since base-4.9.0.0

Instance details

Defined in GHC.Internal.Control.Monad.Fix

Methods

mfix :: (a -> NonEmpty a) -> NonEmpty a Source #

Foldable NonEmpty Source #

@since base-4.9.0.0

Instance details

Defined in GHC.Internal.Data.Foldable

Methods

fold :: Monoid m => NonEmpty m -> m Source #

foldMap :: Monoid m => (a -> m) -> NonEmpty a -> m Source #

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

foldr :: (a -> b -> b) -> b -> NonEmpty a -> b Source #

foldr' :: (a -> b -> b) -> b -> NonEmpty a -> b Source #

foldl :: (b -> a -> b) -> b -> NonEmpty a -> b Source #

foldl' :: (b -> a -> b) -> b -> NonEmpty a -> b Source #

foldr1 :: (a -> a -> a) -> NonEmpty a -> a Source #

foldl1 :: (a -> a -> a) -> NonEmpty a -> a Source #

toList :: NonEmpty a -> [a] Source #

null :: NonEmpty a -> Bool Source #

length :: NonEmpty a -> Int Source #

elem :: Eq a => a -> NonEmpty a -> Bool Source #

maximum :: Ord a => NonEmpty a -> a Source #

minimum :: Ord a => NonEmpty a -> a Source #

sum :: Num a => NonEmpty a -> a Source #

product :: Num a => NonEmpty a -> a Source #

Traversable NonEmpty Source #

@since base-4.9.0.0

Instance details

Defined in GHC.Internal.Data.Traversable

Methods

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

sequenceA :: Applicative f => NonEmpty (f a) -> f (NonEmpty a) Source #

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

sequence :: Monad m => NonEmpty (m a) -> m (NonEmpty a) Source #

Generic1 NonEmpty Source # 
Instance details

Defined in GHC.Internal.Generics

Associated Types

type Rep1 NonEmpty

@since base-4.6.0.0

Instance details

Defined in GHC.Internal.Generics

type Rep1 NonEmpty = D1 ('MetaData "NonEmpty" "GHC.Internal.Base" "ghc-internal" 'False) (C1 ('MetaCons ":|" ('InfixI 'RightAssociative 5) 'False) (S1 ('MetaSel ('Nothing :: Maybe Symbol) 'NoSourceUnpackedness 'NoSourceStrictness 'DecidedLazy) Par1 :*: S1 ('MetaSel ('Nothing :: Maybe Symbol) '