copilot-language-3.11: A Haskell-embedded DSL for monitoring hard real-time distributed systems.
Safe HaskellSafe
LanguageHaskell2010

Copilot.Language.Prelude

Description

Reexports Prelude from package "base" hiding identifiers redefined by Copilot.

Synopsis

Documentation

seq :: forall {r :: RuntimeRep} a (b :: TYPE r). a -> b -> b infixr 0 #

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

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

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

\(\mathcal{O}(n)\). filter, applied to a predicate and a list, returns the list of those elements that satisfy the predicate; i.e.,

filter p xs = [ x | x <- xs, p x]
>>> filter odd [1, 2, 3]
[1,3]

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

\(\mathcal{O}(\min(m,n))\). zip takes two lists and returns a list of corresponding pairs.

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

If one input list is shorter than the other, excess elements of the longer list are discarded, even if one of the lists is infinite:

>>> zip [1] ['a', 'b']
[(1,'a')]
>>> zip [1, 2] ['a']
[(1,'a')]
>>> zip [] [1..]
[]
>>> zip [1..] []
[]

zip is right-lazy:

>>> zip [] undefined
[]
>>> zip undefined []
*** Exception: Prelude.undefined
...

zip is capable of list fusion, but it is restricted to its first list argument and its resulting list.

print :: Show a => a -> IO () #

The print function outputs a value of any printable type to the standard output device. Printable types are those that are instances of class Show; print converts values to strings for output using the show operation and adds a newline.

For example, a program to print the first 20 integers and their powers of 2 could be written as:

main = print ([(n, 2^n) | n <- [0..19]])

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

Extract the first component of a pair.

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

Extract the second component of a pair.

otherwise :: Bool #

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

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

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

\(\mathcal{O}(n)\). map f xs is the list obtained by applying f to each element of xs, i.e.,

map f [x1, x2, ..., xn] == [f x1, f x2, ..., f xn]
map f [x1, x2, ...] == [f x1, f x2, ...]
>>> map (+1) [1, 2, 3]
[2,3,4]

($) :: 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 $ x). However, $ has low, right-associative binding precedence, so it sometimes allows parentheses to be omitted; for example:

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

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

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

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

general coercion from integral types

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

general coercion to fractional types

class Bounded a where #

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

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

Methods

minBound :: a #

maxBound :: a #

Instances

Instances details
Bounded All

Since: base-2.1

Instance details

Defined in Data.Semigroup.Internal

Methods

minBound :: All #

maxBound :: All #

Bounded Any

Since: base-2.1

Instance details

Defined in Data.Semigroup.Internal

Methods

minBound :: Any #

maxBound :: Any #

Bounded Associativity

Since: base-4.9.0.0

Instance details

Defined in GHC.Generics

Bounded DecidedStrictness

Since: base-4.9.0.0

Instance details

Defined in GHC.Generics

Bounded SourceStrictness

Since: base-4.9.0.0

Instance details

Defined in GHC.Generics

Bounded SourceUnpackedness

Since: base-4.9.0.0

Instance details

Defined in GHC.Generics

Bounded Int16

Since: base-2.1

Instance details

Defined in GHC.Int

Bounded Int32

Since: base-2.1

Instance details

Defined in GHC.Int

Bounded Int64

Since: base-2.1

Instance details

Defined in GHC.Int

Bounded Int8

Since: base-2.1

Instance details

Defined in GHC.Int

Bounded Word16

Since: base-2.1

Instance details

Defined in GHC.Word

Bounded Word32

Since: base-2.1

Instance details

Defined in GHC.Word

Bounded Word64

Since: base-2.1

Instance details

Defined in GHC.Word

Bounded Word8

Since: base-2.1

Instance details

Defined in GHC.Word

Bounded Ordering

Since: base-2.1

Instance details

Defined in GHC.Enum

Bounded ()

Since: base-2.1

Instance details

Defined in GHC.Enum

Methods

minBound :: () #

maxBound :: () #

Bounded Bool

Since: base-2.1

Instance details

Defined in GHC.Enum

Bounded Char

Since: base-2.1

Instance details

Defined in GHC.Enum

Bounded Int

Since: base-2.1

Instance details

Defined in GHC.Enum

Methods

minBound :: Int #

maxBound :: Int #

Bounded Levity

Since: base-4.16.0.0

Instance details

Defined in GHC.Enum

Bounded VecCount

Since: base-4.10.0.0

Instance details

Defined in GHC.Enum

Bounded VecElem

Since: base-4.10.0.0

Instance details

Defined in GHC.Enum

Bounded Word

Since: base-2.1

Instance details

Defined in GHC.Enum

Bounded a => Bounded (And a)

Since: base-4.16

Instance details

Defined in Data.Bits

Methods

minBound :: And a #

maxBound :: And a #

Bounded a => Bounded (Iff a)

Since: base-4.16

Instance details

Defined in Data.Bits

Methods

minBound :: Iff a #

maxBound :: Iff a #

Bounded a => Bounded (Ior a)

Since: base-4.16

Instance details

Defined in Data.Bits

Methods

minBound :: Ior a #

maxBound :: Ior a #

Bounded a => Bounded (Xor a)

Since: base-4.16

Instance details

Defined in Data.Bits

Methods

minBound :: Xor a #

maxBound :: Xor a #

Bounded a => Bounded (Identity a)

Since: base-4.9.0.0

Instance details

Defined in Data.Functor.Identity

Bounded a => Bounded (Down a)

Swaps minBound and maxBound of the underlying type.

Since: base-4.14.0.0

Instance details

Defined in Data.Ord

Methods

minBound :: Down a #

maxBound :: Down a #

Bounded a => Bounded (Dual a)

Since: base-2.1

Instance details

Defined in Data.Semigroup.Internal

Methods

minBound :: Dual a #

maxBound :: Dual a #

Bounded a => Bounded (Product a)

Since: base-2.1

Instance details

Defined in Data.Semigroup.Internal

Bounded a => Bounded (Sum a)

Since: base-2.1

Instance details

Defined in Data.Semigroup.Internal

Methods

minBound :: Sum a #

maxBound :: Sum a #

Bounded a => Bounded (a) 
Instance details

Defined in GHC.Enum

Methods

minBound :: (a) #

maxBound :: (a) #

Bounded (Proxy t)

Since: base-4.7.0.0

Instance details

Defined in Data.Proxy

Methods

minBound :: Proxy t #

maxBound :: Proxy t #

(Bounded a, Bounded b) => Bounded (a, b)

Since: base-2.1

Instance details

Defined in GHC.Enum

Methods

minBound :: (a, b) #

maxBound :: (a, b) #

(Applicative f, Bounded a) => Bounded (Ap f a)

Since: base-4.12.0.0

Instance details

Defined in Data.Monoid

Methods

minBound :: Ap f a #

maxBound :: Ap f a #

a ~ b => Bounded (a :~: b)

Since: base-4.7.0.0

Instance details

Defined in Data.Type.Equality

Methods

minBound :: a :~: b #

maxBound :: a :~: b #

(Bounded a, Bounded b, Bounded c) => Bounded (a, b, c)

Since: base-2.1

Instance details

Defined in GHC.Enum

Methods

minBound :: (a, b, c) #

maxBound :: (a, b, c) #

a ~~ b => Bounded (a :~~: b)

Since: base-4.10.0.0

Instance details

Defined in Data.Type.Equality

Methods

minBound :: a :~~: b #

maxBound :: a :~~: b #

(Bounded a, Bounded b, Bounded c, Bounded d) => Bounded (a, b, c, d)

Since: base-2.1

Instance details

Defined in GHC.Enum

Methods

minBound :: (a, b, c, d) #

maxBound :: (a, b, c, d) #

(Bounded a, Bounded b, Bounded c, Bounded d, Bounded e) => Bounded (a, b, c, d, e)

Since: base-2.1

Instance details

Defined in GHC.Enum

Methods

minBound :: (a, b, c, d, e) #

maxBound :: (a, b, c, d, e) #

(Bounded a, Bounded b, Bounded c, Bounded d, Bounded e, Bounded f) => Bounded (a, b, c, d, e, f)

Since: base-2.1

Instance details

Defined in GHC.Enum

Methods

minBound :: (a, b, c, d, e, f) #

maxBound :: (a, b, c, d, e, f) #

(Bounded a, Bounded b, Bounded c, Bounded d, Bounded e, Bounded f, Bounded g) => Bounded (a, b, c, d, e, f, g)

Since: base-2.1

Instance details

Defined in GHC.Enum

Methods

minBound :: (a, b, c, d, e, f, g) #

maxBound :: (a, b, c, d, e, f, g) #

(Bounded a, Bounded b, Bounded c, Bounded d, Bounded e, Bounded f, Bounded g, Bounded h) => Bounded (a, b, c, d, e, f, g, h)

Since: base-2.1

Instance details

Defined in GHC.Enum

Methods

minBound :: (a, b, c, d, e, f, g, h) #

maxBound :: (a, b, c, d, e, f, g, h) #

(Bounded a, Bounded b, Bounded c, Bounded d, Bounded e, Bounded f, Bounded g, Bounded h, Bounded i) => Bounded (a, b, c, d, e, f, g, h, i)

Since: base-2.1

Instance details

Defined in GHC.Enum

Methods

minBound :: (a, b, c, d, e, f, g, h, i) #

maxBound :: (a, b, c, d, e, f, g, h, i) #

(Bounded a, Bounded b, Bounded c, Bounded d, Bounded e, Bounded f, Bounded g, Bounded h, Bounded i, Bounded j) => Bounded (a, b, c, d, e, f, g, h, i, j)

Since: base-2.1

Instance details

Defined in GHC.Enum

Methods

minBound :: (a, b, c, d, e, f, g, h, i, j) #

maxBound :: (a, b, c, d, e, f, g, h, i, j) #

(Bounded a, Bounded b, Bounded c, Bounded d, Bounded e, Bounded f, Bounded g, Bounded h, Bounded i, Bounded j, Bounded k) => Bounded (a, b, c, d, e, f, g, h, i, j, k)

Since: base-2.1

Instance details

Defined in GHC.Enum

Methods

minBound :: (a, b, c, d, e, f, g, h, i, j, k) #

maxBound :: (a, b, c, d, e, f, g, h, i, j, k) #

(Bounded a, Bounded b, Bounded c, Bounded d, Bounded e, Bounded f, Bounded g, Bounded h, Bounded i, Bounded j, Bounded k, Bounded l) => Bounded (a, b, c, d, e, f, g, h, i, j, k, l)

Since: base-2.1

Instance details

Defined in GHC.Enum

Methods

minBound :: (a, b, c, d, e, f, g, h, i, j, k, l) #

maxBound :: (a, b, c, d, e, f, g, h, i, j, k, l) #

(Bounded a, Bounded b, Bounded c, Bounded d, Bounded e, Bounded f, Bounded g, Bounded h, Bounded i, Bounded j, Bounded k, Bounded l, Bounded m) => Bounded (a, b, c, d, e, f, g, h, i, j, k, l, m)

Since: base-2.1

Instance details

Defined in GHC.Enum

Methods

minBound :: (a, b, c, d, e, f, g, h, i, j, k, l, m) #

maxBound :: (a, b, c, d, e, f, g, h, i, j, k, l, m) #

(Bounded a, Bounded b, Bounded c, Bounded d, Bounded e, Bounded f, Bounded g, Bounded h, Bounded i, Bounded j, Bounded k, Bounded l, Bounded m, Bounded n) => Bounded (a, b, c, d, e, f, g, h, i, j, k, l, m, n)

Since: base-2.1

Instance details

Defined in GHC.Enum

Methods

minBound :: (a, b, c, d, e, f, g, h, i, j, k, l, m, n) #

maxBound :: (a, b, c, d, e, f, g, h, i, j, k, l, m, n) #

(Bounded a, Bounded b, Bounded c, Bounded d, Bounded e, Bounded f, Bounded g, Bounded h, Bounded i, Bounded j, Bounded k, Bounded l, Bounded m, Bounded n, Bounded o) => Bounded (a, b, c, d, e, f, g, h, i, j, k, l, m, n, o)

Since: base-2.1

Instance details

Defined in GHC.Enum

Methods

minBound :: (a, b, c, d, e, f, g, h, i, j, k, l, m, n, o) #

maxBound :: (a, b, c, d, e, f, g, h, i, j, k, l, m, n, o) #

class Enum a where #

Class Enum defines operations on sequentially ordered types.

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

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

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

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

Minimal complete definition

toEnum, fromEnum

Methods

succ :: a -> a #

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

pred :: a -> a #

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

toEnum :: Int -> a #

Convert from an Int.

fromEnum :: a -> Int #

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

enumFrom :: a -> [a] #

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

  • enumFrom 4 :: [Integer] = [4,5,6,7,...]
  • enumFrom 6 :: [Int] = [6,7,8,9,...,maxBound :: Int]

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

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

  • enumFromThen 4 6 :: [Integer] = [4,6,8,10...]
  • enumFromThen 6 2 :: [Int] = [6,2,-2,-6,...,minBound :: Int]

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

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

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

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

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

  • enumFromThenTo 4 2 -6 :: [Integer] = [4,2,0,-2,-4,-6]
  • enumFromThenTo 6 8 2 :: [Int] = []

Instances

Instances details
Enum Associativity

Since: base-4.9.0.0

Instance details

Defined in GHC.Generics

Enum DecidedStrictness

Since: base-4.9.0.0

Instance details

Defined in GHC.Generics

Enum SourceStrictness

Since: base-4.9.0.0

Instance details

Defined in GHC.Generics

Enum SourceUnpackedness

Since: base-4.9.0.0

Instance details

Defined in GHC.Generics

Enum Int16

Since: base-2.1

Instance details

Defined in GHC.Int

Enum Int32

Since: base-2.1

Instance details

Defined in GHC.Int

Enum Int64

Since: base-2.1

Instance details

Defined in GHC.Int

Enum Int8

Since: base-2.1

Instance details

Defined in GHC.Int

Methods

succ :: Int8 -> Int8 #

pred :: Int8 -> Int8 #

toEnum :: Int -> Int8 #

fromEnum :: Int8 -> Int #

enumFrom :: Int8 -> [Int8] #

enumFromThen :: Int8 -> Int8 -> [Int8] #

enumFromTo :: Int8 -> Int8 -> [Int8] #

enumFromThenTo :: Int8 -> Int8 -> Int8 -> [Int8] #

Enum Word16

Since: base-2.1

Instance details

Defined in GHC.Word

Enum Word32

Since: base-2.1

Instance details

Defined in GHC.Word

Enum Word64

Since: base-2.1

Instance details

Defined in GHC.Word

Enum Word8

Since: base-2.1

Instance details

Defined in GHC.Word

Enum Ordering

Since: base-2.1

Instance details

Defined in GHC.Enum

Enum Integer

Since: base-2.1

Instance details

Defined in GHC.Enum

Enum Natural

Since: base-4.8.0.0

Instance details

Defined in GHC.Enum

Enum ()

Since: base-2.1

Instance details

Defined in GHC.Enum

Methods

succ :: () -> () #

pred :: () -> () #

toEnum :: Int -> () #

fromEnum :: () -> Int #

enumFrom :: () -> [()] #

enumFromThen :: () -> () -> [()] #

enumFromTo :: () -> () -> [()] #

enumFromThenTo :: () -> () -> () -> [()] #

Enum Bool

Since: base-2.1

Instance details

Defined in GHC.Enum

Methods

succ :: Bool -> Bool #

pred :: Bool -> Bool #

toEnum :: Int -> Bool #

fromEnum :: Bool -> Int #

enumFrom :: Bool -> [Bool] #

enumFromThen :: Bool -> Bool -> [Bool] #

enumFromTo :: Bool -> Bool -> [Bool] #

enumFromThenTo :: Bool -> Bool -> Bool -> [Bool] #

Enum Char

Since: base-2.1

Instance details

Defined in GHC.Enum

Methods

succ :: Char -> Char #

pred :: Char -> Char #

toEnum :: Int -> Char #

fromEnum :: Char -> Int #

enumFrom :: Char -> [Char] #

enumFromThen :: Char -> Char -> [Char] #

enumFromTo :: Char -> Char -> [Char] #

enumFromThenTo :: Char -> Char -> Char -> [Char] #

Enum Int

Since: base-2.1

Instance details

Defined in GHC.Enum

Methods

succ :: Int -> Int #

pred :: Int -> Int #

toEnum :: Int -> Int #

fromEnum :: Int -> Int #

enumFrom :: Int -> [Int] #

enumFromThen :: Int -> Int -> [Int] #

enumFromTo :: Int -> Int -> [Int] #

enumFromThenTo :: Int -> Int -> Int -> [Int] #

Enum Levity

Since: base-4.16.0.0

Instance details

Defined in GHC.Enum

Enum VecCount

Since: base-4.10.0.0

Instance details

Defined in GHC.Enum

Enum VecElem

Since: base-4.10.0.0

Instance details

Defined in GHC.Enum

Enum Word

Since: base-2.1

Instance details

Defined in GHC.Enum

Methods

succ :: Word -> Word #

pred :: Word -> Word #

toEnum :: Int -> Word #

fromEnum :: Word -> Int #

enumFrom :: Word -> [Word] #

enumFromThen :: Word -> Word -> [Word] #

enumFromTo :: Word -> Word -> [Word] #

enumFromThenTo :: Word -> Word -> Word -> [Word] #

Enum a => Enum (And a)

Since: base-4.16

Instance details

Defined in Data.Bits

Methods

succ :: And a -> And a #

pred :: And a -> And a #

toEnum :: Int -> And a #

fromEnum :: And a -> Int #

enumFrom :: And a -> [And a] #

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

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

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

Enum a => Enum (Iff a)

Since: base-4.16

Instance details

Defined in Data.Bits

Methods

succ :: Iff a -> Iff a #

pred :: Iff a -> Iff a #

toEnum :: Int -> Iff a #

fromEnum :: Iff a -> Int #

enumFrom :: Iff a -> [Iff a] #

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

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

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

Enum a => Enum (Ior a)

Since: base-4.16

Instance details

Defined in Data.Bits

Methods

succ :: Ior a -> Ior a #

pred :: Ior a -> Ior a #

toEnum :: Int -> Ior a #

fromEnum :: Ior a -> Int #

enumFrom :: Ior a -> [Ior a] #

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

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

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

Enum a => Enum (Xor a)

Since: base-4.16

Instance details

Defined in Data.Bits

Methods

succ :: Xor a -> Xor a #

pred :: Xor a -> Xor a #

toEnum :: Int -> Xor a #

fromEnum :: Xor a -> Int #

enumFrom :: Xor a -> [Xor a] #

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

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

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

Enum a => Enum (Identity a)

Since: base-4.9.0.0

Instance details

Defined in Data.Functor.Identity

Integral a => Enum (Ratio a)

Since: base-2.0.1

Instance details

Defined in GHC.Real

Methods

succ :: Ratio a -> Ratio a #

pred :: Ratio a -> Ratio a #

toEnum :: Int -> Ratio a #

fromEnum :: Ratio a -> Int #

enumFrom :: Ratio a -> [Ratio a] #

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

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

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

Enum a => Enum (a) 
Instance details

Defined in GHC.Enum

Methods

succ :: (a) -> (a) #

pred :: (a) -> (a) #

toEnum :: Int -> (a) #

fromEnum :: (a) -> Int #

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

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

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

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

Enum (Proxy s)

Since: base-4.7.0.0

Instance details

Defined in Data.Proxy

Methods

succ :: Proxy s -> Proxy s #

pred :: Proxy s -> Proxy s #

toEnum :: Int -> Proxy s #

fromEnum :: Proxy s -> Int #

enumFrom :: Proxy s -> [Proxy s] #

enumFromThen :: Proxy s -> Proxy s -> [Proxy s] #

enumFromTo :: Proxy s -> Proxy s -> [Proxy s] #

enumFromThenTo :: Proxy s -> Proxy s -> Proxy s -> [Proxy s] #

Enum (f a) => Enum (Ap f a)

Since: base-4.12.0.0

Instance details

Defined in Data.Monoid

Methods

succ :: Ap f a -> Ap f a #

pred :: Ap f a -> Ap f a #

toEnum :: Int -> Ap f a #

fromEnum :: Ap f a -> Int #

enumFrom :: Ap f a -> [Ap f a] #

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

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

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

Enum (f a) => Enum (Alt f a)

Since: base-4.8.0.0

Instance details

Defined in Data.Semigroup.Internal

Methods

succ :: Alt f a -> Alt f a #

pred :: Alt f a -> Alt f a #

toEnum :: Int -> Alt f a #

fromEnum :: Alt f a -> Int #

enumFrom :: Alt f a -> [Alt f a] #

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

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

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

a ~ b => Enum (a :~: b)

Since: base-4.7.0.0

Instance details

Defined in Data.Type.Equality

Methods

succ :: (a :~: b) -> a :~: b #

pred :: (a :~: b) -> a :~: b #

toEnum :: Int -> a :~: b #

fromEnum :: (a :~: b) -> Int #

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

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

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

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

a ~~ b => Enum (a :~~: b)

Since: base-4.10.0.0

Instance details

Defined in Data.Type.Equality

Methods

succ :: (a :~~: b) -> a :~~: b #

pred :: (a :~~: b) -> a :~~: b #

toEnum :: Int -> a :~~: b #

fromEnum :: (a :~~: b) -> Int #

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

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

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

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

class Eq a #

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, instances are encouraged to follow these properties:

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

Minimal complete definition: either == or /=.

Minimal complete definition

(==) | (/=)

Instances

Instances details
Eq All

Since: base-2.1

Instance details

Defined in Data.Semigroup.Internal

Methods

(==) :: All -> All -> Bool #

(/=) :: All -> All -> Bool #

Eq Any

Since: base-2.1

Instance details

Defined in Data.Semigroup.Internal

Methods

(==) :: Any -> Any -> Bool #

(/=) :: Any -> Any -> Bool #

Eq SomeTypeRep 
Instance details

Defined in Data.Typeable.Internal

Eq ErrorCall

Since: base-4.7.0.0

Instance details

Defined in GHC.Exception

Eq ArithException

Since: base-3.0

Instance details

Defined in GHC.Exception.Type

Eq SpecConstrAnnotation

Since: base-4.3.0.0

Instance details

Defined in GHC.Exts

Eq Associativity

Since: base-4.6.0.0

Instance details

Defined in GHC.Generics

Eq DecidedStrictness

Since: base-4.9.0.0

Instance details

Defined in GHC.Generics

Eq Fixity

Since: base-4.6.0.0

Instance details

Defined in GHC.Generics

Methods

(==) :: Fixity -> Fixity -> Bool #

(/=) :: Fixity -> Fixity -> Bool #

Eq SourceStrictness

Since: base-4.9.0.0

Instance details

Defined in GHC.Generics

Eq SourceUnpackedness

Since: base-4.9.0.0

Instance details

Defined in GHC.Generics

Eq MaskingState

Since: base-4.3.0.0

Instance details

Defined in GHC.IO

Eq ArrayException

Since: base-4.2.0.0

Instance details

Defined in GHC.IO.Exception

Eq AsyncException

Since: base-4.2.0.0

Instance details

Defined in GHC.IO.Exception

Eq ExitCode 
Instance details

Defined in GHC.IO.Exception

Eq IOErrorType

Since: base-4.1.0.0

Instance details

Defined in GHC.IO.Exception

Eq IOException

Since: base-4.1.0.0

Instance details

Defined in GHC.IO.Exception

Eq Int16

Since: base-2.1

Instance details

Defined in GHC.Int

Methods

(==) :: Int16 -> Int16 -> Bool #

(/=) :: Int16 -> Int16 -> Bool #

Eq Int32

Since: base-2.1

Instance details

Defined in GHC.Int

Methods

(==) :: Int32 -> Int32 -> Bool #

(/=) :: Int32 -> Int32 -> Bool #

Eq Int64

Since: base-2.1

Instance details

Defined in GHC.Int

Methods

(==) :: Int64 -> Int64 -> Bool #

(/=) :: Int64 -> Int64 -> Bool #

Eq Int8

Since: base-2.1

Instance details

Defined in GHC.Int

Methods

(==) :: Int8 -> Int8 -> Bool #

(/=) :: Int8 -> Int8 -> Bool #

Eq SrcLoc

Since: base-4.9.0.0

Instance details

Defined in GHC.Stack.Types

Methods

(==) :: SrcLoc -> SrcLoc -> Bool #

(/=) :: SrcLoc -> SrcLoc -> Bool #

Eq SomeChar 
Instance details

Defined in GHC.TypeLits

Eq SomeSymbol

Since: base-4.7.0.0

Instance details

Defined in GHC.TypeLits

Eq SomeNat

Since: base-4.7.0.0

Instance details

Defined in GHC.TypeNats

Methods

(==) :: SomeNat -> SomeNat -> Bool #

(/=) :: SomeNat -> SomeNat -> Bool #

Eq Word16

Since: base-2.1

Instance details

Defined in GHC.Word

Methods

(==) :: Word16 -> Word16 -> Bool #

(/=) :: Word16 -> Word16 -> Bool #

Eq Word32

Since: base-2.1

Instance details

Defined in GHC.Word

Methods

(==) :: Word32 -> Word32 -> Bool #

(/=) :: Word32 -> Word32 -> Bool #

Eq Word64

Since: base-2.1

Instance details

Defined in GHC.Word

Methods

(==) :: Word64 -> Word64 -> Bool #

(/=) :: Word64 -> Word64 -> Bool #

Eq Word8

Since: base-2.1

Instance details

Defined in GHC.Word

Methods

(==) :: Word8 -> Word8 -> Bool #

(/=) :: Word8 -> Word8 -> Bool #

Eq IntSet 
Instance details

Defined in Data.IntSet.Internal

Methods

(==) :: IntSet -> IntSet -> Bool #

(/=) :: IntSet -> IntSet -> Bool #

Eq SimpleType

Type equality, used to help type inference.

Instance details

Defined in Copilot.Core.Type

Eq UType 
Instance details

Defined in Copilot.Core.Type

Methods

(==) :: UType -> UType -> Bool #

(/=) :: UType -> UType -> Bool #

Eq Module 
Instance details

Defined in GHC.Classes

Methods

(==) :: Module -> Module -> Bool #

(/=) :: Module -> Module -> Bool #

Eq Ordering 
Instance details

Defined in GHC.Classes

Eq TrName 
Instance details

Defined in GHC.Classes

Methods

(==) :: TrName -> TrName -> Bool #

(/=) :: TrName -> TrName -> Bool #

Eq TyCon 
Instance details

Defined in GHC.Classes

Methods

(==) :: TyCon -> TyCon -> Bool #

(/=) :: TyCon -> TyCon -> Bool #

Eq Mode 
Instance details

Defined in Text.PrettyPrint.Annotated.HughesPJ

Methods

(==) :: Mode -> Mode -> Bool #

(/=) :: Mode -> Mode -> Bool #

Eq Style 
Instance details

Defined in Text.PrettyPrint.Annotated.HughesPJ

Methods

(==) :: Style -> Style -> Bool #

(/=) :: Style -> Style -> Bool #

Eq TextDetails 
Instance details

Defined in Text.PrettyPrint.Annotated.HughesPJ

Eq Doc 
Instance details

Defined in Text.PrettyPrint.HughesPJ

Methods

(==) :: Doc -> Doc -> Bool #

(/=) :: Doc -> Doc -> Bool #

Eq Integer 
Instance details

Defined in GHC.Num.Integer

Methods

(==) :: Integer -> Integer -> Bool #

(/=) :: Integer -> Integer -> Bool #

Eq Natural 
Instance details

Defined in GHC.Num.Natural

Methods

(==) :: Natural -> Natural -> Bool #

(/=) :: Natural -> Natural -> Bool #

Eq () 
Instance details

Defined in GHC.Classes

Methods

(==) :: () -> () -> Bool #

(/=) :: () -> () -> Bool #

Eq Bool 
Instance details

Defined in GHC.Classes

Methods

(==) :: Bool -> Bool -> Bool #

(/=) :: Bool -> Bool -> Bool #

Eq Char 
Instance details

Defined in GHC.Classes

Methods

(==) :: Char -> Char -> Bool #

(/=) :: Char -> Char -> Bool #

Eq Double

Note that due to the presence of NaN, Double's Eq instance does not satisfy reflexivity.

>>> 0/0 == (0/0 :: Double)
False

Also note that Double's Eq instance does not satisfy substitutivity:

>>> 0 == (-0 :: Double)
True
>>> recip 0 == recip (-0 :: Double)
False
Instance details

Defined in GHC.Classes

Methods

(==) :: Double -> Double -> Bool #

(/=) :: Double -> Double -> Bool #

Eq Float

Note that due to the presence of NaN, Float's Eq instance does not satisfy reflexivity.

>>> 0/0 == (0/0 :: Float)
False

Also note that Float's Eq instance does not satisfy extensionality:

>>> 0 == (-0 :: Float)
True
>>> recip 0 == recip (-0 :: Float)
False
Instance details

Defined in GHC.Classes

Methods

(==) :: Float -> Float -> Bool #

(/=) :: Float -> Float -> Bool #

Eq Int 
Instance details

Defined in GHC.Classes

Methods

(==) :: Int -> Int -> Bool #

(/=) :: Int -> Int -> Bool #

Eq Word 
Instance details

Defined in GHC.Classes

Methods

(==) :: Word -> Word -> Bool #

(/=) :: Word -> Word -> Bool #

Eq a => Eq (And a)

Since: base-4.16

Instance details

Defined in Data.Bits

Methods

(==) :: And a -> And a -> Bool #

(/=) :: And a -> And a -> Bool #

Eq a => Eq (Iff a)

Since: base-4.16

Instance details

Defined in Data.Bits

Methods

(==) :: Iff a -> Iff a -> Bool #

(/=) :: Iff a -> Iff a -> Bool #

Eq a => Eq (Ior a)

Since: base-4.16

Instance details

Defined in Data.Bits

Methods

(==) :: Ior a -> Ior a -> Bool #

(/=) :: Ior a -> Ior a -> Bool #

Eq a => Eq (Xor a)

Since: base-4.16

Instance details

Defined in Data.Bits

Methods

(==) :: Xor a -> Xor a -> Bool #

(/=) :: Xor a -> Xor a -> Bool #

Eq a => Eq (Identity a)

Since: base-4.8.0.0

Instance details

Defined in Data.Functor.Identity

Methods

(==) :: Identity a -> Identity a -> Bool #

(/=) :: Identity a -> Identity a -> Bool #

Eq a => Eq (First a)

Since: base-2.1

Instance details

Defined in Data.Monoid

Methods

(==) :: First a -> First a -> Bool #

(/=) :: First a -> First a -> Bool #

Eq a => Eq (Last a)

Since: base-2.1

Instance details

Defined in Data.Monoid

Methods

(==) :: Last a -> Last a -> Bool #

(/=) :: Last a -> Last a -> Bool #

Eq a => Eq (Down a)

Since: base-4.6.0.0

Instance details

Defined in Data.Ord

Methods

(==) :: Down a -> Down a -> Bool #

(/=) :: Down a -> Down a -> Bool #

Eq a => Eq (Dual a)

Since: base-2.1

Instance details

Defined in Data.Semigroup.Internal

Methods

(==) :: Dual a -> Dual a -> Bool #

(/=) :: Dual a -> Dual a -> Bool #

Eq a => Eq (Product a)

Since: base-2.1

Instance details

Defined in Data.Semigroup.Internal

Methods

(==) :: Product a -> Product a -> Bool #

(/=) :: Product a -> Product a -> Bool #

Eq a => Eq (Sum a)

Since: base-2.1

Instance details

Defined in Data.Semigroup.Internal

Methods

(==) :: Sum a -> Sum a -> Bool #

(/=) :: Sum a -> Sum a -> Bool #

Eq p => Eq (Par1 p)

Since: base-4.7.0.0

Instance details

Defined in GHC.Generics

Methods

(==) :: Par1 p -> Par1 p -> Bool #

(/=) :: Par1 p -> Par1 p -> Bool #

Eq (IORef a)

Pointer equality.

Since: base-4.0.0.0

Instance details

Defined in GHC.IORef

Methods

(==) :: IORef a -> IORef a -> Bool #

(/=) :: IORef a -> IORef a -> Bool #

Eq (FunPtr a) 
Instance details

Defined in GHC.Ptr

Methods

(==) :: FunPtr a -> FunPtr a -> Bool #

(/=) :: FunPtr a -> FunPtr a -> Bool #

Eq (Ptr a)

Since: base-2.1

Instance details

Defined in GHC.Ptr

Methods

(==) :: Ptr a -> Ptr a -> Bool #

(/=) :: Ptr a -> Ptr a -> Bool #

Eq a => Eq (Ratio a)

Since: base-2.1

Instance details

Defined in GHC.Real

Methods

(==) :: Ratio a -> Ratio a -> Bool #

(/=) :: Ratio a -> Ratio a -> Bool #

Eq (StableName a)

Since: base-2.1

Instance details

Defined in GHC.StableName

Methods

(==) :: StableName a -> StableName a -> Bool #

(/=) :: StableName a -> StableName a -> Bool #

Eq a => Eq (IntMap a) 
Instance details

Defined in Data.IntMap.Internal

Methods

(==) :: IntMap a -> IntMap a -> Bool #

(/=) :: IntMap a -> IntMap a -> Bool #

Eq (Stream a) Source #

Dummy instance in order to make Stream an instance of Num.

Instance details

Defined in Copilot.Language.Stream

Methods

(==) :: Stream a -> Stream a -> Bool #

(/=) :: Stream a -> Stream a -> Bool #

Eq a => Eq (DList a) 
Instance details

Defined in Data.DList.Internal

Methods

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

(/=) :: DList a -> DList a -> Bool #

Eq a => Eq (AnnotDetails a) 
Instance details

Defined in Text.PrettyPrint.Annotated.HughesPJ

Eq (Doc a) 
Instance details

Defined in Text.PrettyPrint.Annotated.HughesPJ

Methods

(==) :: Doc a -> Doc a -> Bool #

(/=) :: Doc a -> Doc a -> Bool #

Eq a => Eq (Span a) 
Instance details

Defined in Text.PrettyPrint.Annotated.HughesPJ

Methods

(==) :: Span a -> Span a -> Bool #

(/=) :: Span a -> Span a -> Bool #

Eq a => Eq (NonEmpty a)

Since: base-4.9.0.0

Instance details

Defined in GHC.Base

Methods

(==) :: NonEmpty a -> NonEmpty a -> Bool #

(/=) :: NonEmpty a -> NonEmpty a -> Bool #

Eq a => Eq (Maybe a)

Since: base-2.1

Instance details

Defined in GHC.Maybe

Methods

(==) :: Maybe a -> Maybe a -> Bool #

(/=) :: Maybe a -> Maybe a -> Bool #

Eq a => Eq (a) 
Instance details

Defined in GHC.Classes

Methods

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

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

Eq a => Eq [a] 
Instance details

Defined in GHC.Classes

Methods

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

(/=) :: [a] -> [a] -> Bool #

(Eq a, Eq b) => Eq (Either a b)

Since: base-2.1

Instance details

Defined in Data.Either

Methods

(==) :: Either a b -> Either a b -> Bool #

(/=) :: Either a b -> Either a b -> Bool #

Eq (Proxy s)

Since: base-4.7.0.0

Instance details

Defined in Data.Proxy

Methods

(==) :: Proxy s -> Proxy s -> Bool #

(/=) :: Proxy s -> Proxy s -> Bool #

Eq (TypeRep a)

Since: base-2.1

Instance details

Defined in Data.Typeable.Internal

Methods

(==) :: TypeRep a -> TypeRep a -> Bool #

(/=) :: TypeRep a -> TypeRep a -> Bool #

(Ix i, Eq e) => Eq (Array i e)

Since: base-2.1

Instance details

Defined in GHC.Arr

Methods

(==) :: Array i e -> Array i e -> Bool #

(/=) :: Array i e -> Array i e -> Bool #

Eq (U1 p)

Since: base-4.9.0.0

Instance details

Defined in GHC.Generics

Methods

(==) :: U1 p -> U1 p -> Bool #

(/=) :: U1 p -> U1 p -> Bool #

Eq (V1 p)

Since: base-4.9.0.0

Instance details

Defined in GHC.Generics

Methods

(==) :: V1 p -> V1 p -> Bool #

(/=) :: V1 p -> V1 p -> Bool #

(Eq a, Eq b) => Eq (a, b) 
Instance details

Defined in GHC.Classes

Methods

(==) :: (a, b) -> (a, b) -> Bool #

(/=) :: (a, b) -> (a, b) -> Bool #

Eq (f a) => Eq (Ap f a)

Since: base-4.12.0.0

Instance details

Defined in Data.Monoid

Methods

(==) :: Ap f a -> Ap f a -> Bool #

(/=) :: Ap f a -> Ap f a -> Bool #

Eq (f a) => Eq (Alt f a)

Since: base-4.8.0.0

Instance details

Defined in Data.Semigroup.Internal

Methods

(==) :: Alt f a -> Alt f a -> Bool #

(/=) :: Alt f a -> Alt f a -> Bool #

Eq (a :~: b)

Since: base-4.7.0.0

Instance details

Defined in Data.Type.Equality

Methods

(==) :: (a :~: b) -> (a :~: b) -> Bool #

(/=) :: (a :~: b) -> (a :~: b) -> Bool #

Eq (STArray s i e)

Since: base-2.1

Instance details

Defined in GHC.Arr

Methods

(==) :: STArray s i e -> STArray s i e -> Bool #

(/=) :: STArray s i e -> STArray s i e -> Bool #

Eq (f p) => Eq (Rec1 f p)

Since: base-4.7.0.0

Instance details

Defined in GHC.Generics

Methods

(==) :: Rec1 f p -> Rec1 f p -> Bool #

(/=) :: Rec1 f p -> Rec1 f p -> Bool #

Eq (URec (Ptr ()) p)

Since: base-4.9.0.0

Instance details

Defined in GHC.Generics

Methods

(==) :: URec (Ptr ()) p -> URec (Ptr ()) p -> Bool #

(/=) :: URec (Ptr ()) p -> URec (Ptr ()) p -> Bool #

Eq (URec Char p)

Since: base-4.9.0.0

Instance details

Defined in GHC.Generics

Methods

(==) :: URec Char p -> URec Char p -> Bool #

(/=) :: URec Char p -> URec Char p -> Bool #

Eq (URec Double p)

Since: base-4.9.0.0

Instance details

Defined in GHC.Generics

Methods

(==) :: URec Double p -> URec Double p -> Bool #

(/=) :: URec Double p -> URec Double p -> Bool #

Eq (URec Float p) 
Instance details

Defined in GHC.Generics

Methods

(==) :: URec Float p -> URec Float p -> Bool #

(/=) :: URec Float p -> URec Float p -> Bool #

Eq (URec Int p)

Since: base-4.9.0.0

Instance details

Defined in GHC.Generics

Methods

(==) :: URec Int p -> URec Int p -> Bool #

(/=) :: URec Int p -> URec Int p -> Bool #

Eq (URec Word p)

Since: base-4.9.0.0

Instance details

Defined in GHC.Generics

Methods

(==) :: URec Word p -> URec Word p -> Bool #

(/=) :: URec Word p -> URec Word p -> Bool #

(Eq e, Eq1 m, Eq a) => Eq (ErrorT e m a) 
Instance details

Defined in Control.Monad.Trans.Error

Methods

(==) :: ErrorT e m a -> ErrorT e m a -> Bool #

(/=) :: ErrorT e m a -> ErrorT e m a -> Bool #

(Eq w, Eq1 m, Eq a) => Eq (WriterT w m a) 
Instance details

Defined in Control.Monad.Trans.Writer.Lazy

Methods

(==) :: WriterT w m a -> WriterT w m a -> Bool #

(/=) :: WriterT w m a -> WriterT w m a -> Bool #

(Eq a, Eq b, Eq c) => Eq (a, b, c) 
Instance details

Defined in GHC.Classes

Methods

(==) :: (a, b, c) -> (a, b, c) -> Bool #

(/=) :: (a, b, c) -> (a, b, c) -> Bool #

Eq (a :~~: b)

Since: base-4.10.0.0

Instance details

Defined in Data.Type.Equality

Methods

(==) :: (a :~~: b) -> (a :~~: b) -> Bool #

(/=) :: (a :~~: b) -> (a :~~: b) -> Bool #

(Eq (f p), Eq (g p)) => Eq ((f :*: g) p)

Since: base-4.7.0.0

Instance details

Defined in GHC.Generics

Methods

(==) :: (f :*: g) p -> (f :*: g) p -> Bool #

(/=) :: (f :*: g) p -> (f :*: g) p -> Bool #

(Eq (f p), Eq (g p)) => Eq ((f :+: g) p)

Since: base-4.7.0.0

Instance details

Defined in GHC.Generics

Methods

(==) :: (f :+: g) p -> (f :+: g) p -> Bool #

(/=) :: (f :+: g) p -> (f :+: g) p -> Bool #

Eq c => Eq (K1 i c p)

Since: base-4.7.0.0

Instance details

Defined in GHC.Generics

Methods

(==) :: K1 i c p -> K1 i c p -> Bool #

(/=) :: K1 i c p -> K1 i c p -> Bool #

(Eq a, Eq b, Eq c, Eq d) => Eq (a, b, c, d) 
Instance details

Defined in GHC.Classes

Methods

(==) :: (a, b, c, d) -> (a, b, c, d) -> Bool #

(/=) :: (a, b, c, d) -> (a, b, c, d) -> Bool #

Eq (f (g p)) => Eq ((f :.: g) p)

Since: base-4.7.0.0

Instance details

Defined in GHC.Generics

Methods

(==) :: (f :.: g) p -> (f :.: g) p -> Bool #

(/=) :: (f :.: g) p -> (f :.: g) p -> Bool #

Eq (f p) => Eq (M1 i c f p)

Since: base-4.7.0.0

Instance details

Defined in GHC.Generics

Methods

(==) :: M1 i c f p -> M1 i c f p -> Bool #

(/=) :: M1 i c f p -> M1 i c f p -> Bool #

(Eq a, Eq b, Eq c, Eq d, Eq e) => Eq (a, b, c, d, e) 
Instance details

Defined in GHC.Classes

Methods

(==) :: (a, b, c, d, e) -> (a, b, c, d, e) -> Bool #

(/=) :: (a, b, c, d, e) -> (a, b, c, d, e) -> Bool #

(Eq a, Eq b, Eq c, Eq d, Eq e, Eq f) => Eq (a, b, c, d, e, f) 
Instance details

Defined in GHC.Classes

Methods

(==) :: (a, b, c, d, e, f) -> (a, b, c, d, e, f) -> Bool #

(/=) :: (a, b, c, d, e, f) -> (a, b, c, d, e, f) -> Bool #

(Eq a, Eq b, Eq c, Eq d, Eq e, Eq f, Eq g) => Eq (a, b, c, d, e, f, g) 
Instance details

Defined in GHC.Classes

Methods

(==) :: (a, b, c, d, e, f, g) -> (a, b, c, d, e, f, g) -> Bool #

(/=) :: (a, b, c, d, e, f, g) -> (a, b, c, d, e, f, g) -> Bool #

(Eq a, Eq b, Eq c, Eq d, Eq e, Eq f, Eq g, Eq h) => Eq (a, b, c, d, e, f, g, h) 
Instance details

Defined in GHC.Classes

Methods

(==) :: (a, b, c, d, e, f, g, h) -> (a, b, c, d, e, f, g, h) -> Bool #

(/=) :: (a, b, c, d, e, f, g, h) -> (a, b, c, d, e, f, g, h) -> Bool #

(Eq a, Eq b, Eq c, Eq d, Eq e, Eq f, Eq g, Eq h, Eq i) => Eq (a, b, c, d, e, f, g, h, i) 
Instance details

Defined in GHC.Classes

Methods

(==) :: (a, b, c, d, e, f, g, h, i) -> (a, b, c, d, e, f, g, h, i) -> Bool #

(/=) :: (a, b, c, d, e, f, g, h, i) -> (a, b, c, d, e, f, g, h, i) -> Bool #

(Eq a, Eq b, Eq c, Eq d, Eq e, Eq f, Eq g, Eq h, Eq i, Eq j) => Eq (a, b, c, d, e, f, g, h, i, j) 
Instance details

Defined in GHC.Classes

Methods

(==) :: (a, b, c, d, e, f, g, h, i, j) -> (a, b, c, d, e, f, g, h, i, j) -> Bool #

(/=) :: (a, b, c, d, e, f, g, h, i, j) -> (a, b, c, d, e, f, g, h, i, j) -> Bool #

(Eq a, Eq b, Eq c, Eq d, Eq e, Eq f, Eq g, Eq h, Eq i, Eq j, Eq k) => Eq (a, b, c, d, e, f, g, h, i, j, k) 
Instance details

Defined in GHC.Classes

Methods

(==) :: (a, b, c, d, e, f, g, h, i, j, k) -> (a, b, c, d, e, f, g, h, i, j, k) -> Bool #

(/=) :: (a, b, c, d, e, f, g, h, i, j, k) -> (a, b, c, d, e, f, g, h, i, j, k) -> Bool #

(Eq a, Eq b, Eq c, Eq d, Eq e, Eq f, Eq g, Eq h, Eq i, Eq j, Eq k, Eq l) => Eq (a, b, c, d, e, f, g, h, i, j, k, l) 
Instance details

Defined in GHC.Classes

Methods

(==) :: (a, b, c, d, e, f, g, h, i, j, k, l) -> (a, b, c, d, e, f, g, h, i, j, k, l) -> Bool #

(/=) :: (a, b, c, d, e, f, g, h, i, j, k, l) -> (a, b, c, d, e, f, g, h, i, j, k, l) -> Bool #

(Eq a, Eq b, Eq c, Eq d, Eq e, Eq f, Eq g, Eq h, Eq i, Eq j, Eq k, Eq l, Eq m) => Eq (a, b, c, d, e, f, g, h, i, j, k, l, m) 
Instance details

Defined in GHC.Classes

Methods

(==) :: (a, b, c, d, e, f, g, h, i, j, k, l, m) -> (a, b, c, d, e, f, g, h, i, j, k, l, m) -> Bool #

(/=) :: (a, b, c, d, e, f, g, h, i, j, k, l, m) -> (a, b, c, d, e, f, g, h, i, j, k, l, m) -> Bool #

(Eq a, Eq b, Eq c, Eq d, Eq e, Eq f, Eq g, Eq h, Eq i, Eq j, Eq k, Eq l, Eq m, Eq n) => Eq (a, b, c, d, e, f, g, h, i, j, k, l, m, n) 
Instance details

Defined in GHC.Classes

Methods

(==) :: (a, b, c, d, e, f, g, h, i, j, k, l, m, n) -> (a, b, c, d, e, f, g, h, i, j, k, l, m, n) -> Bool #

(/=) :: (a, b, c, d, e, f, g, h, i, j, k, l, m, n) -> (a, b, c, d, e, f, g, h, i, j, k, l, m, n) -> Bool #

(Eq a, Eq b, Eq c, Eq d, Eq e, Eq f, Eq g, Eq h, Eq i, Eq j, Eq k, Eq l, Eq m, Eq n, Eq o) => Eq (a, b, c, d, e, f, g, h, i, j, k, l, m, n, o) 
Instance details

Defined in GHC.Classes

Methods

(==) :: (a, b, c, d, e, f, g, h, i, j, k, l, m, n, o) -> (a, b, c, d, e, f, g, h, i, j, k, l, m, n, o) -> Bool #

(/=) :: (a, b, c, d, e, f, g, h, i, j, k, l, m, n, o) -> (a, b, c, d, e, f, g, h, i, j, k, l, m, n, o) -> Bool #

class Fractional a => Floating a where #

Trigonometric and hyperbolic functions and related functions.

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

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

Minimal complete definition

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

Methods

pi :: a #

exp :: a -> a #

log :: a -> a #

sqrt :: a -> a #

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

logBase :: a -> a -> a #

sin :: a -> a #

cos :: a -> a #

tan :: a -> a #

asin :: a -> a #

acos :: a -> a #

atan :: a -> a #

sinh :: a -> a #

cosh :: a -> a #

tanh :: a -> a #

asinh :: a -> a #

acosh :: a -> a #

atanh :: a -> a #

Instances

Instances details
Floating Double

Since: base-2.1

Instance details

Defined in GHC.Float

Floating Float

Since: base-2.1

Instance details

Defined in GHC.Float

Floating a => Floating (Identity a)

Since: base-4.9.0.0

Instance details

Defined in Data.Functor.Identity

Floating a => Floating (Down a)

Since: base-4.14.0.0

Instance details

Defined in Data.Ord

Methods

pi :: Down a #

exp :: Down a -> Down a #

log :: Down a -> Down a #

sqrt :: Down a -> Down a #

(**) :: Down a -> Down a -> Down a #

logBase :: Down a -> Down a -> Down a #

sin :: Down a -> Down a #

cos :: Down a -> Down a #

tan :: Down a -> Down a #

asin :: Down a -> Down a #

acos :: Down a -> Down a #

atan :: Down a -> Down a #

sinh :: Down a -> Down a #

cosh :: Down a -> Down a #

tanh :: Down a -> Down a #

asinh :: Down a -> Down a #

acosh :: Down a -> Down a #

atanh :: Down a -> Down a #

log1p :: Down a -> Down a #

expm1 :: Down a -> Down a #

log1pexp :: Down a -> Down a #

log1mexp :: Down a -> Down a #

(Typed a, Eq a, Floating a) => Floating (Stream a) Source #

Streams carrying floating point numbers are instances of Floating, and you can apply to them the Floating functions, point-wise.

Instance details

Defined in Copilot.Language.Stream

Methods

pi :: Stream a #

exp :: Stream a -> Stream a #

log :: Stream a -> Stream a #

sqrt :: Stream a -> Stream a #

(**) :: Stream a -> Stream a -> Stream a #

logBase :: Stream a -> Stream a -> Stream a #

sin :: Stream a -> Stream a #

cos :: Stream a -> Stream a #

tan :: Stream a -> Stream a #

asin :: Stream a -> Stream a #

acos :: Stream a -> Stream a #

atan :: Stream a -> Stream a #

sinh :: Stream a -> Stream a #

cosh :: Stream a -> Stream a #

tanh :: Stream a -> Stream a #

asinh :: Stream a -> Stream a #

acosh :: Stream a -> Stream a #

atanh :: Stream a -> Stream a #

log1p :: Stream a -> Stream a #

expm1 :: Stream a -> Stream a #

log1pexp :: Stream a -> Stream a #

log1mexp :: Stream a -> Stream a #

class Num a => Fractional a where #

Fractional numbers, supporting real division.

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

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

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

Minimal complete definition

fromRational, (recip | (/))

Methods

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

Fractional division.

recip :: a -> a #

Reciprocal fraction.

fromRational :: Rational -> a #

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

Instances

Instances details
Fractional a => Fractional (Identity a)

Since: base-4.9.0.0

Instance details

Defined in Data.Functor.Identity

Fractional a => Fractional (Down a)

Since: base-4.14.0.0

Instance details

Defined in Data.Ord

Methods

(/) :: Down a -> Down a -> Down a #

recip :: Down a -> Down a #

fromRational :: Rational -> Down a #

Integral a => Fractional (Ratio a)

Since: base-2.0.1

Instance details

Defined in GHC.Real

Methods

(/) :: Ratio a -> Ratio a -> Ratio a #

recip :: Ratio a -> Ratio a #

fromRational :: Rational -> Ratio a #

(Typed a, Eq a, Fractional a) => Fractional (Stream a) Source #

Streams carrying fractional numbers are instances of Fractional, and you can apply to them the Fractional functions, point-wise.

Instance details

Defined in Copilot.Language.Stream

Methods

(/) :: Stream a -> Stream a -> Stream a #

recip :: Stream a -> Stream a #

fromRational :: Rational -> Stream a #

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

Integral numbers, supporting integer division.

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

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

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

Minimal complete definition

quotRem, toInteger

Methods

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

integer division truncated toward zero

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

integer remainder, satisfying

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

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

simultaneous quot and rem

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

simultaneous div and mod

toInteger :: a -> Integer #

conversion to Integer

Instances

Instances details
Integral Int16

Since: base-2.1

Instance details

Defined in GHC.Int

Integral Int32

Since: base-2.1

Instance details

Defined in GHC.Int

Integral Int64

Since: base-2.1

Instance details

Defined in GHC.Int

Integral Int8

Since: base-2.1

Instance details

Defined in GHC.Int

Methods

quot :: Int8 -> Int8 -> Int8 #

rem :: Int8 -> Int8 -> Int8 #

div :: Int8 -> Int8 -> Int8 #

mod :: Int8 -> Int8 -> Int8 #

quotRem :: Int8 -> Int8 -> (Int8, Int8) #

divMod :: Int8 -> Int8 -> (Int8, Int8) #

toInteger :: Int8 -> Integer #

Integral Word16

Since: base-2.1

Instance details

Defined in GHC.Word

Integral Word32

Since: base-2.1

Instance details

Defined in GHC.Word

Integral Word64

Since: base-2.1

Instance details

Defined in GHC.Word

Integral Word8

Since: base-2.1

Instance details

Defined in GHC.Word

Integral Integer

Since: base-2.0.1

Instance details

Defined in GHC.Real

Integral Natural

Since: base-4.8.0.0

Instance details

Defined in GHC.Real

Integral Int

Since: base-2.0.1

Instance details

Defined in GHC.Real

Methods

quot :: Int -> Int -> Int #

rem :: Int -> Int -> Int #

div :: Int -> Int -> Int #

mod :: Int -> Int -> Int #

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

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

toInteger :: Int -> Integer #

Integral Word

Since: base-2.1

Instance details

Defined in GHC.Real

Methods

quot :: Word -> Word -> Word #

rem :: Word -> Word -> Word #

div :: Word -> Word -> Word #

mod :: Word -> Word -> Word #

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

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

toInteger :: Word -> Integer #

Integral a => Integral (Identity a)

Since: base-4.9.0.0

Instance details

Defined in Data.Functor.Identity

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

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

Instances of Monad should satisfy the following:

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

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

The above laws imply:

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

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

Minimal complete definition

(>>=)

Methods

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

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

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

do a <- as
   bs a

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

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

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

do as
   bs

return :: a -> m a #

Inject a value into the monadic type.

Instances

Instances details
Monad Identity

Since: base-4.8.0.0

Instance details

Defined in Data.Functor.Identity

Methods

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

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

return :: a -> Identity a #

Monad First

Since: base-4.8.0.0

Instance details

Defined in Data.Monoid

Methods

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

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

return :: a -> First a #

Monad Last

Since: base-4.8.0.0

Instance details

Defined in Data.Monoid

Methods

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

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

return :: a -> Last a #

Monad Down

Since: base-4.11.0.0

Instance details

Defined in Data.Ord

Methods

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

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

return :: a -> Down a #

Monad Dual

Since: base-4.8.0.0

Instance details

Defined in Data.Semigroup.Internal

Methods

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

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

return :: a -> Dual a #

Monad Product

Since: base-4.8.0.0

Instance details

Defined in Data.Semigroup.Internal

Methods

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

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

return :: a -> Product a #

Monad Sum

Since: base-4.8.0.0

Instance details

Defined in Data.Semigroup.Internal

Methods

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

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

return :: a -> Sum a #

Monad Par1

Since: base-4.9.0.0

Instance details

Defined in GHC.Generics

Methods

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

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

return :: a -> Par1 a #

Monad P

Since: base-2.1

Instance details

Defined in Text.ParserCombinators.ReadP

Methods

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

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

return :: a -> P a #

Monad ReadP

Since: base-2.1

Instance details

Defined in Text.ParserCombinators.ReadP

Methods

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

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

return :: a -> ReadP a #

Monad DList 
Instance details

Defined in Data.DList.Internal

Methods

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

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

return :: a -> DList a #

Monad IO

Since: base-2.1

Instance details

Defined in GHC.Base

Methods

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

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

return :: a -> IO a #

Monad NonEmpty

Since: base-4.9.0.0

Instance details

Defined in GHC.Base

Methods

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

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

return :: a -> NonEmpty a #

Monad Maybe

Since: base-2.1

Instance details

Defined in GHC.Base

Methods

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

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

return :: a -> Maybe a #

Monad Solo

Since: base-4.15

Instance details

Defined in GHC.Base

Methods

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

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

return :: a -> Solo a #

Monad []

Since: base-2.1

Instance details

Defined in GHC.Base

Methods

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

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

return :: a -> [a] #

Monad (Either e)

Since: base-4.4.0.0

Instance details

Defined in Data.Either

Methods

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

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

return :: a -> Either e a #

Monad (Proxy :: Type -> Type)

Since: base-4.7.0.0

Instance details

Defined in Data.Proxy

Methods

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

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

return :: a -> Proxy a #

Monad (U1 :: Type -> Type)

Since: base-4.9.0.0

Instance details

Defined in GHC.Generics

Methods

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

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

return :: a -> U1 a #

Monad (ProofScheme a) 
Instance details

Defined in Copilot.Theorem.Prove

Methods

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

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

return :: a0 -> ProofScheme a a0 #

Monoid a => Monad ((,) a)

Since: base-4.9.0.0

Instance details

Defined in GHC.Base

Methods

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

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

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

Monad f => Monad (Ap f)

Since: base-4.12.0.0

Instance details

Defined in Data.Monoid

Methods

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

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

return :: a -> Ap f a #

Monad f => Monad (Alt f)

Since: base-4.8.0.0

Instance details

Defined in Data.Semigroup.Internal

Methods

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

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

return :: a -> Alt f a #

Monad f => Monad (Rec1 f)

Since: base-4.9.0.0

Instance details

Defined in GHC.Generics

Methods

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

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

return :: a -> Rec1 f a #

(Applicative f, Monad f) => Monad (WhenMissing f x)

Equivalent to ReaderT k (ReaderT x (MaybeT f)).

Since: containers-0.5.9

Instance details

Defined in Data.IntMap.Internal

Methods

(>>=) :: WhenMissing f x a -> (a -> WhenMissing f x b) -> WhenMissing f x b #

(>>) :: WhenMissing f x a -> WhenMissing f x b -> WhenMissing f x b #

return :: a -> WhenMissing f x a #

(Monad m, Error e) => Monad (ErrorT e m) 
Instance details

Defined in Control.Monad.Trans.Error

Methods

(>>=) :: ErrorT e m a -> (a -> ErrorT e m b) -> ErrorT e m b #

(>>) :: ErrorT e m a -> ErrorT e m b -> ErrorT e m b #

return :: a -> ErrorT e m a #

(Monoid w, Monad m) => Monad (WriterT w m) 
Instance details

Defined in Control.Monad.Trans.Writer.Lazy

Methods

(>>=) :: WriterT w m a -> (a -> WriterT w m b) -> WriterT w m b #

(>>) :: WriterT w m a -> WriterT w m b -> WriterT w m b #

return :: a -> WriterT w m a #

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

Since: base-4.14.0.0

Instance details

Defined in GHC.Base

Methods

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

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

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

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

Since: base-4.9.0.0

Instance details

Defined in GHC.Generics

Methods

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

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

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

(Monad f, Applicative f) => Monad (WhenMatched f x y)

Equivalent to ReaderT Key (ReaderT x (ReaderT y (MaybeT f)))

Since: containers-0.5.9

Instance details

Defined in Data.IntMap.Internal

Methods

(>>=) :: WhenMatched f x y a -> (a -> WhenMatched f x y b) -> WhenMatched f x y b #

(>>) :: WhenMatched f x y a -> WhenMatched f x y b -> WhenMatched f x y b #

return :: a -> WhenMatched f x y a #

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

Since: base-4.14.0.0

Instance details

Defined in GHC.Base

Methods

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

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

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

Monad ((->) r)

Since: base-2.1

Instance details

Defined in GHC.Base

Methods

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

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

return :: a -> r -> a #

Monad f => Monad (M1 i c f)

Since: base-4.9.0.0

Instance details

Defined in GHC.Generics

Methods

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

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

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

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

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

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

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

Minimal complete definition

fmap

Methods

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

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 #

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

Instances

Instances details
Functor Handler

Since: base-4.6.0.0

Instance details

Defined in Control.Exception

Methods

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

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

Functor Identity

Since: base-4.8.0.0

Instance details

Defined in Data.Functor.Identity

Methods

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

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

Functor First

Since: base-4.8.0.0

Instance details

Defined in Data.Monoid

Methods

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

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

Functor Last

Since: base-4.8.0.0

Instance details

Defined in Data.Monoid

Methods

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

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

Functor Down

Since: base-4.11.0.0

Instance details

Defined in Data.Ord

Methods

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

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

Functor Dual

Since: base-4.8.0.0

Instance details

Defined in Data.Semigroup.Internal

Methods

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

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

Functor Product

Since: base-4.8.0.0

Instance details

Defined in Data.Semigroup.Internal

Methods

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

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

Functor Sum

Since: base-4.8.0.0

Instance details

Defined in Data.Semigroup.Internal

Methods

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

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

Functor Par1

Since: base-4.9.0.0

Instance details

Defined in GHC.Generics

Methods

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

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

Functor P

Since: base-4.8.0.0

Instance details

Defined in Text.ParserCombinators.ReadP

Methods

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

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

Functor ReadP

Since: base-2.1

Instance details

Defined in Text.ParserCombinators.ReadP

Methods

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

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

Functor IntMap 
Instance details

Defined in Data.IntMap.Internal

Methods

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

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

Functor DList 
Instance details

Defined in Data.DList.Internal

Methods

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

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

Functor IO

Since: base-2.1

Instance details

Defined in GHC.Base

Methods

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

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

Functor AnnotDetails 
Instance details

Defined in Text.PrettyPrint.Annotated.HughesPJ

Methods

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

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

Functor Doc 
Instance details

Defined in Text.PrettyPrint.Annotated.HughesPJ

Methods

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

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

Functor Span 
Instance details

Defined in Text.PrettyPrint.Annotated.HughesPJ

Methods

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

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

Functor NonEmpty

Since: base-4.9.0.0

Instance details

Defined in GHC.Base

Methods

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

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

Functor Maybe

Since: base-2.1

Instance details

Defined in GHC.Base

Methods

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

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

Functor Solo

Since: base-4.15

Instance details

Defined in GHC.Base

Methods

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

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

Functor []

Since: base-2.1

Instance details

Defined in GHC.Base

Methods

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

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

Functor (Either a)

Since: base-3.0

Instance details

Defined in Data.Either

Methods

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

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

Functor (Proxy :: Type -> Type)

Since: base-4.7.0.0

Instance details

Defined in Data.Proxy

Methods

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

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

Functor (Array i)

Since: base-2.1

Instance details

Defined in GHC.Arr

Methods

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

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

Functor (U1 :: Type -> Type)

Since: base-4.9.0.0

Instance details

Defined in GHC.Generics

Methods

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

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

Functor (V1 :: TYPE LiftedRep -> Type)

Since: base-4.9.0.0

Instance details

Defined in GHC.Generics

Methods

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

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

Functor (ProofScheme a) 
Instance details

Defined in Copilot.Theorem.Prove

Methods

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

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

Functor ((,) a)

Since: base-2.1

Instance details

Defined in GHC.Base

Methods

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

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

Functor f => Functor (Ap f)

Since: base-4.12.0.0

Instance details

Defined in Data.Monoid

Methods

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

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

Functor f => Functor (Alt f)

Since: base-4.8.0.0

Instance details

Defined in Data.Semigroup.Internal

Methods

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

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

Functor f => Functor (Rec1 f)

Since: base-4.9.0.0

Instance details

Defined in GHC.Generics

Methods

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

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

Functor (URec (Ptr ()) :: TYPE LiftedRep -> Type)

Since: base-4.9.0.0

Instance details

Defined in GHC.Generics

Methods

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

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

Functor (URec Char :: TYPE LiftedRep -> Type)

Since: base-4.9.0.0

Instance details

Defined in GHC.Generics

Methods

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

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

Functor (URec Double :: TYPE LiftedRep -> Type)

Since: base-4.9.0.0

Instance details

Defined in GHC.Generics

Methods

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

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

Functor (URec Float :: TYPE LiftedRep -> Type)

Since: base-4.9.0.0

Instance details

Defined in GHC.Generics

Methods

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

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

Functor (URec Int :: TYPE LiftedRep -> Type)

Since: base-4.9.0.0

Instance details

Defined in GHC.Generics

Methods

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

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

Functor (URec Word :: TYPE LiftedRep -> Type)

Since: base-4.9.0.0

Instance details

Defined in GHC.Generics

Methods

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

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

(Applicative f, Monad f) => Functor (WhenMissing f x)

Since: containers-0.5.9

Instance details

Defined in Data.IntMap.Internal

Methods

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

(<$) :: a -> WhenMissing f x b -> WhenMissing f x a #

Functor m => Functor (ErrorT e m) 
Instance details

Defined in Control.Monad.Trans.Error

Methods

fmap :: (a -> b) -> ErrorT e m a -> ErrorT e m b #

(<$) :: a -> ErrorT e m b -> ErrorT e m a #

Functor m => Functor (WriterT w m) 
Instance details

Defined in Control.Monad.Trans.Writer.Lazy

Methods

fmap :: (a -> b) -> WriterT w m a -> WriterT w m b #

(<$) :: a -> WriterT w m b -> WriterT w m a #

Functor ((,,) a b)

Since: base-4.14.0.0

Instance details

Defined in GHC.Base

Methods

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

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

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

Since: base-4.9.0.0

Instance details

Defined in GHC.Generics

Methods

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

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

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

Since: base-4.9.0.0

Instance details

Defined in GHC.Generics

Methods

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

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

Functor (K1 i c :: TYPE LiftedRep -> Type)

Since: base-4.9.0.0

Instance details

Defined in GHC.Generics

Methods

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

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

Functor f => Functor (WhenMatched f x y)

Since: containers-0.5.9

Instance details

Defined in Data.IntMap.Internal

Methods

fmap :: (a -> b) -> WhenMatched f x y a -> WhenMatched f x y b #

(<$) :: a -> WhenMatched f x y b -> WhenMatched f x y a #

Functor ((,,,) a b c)

Since: base-4.14.0.0

Instance details

Defined in GHC.Base

Methods

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

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

Functor ((->) r)

Since: base-2.1

Instance details

Defined in GHC.Base

Methods

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

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

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

Since: base-4.9.0.0

Instance details

Defined in GHC.Generics

Methods

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

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

Functor f => Functor (M1 i c f)

Since: base-4.9.0.0

Instance details

Defined in GHC.Generics

Methods

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

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

class Num a where #

Basic numeric class.

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

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

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

Minimal complete definition

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

Methods

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

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

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

negate :: a -> a #

Unary negation.

abs :: a -> a #

Absolute value.

signum :: a -> a #

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

abs x * signum x == x

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

fromInteger :: Integer -> a #

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

Instances

Instances details
Num Int16

Since: base-2.1

Instance details

Defined in GHC.Int

Num Int32

Since: base-2.1

Instance details

Defined in GHC.Int

Num Int64

Since: base-2.1

Instance details

Defined in GHC.Int

Num Int8

Since: base-2.1

Instance details

Defined in GHC.Int

Methods

(+) :: Int8 -> Int8 -> Int8 #

(-) :: Int8 -> Int8 -> Int8 #

(*) :: Int8 -> Int8 -> Int8 #

negate :: Int8 -> Int8 #

abs :: Int8 -> Int8 #

signum :: Int8 -> Int8 #

fromInteger :: Integer -> Int8 #

Num Word16

Since: base-2.1

Instance details

Defined in GHC.Word

Num Word32

Since: base-2.1

Instance details

Defined in GHC.Word

Num Word64

Since: base-2.1

Instance details

Defined in GHC.Word

Num Word8

Since: base-2.1

Instance details

Defined in GHC.Word

Num Integer

Since: base-2.1

Instance details

Defined in GHC.Num

Num Natural

Note that Natural's Num instance isn't a ring: no element but 0 has an additive inverse. It is a semiring though.

Since: base-4.8.0.0

Instance details

Defined in GHC.Num

Num Int

Since: base-2.1

Instance details

Defined in GHC.Num

Methods

(+) :: Int -> Int -> Int #

(-) :: Int -> Int -> Int #

(*) :: Int -> Int -> Int #

negate :: Int -> Int #

abs :: Int -> Int #

signum :: Int -> Int #

fromInteger :: Integer -> Int #

Num Word

Since: base-2.1

Instance details

Defined in GHC.Num

Methods

(+) :: Word -> Word -> Word #

(-) :: Word -> Word -> Word #

(*) :: Word -> Word -> Word #

negate :: Word -> Word #

abs :: Word -> Word #

signum :: Word -> Word #

fromInteger :: Integer -> Word #

Num a => Num (Identity a)

Since: base-4.9.0.0

Instance details

Defined in Data.Functor.Identity

Num a => Num (Down a)

Since: base-4.11.0.0

Instance details

Defined in Data.Ord

Methods

(+) :: Down a -> Down a -> Down a #

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

(*) :: Down a -> Down a -> Down a #

negate :: Down a -> Down a #

abs :: Down a -> Down a #

signum :: Down a -> Down a #

fromInteger :: Integer -> Down a #

Num a => Num (Product a)

Since: base-4.7.0.0

Instance details

Defined in Data.Semigroup.Internal

Methods

(+) :: Product a -> Product a -> Product a #

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

(*) :: Product a -> Product a -> Product a #

negate :: Product a -> Product a #

abs :: Product a -> Product a #

signum :: Product a -> Product a #

fromInteger :: Integer -> Product a #

Num a => Num (Sum a)

Since: base-4.7.0.0

Instance details

Defined in Data.Semigroup.Internal

Methods

(+) :: Sum a -> Sum a -> Sum a #

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

(*) :: Sum a -> Sum a -> Sum a #

negate :: Sum a -> Sum a #

abs :: Sum a -> Sum a #

signum :: Sum a -> Sum a #

fromInteger :: Integer -> Sum a #

Integral a => Num (Ratio a)

Since: base-2.0.1

Instance details

Defined in GHC.Real

Methods

(+) :: Ratio a -> Ratio a -> Ratio a #

(-) :: Ratio a -> Ratio a -> Ratio a #

(*) :: Ratio a -> Ratio a -> Ratio a #

negate :: Ratio a -> Ratio a #

abs :: Ratio a -> Ratio a #

signum :: Ratio a -> Ratio a #

fromInteger :: Integer -> Ratio a #

(Typed a, Eq a, Num a) => Num (Stream a) Source #

Streams carrying numbers are instances of Num, and you can apply to them the Num functions, point-wise.

Instance details

Defined in Copilot.Language.Stream

Methods

(+) :: Stream a -> Stream a -> Stream a #

(-) :: Stream a -> Stream a -> Stream a #

(*) :: Stream a -> Stream a -> Stream a #

negate :: Stream a -> Stream a #

abs :: Stream a -> Stream a #

signum :: Stream a -> Stream a #

fromInteger :: Integer -> Stream a #

(Applicative f, Num a) => Num (Ap f a)

Note that even if the underlying Num and Applicative instances are lawful, for most Applicatives, this instance will not be lawful. If you use this instance with the list Applicative, the following customary laws will not hold:

Commutativity:

>>> Ap [10,20] + Ap [1,2]
Ap {getAp = [11,12,21,22]}
>>> Ap [1,2] + Ap [10,20]
Ap {getAp = [11,21,12,22]}

Additive inverse:

>>> Ap [] + negate (Ap [])
Ap {getAp = []}
>>> fromInteger 0 :: Ap [] Int
Ap {getAp = [0]}

Distributivity:

>>> Ap [1,2] * (3 + 4)
Ap {getAp = [7,14]}
>>> (Ap [1,2] * 3) + (Ap [1,2] * 4)
Ap {getAp = [7,11,10,14]}

Since: base-4.12.0.0

Instance details

Defined in Data.Monoid

Methods

(+) :: Ap f a -> Ap f a -> Ap f a #

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

(*) :: Ap f a -> Ap f a -> Ap f a #

negate :: Ap f a -> Ap f a #

abs :: Ap f a -> Ap f a #

signum :: Ap f a -> Ap f a #

fromInteger :: Integer -> Ap f a #

Num (f a) => Num (Alt f a)

Since: base-4.8.0.0

Instance details

Defined in Data.Semigroup.Internal

Methods

(+) :: Alt f a -> Alt f a -> Alt f a #

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

(*) :: Alt f a -> Alt f a -> Alt f a #

negate :: Alt f a -> Alt f a #

abs :: Alt f a -> Alt f a #

signum :: Alt f a -> Alt f a #

fromInteger :: Integer -> Alt f a #

class Eq a => Ord a where #

The Ord class is used for totally ordered datatypes.

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

Ord, as defined by the Haskell report, implements a total order and has the following properties:

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

The following operator interactions are expected to hold:

  1. x >= y = y <= x
  2. x < y = x <= y && x /= y
  3. x > y = y < x
  4. x < y = compare x y == LT
  5. x > y = compare x y == GT
  6. x == y = compare x y == EQ
  7. min x y == if x <= y then x else y = True
  8. max 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.

Minimal complete definition

compare | (<=)

Methods

compare :: a -> a -> Ordering #

Instances

Instances details
Ord All

Since: base-2.1

Instance details

Defined in Data.Semigroup.Internal

Methods

compare :: All -> All -> Ordering #

(<) :: All -> All -> Bool #

(<=) :: All -> All -> Bool #

(>) :: All -> All -> Bool #

(>=) :: All -> All -> Bool #

max :: All -> All -> All #

min :: All -> All -> All #

Ord Any

Since: base-2.1

Instance details

Defined in Data.Semigroup.Internal

Methods

compare :: Any -> Any -> Ordering #

(<) :: Any -> Any -> Bool #

(<=) :: Any -> Any -> Bool #

(>) :: Any -> Any -> Bool #

(>=) :: Any -> Any -> Bool #

max :: Any -> Any -> Any #

min :: Any -> Any -> Any #

Ord SomeTypeRep 
Instance details

Defined in Data.Typeable.Internal

Ord ErrorCall

Since: base-4.7.0.0

Instance details

Defined in GHC.Exception

Ord ArithException

Since: base-3.0

Instance details

Defined in GHC.Exception.Type

Ord Associativity

Since: base-4.6.0.0

Instance details

Defined in GHC.Generics

Ord DecidedStrictness

Since: base-4.9.0.0

Instance details

Defined in GHC.Generics

Ord Fixity

Since: base-4.6.0.0

Instance details

Defined in GHC.Generics

Ord SourceStrictness

Since: base-4.9.0.0

Instance details

Defined in GHC.Generics

Ord SourceUnpackedness

Since: base-4.9.0.0

Instance details

Defined in GHC.Generics

Ord ArrayException

Since: base-4.2.0.0

Instance details

Defined in GHC.IO.Exception

Ord AsyncException

Since: base-4.2.0.0

Instance details

Defined in GHC.IO.Exception

Ord ExitCode 
Instance details

Defined in GHC.IO.Exception

Ord Int16

Since: base-2.1

Instance details

Defined in GHC.Int

Methods

compare :: Int16 -> Int16 -> Ordering #

(<) :: Int16 -> Int16 -> Bool #

(<=) :: Int16 -> Int16 -> Bool #

(>) :: Int16 -> Int16 -> Bool #

(>=) :: Int16 -> Int16 -> Bool #

max :: Int16 -> Int16 -> Int16 #

min :: Int16 -> Int16 -> Int16 #

Ord Int32

Since: base-2.1

Instance details

Defined in GHC.Int

Methods

compare :: Int32 -> Int32 -> Ordering #

(<) :: Int32 -> Int32 -> Bool #

(<=) :: Int32 -> Int32 -> Bool #

(>) :: Int32 -> Int32 -> Bool #

(>=) :: Int32 -> Int32 -> Bool #

max :: Int32 -> Int32 -> Int32 #

min :: Int32 -> Int32 -> Int32 #

Ord Int64

Since: base-2.1

Instance details

Defined in GHC.Int

Methods

compare :: Int64 -> Int64 -> Ordering #

(<) :: Int64 -> Int64 -> Bool #

(<=) :: Int64 -> Int64 -> Bool #

(>) :: Int64 -> Int64 -> Bool #

(>=) :: Int64 -> Int64 -> Bool #

max :: Int64 -> Int64 -> Int64 #

min :: Int64 -> Int64 -> Int64 #

Ord Int8

Since: base-2.1

Instance details

Defined in GHC.Int

Methods

compare :: Int8 -> Int8 -> Ordering #

(<) :: Int8 -> Int8 -> Bool #

(<=) :: Int8 -> Int8 -> Bool #

(>) :: Int8 -> Int8 -> Bool #

(>=) :: Int8 -> Int8 -> Bool #

max :: Int8 -> Int8 -> Int8 #

min :: Int8 -> Int8 -> Int8 #

Ord SomeChar 
Instance details

Defined in GHC.TypeLits

Ord SomeSymbol

Since: base-4.7.0.0

Instance details

Defined in GHC.TypeLits

Ord SomeNat

Since: base-4.7.0.0

Instance details

Defined in GHC.TypeNats

Ord Word16

Since: base-2.1

Instance details

Defined in GHC.Word

Ord Word32

Since: base-2.1

Instance details

Defined in GHC.Word

Ord Word64

Since: base-2.1

Instance details

Defined in GHC.Word

Ord Word8

Since: base-2.1

Instance details

Defined in GHC.Word

Methods

compare :: Word8 -> Word8 -> Ordering #

(<) :: Word8 -> Word8 -> Bool #

(<=) :: Word8 -> Word8 -> Bool #

(>) :: Word8 -> Word8 -> Bool #

(>=) :: Word8 -> Word8 -> Bool #

max :: Word8 -> Word8 -> Word8 #

min :: Word8 -> Word8 -> Word8 #

Ord IntSet 
Instance details

Defined in Data.IntSet.Internal

Ord Ordering 
Instance details

Defined in GHC.Classes

Ord TyCon 
Instance details

Defined in GHC.Classes

Methods

compare :: TyCon -> TyCon -> Ordering #

(<) :: TyCon -> TyCon -> Bool #

(<=) :: TyCon -> TyCon -> Bool #

(>) :: TyCon -> TyCon -> Bool #

(>=) :: TyCon -> TyCon -> Bool #

max :: TyCon -> TyCon -> TyCon #

min :: TyCon -> TyCon -> TyCon #

Ord Integer 
Instance details

Defined in GHC.Num.Integer

Ord Natural 
Instance details

Defined in GHC.Num.Natural

Ord () 
Instance details

Defined in GHC.Classes

Methods

compare :: () -> () -> Ordering #

(<) :: () -> () -> Bool #

(<=) :: () -> () -> Bool #

(>) :: () -> () -> Bool #

(>=) :: () -> () -> Bool #

max :: () -> () -> () #

min :: () -> () -> () #

Ord Bool 
Instance details

Defined in GHC.Classes

Methods

compare :: Bool -> Bool -> Ordering #

(<) :: Bool -> Bool -> Bool #

(<=) :: Bool -> Bool -> Bool #

(>) :: Bool -> Bool -> Bool #

(>=) :: Bool -> Bool -> Bool #

max :: Bool -> Bool -> Bool #

min :: Bool -> Bool -> Bool #

Ord Char 
Instance details

Defined in GHC.Classes

Methods

compare :: Char -> Char -> Ordering #

(<) :: Char -> Char -> Bool #

(<=) :: Char -> Char -> Bool #

(>) :: Char -> Char -> Bool #

(>=) :: Char -> Char -> Bool #

max :: Char -> Char -> Char #

min :: Char -> Char -> Char #

Ord Double

Note that due to the presence of NaN, Double's Ord instance does not satisfy reflexivity.

>>> 0/0 <= (0/0 :: Double)
False

Also note that, due to the same, Ord's operator interactions are not respected by Double's instance:

>>> (0/0 :: Double) > 1
False
>>> compare (0/0 :: Double) 1
GT
Instance details

Defined in GHC.Classes

Ord Float

Note that due to the presence of NaN, Float's Ord instance does not satisfy reflexivity.

>>> 0/0 <= (0/0 :: Float)
False

Also note that, due to the same, Ord's operator interactions are not respected by Float's instance:

>>> (0/0 :: Float) > 1
False
>>> compare (0/0 :: Float) 1
GT
Instance details

Defined in GHC.Classes

Methods

compare :: Float -> Float -> Ordering #

(<) :: Float -> Float -> Bool #

(<=) :: Float -> Float -> Bool #

(>) :: Float -> Float -> Bool #

(>=) :: Float -> Float -> Bool #

max :: Float -> Float -> Float #

min :: Float -> Float -> Float #

Ord Int 
Instance details

Defined in GHC.Classes

Methods

compare :: Int -> Int -> Ordering #

(<) :: Int -> Int -> Bool #

(<=) :: Int -> Int -> Bool #

(>) :: Int -> Int -> Bool #

(>=) :: Int -> Int -> Bool #

max :: Int -> Int -> Int #

min :: Int -> Int -> Int #

Ord Word 
Instance details

Defined in GHC.Classes

Methods

compare :: Word -> Word -> Ordering #

(<) :: Word -> Word -> Bool #

(<=) :: Word -> Word -> Bool #

(>) :: Word -> Word -> Bool #

(>=) :: Word -> Word -> Bool #

max :: Word -> Word -> Word #

min :: Word -> Word -> Word #

Ord a => Ord (Identity a)

Since: base-4.8.0.0

Instance details

Defined in Data.Functor.Identity

Methods

compare :: Identity a -> Identity a -> Ordering #

(<) :: Identity a -> Identity a -> Bool #

(<=) :: Identity a -> Identity a -> Bool #

(>) :: Identity a -> Identity a -> Bool #

(>=) :: Identity a -> Identity a -> Bool #

max :: Identity a -> Identity a -> Identity a #

min :: Identity a -> Identity a -> Identity a #

Ord a => Ord (First a)

Since: base-2.1

Instance details

Defined in Data.Monoid

Methods

compare :: First a -> First a -> Ordering #

(<) :: First a -> First a -> Bool #

(<=) :: First a -> First a -> Bool #

(>) :: First a -> First a -> Bool #

(>=) :: First a -> First a -> Bool #

max :: First a -> First a -> First a #

min :: First a -> First a -> First a #

Ord a => Ord (Last a)

Since: base-2.1

Instance details

Defined in Data.Monoid

Methods

compare :: Last a -> Last a -> Ordering #

(<) :: Last a -> Last a -> Bool #

(<=) :: Last a -> Last a -> Bool #

(>) :: Last a -> Last a -> Bool #

(>=) :: Last a -> Last a -> Bool #

max :: Last a -> Last a -> Last a #

min :: Last a -> Last a -> Last a #

Ord a => Ord (Down a)

Since: base-4.6.0.0

Instance details

Defined in Data.Ord

Methods

compare :: Down a -> Down a -> Ordering #

(<) :: Down a -> Down a -> Bool #

(<=) :: Down a -> Down a -> Bool #

(>) :: Down a -> Down a -> Bool #

(>=) :: Down a -> Down a -> Bool #

max :: Down a -> Down a -> Down a #

min :: Down a -> Down a -> Down a #

Ord a => Ord (Dual a)

Since: base-2.1

Instance details

Defined in Data.Semigroup.Internal

Methods

compare :: Dual a -> Dual a -> Ordering #

(<) :: Dual a -> Dual a -> Bool #

(<=) :: Dual a -> Dual a -> Bool #

(>) :: Dual a -> Dual a -> Bool #

(>=) :: Dual a -> Dual a -> Bool #

max :: Dual a -> Dual a -> Dual a #

min :: Dual a -> Dual a -> Dual a #

Ord a => Ord (Product a)

Since: base-2.1

Instance details

Defined in Data.Semigroup.Internal

Methods

compare :: Product a -> Product a -> Ordering #

(<) :: Product a -> Product a -> Bool #

(<=) :: Product a -> Product a -> Bool #

(>) :: Product a -> Product a -> Bool #

(>=) :: Product a -> Product a -> Bool #

max :: Product a -> Product a -> Product a #

min :: Product a -> Product a -> Product a #

Ord a => Ord (Sum a)

Since: base-2.1

Instance details

Defined in Data.Semigroup.Internal

Methods

compare :: Sum a -> Sum a -> Ordering #

(<) :: Sum a -> Sum a -> Bool #

(<=) :: Sum a -> Sum a -> Bool #

(>) :: Sum a -> Sum a -> Bool #

(>=) :: Sum a -> Sum a -> Bool #

max :: Sum a -> Sum a -> Sum a #

min :: Sum a -> Sum a -> Sum a #

Ord p => Ord (Par1 p)

Since: base-4.7.0.0

Instance details

Defined in GHC.Generics

Methods

compare :: Par1 p -> Par1 p -> Ordering #

(<) :: Par1 p -> Par1 p -> Bool #

(<=) :: Par1 p -> Par1 p -> Bool #

(>) :: Par1 p -> Par1 p -> Bool #

(>=) :: Par1 p -> Par1 p -> Bool #

max :: Par1 p -> Par1 p -> Par1 p #

min :: Par1 p -> Par1 p -> Par1 p #

Ord (FunPtr a) 
Instance details

Defined in GHC.Ptr

Methods

compare :: FunPtr a -> FunPtr a -> Ordering #

(<) :: FunPtr a -> FunPtr a -> Bool #

(<=) :: FunPtr a -> FunPtr a -> Bool #

(>) :: FunPtr a -> FunPtr a -> Bool #

(>=) :: FunPtr a -> FunPtr a -> Bool #

max :: FunPtr a -> FunPtr a -> FunPtr a #

min :: FunPtr a -> FunPtr a -> FunPtr a #

Ord (Ptr a)

Since: base-2.1

Instance details

Defined in GHC.Ptr

Methods

compare :: Ptr a -> Ptr a -> Ordering #

(<) :: Ptr a -> Ptr a -> Bool #

(<=) :: Ptr a -> Ptr a -> Bool #

(>) :: Ptr a -> Ptr a -> Bool #

(>=) :: Ptr a -> Ptr a -> Bool #

max :: Ptr a -> Ptr a -> Ptr a #

min :: Ptr a -> Ptr a -> Ptr a #

Integral a => Ord (Ratio a)

Since: base-2.0.1

Instance details

Defined in GHC.Real

Methods

compare :: Ratio a -> Ratio a -> Ordering #

(<) :: Ratio a -> Ratio a -> Bool #

(<=) :: Ratio a -> Ratio a -> Bool #

(>) :: Ratio a -> Ratio a -> Bool #

(>=) :: Ratio a -> Ratio a -> Bool #

max :: Ratio a -> Ratio a -> Ratio a #

min :: Ratio a -> Ratio a -> Ratio a #

Ord a => Ord (IntMap a) 
Instance details

Defined in Data.IntMap.Internal

Methods

compare :: IntMap a -> IntMap a -> Ordering #

(<) :: IntMap a -> IntMap a -> Bool #

(<=) :: IntMap a -> IntMap a -> Bool #

(>) :: IntMap a -> IntMap a -> Bool #

(>=) :: IntMap a -> IntMap a -> Bool #

max :: IntMap a -> IntMap a -> IntMap a #

min :: IntMap a -> IntMap a -> IntMap a #

Ord a => Ord (DList a) 
Instance details

Defined in Data.DList.Internal

Methods

compare :: DList a -> DList a -> Ordering #

(<) :: DList a -> DList a -> Bool #

(<=) :: DList a -> DList a -> Bool #

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

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

max :: DList a -> DList a -> DList a #

min :: DList a -> DList a -> DList a #

Ord a => Ord (NonEmpty a)

Since: base-4.9.0.0

Instance details

Defined in GHC.Base

Methods

compare :: NonEmpty a -> NonEmpty a -> Ordering #

(<) :: NonEmpty a -> NonEmpty a -> Bool #

(<=) :: NonEmpty a -> NonEmpty a -> Bool #

(>) :: NonEmpty a -> NonEmpty a -> Bool #

(>=) :: NonEmpty a -> NonEmpty a -> Bool #

max :: NonEmpty a -> NonEmpty a -> NonEmpty a #

min :: NonEmpty a -> NonEmpty a -> NonEmpty a #

Ord a => Ord (Maybe a)

Since: base-2.1

Instance details

Defined in GHC.Maybe

Methods

compare :: Maybe a -> Maybe a -> Ordering #

(<) :: Maybe a -> Maybe a -> Bool #

(<=) :: Maybe a -> Maybe a -> Bool #

(>) :: Maybe a -> Maybe a -> Bool #

(>=) :: Maybe a -> Maybe a -> Bool #

max :: Maybe a -> Maybe a -> Maybe a #

min :: Maybe a -> Maybe a -> Maybe a #

Ord a => Ord (a) 
Instance details

Defined in GHC.Classes

Methods

compare :: (a) -> (a) -> Ordering #

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

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

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

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

max :: (a) -> (a) -> (a) #

min :: (a) -> (a) -> (a) #

Ord a => Ord [a] 
Instance details

Defined in GHC.Classes

Methods

compare :: [a] -> [a] -> Ordering #

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

(<=) :: [a] -> [a] -> Bool #

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

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

max :: [a] -> [a] -> [a] #

min :: [a] -> [a] -> [a] #

(Ord a, Ord b) => Ord (Either a b)

Since: base-2.1

Instance details

Defined in Data.Either

Methods

compare :: Either a b -> Either a b -> Ordering #

(<) :: Either a b -> Either a b -> Bool #

(<=) :: Either a b -> Either a b -> Bool #

(>) :: Either a b -> Either a b -> Bool #

(>=) :: Either a b -> Either a b -> Bool #

max :: Either a b -> Either a b -> Either a b #

min :: Either a b -> Either a b -> Either a b #

Ord (Proxy s)

Since: base-4.7.0.0

Instance details

Defined in Data.Proxy

Methods

compare :: Proxy s -> Proxy s -> Ordering #

(<) :: Proxy s -> Proxy s -> Bool #

(<=) :: Proxy s -> Proxy s -> Bool #

(>) :: Proxy s -> Proxy s -> Bool #

(>=) :: Proxy s -> Proxy s -> Bool #

max :: Proxy s -> Proxy s -> Proxy s #

min :: Proxy s -> Proxy s -> Proxy s #

Ord (TypeRep a)

Since: base-4.4.0.0

Instance details

Defined in Data.Typeable.Internal

Methods

compare :: TypeRep a -> TypeRep a -> Ordering #

(<) :: TypeRep a -> TypeRep a -> Bool #

(<=) :: TypeRep a -> TypeRep a -> Bool #

(>) :: TypeRep a -> TypeRep a -> Bool #

(>=) :: TypeRep a -> TypeRep a -> Bool #

max :: TypeRep a -> TypeRep a -> TypeRep a #

min :: TypeRep a -> TypeRep a -> TypeRep a #

(Ix i, Ord e) => Ord (Array i e)

Since: base-2.1

Instance details

Defined in GHC.Arr

Methods

compare :: Array i e -> Array i e -> Ordering #

(<) :: Array i e -> Array i e -> Bool #

(<=) :: Array i e -> Array i e -> Bool #

(>) :: Array i e -> Array i e -> Bool #

(>=) :: Array i e -> Array i e -> Bool #

max :: Array i e -> Array i e -> Array i e #

min :: Array i e -> Array i e -> Array i e #

Ord (U1 p)

Since: base-4.7.0.0

Instance details

Defined in GHC.Generics

Methods

compare :: U1 p -> U1 p -> Ordering #

(<) :: U1 p -> U1 p -> Bool #

(<=) :: U1 p -> U1 p -> Bool #

(>) :: U1 p -> U1 p -> Bool #

(>=) :: U1 p -> U1 p -> Bool #

max :: U1 p -> U1 p -> U1 p #

min :: U1 p -> U1 p -> U1 p #

Ord (V1 p)

Since: base-4.9.0.0

Instance details

Defined in GHC.Generics

Methods

compare :: V1 p -> V1 p -> Ordering #

(<) :: V1 p -> V1 p -> Bool #

(<=) :: V1 p -> V1 p -> Bool #

(>) :: V1 p -> V1 p -> Bool #

(>=) :: V1 p -> V1 p -> Bool #

max :: V1 p -> V1 p -> V1 p #

min :: V1 p -> V1 p -> V1 p #

(Ord a, Ord b) => Ord (a, b) 
Instance details

Defined in GHC.Classes

Methods

compare :: (a, b) -> (a, b) -> Ordering #

(<) :: (a, b) -> (a, b) -> Bool #

(<=) :: (a, b) -> (a, b) -> Bool #

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

(>=) :: (a, b) -> (a, b) -> Bool #

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

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

Ord (f a) => Ord (Ap f a)

Since: base-4.12.0.0

Instance details

Defined in Data.Monoid

Methods

compare :: Ap f a -> Ap f a -> Ordering #

(<) :: Ap f a -> Ap f a -> Bool #

(<=) :: Ap f a -> Ap f a -> Bool #

(>) :: Ap f a -> Ap f a -> Bool #

(>=) :: Ap f a -> Ap f a -> Bool #

max :: Ap f a -> Ap f a -> Ap f a #

min :: Ap f a -> Ap f a -> Ap f a #

Ord (f a) => Ord (Alt f a)

Since: base-4.8.0.0

Instance details

Defined in Data.Semigroup.Internal

Methods

compare :: Alt f a -> Alt f a -> Ordering #

(<) :: Alt f a -> Alt f a -> Bool #

(<=) :: Alt f a -> Alt f a -> Bool #

(>) :: Alt f a -> Alt f a -> Bool #

(>=) :: Alt f a -> Alt f a -> Bool #

max :: Alt f a -> Alt f a -> Alt f a #

min :: Alt f a -> Alt f a -> Alt f a #

Ord (a :~: b)

Since: base-4.7.0.0

Instance details

Defined in Data.Type.Equality

Methods

compare :: (a :~: b) -> (a :~: b) -> Ordering #

(<) :: (a :~: b) -> (a :~: b) -> Bool #

(<=) :: (a :~: b) -> (a :~: b) -> Bool #

(>) :: (a :~: b) -> (a :~: b) -> Bool #

(>=) :: (a :~: b) -> (a :~: b) -> Bool #

max :: (a :~: b) -> (a :~: b) -> a :~: b #

min :: (a :~: b) -> (a :~: b) -> a :~: b #

Ord (f p) => Ord (Rec1 f p)

Since: base-4.7.0.0

Instance details

Defined in GHC.Generics

Methods

compare :: Rec1 f p -> Rec1 f p -> Ordering #

(<) :: Rec1 f p -> Rec1 f p -> Bool #

(<=) :: Rec1 f p -> Rec1 f p -> Bool #

(>) :: Rec1 f p -> Rec1 f p -> Bool #

(>=) :: Rec1 f p -> Rec1 f p -> Bool #

max :: Rec1 f p -> Rec1 f p -> Rec1 f p #

min :: Rec1 f p -> Rec1 f p -> Rec1 f p #

Ord (URec (Ptr ()) p)

Since: base-4.9.0.0

Instance details

Defined in GHC.Generics

Methods

compare :: URec (Ptr ()) p -> URec (Ptr ()) p -> Ordering #

(<) :: URec (Ptr ()) p -> URec (Ptr ()) p -> Bool #

(<=) :: URec (Ptr ()) p -> URec (Ptr ()) p -> Bool #

(>) :: URec (Ptr ()) p -> URec (Ptr ()) p -> Bool #

(>=) :: URec (Ptr ()) p -> URec (Ptr ()) p -> Bool #

max :: URec (Ptr ()) p -> URec (Ptr ()) p -> URec (Ptr ()) p #

min :: URec (Ptr ()) p -> URec (Ptr ()) p -> URec (Ptr ()) p #

Ord (URec Char p)

Since: base-4.9.0.0

Instance details

Defined in GHC.Generics

Methods

compare :: URec Char p -> URec Char p -> Ordering #

(<) :: URec Char p -> URec Char p -> Bool #

(<=) :: URec Char p -> URec Char p -> Bool #

(>) :: URec Char p -> URec Char p -> Bool #

(>=) :: URec Char p -> URec Char p -> Bool #

max :: URec Char p -> URec Char p -> URec Char p #

min :: URec Char p -> URec Char p -> URec Char p #

Ord (URec Double p)

Since: base-4.9.0.0

Instance details

Defined in GHC.Generics

Methods

compare :: URec Double p -> URec Double p -> Ordering #

(<) :: URec Double p -> URec Double p -> Bool #

(<=) :: URec Double p -> URec Double p -> Bool #

(>) :: URec Double p -> URec Double p -> Bool #

(>=) :: URec Double p -> URec Double p -> Bool #

max :: URec Double p -> URec Double p -> URec Double p #

min :: URec Double p -> URec Double p -> URec Double p #

Ord (URec Float p) 
Instance details

Defined in GHC.Generics

Methods

compare :: URec Float p -> URec Float p -> Ordering #

(<) :: URec Float p -> URec Float p -> Bool #

(<=) :: URec Float p -> URec Float p -> Bool #

(>) :: URec Float p -> URec Float p -> Bool #

(>=) :: URec Float p -> URec Float p -> Bool #

max :: URec Float p -> URec Float p -> URec Float p #

min :: URec Float p -> URec Float p -> URec Float p #

Ord (URec Int p)

Since: base-4.9.0.0

Instance details

Defined in GHC.Generics

Methods

compare :: URec Int p -> URec Int p -> Ordering #

(<) :: URec Int p -> URec Int p -> Bool #

(<=) :: URec Int p -> URec Int p -> Bool #

(>) :: URec Int p -> URec Int p -> Bool #

(>=) :: URec Int p -> URec Int p -> Bool #

max :: URec Int p -> URec Int p -> URec Int p #

min :: URec Int p -> URec Int p -> URec Int p #

Ord (URec Word p)

Since: base-4.9.0.0

Instance details

Defined in GHC.Generics

Methods

compare :: URec Word p -> URec Word p -> Ordering #

(<) :: URec Word p -> URec Word p -> Bool #

(<=) :: URec Word p -> URec Word p -> Bool #

(>) :: URec Word p -> URec Word p -> Bool #

(>=) :: URec Word p -> URec Word p -> Bool #

max :: URec Word p -> URec Word p -> URec Word p #

min :: URec Word p -> URec Word p -> URec Word p #

(Ord e, Ord1 m, Ord a) => Ord (ErrorT e m a) 
Instance details

Defined in Control.Monad.Trans.Error

Methods

compare :: ErrorT e m a -> ErrorT e m a -> Ordering #

(<) :: ErrorT e m a -> ErrorT e m a -> Bool #

(<=) :: ErrorT e m a -> ErrorT e m a -> Bool #

(>) :: ErrorT e m a -> ErrorT e m a -> Bool #

(>=) :: ErrorT e m a -> ErrorT e m a -> Bool #

max :: ErrorT e m a -> ErrorT e m a -> ErrorT e m a #

min :: ErrorT e m a -> ErrorT e m a -> ErrorT e m a #

(Ord w, Ord1 m, Ord a) => Ord (WriterT w m a) 
Instance details

Defined in Control.Monad.Trans.Writer.Lazy

Methods

compare :: WriterT w m a -> WriterT w m a -> Ordering #

(<) :: WriterT w m a -> WriterT w m a -> Bool #

(<=) :: WriterT w m a -> WriterT w m a -> Bool #

(>) :: WriterT w m a -> WriterT w m a -> Bool #

(>=) :: WriterT w m a -> WriterT w m a -> Bool #

max :: WriterT w m a -> WriterT w m a -> WriterT w m a #

min :: WriterT w m a -> WriterT w m a -> WriterT w m a #

(Ord a, Ord b, Ord c) => Ord (a, b, c) 
Instance details

Defined in GHC.Classes

Methods

compare :: (a, b, c) -> (a, b, c) -> Ordering #

(<) :: (a, b, c) -> (a, b, c) -> Bool #

(<=) :: (a, b, c) -> (a, b, c) -> Bool #

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

(>=) :: (a, b, c) -> (a, b, c) -> Bool #

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

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

Ord (a :~~: b)

Since: base-4.10.0.0

Instance details

Defined in Data.Type.Equality

Methods

compare :: (a :~~: b) -> (a :~~: b) -> Ordering #

(<) :: (a :~~: b) -> (a :~~: b) -> Bool #

(<=) :: (a :~~: b) -> (a :~~: b) -> Bool #

(>) :: (a :~~: b) -> (a :~~: b) -> Bool #

(>=) :: (a :~~: b) -> (a :~~: b) -> Bool #

max :: (a :~~: b) -> (a :~~: b) -> a :~~: b #

min :: (a :~~: b) -> (a :~~: b) -> a :~~: b #

(Ord (f p), Ord (g p)) => Ord ((f :*: g) p)

Since: base-4.7.0.0

Instance details

Defined in GHC.Generics

Methods

compare :: (f :*: g) p -> (f :*: g) p -> Ordering #

(<) :: (f :*: g) p -> (f :*: g) p -> Bool #

(<=) :: (f :*: g) p -> (f :*: g) p -> Bool #

(>) :: (f :*: g) p -> (f :*: g) p -> Bool #

(>=) :: (f :*: g) p -> (f :*: g) p -> Bool #

max :: (f :*: g) p -> (f :*: g) p -> (f :*: g) p #

min :: (f :*: g) p -> (f :*: g) p -> (f :*: g) p #

(Ord (f p), Ord (g p)) => Ord ((f :+: g) p)

Since: base-4.7.0.0

Instance details

Defined in GHC.Generics

Methods

compare :: (f :+: g) p -> (f :+: g) p -> Ordering #

(<) :: (f :+: g) p -> (f :+: g) p -> Bool #

(<=) :: (f :+: g) p -> (f :+: g) p -> Bool #

(>) :: (f :+: g) p -> (f :+: g) p -> Bool #

(>=) :: (f :+: g) p -> (f :+: g) p -> Bool #

max :: (f :+: g) p -> (f :+: g) p -> (f :+: g) p #

min :: (f :+: g) p -> (f :+: g) p -> (f :+: g) p #

Ord c => Ord (K1 i c p)

Since: base-4.7.0.0

Instance details

Defined in GHC.Generics

Methods

compare :: K1 i c p -> K1 i c p -> Ordering #

(<) :: K1 i c p -> K1 i c p -> Bool #

(<=) :: K1 i c p -> K1 i c p -> Bool #

(>) :: K1 i c p -> K1 i c p -> Bool #

(>=) :: K1 i c p -> K1 i c p -> Bool #

max :: K1 i c p -> K1 i c p -> K1 i c p #

min :: K1 i c p -> K1 i c p -> K1 i c p #

(Ord a, Ord b, Ord c, Ord d) => Ord (a, b, c, d) 
Instance details

Defined in GHC.Classes

Methods

compare :: (a, b, c, d) -> (a, b, c, d) -> Ordering #

(<) :: (a, b, c, d) -> (a, b, c, d) -> Bool #

(<=) :: (a, b, c, d) -> (a, b, c, d) -> Bool #

(>) :: (a, b, c, d) -> (a, b, c, d) -> Bool #

(>=) :: (a, b, c, d) -> (a, b, c, d) -> Bool #

max :: (a, b, c, d) -> (a, b, c, d) -> (a, b, c, d) #

min :: (a, b, c, d) -> (a, b, c, d) -> (a, b, c, d) #

Ord (f (g p)) => Ord ((f :.: g) p)

Since: base-4.7.0.0

Instance details

Defined in GHC.Generics

Methods

compare :: (f :.: g) p -> (f :.: g) p -> Ordering #

(<) :: (f :.: g) p -> (f :.: g) p -> Bool #

(<=) :: (f :.: g) p -> (f :.: g) p -> Bool #

(>) :: (f :.: g) p -> (f :.: g) p -> Bool #

(>=) :: (f :.: g) p -> (f :.: g) p -> Bool #

max :: (f :.: g) p -> (f :.: g) p -> (f :.: g) p #

min :: (f :.: g) p -> (f :.: g) p -> (f :.: g) p #

Ord (f p) => Ord (M1 i c f p)

Since: base-4.7.0.0

Instance details

Defined in GHC.Generics

Methods

compare :: M1 i c f p -> M1 i c f p -> Ordering #

(<) :: M1 i c f p -> M1 i c f p -> Bool #

(<=) :: M1 i c f p -> M1 i c f p -> Bool #

(>) :: M1 i c f p -> M1 i c f p -> Bool #

(>=) :: M1 i c f p -> M1 i c f p -> Bool #

max :: M1 i c f p -> M1 i c f p -> M1 i c f p #

min :: M1 i c f p -> M1 i c f p -> M1 i c f p #

(Ord a, Ord b, Ord c, Ord d, Ord e) => Ord (a, b, c, d, e) 
Instance details

Defined in GHC.Classes

Methods

compare :: (a, b, c, d, e) -> (a, b, c, d, e) -> Ordering #

(<) :: (a, b, c, d, e) -> (a, b, c, d, e) -> Bool #

(<=) :: (a, b, c, d, e) -> (a, b, c, d, e) -> Bool #

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

(>=) :: (a, b, c, d, e) -> (a, b, c, d, e) -> Bool #

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

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

(Ord a, Ord b, Ord c, Ord d, Ord e, Ord f) => Ord (a, b, c, d, e, f) 
Instance details

Defined in GHC.Classes

Methods

compare :: (a, b, c, d, e, f) -> (a, b, c, d, e, f) -> Ordering #

(<) :: (a, b, c, d, e, f) -> (a, b, c, d, e, f) -> Bool #

(<=) :: (a, b, c, d, e, f) -> (a, b, c, d, e, f) -> Bool #

(>) :: (a, b, c, d, e, f) -> (a, b, c, d, e, f) -> Bool #

(>=) :: (a, b, c, d, e, f) -> (a, b, c, d, e, f) -> Bool #

max :: (a, b, c, d, e, f) -> (a, b, c, d, e, f) -> (a, b, c, d, e, f) #

min :: (a, b, c, d, e, f) -> (a, b, c, d, e, f) -> (a, b, c, d, e, f) #

(Ord a, Ord b, Ord c, Ord d, Ord e, Ord f, Ord g) => Ord (a, b, c, d, e, f, g) 
Instance details

Defined in GHC.Classes

Methods

compare :: (a, b, c, d, e, f, g) -> (a, b, c, d, e, f, g) -> Ordering #

(<) :: (a, b, c, d, e, f, g) -> (a, b, c, d, e, f, g) -> Bool #

(<=) :: (a, b, c, d, e, f, g) -> (a, b, c, d, e, f, g) -> Bool #

(>) :: (a, b, c, d, e, f, g) -> (a, b, c, d, e, f, g) -> Bool #

(>=) :: (a, b, c, d, e, f, g) -> (a, b, c, d, e, f, g) -> Bool #

max :: (a, b, c, d, e, f, g) -> (a, b, c, d, e, f, g) -> (a, b, c, d, e, f, g) #

min :: (a, b, c, d, e, f, g) -> (a, b, c, d, e, f, g) -> (a, b, c, d, e, f, g) #

(Ord a, Ord b, Ord c, Ord d, Ord e, Ord f, Ord g, Ord h) => Ord (a, b, c, d, e, f, g, h) 
Instance details

Defined in GHC.Classes

Methods

compare :: (a, b, c, d, e, f, g, h) -> (a, b, c, d, e, f, g, h) -> Ordering #

(<) :: (a, b, c, d, e, f, g, h) -> (a, b, c, d, e, f, g, h) -> Bool #

(<=) :: (a, b, c, d, e, f, g, h) -> (a, b, c, d, e, f, g, h) -> Bool #

(>) :: (a, b, c, d, e, f, g, h) -> (a, b, c, d, e, f, g, h) -> Bool #

(>=) :: (a, b, c, d, e, f, g, h) -> (a, b, c, d, e, f, g, h) -> Bool #

max :: (a, b, c, d, e, f, g, h) -> (a, b, c, d, e, f, g, h) -> (a, b, c, d, e, f, g, h) #

min :: (a, b, c, d, e, f, g, h) -> (a, b, c, d, e, f, g, h) -> (a, b, c, d, e, f, g, h) #

(Ord a, Ord b, Ord c, Ord d, Ord e, Ord f, Ord g, Ord h, Ord i) => Ord (a, b, c, d, e, f, g, h, i) 
Instance details

Defined in GHC.Classes

Methods

compare :: (a, b, c, d, e, f, g, h, i) -> (a, b, c, d, e, f, g, h, i) -> Ordering #

(<) :: (a, b, c, d, e, f, g, h, i) -> (a, b, c, d, e, f, g, h, i) -> Bool #

(<=) :: (a, b, c, d, e, f, g, h, i) -> (a, b, c, d, e, f, g, h, i) -> Bool #

(>) :: (a, b, c, d, e, f, g, h, i) -> (a, b, c, d, e, f, g, h, i) -> Bool #

(>=) :: (a, b, c, d, e, f, g, h, i) -> (a, b, c, d, e, f, g, h, i) -> Bool #

max :: (a, b, c, d, e, f, g, h, i) -> (a, b, c, d, e, f, g, h, i) -> (a, b, c, d, e, f, g, h, i) #

min :: (a, b, c, d, e, f, g, h, i) -> (a, b, c, d, e, f, g, h, i) -> (a, b, c, d, e, f, g, h, i) #

(Ord a, Ord b, Ord c, Ord d, Ord e, Ord f, Ord g, Ord h, Ord i, Ord j) => Ord (a, b, c, d, e, f, g, h, i, j) 
Instance details

Defined in GHC.Classes

Methods

compare :: (a, b, c, d, e, f, g, h, i, j) -> (a, b, c, d, e, f, g, h, i, j) -> Ordering #

(<) :: (a, b, c, d, e, f, g, h, i, j) -> (a, b, c, d, e, f, g, h, i, j) -> Bool #

(<=) :: (a, b, c, d, e, f, g, h, i, j) -> (a, b, c, d, e, f, g, h, i, j) -> Bool #

(>) :: (a, b, c, d, e, f, g, h, i, j) -> (a, b, c, d, e, f, g, h, i, j) -> Bool #

(>=) :: (a, b, c, d, e, f, g, h, i, j) -> (a, b, c, d, e, f, g, h, i, j) -> Bool #

max :: (a, b, c, d, e, f, g, h, i, j) -> (a, b, c, d, e, f, g, h, i, j) -> (a, b, c, d, e, f, g, h, i, j) #

min :: (a, b, c, d, e, f, g, h, i, j) -> (a, b, c, d, e, f, g, h, i, j) -> (a, b, c, d, e, f, g, h, i, j) #

(Ord a, Ord b, Ord c, Ord d, Ord e, Ord f, Ord g, Ord h, Ord i, Ord j, Ord k) => Ord (a, b, c, d, e, f, g, h, i, j, k) 
Instance details

Defined in GHC.Classes

Methods

compare :: (a, b, c, d, e, f, g, h, i, j, k) -> (a, b, c, d, e, f, g, h, i, j, k) -> Ordering #

(<) :: (a, b, c, d, e, f, g, h, i, j, k) -> (a, b, c, d, e, f, g, h, i, j, k) -> Bool #

(<=) :: (a, b, c, d, e, f, g, h, i, j, k) -> (a, b, c, d, e, f, g, h, i, j, k) -> Bool #

(>) :: (a, b, c, d, e, f, g, h, i, j, k) -> (a, b, c, d, e, f, g, h, i, j, k) -> Bool #

(>=) :: (a, b, c, d, e, f, g, h, i, j, k) -> (a, b, c, d, e, f, g, h, i, j, k) -> Bool #

max :: (a, b, c, d, e, f, g, h, i, j, k) -> (a, b, c, d, e, f, g, h, i, j, k) -> (a, b, c, d, e, f, g, h, i, j, k) #

min :: (a, b, c, d, e, f, g, h, i, j, k) -> (a, b, c, d, e, f, g, h, i, j, k) -> (a, b, c, d, e, f, g, h, i, j, k) #

(Ord a, Ord b, Ord c, Ord d, Ord e, Ord f, Ord g, Ord h, Ord i, Ord j, Ord k, Ord l) => Ord (a, b, c, d, e, f, g, h, i, j, k, l) 
Instance details

Defined in GHC.Classes

Methods

compare :: (a, b, c, d, e, f, g, h, i, j, k, l) -> (a, b, c, d, e, f, g, h, i, j, k, l) -> Ordering #

(<) :: (a, b, c, d, e, f, g, h, i, j, k, l) -> (a, b, c, d, e, f, g, h, i, j, k, l) -> Bool #

(<=) :: (a, b, c, d, e, f, g, h, i, j, k, l) -> (a, b, c, d, e, f, g, h, i, j, k, l) -> Bool #

(>) :: (a, b, c, d, e, f, g, h, i, j, k, l) -> (a, b, c, d, e, f, g, h, i, j, k, l) -> Bool #

(>=) :: (a, b, c, d, e, f, g, h, i, j, k, l) -> (a, b, c, d, e, f, g, h, i, j, k, l) -> Bool #

max :: (a, b, c, d, e, f, g, h, i, j, k, l) -> (a, b, c, d, e, f, g, h, i, j, k, l) -> (a, b, c, d, e, f, g, h, i, j, k, l) #

min :: (a, b, c, d, e, f, g, h, i, j, k, l) -> (a, b, c, d, e, f, g, h, i, j, k, l) -> (a, b, c, d, e, f, g, h, i, j, k, l) #

(Ord a, Ord b, Ord c, Ord d, Ord e, Ord f, Ord g, Ord h, Ord i, Ord j, Ord k, Ord l, Ord m) => Ord (a, b, c, d, e, f, g, h, i, j, k, l, m) 
Instance details

Defined in GHC.Classes

Methods

compare :: (a, b, c, d, e, f, g, h, i, j, k, l, m) -> (a, b, c, d, e, f, g, h, i, j, k, l, m) -> Ordering #

(<) :: (a, b, c, d, e, f, g, h, i, j, k, l, m) -> (a, b, c, d, e, f, g, h, i, j, k, l, m) -> Bool #

(<=) :: (a, b, c, d, e, f, g, h, i, j, k, l, m) -> (a, b, c, d, e, f, g, h, i, j, k, l, m) -> Bool #

(>) :: (a, b, c, d, e, f, g, h, i, j, k, l, m) -> (a, b, c, d, e, f, g, h, i, j, k, l, m) -> Bool #

(>=) :: (a, b, c, d, e, f, g, h, i, j, k, l, m) -> (a, b, c, d, e, f, g, h, i, j, k, l, m) -> Bool #

max :: (a, b, c, d, e, f, g, h, i, j, k, l, m) -> (a, b, c, d, e, f, g, h, i, j, k, l, m) -> (a, b, c, d, e, f, g, h, i, j, k, l, m) #

min :: (a, b, c, d, e, f, g, h, i, j, k, l, m) -> (a, b, c, d, e, f, g, h, i, j, k, l, m) -> (a, b, c, d, e, f, g, h, i, j, k, l, m) #

(Ord a, Ord b, Ord c, Ord d, Ord e, Ord f, Ord g, Ord h, Ord i, Ord j, Ord k, Ord l, Ord m, Ord n) => Ord (a, b, c, d, e, f, g, h, i, j, k, l, m, n) 
Instance details

Defined in GHC.Classes

Methods

compare :: (a, b, c, d, e, f, g, h, i, j, k, l, m, n) -> (a, b, c, d, e, f, g, h, i, j, k, l, m, n) -> Ordering #

(<) :: (a, b, c, d, e, f, g, h, i, j, k, l, m, n) -> (a, b, c, d, e, f, g, h, i, j, k, l, m, n) -> Bool #

(<=) :: (a, b, c, d, e, f, g, h, i, j, k, l, m, n) -> (a, b, c, d, e, f, g, h, i, j, k, l, m, n) -> Bool #

(>) :: (a, b, c, d, e, f, g, h, i, j, k, l, m, n) -> (a, b, c, d, e, f, g, h, i, j, k, l, m, n) -> Bool #

(>=) :: (a, b, c, d, e, f, g, h, i, j, k, l, m, n) -> (a, b, c, d, e, f, g, h, i, j, k, l, m, n) -> Bool #

max :: (a, b, c, d, e, f, g, h, i, j, k, l, m, n) -> (a, b, c, d, e, f, g, h, i, j, k, l, m, n) -> (a, b, c, d, e, f, g, h, i, j, k, l, m, n) #

min :: (a, b, c, d, e, f, g, h, i, j, k, l, m, n) -> (a, b, c, d, e, f, g, h, i, j, k, l, m, n) -> (a, b, c, d, e, f, g, h, i, j, k, l, m, n) #

(Ord a, Ord b, Ord c, Ord d, Ord e, Ord f, Ord g, Ord h, Ord i, Ord j, Ord k, Ord l, Ord m, Ord n, Ord o) => Ord (a, b, c, d, e, f, g, h, i, j, k, l, m, n, o) 
Instance details

Defined in GHC.Classes

Methods

compare :: (a, b, c, d, e, f, g, h, i, j, k, l, m, n, o) -> (a, b, c, d, e, f, g, h, i, j, k, l, m, n, o) -> Ordering #

(<) :: (a, b, c, d, e, f, g, h, i, j, k, l, m, n, o) -> (a, b, c, d, e, f, g, h, i, j, k, l, m, n, o) -> Bool #

(<=) :: (a, b, c, d, e, f, g, h, i, j, k, l, m, n, o) -> (a, b, c, d, e, f, g, h, i, j, k, l, m, n, o) -> Bool #

(>) :: (a, b, c, d, e, f, g, h, i, j, k, l, m, n, o) -> (a, b, c, d, e, f, g, h, i, j, k, l, m, n, o) -> Bool #

(>=) :: (a, b, c, d, e, f, g, h, i, j, k, l, m, n, o) -> (a, b, c, d, e, f, g, h, i, j, k, l, m, n, o) -> Bool #

max :: (a, b, c, d, e, f, g, h, i, j, k, l, m, n, o) -> (a, b, c, d, e, f, g, h, i, j, k, l, m, n, o) -> (a, b, c, d, e, f, g, h, i, j, k, l, m, n, o) #

min :: (a, b, c, d, e, f, g, h, i, j, k, l, m, n, o) -> (a, b, c, d, e, f, g, h, i, j, k, l, m, n, o) -> (a, b, c, d, e, f, g, h, i, j, k, l, m, n, o) #

class Read a where #

Parsing of Strings, producing values.

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

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

For example, given the declarations

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

the derived instance of Read in Haskell 2010 is equivalent to

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

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

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

          where app_prec = 10
                up_prec = 5

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

The derived instance in GHC is equivalent to

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

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

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

          where app_prec = 10
                up_prec = 5

        readListPrec = readListPrecDefault

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

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

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

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

Minimal complete definition

readsPrec | readPrec

Methods

readsPrec #

Arguments

:: Int

the operator precedence of the enclosing context (a number from 0 to 11). Function application has precedence 10.

-> ReadS a 

attempts to parse a value from the front of the string, returning a list of (parsed value, remaining string) pairs. If there is no successful parse, the returned list is empty.

Derived instances of Read and Show satisfy the following:

That is, readsPrec parses the string produced by showsPrec, and delivers the value that showsPrec started with.

readList :: ReadS [a] #

The method readList is provided to allow the programmer to give a specialised way of parsing lists of values. For example, this is used by the predefined Read instance of the Char type, where values of type String should be are expected to use double quotes, rather than square brackets.

Instances

Instances details
Read All

Since: base-2.1

Instance details

Defined in Data.Semigroup.Internal

Read Any

Since: base-2.1

Instance details

Defined in Data.Semigroup.Internal

Read Associativity

Since: base-4.6.0.0

Instance details

Defined in GHC.Generics

Read DecidedStrictness

Since: base-4.9.0.0

Instance details

Defined in GHC.Generics

Read Fixity

Since: base-4.6.0.0

Instance details

Defined in GHC.Generics

Read SourceStrictness

Since: base-4.9.0.0

Instance details

Defined in GHC.Generics

Read SourceUnpackedness

Since: base-4.9.0.0

Instance details

Defined in GHC.Generics

Read ExitCode 
Instance details

Defined in GHC.IO.Exception

Read Int16

Since: base-2.1

Instance details

Defined in GHC.Int

Read Int32

Since: base-2.1

Instance details

Defined in GHC.Int

Read Int64

Since: base-2.1

Instance details

Defined in GHC.Int

Read Int8

Since: base-2.1

Instance details

Defined in GHC.Int

Read SomeChar 
Instance details

Defined in GHC.TypeLits

Read SomeSymbol

Since: base-4.7.0.0

Instance details

Defined in GHC.TypeLits

Read SomeNat

Since: base-4.7.0.0

Instance details

Defined in GHC.TypeNats

Read GeneralCategory

Since: base-2.1

Instance details

Defined in GHC.Read

Read Word16

Since: base-2.1

Instance details

Defined in GHC.Read

Read Word32

Since: base-2.1

Instance details

Defined in GHC.Read

Read Word64

Since: base-2.1

Instance details

Defined in GHC.Read

Read Word8

Since: base-2.1

Instance details

Defined in GHC.Read

Read Lexeme

Since: base-2.1

Instance details

Defined in GHC.Read

Read IntSet 
Instance details

Defined in Data.IntSet.Internal

Read Ordering

Since: base-2.1

Instance details

Defined in GHC.Read

Read Integer

Since: base-2.1

Instance details

Defined in GHC.Read

Read Natural

Since: base-4.8.0.0

Instance details

Defined in GHC.Read

Read ()

Since: base-2.1

Instance details

Defined in GHC.Read

Methods

readsPrec :: Int -> ReadS () #

readList :: ReadS [()] #

readPrec :: ReadPrec () #

readListPrec :: ReadPrec [()] #

Read Bool

Since: base-2.1

Instance details

Defined in GHC.Read

Read Char

Since: base-2.1

Instance details

Defined in GHC.Read

Read Double

Since: base-2.1

Instance details

Defined in GHC.Read

Read Float

Since: base-2.1

Instance details

Defined in GHC.Read

Read Int

Since: base-2.1

Instance details

Defined in GHC.Read

Read Word

Since: base-4.5.0.0

Instance details

Defined in GHC.Read

Read a => Read (And a)

Since: base-4.16

Instance details

Defined in Data.Bits

Read a => Read (Iff a)

Since: base-4.16

Instance details

Defined in Data.Bits

Read a => Read (Ior a)

Since: base-4.16

Instance details

Defined in Data.Bits

Read a => Read (Xor a)

Since: base-4.16

Instance details

Defined in Data.Bits

Read a => Read (Identity a)

This instance would be equivalent to the derived instances of the Identity newtype if the runIdentity field were removed

Since: base-4.8.0.0

Instance details

Defined in Data.Functor.Identity

Read a => Read (First a)

Since: base-2.1

Instance details

Defined in Data.Monoid

Read a => Read (Last a)

Since: base-2.1

Instance details

Defined in Data.Monoid

Read a => Read (Down a)

This instance would be equivalent to the derived instances of the Down newtype if the getDown field were removed

Since: base-4.7.0.0

Instance details

Defined in Data.Ord

Read a => Read (Dual a)

Since: base-2.1

Instance details

Defined in Data.Semigroup.Internal

Read a => Read (Product a)

Since: base-2.1

Instance details

Defined in Data.Semigroup.Internal

Read a => Read (Sum a)

Since: base-2.1

Instance details

Defined in Data.Semigroup.Internal

Read p => Read (Par1 p)

Since: base-4.7.0.0

Instance details

Defined in GHC.Generics

(Integral a, Read a) => Read (Ratio a)

Since: base-2.1

Instance details

Defined in GHC.Read

Read e => Read (IntMap e) 
Instance details

Defined in Data.IntMap.Internal

Read a => Read (DList a) 
Instance details

Defined in Data.DList.Internal

Read a => Read (NonEmpty a)

Since: base-4.11.0.0

Instance details

Defined in GHC.Read

Read a => Read (Maybe a)

Since: base-2.1

Instance details

Defined in GHC.Read

Read a => Read (a)

Since: base-4.15

Instance details

Defined in GHC.Read

Methods

readsPrec :: Int -> ReadS (a) #

readList :: ReadS [(a)] #

readPrec :: ReadPrec (a) #

readListPrec :: ReadPrec [(a)] #

Read a => Read [a]

Since: base-2.1

Instance details

Defined in GHC.Read

Methods

readsPrec :: Int -> ReadS [a] #

readList :: ReadS [[a]] #

readPrec :: ReadPrec [a] #

readListPrec :: ReadPrec [[a]] #

(Read a, Read b) => Read (Either a b)

Since: base-3.0

Instance details

Defined in Data.Either

Read (Proxy t)

Since: base-4.7.0.0

Instance details

Defined in Data.Proxy

(Ix a, Read a, Read b) => Read (Array a b)

Since: base-2.1

Instance details

Defined in GHC.Read

Read (U1 p)

Since: base-4.9.0.0

Instance details

Defined in GHC.Generics

Read (V1 p)

Since: base-4.9.0.0

Instance details

Defined in GHC.Generics

(Read a, Read b) => Read (a, b)

Since: base-2.1

Instance details

Defined in GHC.Read

Methods

readsPrec :: Int -> ReadS (a, b) #

readList :: ReadS [(a, b)] #

readPrec :: ReadPrec (a, b) #

readListPrec :: ReadPrec [(a, b)] #

Read (f a) => Read (Ap f a)

Since: base-4.12.0.0

Instance details

Defined in Data.Monoid

Methods

readsPrec :: Int -> ReadS (Ap f a) #

readList :: ReadS [Ap f a] #

readPrec :: ReadPrec (Ap f a) #

readListPrec :: ReadPrec [Ap f a] #

Read (f a) => Read (Alt f a)

Since: base-4.8.0.0

Instance details

Defined in Data.Semigroup.Internal

Methods

readsPrec :: Int -> ReadS (Alt f a) #

readList :: ReadS [Alt f a] #

readPrec :: ReadPrec (Alt f a) #

readListPrec :: ReadPrec [Alt f a] #

a ~ b => Read (a :~: b)

Since: base-4.7.0.0

Instance details

Defined in Data.Type.Equality

Methods

readsPrec :: Int -> ReadS (a :~: b) #

readList :: ReadS [a :~: b] #

readPrec :: ReadPrec (a :~: b) #

readListPrec :: ReadPrec [a :~: b] #

Read (f p) => Read (Rec1 f p)

Since: base-4.7.0.0

Instance details

Defined in GHC.Generics

Methods

readsPrec :: Int -> ReadS (Rec1 f p) #

readList :: ReadS [Rec1 f p] #

readPrec :: ReadPrec (Rec1 f p) #

readListPrec :: ReadPrec [Rec1 f p] #

(Read e, Read1 m, Read a) => Read (ErrorT e m a) 
Instance details

Defined in Control.Monad.Trans.Error

Methods

readsPrec :: Int -> ReadS (ErrorT e m a) #

readList :: ReadS [ErrorT e m a] #

readPrec :: ReadPrec (ErrorT e m a) #

readListPrec :: ReadPrec [ErrorT e m a] #

(Read w, Read1 m, Read a) => Read (WriterT w m a) 
Instance details

Defined in Control.Monad.Trans.Writer.Lazy

Methods

readsPrec :: Int -> ReadS (WriterT w m a) #

readList :: ReadS [WriterT w m a] #

readPrec :: ReadPrec (WriterT w m a) #

readListPrec :: ReadPrec [WriterT w m a] #

(Read a, Read b, Read c) => Read (a, b, c)

Since: base-2.1

Instance details

Defined in GHC.Read

Methods

readsPrec :: Int -> ReadS (a, b, c) #

readList :: ReadS [(a, b, c)] #

readPrec :: ReadPrec (a, b, c) #

readListPrec :: ReadPrec [(a, b, c)] #

a ~~ b => Read (a :~~: b)

Since: base-4.10.0.0

Instance details

Defined in Data.Type.Equality

Methods

readsPrec :: Int -> ReadS (a :~~: b) #

readList :: ReadS [a :~~: b] #

readPrec :: ReadPrec (a :~~: b) #

readListPrec :: ReadPrec [a :~~: b] #

(Read (f p), Read (g p)) => Read ((f :*: g) p)

Since: base-4.7.0.0

Instance details

Defined in GHC.Generics

Methods

readsPrec :: Int -> ReadS ((f :*: g) p) #

readList :: ReadS [(f :*: g) p] #

readPrec :: ReadPrec ((f :*: g) p) #

readListPrec :: ReadPrec [(f :*: g) p] #

(Read (f p), Read (g p)) => Read ((f :+: g) p)

Since: base-4.7.0.0

Instance details

Defined in GHC.Generics

Methods

readsPrec :: Int -> ReadS ((f :+: g) p) #

readList :: ReadS [(f :+: g) p] #

readPrec :: ReadPrec ((f :+: g) p) #

readListPrec :: ReadPrec [(f :+: g) p] #

Read c => Read (K1 i c p)

Since: base-4.7.0.0

Instance details

Defined in GHC.Generics

Methods

readsPrec :: Int -> ReadS (K1 i c p) #

readList :: ReadS [K1 i c p] #

readPrec :: ReadPrec (K1 i c p) #

readListPrec :: ReadPrec [K1 i c p] #

(Read a, Read b, Read c, Read d) => Read (a, b, c, d)

Since: base-2.1

Instance details

Defined in GHC.Read

Methods

readsPrec :: Int -> ReadS (a, b, c, d) #

readList :: ReadS [(a, b, c, d)] #

readPrec :: ReadPrec (a, b, c, d) #

readListPrec :: ReadPrec [(a, b, c, d)] #

Read (f (g p)) => Read ((f :.: g) p)

Since: base-4.7.0.0

Instance details

Defined in GHC.Generics

Methods

readsPrec :: Int -> ReadS ((f :.: g) p) #

readList :: ReadS [(f :.: g) p] #

readPrec :: ReadPrec ((f :.: g) p) #

readListPrec :: ReadPrec [(f :.: g) p] #

Read (f p) => Read (M1 i c f p)

Since: base-4.7.0.0

Instance details

Defined in GHC.Generics

Methods

readsPrec :: Int -> ReadS (M1 i c f p) #

readList :: ReadS [M1 i c f p] #

readPrec :: ReadPrec (M1 i c f p) #

readListPrec :: ReadPrec [M1 i c f p] #

(Read a, Read b, Read c, Read d, Read e) => Read (a, b, c, d, e)

Since: base-2.1

Instance details

Defined in GHC.Read

Methods

readsPrec :: Int -> ReadS (a, b, c, d, e) #

readList :: ReadS [(a, b, c, d, e)] #

readPrec :: ReadPrec (a, b, c, d, e) #

readListPrec :: ReadPrec [(a, b, c, d, e)] #

(Read a, Read b, Read c, Read d, Read e, Read f) => Read (a, b, c, d, e, f)

Since: base-2.1

Instance details

Defined in GHC.Read

Methods

readsPrec :: Int -> ReadS (a, b, c, d, e, f) #

readList :: ReadS [(a, b, c, d, e, f)] #

readPrec :: ReadPrec (a, b, c, d, e, f) #

readListPrec :: ReadPrec [(a, b, c, d, e, f)] #

(Read a, Read b, Read c, Read d, Read e, Read f, Read g) => Read (a, b, c, d, e, f, g)

Since: base-2.1

Instance details

Defined in GHC.Read

Methods

readsPrec :: Int -> ReadS (a, b, c, d, e, f, g) #

readList :: ReadS [(a, b, c, d, e, f, g)] #

readPrec :: ReadPrec (a, b, c, d, e, f, g) #

readListPrec :: ReadPrec [(a, b, c, d, e, f, g)] #

(Read a, Read b, Read c, Read d, Read e, Read f, Read g, Read h) => Read (a, b, c, d, e, f, g, h)

Since: base-2.1

Instance details

Defined in GHC.Read

Methods

readsPrec :: Int -> ReadS (a, b, c, d, e, f, g, h) #

readList :: ReadS [(a, b, c, d, e, f, g, h)] #

readPrec :: ReadPrec (a, b, c, d, e, f, g, h) #

readListPrec :: ReadPrec [(a, b, c, d, e, f, g, h)] #

(Read a, Read b, Read c, Read d, Read e, Read f, Read g, Read h, Read i) => Read (a, b, c, d, e, f, g, h, i)

Since: base-2.1

Instance details

Defined in GHC.Read

Methods

readsPrec :: Int -> ReadS (a, b, c, d, e, f, g, h, i) #

readList :: ReadS [(a, b, c, d, e, f, g, h, i)] #

readPrec :: ReadPrec (a, b, c, d, e, f, g, h, i) #

readListPrec :: ReadPrec [(a, b, c, d, e, f, g, h, i)] #

(Read a, Read b, Read c, Read d, Read e, Read f, Read g, Read h, Read i, Read j) => Read (a, b, c, d, e, f, g, h, i, j)

Since: base-2.1

Instance details

Defined in GHC.Read

Methods

readsPrec :: Int -> ReadS (a, b, c, d, e, f, g, h, i, j) #

readList :: ReadS [(a, b, c, d, e, f, g, h, i, j)] #

readPrec :: ReadPrec (a, b, c, d, e, f, g, h, i, j) #

readListPrec :: ReadPrec [(a, b, c, d, e, f, g, h, i, j)] #

(Read a, Read b, Read c, Read d, Read e, Read f, Read g, Read h, Read i, Read j, Read k) => Read (a, b, c, d, e, f, g, h, i, j, k)

Since: base-2.1

Instance details

Defined in GHC.Read

Methods

readsPrec :: Int -> ReadS (a, b, c, d, e, f, g, h, i, j, k) #

readList :: ReadS [(a, b, c, d, e, f, g, h, i, j, k)] #

readPrec :: ReadPrec (a, b, c, d, e, f, g, h, i, j, k) #

readListPrec :: ReadPrec [(a, b, c, d, e, f, g, h, i, j, k)] #

(Read a, Read b, Read c, Read d, Read e, Read f, Read g, Read h, Read i, Read j, Read k, Read l) => Read (a, b, c, d, e, f, g, h, i, j, k, l)

Since: base-2.1

Instance details

Defined in GHC.Read

Methods

readsPrec :: Int -> ReadS (a, b, c, d, e, f, g, h, i, j, k, l) #

readList :: ReadS [(a, b, c, d, e, f, g, h, i, j, k, l)] #

readPrec :: ReadPrec (a, b, c, d, e, f, g, h, i, j, k, l) #

readListPrec :: ReadPrec [(a, b, c, d, e, f, g, h, i, j, k, l)] #

(Read a, Read b, Read c, Read d, Read e, Read f, Read g, Read h, Read i, Read j, Read k, Read l, Read m) => Read (a, b, c, d, e, f, g, h, i, j, k, l, m)

Since: base-2.1

Instance details

Defined in GHC.Read

Methods

readsPrec :: Int -> ReadS (a, b, c, d, e, f, g, h, i, j, k, l, m) #

readList :: ReadS [(a, b, c, d, e, f, g, h, i, j, k, l, m)] #

readPrec :: ReadPrec (a, b, c, d, e, f, g, h, i, j, k, l, m) #

readListPrec :: ReadPrec [(a, b, c, d, e, f, g, h, i, j, k, l, m)] #

(Read a, Read b, Read c, Read d, Read e, Read f, Read g, Read h, Read i, Read j, Read k, Read l, Read m, Read n) => Read (a, b, c, d, e, f, g, h, i, j, k, l, m, n)

Since: base-2.1

Instance details

Defined in GHC.Read

Methods

readsPrec :: Int -> ReadS (a, b, c, d, e, f, g, h, i, j, k, l, m, n) #

readList :: ReadS [(a, b, c, d, e, f, g, h, i, j, k, l, m, n)] #

readPrec :: ReadPrec (a, b, c, d, e, f, g, h, i, j, k, l, m, n) #

readListPrec :: ReadPrec [(a, b, c, d, e, f, g, h, i, j, k, l, m, n)] #

(Read a, Read b, Read c, Read d, Read e, Read f, Read g, Read h, Read i, Read j, Read k, Read l, Read m, Read n, Read o) => Read (a, b, c, d, e, f, g, h, i, j, k, l, m, n, o)

Since: base-2.1

Instance details

Defined in GHC.Read

Methods

readsPrec :: Int -> ReadS (a, b, c, d, e, f, g, h, i, j, k, l, m, n, o) #

readList :: ReadS [(a, b, c, d, e, f, g, h, i, j, k, l, m, n, o)] #

readPrec :: ReadPrec (a, b, c, d, e, f, g, h, i, j, k, l, m, n, o) #

readListPrec :: ReadPrec [(a, b, c, d, e, f, g, h, i, j, k, l, m, n, o)] #

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

Methods

toRational :: a -> Rational #

the rational equivalent of its real argument with full precision

Instances

Instances details
Real Int16

Since: base-2.1

Instance details

Defined in GHC.Int

Methods

toRational :: Int16 -> Rational #

Real Int32

Since: base-2.1

Instance details

Defined in GHC.Int

Methods

toRational :: Int32 -> Rational #

Real Int64

Since: base-2.1

Instance details

Defined in GHC.Int

Methods

toRational :: Int64 -> Rational #

Real Int8

Since: base-2.1

Instance details

Defined in GHC.Int

Methods

toRational :: Int8 -> Rational #

Real Word16

Since: base-2.1

Instance details

Defined in GHC.Word

Real Word32

Since: base-2.1

Instance details

Defined in GHC.Word

Real Word64

Since: base-2.1

Instance details

Defined in GHC.Word

Real Word8

Since: base-2.1

Instance details

Defined in GHC.Word

Methods

toRational :: Word8 -> Rational #

Real Integer

Since: base-2.0.1

Instance details

Defined in GHC.Real

Real Natural

Since: base-4.8.0.0

Instance details

Defined in GHC.Real

Real Int

Since: base-2.0.1

Instance details

Defined in GHC.Real

Methods

toRational :: Int -> Rational #

Real Word

Since: base-2.1

Instance details

Defined in GHC.Real

Methods

toRational :: Word -> Rational #

Real a => Real (Identity a)

Since: base-4.9.0.0

Instance details

Defined in Data.Functor.Identity

Methods

toRational :: Identity a -> Rational #

Real a => Real (Down a)

Since: base-4.14.0.0

Instance details

Defined in Data.Ord

Methods

toRational :: Down a -> Rational #

Integral a => Real (Ratio a)

Since: base-2.0.1

Instance details

Defined in GHC.Real

Methods

toRational :: Ratio a -> Rational #

class (RealFrac a, Floating a) => RealFloat a where #

Efficient, machine-independent access to the components of a floating-point number.

Methods

floatRadix :: a -> Integer #

a constant function, returning the radix of the representation (often 2)

floatDigits :: a -> Int #

a constant function, returning the number of digits of floatRadix in the significand

floatRange :: a -> (Int, Int) #

a constant function, returning the lowest and highest values the exponent may assume

decodeFloat :: a -> (Integer, Int) #

The function decodeFloat applied to a real floating-point number returns the significand expressed as an Integer and an appropriately scaled exponent (an Int). If decodeFloat x yields (m,n), then x is equal in value to m*b^^n, where b is the floating-point radix, and furthermore, either m and n are both zero or else b^(d-1) <= abs m < b^d, where d is the value of floatDigits x. In particular, decodeFloat 0 = (0,0). If the type contains a negative zero, also decodeFloat (-0.0) = (0,0). The result of decodeFloat x is unspecified if either of isNaN x or isInfinite x is True.

encodeFloat :: Integer -> Int -> a #

encodeFloat performs the inverse of decodeFloat in the sense that for finite x with the exception of -0.0, uncurry encodeFloat (decodeFloat x) = x. encodeFloat m n is one of the two closest representable floating-point numbers to m*b^^n (or ±Infinity if overflow occurs); usually the closer, but if m contains too many bits, the result may be rounded in the wrong direction.

exponent :: a -> Int #

exponent corresponds to the second component of decodeFloat. exponent 0 = 0 and for finite nonzero x, exponent x = snd (decodeFloat x) + floatDigits x. If x is a finite floating-point number, it is equal in value to significand x * b ^^ exponent x, where b is the floating-point radix. The behaviour is unspecified on infinite or NaN values.

significand :: a -> a #

The first component of decodeFloat, scaled to lie in the open interval (-1,1), either 0.0 or of absolute value >= 1/b, where b is the floating-point radix. The behaviour is unspecified on infinite or NaN values.

scaleFloat :: Int -> a -> a #

multiplies a floating-point number by an integer power of the radix

isNaN :: a -> Bool #

True if the argument is an IEEE "not-a-number" (NaN) value

isInfinite :: a -> Bool #

True if the argument is an IEEE infinity or negative infinity

isDenormalized :: a -> Bool #

True if the argument is too small to be represented in normalized format

isNegativeZero :: a -> Bool #

True if the argument is an IEEE negative zero

isIEEE :: a -> Bool #

True if the argument is an IEEE floating point number

atan2 :: a -> a -> a #

a version of arctangent taking two real floating-point arguments. For real floating x and y, atan2 y x computes the angle (from the positive x-axis) of the vector from the origin to the point (x,y). atan2 y x returns a value in the range [-pi, pi]. It follows the Common Lisp semantics for the origin when signed zeroes are supported. atan2 y 1, with y in a type that is RealFloat, should return the same value as atan y. A default definition of atan2 is provided, but implementors can provide a more accurate implementation.

Instances

Instances details
RealFloat Double

Since: base-2.1

Instance details

Defined in GHC.Float

RealFloat Float

Since: base-2.1

Instance details

Defined in GHC.Float

RealFloat a => RealFloat (Identity a)

Since: base-4.9.0.0

Instance details

Defined in Data.Functor.Identity

RealFloat a => RealFloat (Down a)

Since: base-4.14.0.0

Instance details

Defined in Data.Ord

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

Extracting components of fractions.

Minimal complete definition

properFraction

Methods

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

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

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

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

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

truncate x returns the integer nearest x between zero and x

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

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

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

ceiling x returns the least integer not less than x

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

floor x returns the greatest integer not greater than x

Instances

Instances details
RealFrac a => RealFrac (Identity a)

Since: base-4.9.0.0

Instance details

Defined in Data.Functor.Identity

Methods

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

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

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

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

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

RealFrac a => RealFrac (Down a)

Since: base-4.14.0.0

Instance details

Defined in Data.Ord

Methods

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

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

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

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

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

Integral a => RealFrac (Ratio a)

Since: base-2.0.1

Instance details

Defined in GHC.Real

Methods

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

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

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

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

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

class Show a where #

Conversion of values to readable Strings.

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

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

For example, given the declarations

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

the derived instance of Show is equivalent to

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

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

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

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

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

Minimal complete definition

showsPrec | show

Methods

showsPrec #

Arguments

:: Int

the operator precedence of the enclosing context (a number from 0 to 11). Function application has precedence 10.

-> a

the value to be converted to a String

-> ShowS 

Convert a value to a readable String.

showsPrec should satisfy the law

showsPrec d x r ++ s  ==  showsPrec d x (r ++ s)

Derived instances of Read and Show satisfy the following:

That is, readsPrec parses the string produced by showsPrec, and delivers the value that showsPrec started with.

show :: a -> String #

A specialised variant of showsPrec, using precedence context zero, and returning an ordinary String.

showList :: [a] -> ShowS #

The method showList is provided to allow the programmer to give a specialised way of showing lists of values. For example, this is used by the predefined Show instance of the Char type, where values of type String should be shown in double quotes, rather than between square brackets.

Instances

Instances details
Show All

Since: base-2.1

Instance details

Defined in Data.Semigroup.Internal

Methods

showsPrec :: Int -> All -> ShowS #

show :: All -> String #

showList :: [All] -> ShowS #

Show Any

Since: base-2.1

Instance details

Defined in Data.Semigroup.Internal

Methods

showsPrec :: Int -> Any -> ShowS #

show :: Any -> String #

showList :: [Any] -> ShowS #

Show SomeTypeRep

Since: base-4.10.0.0

Instance details

Defined in Data.Typeable.Internal

Show ErrorCall

Since: base-4.0.0.0

Instance details

Defined in GHC.Exception

Show ArithException

Since: base-4.0.0.0

Instance details

Defined in GHC.Exception.Type

Show SomeException

Since: base-3.0

Instance details

Defined in GHC.Exception.Type

Show Associativity

Since: base-4.6.0.0

Instance details

Defined in GHC.Generics

Show DecidedStrictness

Since: base-4.9.0.0

Instance details

Defined in GHC.Generics

Show Fixity

Since: base-4.6.0.0

Instance details

Defined in GHC.Generics

Show SourceStrictness

Since: base-4.9.0.0

Instance details

Defined in GHC.Generics

Show SourceUnpackedness

Since: base-4.9.0.0

Instance details

Defined in GHC.Generics

Show MaskingState

Since: base-4.3.0.0

Instance details

Defined in GHC.IO

Show AllocationLimitExceeded

Since: base-4.7.1.0

Instance details

Defined in GHC.IO.Exception

Show ArrayException

Since: base-4.1.0.0

Instance details

Defined in GHC.IO.Exception

Show AssertionFailed

Since: base-4.1.0.0

Instance details

Defined in GHC.IO.Exception

Show AsyncException

Since: base-4.1.0.0

Instance details

Defined in GHC.IO.Exception

Show BlockedIndefinitelyOnMVar

Since: base-4.1.0.0

Instance details

Defined in GHC.IO.Exception

Show BlockedIndefinitelyOnSTM

Since: base-4.1.0.0

Instance details

Defined in GHC.IO.Exception

Show CompactionFailed

Since: base-4.10.0.0

Instance details

Defined in GHC.IO.Exception

Show Deadlock

Since: base-4.1.0.0

Instance details

Defined in GHC.IO.Exception

Show ExitCode 
Instance details

Defined in GHC.IO.Exception

Show FixIOException

Since: base-4.11.0.0

Instance details

Defined in GHC.IO.Exception

Show IOErrorType

Since: base-4.1.0.0

Instance details

Defined in GHC.IO.Exception

Show IOException

Since: base-4.1.0.0

Instance details

Defined in GHC.IO.Exception

Show SomeAsyncException

Since: base-4.7.0.0

Instance details

Defined in GHC.IO.Exception

Show Int16

Since: base-2.1

Instance details

Defined in GHC.Int

Methods

showsPrec :: Int -> Int16 -> ShowS #

show :: Int16 -> String #

showList :: [Int16] -> ShowS #

Show Int32

Since: base-2.1

Instance details

Defined in GHC.Int

Methods

showsPrec :: Int -> Int32 -> ShowS #

show :: Int32 -> String #

showList :: [Int32] -> ShowS #

Show Int64

Since: base-2.1

Instance details

Defined in GHC.Int

Methods

showsPrec :: Int -> Int64 -> ShowS #

show :: Int64 -> String #

showList :: [Int64] -> ShowS #

Show Int8

Since: base-2.1

Instance details

Defined in GHC.Int

Methods

showsPrec :: Int -> Int8 -> ShowS #

show :: Int8 -> String #

showList :: [Int8] -> ShowS #

Show FractionalExponentBase 
Instance details

Defined in GHC.Real

Show CallStack

Since: base-4.9.0.0

Instance details

Defined in GHC.Show

Show SrcLoc

Since: base-4.9.0.0

Instance details

Defined in GHC.Show

Show SomeChar 
Instance details

Defined in GHC.TypeLits

Show SomeSymbol

Since: base-4.7.0.0

Instance details

Defined in GHC.TypeLits

Show SomeNat

Since: base-4.7.0.0

Instance details

Defined in GHC.TypeNats

Show Word16

Since: base-2.1

Instance details

Defined in GHC.Word

Show Word32

Since: base-2.1

Instance details

Defined in GHC.Word

Show Word64

Since: base-2.1

Instance details

Defined in GHC.Word

Show Word8

Since: base-2.1

Instance details

Defined in GHC.Word

Methods

showsPrec :: Int -> Word8 -> ShowS #

show :: Word8 -> String #

showList :: [Word8] -> ShowS #

Show IntSet 
Instance details

Defined in Data.IntSet.Internal

Show KindRep 
Instance details

Defined in GHC.Show

Show Module

Since: base-4.9.0.0

Instance details

Defined in GHC.Show

Show Ordering

Since: base-2.1

Instance details

Defined in GHC.Show

Show TrName

Since: base-4.9.0.0

Instance details

Defined in GHC.Show

Show TyCon

Since: base-2.1

Instance details

Defined in GHC.Show

Methods

showsPrec :: Int -> TyCon -> ShowS #

show :: TyCon -> String #

showList :: [TyCon] -> ShowS #

Show TypeLitSort

Since: base-4.11.0.0

Instance details

Defined in GHC.Show

Show Mode 
Instance details

Defined in Text.PrettyPrint.Annotated.HughesPJ

Methods

showsPrec :: Int -> Mode -> ShowS #

show :: Mode -> String #

showList :: [Mode] -> ShowS #

Show Style 
Instance details

Defined in Text.PrettyPrint.Annotated.HughesPJ

Methods

showsPrec :: Int -> Style -> ShowS #

show :: Style -> String #

showList :: [Style] -> ShowS #

Show TextDetails 
Instance details

Defined in Text.PrettyPrint.Annotated.HughesPJ

Show Doc 
Instance details

Defined in Text.PrettyPrint.HughesPJ

Methods

showsPrec :: Int -> Doc -> ShowS #

show :: Doc -> String #

showList :: [Doc] -> ShowS #

Show Integer

Since: base-2.1

Instance details

Defined in GHC.Show

Show Natural

Since: base-4.8.0.0

Instance details

Defined in GHC.Show

Show ()

Since: base-2.1

Instance details

Defined in GHC.Show

Methods

showsPrec :: Int -> () -> ShowS #

show :: () -> String #

showList :: [()] -> ShowS #

Show Bool

Since: base-2.1

Instance details

Defined in GHC.Show

Methods

showsPrec :: Int -> Bool -> ShowS #

show :: Bool -> String #

showList :: [Bool] -> ShowS #

Show Char

Since: base-2.1

Instance details

Defined in GHC.Show

Methods

showsPrec :: Int -> Char -> ShowS #

show :: Char -> String #

showList :: [Char] -> ShowS #

Show Int

Since: base-2.1

Instance details

Defined in GHC.Show

Methods

showsPrec :: Int -> Int -> ShowS #

show :: Int -> String #

showList :: [Int] -> ShowS #

Show Levity

Since: base-4.15.0.0

Instance details

Defined in GHC.Show

Show RuntimeRep

Since: base-4.11.0.0

Instance details

Defined in GHC.Show

Show VecCount

Since: base-4.11.0.0

Instance details

Defined in GHC.Show

Show VecElem

Since: base-4.11.0.0

Instance details

Defined in GHC.Show

Show Word

Since: base-2.1

Instance details

Defined in GHC.Show

Methods

showsPrec :: Int -> Word -> ShowS #

show :: Word -> String #

showList :: [Word] -> ShowS #

Show a => Show (And a)

Since: base-4.16

Instance details

Defined in Data.Bits

Methods

showsPrec :: Int -> And a -> ShowS #

show :: And a -> String #

showList :: [And a] -> ShowS #

Show a => Show (Iff a)

Since: base-4.16

Instance details

Defined in Data.Bits

Methods

showsPrec :: Int -> Iff a -> ShowS #

show :: Iff a -> String #

showList :: [Iff a] -> ShowS #

Show a => Show (Ior a)

Since: base-4.16

Instance details

Defined in Data.Bits

Methods

showsPrec :: Int -> Ior a -> ShowS #

show :: Ior a -> String #

showList :: [Ior a] -> ShowS #

Show a => Show (Xor a)

Since: base-4.16

Instance details

Defined in Data.Bits

Methods

showsPrec :: Int -> Xor a -> ShowS #

show :: Xor a -> String #

showList :: [Xor a] -> ShowS #

Show a => Show (Identity a)

This instance would be equivalent to the derived instances of the Identity newtype if the runIdentity field were removed

Since: base-4.8.0.0

Instance details

Defined in Data.Functor.Identity

Methods

showsPrec :: Int -> Identity a -> ShowS #

show :: Identity a -> String #

showList :: [Identity a] -> ShowS #

Show a => Show (First a)

Since: base-2.1

Instance details

Defined in Data.Monoid

Methods

showsPrec :: Int -> First a -> ShowS #

show :: First a -> String #

showList :: [First a] -> ShowS #

Show a => Show (Last a)

Since: base-2.1

Instance details

Defined in Data.Monoid

Methods

showsPrec :: Int -> Last a -> ShowS #

show :: Last a -> String #

showList :: [Last a] -> ShowS #

Show a => Show (Down a)

This instance would be equivalent to the derived instances of the Down newtype if the getDown field were removed

Since: base-4.7.0.0

Instance details

Defined in Data.Ord

Methods

showsPrec :: Int -> Down a -> ShowS #

show :: Down a -> String #

showList :: [Down a] -> ShowS #

Show a => Show (Dual a)

Since: base-2.1

Instance details

Defined in Data.Semigroup.Internal

Methods

showsPrec :: Int -> Dual a -> ShowS #

show :: Dual a -> String #

showList :: [Dual a] -> ShowS #

Show a => Show (Product a)

Since: base-2.1

Instance details

Defined in Data.Semigroup.Internal

Methods

showsPrec :: Int -> Product a -> ShowS #

show :: Product a -> String #

showList :: [Product a] -> ShowS #

Show a => Show (Sum a)

Since: base-2.1

Instance details

Defined in Data.Semigroup.Internal

Methods

showsPrec :: Int -> Sum a -> ShowS #

show :: Sum a -> String #

showList :: [Sum a] -> ShowS #

Show p => Show (Par1 p)

Since: base-4.7.0.0

Instance details

Defined in GHC.Generics

Methods

showsPrec :: Int -> Par1 p -> ShowS #

show :: Par1 p -> String #

showList :: [Par1 p] -> ShowS #

Show (FunPtr a)

Since: base-2.1

Instance details

Defined in GHC.Ptr

Methods

showsPrec :: Int -> FunPtr a -> ShowS #

show :: FunPtr a -> String #

showList :: [FunPtr a] -> ShowS #

Show (Ptr a)

Since: base-2.1

Instance details

Defined in GHC.Ptr

Methods

showsPrec :: Int -> Ptr a -> ShowS #

show :: Ptr a -> String #

showList :: [Ptr a] -> ShowS #

Show a => Show (Ratio a)

Since: base-2.0.1

Instance details

Defined in GHC.Real

Methods

showsPrec :: Int -> Ratio a -> ShowS #

show :: Ratio a -> String #

showList :: [Ratio a] -> ShowS #

Show a => Show (IntMap a) 
Instance details

Defined in Data.IntMap.Internal

Methods

showsPrec :: Int -> IntMap a -> ShowS #

show :: IntMap a -> String #

showList :: [IntMap a] -> ShowS #

Show (Stream a) Source #

Dummy instance in order to make Stream an instance of Num.

Instance details

Defined in Copilot.Language.Stream

Methods

showsPrec :: Int -> Stream a -> ShowS #

show :: Stream a -> String #

showList :: [Stream a] -> ShowS #

Show a => Show (DList a) 
Instance details

Defined in Data.DList.Internal

Methods

showsPrec :: Int -> DList a -> ShowS #

show :: DList a -> String #

showList :: [DList a] -> ShowS #

Show a => Show (AnnotDetails a) 
Instance details

Defined in Text.PrettyPrint.Annotated.HughesPJ

Show (Doc a) 
Instance details

Defined in Text.PrettyPrint.Annotated.HughesPJ

Methods

showsPrec :: Int -> Doc a -> ShowS #

show :: Doc a -> String #

showList :: [Doc a] -> ShowS #

Show a => Show (Span a) 
Instance details

Defined in Text.PrettyPrint.Annotated.HughesPJ

Methods

showsPrec :: Int -> Span a -> ShowS #

show :: Span a -> String #

showList :: [Span a] -> ShowS #

Show a => Show (NonEmpty a)

Since: base-4.11.0.0

Instance details

Defined in GHC.Show

Methods

showsPrec :: Int -> NonEmpty a -> ShowS #

show :: NonEmpty a -> String #

showList :: [NonEmpty a] -> ShowS #

Show a => Show (Maybe a)

Since: base-2.1

Instance details

Defined in GHC.Show

Methods

showsPrec :: Int -> Maybe a -> ShowS #

show :: Maybe a -> String #

showList :: [Maybe a] -> ShowS #

Show a => Show (a)

Since: base-4.15

Instance details

Defined in GHC.Show

Methods

showsPrec :: Int -> (a) -> ShowS #

show :: (a) -> String #

showList :: [(a)] -> ShowS #

Show a => Show [a]

Since: base-2.1

Instance details

Defined in GHC.Show

Methods

showsPrec :: Int -> [a] -> ShowS #

show :: [a] -> String #

showList :: [[a]] -> ShowS #

(Show a, Show b) => Show (Either a b)

Since: base-3.0

Instance details

Defined in Data.Either

Methods

showsPrec :: Int -> Either a b -> ShowS #

show :: Either a b -> String #

showList :: [Either a b] -> ShowS #

Show (Proxy s)

Since: base-4.7.0.0

Instance details

Defined in Data.Proxy

Methods

showsPrec :: Int -> Proxy s -> ShowS #

show :: Proxy s -> String #

showList :: [Proxy s] -> ShowS #

Show (TypeRep a) 
Instance details

Defined in Data.Typeable.Internal

Methods

showsPrec :: Int -> TypeRep a -> ShowS #

show :: TypeRep a -> String #

showList :: [TypeRep a] -> ShowS #

(Ix a, Show a, Show b) => Show (Array a b)

Since: base-2.1

Instance details

Defined in GHC.Arr

Methods

showsPrec :: Int -> Array a b -> ShowS #

show :: Array a b -> String #

showList :: [Array a b] -> ShowS #

Show (U1 p)

Since: base-4.9.0.0

Instance details

Defined in GHC.Generics

Methods

showsPrec :: Int -> U1 p -> ShowS #

show :: U1 p -> String #

showList :: [U1 p] -> ShowS #

Show (V1 p)

Since: base-4.9.0.0

Instance details

Defined in GHC.Generics

Methods

showsPrec :: Int -> V1 p -> ShowS #

show :: V1 p -> String #

showList :: [V1 p] -> ShowS #

(KnownSymbol s, Show t) => Show (Field s t) 
Instance details

Defined in Copilot.Core.Type

Methods

showsPrec :: Int -> Field s t -> ShowS #

show :: Field s t -> String #

showList :: [Field s t] -> ShowS #

Show t => Show (Array n t) 
Instance details

Defined in Copilot.Core.Type.Array

Methods

showsPrec :: Int -> Array n t -> ShowS #

show :: Array n t -> String #

showList :: [Array n t] -> ShowS #

(Show a, Show b) => Show (a, b)

Since: base-2.1

Instance details

Defined in GHC.Show

Methods

showsPrec :: Int -> (a, b) -> ShowS #

show :: (a, b) -> String #

showList :: [(a, b)] -> ShowS #

Show (f a) => Show (Ap f a)

Since: base-4.12.0.0

Instance details

Defined in Data.Monoid

Methods

showsPrec :: Int -> Ap f a -> ShowS #

show :: Ap f a -> String #

showList :: [Ap f a] -> ShowS #

Show (f a) => Show (Alt f a)

Since: base-4.8.0.0

Instance details

Defined in Data.Semigroup.Internal

Methods

showsPrec :: Int -> Alt f a -> ShowS #

show :: Alt f a -> String #

showList :: [Alt f a] -> ShowS #

Show (a :~: b)

Since: base-4.7.0.0

Instance details

Defined in Data.Type.Equality

Methods

showsPrec :: Int -> (a :~: b) -> ShowS #

show :: (a :~: b) -> String #

showList :: [a :~: b] -> ShowS #

Show (f p) => Show (Rec1 f p)

Since: base-4.7.0.0

Instance details

Defined in GHC.Generics

Methods

showsPrec :: Int -> Rec1 f p -> ShowS #

show :: Rec1 f p -> String #

showList :: [Rec1 f p] -> ShowS #

Show (URec Char p)

Since: base-4.9.0.0

Instance details

Defined in GHC.Generics

Methods

showsPrec :: Int -> URec Char p -> ShowS #

show :: URec Char p -> String #

showList :: [URec Char p] -> ShowS #

Show (URec Double p)

Since: base-4.9.0.0

Instance details

Defined in GHC.Generics

Methods

showsPrec :: Int -> URec Double p -> ShowS #

show :: URec Double p -> String #

showList :: [URec Double p] -> ShowS #

Show (URec Float p) 
Instance details

Defined in GHC.Generics

Methods

showsPrec :: Int -> URec Float p -> ShowS #

show :: URec Float p -> String #

showList :: [URec Float p] -> ShowS #

Show (URec Int p)

Since: base-4.9.0.0

Instance details

Defined in GHC.Generics

Methods

showsPrec :: Int -> URec Int p -> ShowS #

show :: URec Int p -> String #

showList :: [URec Int p] -> ShowS #

Show (URec Word p)

Since: base-4.9.0.0

Instance details

Defined in GHC.Generics

Methods

showsPrec :: Int -> URec Word p -> ShowS #

show :: URec Word p -> String #

showList :: [URec Word p] -> ShowS #

(Show e, Show1 m, Show a) => Show (ErrorT e m a) 
Instance details

Defined in Control.Monad.Trans.Error

Methods

showsPrec :: Int -> ErrorT e m a -> ShowS #

show :: ErrorT e m a -> String #

showList :: [ErrorT e m a] -> ShowS #

(Show w, Show1 m, Show a) => Show (WriterT w m a) 
Instance details

Defined in Control.Monad.Trans.Writer.Lazy

Methods

showsPrec :: Int -> WriterT w m a -> ShowS #

show :: WriterT w m a -> String #

showList :: [WriterT w m a] -> ShowS #

(Show a, Show b, Show c) => Show (a, b, c)

Since: base-2.1

Instance details

Defined in GHC.Show

Methods

showsPrec :: Int -> (a, b, c) -> ShowS #

show :: (a, b, c) -> String #

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

Show (a :~~: b)

Since: base-4.10.0.0

Instance details

Defined in Data.Type.Equality

Methods

showsPrec :: Int -> (a :~~: b) -> ShowS #

show :: (a :~~: b) -> String #

showList :: [a :~~: b] -> ShowS #

(Show (f p), Show (g p)) => Show ((f :*: g) p)

Since: base-4.7.0.0

Instance details

Defined in GHC.Generics

Methods

showsPrec :: Int -> (f :*: g) p -> ShowS #

show :: (f :*: g) p -> String #

showList :: [(f :*: g) p] -> ShowS #

(Show (f p), Show (g p)) => Show ((f :+: g) p)

Since: base-4.7.0.0

Instance details

Defined in GHC.Generics

Methods

showsPrec :: Int -> (f :+: g) p -> ShowS #

show :: (f :+: g) p -> String #

showList :: [(f :+: g) p] -> ShowS #

Show c => Show (K1 i c p)

Since: base-4.7.0.0

Instance details

Defined in GHC.Generics

Methods

showsPrec :: Int -> K1 i c p -> ShowS #

show :: K1 i c p -> String #

showList :: [K1 i c p] -> ShowS #

(Show a, Show b, Show c, Show d) => Show (a, b, c, d)

Since: base-2.1

Instance details

Defined in GHC.Show

Methods

showsPrec :: Int -> (a, b, c, d) -> ShowS #

show :: (a, b, c, d) -> String #

showList :: [(a, b, c, d)] -> ShowS #

Show (f (g p)) => Show ((f :.: g) p)

Since: base-4.7.0.0

Instance details

Defined in GHC.Generics

Methods

showsPrec :: Int -> (f :.: g) p -> ShowS #

show :: (f :.: g) p -> String #

showList :: [(f :.: g) p] -> ShowS #

Show (f p) => Show (M1 i c f p)

Since: base-4.7.0.0

Instance details

Defined in GHC.Generics

Methods

showsPrec :: Int -> M1 i c f p -> ShowS #

show :: M1 i c f p -> String #

showList :: [M1 i c f p] -> ShowS #

(Show a, Show b, Show c, Show d, Show e) => Show (a, b, c, d, e)

Since: base-2.1

Instance details

Defined in GHC.Show

Methods

showsPrec :: Int -> (a, b, c, d, e) -> ShowS #

show :: (a, b, c, d, e) -> String #

showList :: [(a, b, c, d, e)] -> ShowS #

(Show a, Show b, Show c, Show d, Show e, Show f) => Show (a, b, c, d, e, f)

Since: base-2.1

Instance details

Defined in GHC.Show

Methods

showsPrec :: Int -> (a, b, c, d, e, f) -> ShowS #

show :: (a, b, c, d, e, f) -> String #

showList :: [(a, b, c, d, e, f)] -> ShowS #

(Show a, Show b, Show c, Show d, Show e, Show f, Show g) => Show (a, b, c, d, e, f, g)

Since: base-2.1

Instance details

Defined in GHC.Show

Methods

showsPrec :: Int -> (a, b, c, d, e, f, g) -> ShowS #

show :: (a, b, c, d, e, f, g) -> String #

showList :: [(a, b, c, d, e, f, g)] -> ShowS #

(Show a, Show b, Show c, Show d, Show e, Show f, Show g, Show h) => Show (a, b, c, d, e, f, g, h)

Since: base-2.1

Instance details

Defined in GHC.Show

Methods

showsPrec :: Int -> (a, b, c, d, e, f, g, h) -> ShowS #

show :: (a, b, c, d, e, f, g, h) -> String #

showList :: [(a, b, c, d, e, f, g, h)] -> ShowS #

(Show a, Show b, Show c, Show d, Show e, Show f, Show g, Show h, Show i) => Show (a, b, c, d, e, f, g, h, i)

Since: base-2.1

Instance details

Defined in GHC.Show

Methods

showsPrec :: Int -> (a, b, c, d, e, f, g, h, i) -> ShowS #

show :: (a, b, c, d, e, f, g, h, i) -> String #

showList :: [(a, b, c, d, e, f, g, h, i)] -> ShowS #

(Show a, Show b, Show c, Show d, Show e, Show f, Show g, Show h, Show i, Show j) => Show (a, b, c, d, e, f, g, h, i, j)

Since: base-2.1

Instance details

Defined in GHC.Show

Methods

showsPrec :: Int -> (a, b, c, d, e, f, g, h, i, j) -> ShowS #

show :: (a, b, c, d, e, f, g, h, i, j) -> String #

showList :: [(a, b, c, d, e, f, g, h, i, j)] -> ShowS #

(Show a, Show b, Show c, Show d, Show e, Show f, Show g, Show h, Show i, Show j, Show k) => Show (a, b, c, d, e, f, g, h, i, j, k)

Since: base-2.1

Instance details

Defined in GHC.Show

Methods

showsPrec :: Int -> (a, b, c, d, e, f, g, h, i, j, k) -> ShowS #

show :: (a, b, c, d, e, f, g, h, i, j, k) -> String #

showList :: [(a, b, c, d, e, f, g, h, i, j, k)] -> ShowS #

(Show a, Show b, Show c, Show d, Show e, Show f, Show g, Show h, Show i, Show j, Show k, Show l) => Show (a, b, c, d, e, f, g, h, i, j, k, l)

Since: base-2.1

Instance details

Defined in GHC.Show

Methods

showsPrec :: Int -> (a, b, c, d, e, f, g, h, i, j, k, l) -> ShowS #

show :: (a, b, c, d, e, f, g, h, i, j, k, l) -> String #

showList :: [(a, b, c, d, e, f, g, h, i, j, k, l)] -> ShowS #

(Show a, Show b, Show c, Show d, Show e, Show f, Show g, Show h, Show i, Show j, Show k, Show l, Show m) => Show (a, b, c, d, e, f, g, h, i, j, k, l, m)

Since: base-2.1

Instance details

Defined in GHC.Show

Methods

showsPrec :: Int -> (a, b, c, d, e, f, g, h, i, j, k, l, m) -> ShowS #

show :: (a, b, c, d, e, f, g, h, i, j, k, l, m) -> String #

showList :: [(a, b, c, d, e, f, g, h, i, j, k, l, m)] -> ShowS #

(Show a, Show b, Show c, Show d, Show e, Show f, Show g, Show h, Show i, Show j, Show k, Show l, Show m, Show n) => Show (a, b, c, d, e, f, g, h, i, j, k, l, m, n)

Since: base-2.1

Instance details

Defined in GHC.Show

Methods

showsPrec :: Int -> (a, b, c, d, e, f, g, h, i, j, k, l, m, n) -> ShowS #

show :: (a, b, c, d, e, f, g, h, i, j, k, l, m, n) -> String #

showList :: [(a, b, c, d, e, f, g, h, i, j, k, l, m, n)] -> ShowS #

(Show a, Show b, Show c, Show d, Show e, Show f, Show g, Show h, Show i, Show j, Show k, Show l, Show m, Show n, Show o) => Show (a, b, c, d, e, f, g, h, i, j, k, l, m, n, o)

Since: base-2.1

Instance details

Defined in GHC.Show

Methods

showsPrec :: Int -> (a, b, c, d, e, f, g, h, i, j, k, l, m, n, o) -> ShowS #

show :: (a, b, c, d, e, f, g, h, i, j, k, l, m, n, o) -> String #

showList :: [(a, b, c, d, e, f, g, h, i, j, k, l, m, n, o)] -> ShowS #

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

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

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

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

fail s >>= f  =  fail s

If your Monad is also MonadPlus, a popular definition is

fail _ = mzero

Since: base-4.9.0.0

Methods

fail :: String -> m a #

Instances

Instances details
MonadFail P

Since: base-4.9.0.0

Instance details

Defined in Text.ParserCombinators.ReadP

Methods

fail :: String -> P a #

MonadFail ReadP

Since: base-4.9.0.0

Instance details

Defined in Text.ParserCombinators.ReadP

Methods

fail :: String -> ReadP a #

MonadFail DList 
Instance details

Defined in Data.DList.Internal

Methods

fail :: String -> DList a #

MonadFail IO

Since: base-4.9.0.0

Instance details

Defined in Control.Monad.Fail

Methods

fail :: String -> IO a #

MonadFail Maybe

Since: base-4.9.0.0

Instance details

Defined in Control.Monad.Fail

Methods

fail :: String -> Maybe a #

MonadFail []

Since: base-4.9.0.0

Instance details

Defined in Control.Monad.Fail

Methods

fail :: String -> [a] #

MonadFail f => MonadFail (Ap f)

Since: base-4.12.0.0

Instance details

Defined in Data.Monoid

Methods

fail :: String -> Ap f a #

(Monad m, Error e) => MonadFail (ErrorT e m) 
Instance details

Defined in Control.Monad.Trans.Error

Methods

fail :: String -> ErrorT e m a #

(Monoid w, MonadFail m) => MonadFail (WriterT w m) 
Instance details

Defined in Control.Monad.Trans.Writer.Lazy

Methods

fail :: String -> WriterT w m a #

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

A functor with application, providing operations to

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

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

(<*>) = liftA2 id
liftA2 f x y = f <$> x <*> y

Further, any definition must satisfy the following:

Identity
pure id <*> v = v
Composition
pure (.) <*> u <*> v <*> w = u <*> (v <*> w)
Homomorphism
pure f <*> pure x = pure (f x)
Interchange
u <*> pure y = pure ($ y) <*> u

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

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

It may be useful to note that supposing

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

it follows from the above that

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

If f is also a Monad, it should satisfy

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

Minimal complete definition

pure, ((<*>) | liftA2)

Methods

pure :: a -> f a #

Lift a value.

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

Sequential application.

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

Example

Expand

Used in combination with (<$>), (<*>) can be used to build a record.

>>> data MyState = MyState {arg1 :: Foo, arg2 :: Bar, arg3 :: Baz}
>>> produceFoo :: Applicative f => f Foo
>>> produceBar :: Applicative f => f Bar
>>> produceBaz :: Applicative f => f Baz
>>> mkState :: Applicative f => f MyState
>>> mkState = MyState <$> produceFoo <*> produceBar <*> produceBaz

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

Sequence actions, discarding the value of the first argument.

Examples

Expand

If used in conjunction with the Applicative instance for Maybe, you can chain Maybe computations, with a possible "early return" in case of Nothing.

>>> Just 2 *> Just 3
Just 3
>>> Nothing *> Just 3
Nothing

Of course a more interesting use case would be to have effectful computations instead of just returning pure values.

>>> import Data.Char
>>> import Text.ParserCombinators.ReadP
>>> let p = string "my name is " *> munch1 isAlpha <* eof
>>> readP_to_S p "my name is Simon"
[("Simon","")]

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

Sequence actions, discarding the value of the second argument.

Instances

Instances details
Applicative Identity

Since: base-4.8.0.0

Instance details

Defined in Data.Functor.Identity

Methods

pure :: a -> Identity a #

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

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

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

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

Applicative First

Since: base-4.8.0.0

Instance details

Defined in Data.Monoid

Methods

pure :: a -> First a #

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

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

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

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

Applicative Last

Since: base-4.8.0.0

Instance details

Defined in Data.Monoid

Methods

pure :: a -> Last a #

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

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

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

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

Applicative Down

Since: base-4.11.0.0

Instance details

Defined in Data.Ord

Methods

pure :: a -> Down a #

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

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

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

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

Applicative Dual

Since: base-4.8.0.0

Instance details

Defined in Data.Semigroup.Internal

Methods

pure :: a -> Dual a #

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

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

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

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

Applicative Product

Since: base-4.8.0.0

Instance details

Defined in Data.Semigroup.Internal

Methods

pure :: a -> Product a #

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

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

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

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

Applicative Sum

Since: base-4.8.0.0

Instance details

Defined in Data.Semigroup.Internal

Methods

pure :: a -> Sum a #

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

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

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

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

Applicative Par1

Since: base-4.9.0.0

Instance details

Defined in GHC.Generics

Methods

pure :: a -> Par1 a #

(<*>) :: Par1 (a -> b) -> Par1 a -> Par1 b #

liftA2 :: (a -> b -> c) -> Par1 a -> Par1 b -> Par1 c #

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

(<*) :: Par1 a -> Par1 b -> Par1 a #

Applicative P

Since: base-4.5.0.0

Instance details

Defined in Text.ParserCombinators.ReadP

Methods

pure :: a -> P a #

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

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

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

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

Applicative ReadP

Since: base-4.6.0.0

Instance details

Defined in Text.ParserCombinators.ReadP

Methods

pure :: a -> ReadP a #

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

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

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

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

Applicative DList 
Instance details

Defined in Data.DList.Internal

Methods

pure :: a -> DList a #

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

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

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

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

Applicative IO

Since: base-2.1

Instance details

Defined in GHC.Base

Methods

pure :: a -> IO a #

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

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

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

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

Applicative NonEmpty

Since: base-4.9.0.0

Instance details

Defined in GHC.Base

Methods

pure :: a -> NonEmpty a #

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

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

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

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

Applicative Maybe

Since: base-2.1

Instance details

Defined in GHC.Base

Methods

pure :: a -> Maybe a #

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

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

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

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

Applicative Solo

Since: base-4.15

Instance details

Defined in GHC.Base

Methods

pure :: a -> Solo a #

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

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

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

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

Applicative []

Since: base-2.1

Instance details

Defined in GHC.Base

Methods

pure :: a -> [a] #

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

liftA2 :: (a -> b -> c) -> [a] -> [b] -> [c] #

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

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

Applicative (Either e)

Since: base-3.0

Instance details

Defined in Data.Either

Methods

pure :: a -> Either e a #

(<*>) :: Either e (a -> b) -> Either e a -> Either e b #

liftA2 :: (a -> b -> c) -> Either e a -> Either e b -> Either e c #

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

(<*) :: Either e a -> Either e b -> Either e a #

Applicative (Proxy :: Type -> Type)

Since: base-4.7.0.0

Instance details

Defined in Data.Proxy

Methods

pure :: a -> Proxy a #

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

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

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

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

Applicative (U1 :: Type -> Type)

Since: base-4.9.0.0

Instance details

Defined in GHC.Generics

Methods

pure :: a -> U1 a #

(<*>) :: U1 (a -> b) -> U1 a -> U1 b #

liftA2 :: (a -> b -> c) -> U1 a -> U1 b -> U1 c #

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

(<*) :: U1 a -> U1 b -> U1 a #

Applicative (ProofScheme a) 
Instance details

Defined in Copilot.Theorem.Prove

Methods

pure :: a0 -> ProofScheme a a0 #

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

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

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

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

Monoid a => Applicative ((,) a)

For tuples, the Monoid constraint on a determines how the first values merge. For example, Strings concatenate:

("hello ", (+15)) <*> ("world!", 2002)
("hello world!",2017)

Since: base-2.1

Instance details

Defined in GHC.Base

Methods

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

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

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

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

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

Applicative f => Applicative (Ap f)

Since: base-4.12.0.0

Instance details

Defined in Data.Monoid

Methods

pure :: a -> Ap f a #

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

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

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

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

Applicative f => Applicative (Alt f)

Since: base-4.8.0.0

Instance details

Defined in Data.Semigroup.Internal

Methods

pure :: a -> Alt f a #

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

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

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

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

Applicative f => Applicative (Rec1 f)

Since: base-4.9.0.0

Instance details

Defined in GHC.Generics

Methods

pure :: a -> Rec1 f a #

(<*>) :: Rec1 f (a -> b) -> Rec1 f a -> Rec1 f b #

liftA2 :: (a -> b -> c) -> Rec1 f a -> Rec1 f b -> Rec1 f c #

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

(<*) :: Rec1 f a -> Rec1 f b -> Rec1 f a #

(Applicative f, Monad f) => Applicative (WhenMissing f x)

Equivalent to ReaderT k (ReaderT x (MaybeT f)).

Since: containers-0.5.9

Instance details

Defined in Data.IntMap.Internal

Methods

pure :: a -> WhenMissing f x a #

(<*>) :: WhenMissing f x (a -> b) -> WhenMissing f x a -> WhenMissing f x b #

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

(*>) :: WhenMissing f x a -> WhenMissing f x b -> WhenMissing f x b #

(<*) :: WhenMissing f x a -> WhenMissing f x b -> WhenMissing f x a #

(Functor m, Monad m) => Applicative (ErrorT e m) 
Instance details

Defined in Control.Monad.Trans.Error

Methods

pure :: a -> ErrorT e m a #

(<*>) :: ErrorT e m (a -> b) -> ErrorT e m a -> ErrorT e m b #

liftA2 :: (a -> b -> c) -> ErrorT e m a -> ErrorT e m b -> ErrorT e m c #

(*>) :: ErrorT e m a -> ErrorT e m b -> ErrorT e m b #

(<*) :: ErrorT e m a -> ErrorT e m b -> ErrorT e m a #

(Monoid w, Applicative m) => Applicative (WriterT w m) 
Instance details

Defined in Control.Monad.Trans.Writer.Lazy

Methods

pure :: a -> WriterT w m a #

(<*>) :: WriterT w m (a -> b) -> WriterT w m a -> WriterT w m b #

liftA2 :: (a -> b -> c) -> WriterT w m a -> WriterT w m b -> WriterT w m c #

(*>) :: WriterT w m a -> WriterT w m b -> WriterT w m b #

(<*) :: WriterT w m a -> WriterT w m b -> WriterT w m a #

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

Since: base-4.14.0.0

Instance details

Defined in GHC.Base

Methods

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

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

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

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

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

(Applicative f, Applicative g) => Applicative (f :*: g)

Since: base-4.9.0.0

Instance details

Defined in GHC.Generics

Methods

pure :: a -> (f :*: g) a #

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

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

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

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

Monoid c => Applicative (K1 i c :: Type -> Type)

Since: base-4.12.0.0

Instance details

Defined in GHC.Generics

Methods

pure :: a -> K1 i c a #

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

liftA2 :: (a -> b -> c0) -> K1 i c a -> K1 i c b -> K1 i c c0 #

(*>) :: K1 i c a -> K1 i c b -> K1 i c b #

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

(Monad f, Applicative f) => Applicative (WhenMatched f x y)

Equivalent to ReaderT Key (ReaderT x (ReaderT y (MaybeT f)))

Since: containers-0.5.9

Instance details

Defined in Data.IntMap.Internal

Methods

pure :: a -> WhenMatched f x y a #

(<*>) :: WhenMatched f x y (a -> b) -> WhenMatched f x y a -> WhenMatched f x y b #

liftA2 :: (a -> b -> c) -> WhenMatched f x y a -> WhenMatched f x y b -> WhenMatched f x y c #

(*>) :: WhenMatched f x y a -> WhenMatched f x y b -> WhenMatched f x y b #

(<*) :: WhenMatched f x y a -> WhenMatched f x y b -> WhenMatched f x y a #

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

Since: base-4.14.0.0

Instance details

Defined in GHC.Base

Methods

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

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

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

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

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

Applicative ((->) r)

Since: base-2.1

Instance details

Defined in GHC.Base

Methods

pure :: a -> r -> a #

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

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

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

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

(Applicative f, Applicative g) => Applicative (f :.: g)

Since: base-4.9.0.0

Instance details

Defined in GHC.Generics

Methods

pure :: a -> (f :.: g) a #

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

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

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

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

Applicative f => Applicative (M1 i c f)

Since: base-4.9.0.0

Instance details

Defined in GHC.Generics

Methods

pure :: a -> M1 i c f a #

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

liftA2 :: (a -> b -> c0) -> M1 i c f a -> M1 i c f b -> M1 i c f c0 #

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

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

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

The Foldable class represents data structures that can be reduced to a summary value one element at a time. Strict left-associative folds are a good fit for space-efficient reduction, while lazy right-associative folds are a good fit for corecursive iteration, or for folds that short-circuit after processing an initial subsequence of the structure's elements.

Instances can be derived automatically by enabling the DeriveFoldable extension. For example, a derived instance for a binary tree might be:

{-# LANGUAGE DeriveFoldable #-}
data Tree a = Empty
            | Leaf a
            | Node (Tree a) a (Tree a)
    deriving Foldable

A more detailed description can be found in the Overview section of Data.Foldable.

For the class laws see the Laws section of Data.Foldable.

Minimal complete definition

foldMap | foldr

Methods

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

Map each element of the structure into a monoid, and combine the results with (<>). This fold is right-associative and lazy in the accumulator. For strict left-associative folds consider foldMap' instead.

Examples

Expand

Basic usage:

>>> foldMap Sum [1, 3, 5]
Sum {getSum = 9}
>>> foldMap Product [1, 3, 5]
Product {getProduct = 15}
>>> foldMap (replicate 3) [1, 2, 3]
[1,1,1,2,2,2,3,3,3]

When a Monoid's (<>) is lazy in its second argument, foldMap can return a result even from an unbounded structure. For example, lazy accumulation enables Data.ByteString.Builder to efficiently serialise large data structures and produce the output incrementally:

>>> import qualified Data.ByteString.Lazy as L
>>> import qualified Data.ByteString.Builder as B
>>> let bld :: Int -> B.Builder; bld i = B.intDec i <> B.word8 0x20
>>> let lbs = B.toLazyByteString $ foldMap bld [0..]
>>> L.take 64 lbs
"0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24"

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

Right-associative fold of a structure, lazy in the accumulator.

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, given an operator lazy in its right argument, foldr can produce a terminating expression from an unbounded list.

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

foldr f z = foldr f z . toList

Examples

Expand

Basic usage:

>>> foldr (||) False [False, True, False]
True
>>> foldr (||) False []
False
>>> foldr (\c acc -> acc ++ [c]) "foo" ['a', 'b', 'c', 'd']
"foodcba"
Infinite structures

⚠️ Applying foldr to infinite structures usually doesn't terminate.

It may still terminate under one of the following conditions:

  • the folding function is short-circuiting
  • the folding function is lazy on its second argument
Short-circuiting

(||) short-circuits on True values, so the following terminates because there is a True value finitely far from the left side:

>>> foldr (||) False (True : repeat False)
True

But the following doesn't terminate:

>>> foldr (||) False (repeat False ++ [True])
* Hangs forever *
Laziness in the second argument

Applying foldr to infinite structures terminates when the operator is lazy in its second argument (the initial accumulator is never used in this case, and so could be left undefined, but [] is more clear):

>>> take 5 $ foldr (\i acc -> i : fmap (+3) acc) [] (repeat 1)
[1,4,7,10,13]

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

Left-associative fold of a structure, lazy in the accumulator. This is rarely what you want, but can work well for structures with efficient right-to-left sequencing and an operator that is lazy in its left argument.

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

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

Note that to produce the outermost application of the operator the entire input list must be traversed. Like all left-associative folds, foldl will diverge if given an infinite list.

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

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

foldl f z = foldl f z . toList

Examples

Expand

The first example is a strict fold, which in practice is best performed with foldl'.

>>> foldl (+) 42 [1,2,3,4]
52

Though the result below is lazy, the input is reversed before prepending it to the initial accumulator, so corecursion begins only after traversing the entire input string.

>>> foldl (\acc c -> c : acc) "abcd" "efgh"
"hgfeabcd"

A left fold of a structure that is infinite on the right cannot terminate, even when for any finite input the fold just returns the initial accumulator:

>>> foldl (\a _ -> a) 0 $ repeat 1
* Hangs forever *

WARNING: When it comes to lists, you always want to use either foldl' or foldr instead.

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

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

This function is non-total and will raise a runtime exception if the structure happens to be empty.

Examples

Expand

Basic usage:

>>> foldr1 (+) [1..4]
10
>>> foldr1 (+) []
Exception: Prelude.foldr1: empty list
>>> foldr1 (+) Nothing
*** Exception: foldr1: empty structure
>>> foldr1 (-) [1..4]
-2
>>> foldr1 (&&) [True, False, True, True]
False
>>> foldr1 (||) [False, False, True, True]
True
>>> foldr1 (+) [1..]
* Hangs forever *

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

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

This function is non-total and will raise a runtime exception if the structure happens to be empty.

foldl1 f = foldl1 f . toList

Examples

Expand

Basic usage:

>>> foldl1 (+) [1..4]
10
>>> foldl1 (+) []
*** Exception: Prelude.foldl1: empty list
>>> foldl1 (+) Nothing
*** Exception: foldl1: empty structure
>>> foldl1 (-) [1..4]
-8
>>> foldl1 (&&) [True, False, True, True]
False
>>> foldl1 (||) [False, False, True, True]
True
>>> foldl1 (+) [1..]
* Hangs forever *

null :: t a -> Bool #

Test whether the structure is empty. The default implementation is Left-associative and lazy in both the initial element and the accumulator. Thus optimised for structures where the first element can be accessed in constant time. Structures where this is not the case should have a non-default implementation.

Examples

Expand

Basic usage:

>>> null []
True
>>> null [1]
False

null is expected to terminate even for infinite structures. The default implementation terminates provided the structure is bounded on the left (there is a leftmost element).

>>> null [1..]
False

Since: base-4.8.0.0

length :: t a -> Int #

Returns the size/length of a finite structure as an Int. The default implementation just counts elements starting with the leftmost. Instances for structures that can compute the element count faster than via element-by-element counting, should provide a specialised implementation.

Examples

Expand

Basic usage:

>>> length []
0
>>> length ['a', 'b', 'c']
3
>>> length [1..]
* Hangs forever *

Since: base-4.8.0.0

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

Does the element occur in the structure?

Note: elem is often used in infix form.

Examples

Expand

Basic usage:

>>> 3 `elem` []
False
>>> 3 `elem` [1,2]
False
>>> 3 `elem` [1,2,3,4,5]
True

For infinite structures, the default implementation of elem terminates if the sought-after value exists at a finite distance from the left side of the structure:

>>> 3 `elem` [1..]
True
>>> 3 `elem` ([4..] ++ [3])
* Hangs forever *

Since: base-4.8.0.0

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

The largest element of a non-empty structure.

This function is non-total and will raise a runtime exception if the structure happens to be empty. A structure that supports random access and maintains its elements in order should provide a specialised implementation to return the maximum in faster than linear time.

Examples

Expand

Basic usage:

>>> maximum [1..10]
10
>>> maximum []
*** Exception: Prelude.maximum: empty list
>>> maximum Nothing
*** Exception: maximum: empty structure

WARNING: This function is partial for possibly-empty structures like lists.

Since: base-4.8.0.0

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

The least element of a non-empty structure.

This function is non-total and will raise a runtime exception if the structure happens to be empty. A structure that supports random access and maintains its elements in order should provide a specialised implementation to return the minimum in faster than linear time.

Examples

Expand

Basic usage:

>>> minimum [1..10]
1
>>> minimum []
*** Exception: Prelude.minimum: empty list
>>> minimum Nothing
*** Exception: minimum: empty structure

WARNING: This function is partial for possibly-empty structures like lists.

Since: base-4.8.0.0

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

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

Examples

Expand

Basic usage:

>>> product []
1
>>> product [42]
42
>>> product [1..10]
3628800
>>> product [4.1, 2.0, 1.7]
13.939999999999998
>>> product [1..]
* Hangs forever *

Since: base-4.8.0.0

Instances

Instances details
Foldable Identity

Since: base-4.8.0.0

Instance details

Defined in Data.Functor.Identity

Methods

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

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

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

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

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

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

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

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

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

toList :: Identity a -> [a] #

null :: Identity a -> Bool #

length :: Identity a -> Int #

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

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

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

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

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

Foldable First

Since: base-4.8.0.0

Instance details

Defined in Data.Foldable

Methods

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

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

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

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

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

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

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

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

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

toList :: First a -> [a] #

null :: First a -> Bool #

length :: First a -> Int #

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

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

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

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

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

Foldable Last

Since: base-4.8.0.0

Instance details

Defined in Data.Foldable

Methods

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

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

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

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

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

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

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

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

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

toList :: Last a -> [a] #

null :: Last a -> Bool #

length :: Last a -> Int #

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

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

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

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

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

Foldable Down

Since: base-4.12.0.0

Instance details

Defined in Data.Foldable

Methods

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

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

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

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

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

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

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

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

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

toList :: Down a -> [a] #

null :: Down a -> Bool #

length :: Down a -> Int #

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

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

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

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

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

Foldable Dual

Since: base-4.8.0.0

Instance details

Defined in Data.Foldable

Methods

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

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

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

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

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

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

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

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

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

toList :: Dual a -> [a] #

null :: Dual a -> Bool #

length :: Dual a -> Int #

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

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

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

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

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

Foldable Product

Since: base-4.8.0.0

Instance details

Defined in Data.Foldable

Methods

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

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

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

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

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

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

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

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

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

toList :: Product a -> [a] #

null :: Product a -> Bool #

length :: Product a -> Int #

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

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

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

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

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

Foldable Sum

Since: base-4.8.0.0

Instance details

Defined in Data.Foldable

Methods

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

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

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

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

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

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

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

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

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

toList :: Sum a -> [a] #

null :: Sum a -> Bool #

length :: Sum a -> Int #

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

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

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

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

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

Foldable Par1

Since: base-4.9.0.0

Instance details

Defined in Data.Foldable

Methods

fold :: Monoid m => Par1 m -> m #

foldMap :: Monoid m => (a -> m) -> Par1 a -> m #

foldMap' :: Monoid m => (a -> m) -> Par1 a -> m #

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

foldr' :: (a -> b -> b) -> b -> Par1 a -> b #

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

foldl' :: (b -> a -> b) -> b -> Par1 a -> b #

foldr1 :: (a -> a -> a) -> Par1 a -> a #

foldl1 :: (a -> a -> a) -> Par1 a -> a #

toList :: Par1 a -> [a] #

null :: Par1 a -> Bool #

length :: Par1 a -> Int #

elem :: Eq a => a -> Par1 a -> Bool #

maximum :: Ord a => Par1 a -> a #

minimum :: Ord a => Par1 a -> a #

sum :: Num a => Par1 a -> a #

product :: Num a => Par1 a -> a #

Foldable IntMap

Folds in order of increasing key.

Instance details

Defined in Data.IntMap.Internal

Methods

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

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

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

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

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

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

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

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

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

toList :: IntMap a -> [a] #

null :: IntMap a -> Bool #

length :: IntMap a -> Int #

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

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

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

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

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

Foldable DList 
Instance details

Defined in Data.DList.Internal

Methods

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

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

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

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

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

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

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

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

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

toList :: DList a -> [a] #

null :: DList a -> Bool #

length :: DList a -> Int #

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

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

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

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

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

Foldable NonEmpty

Since: base-4.9.0.0

Instance details

Defined in Data.Foldable

Methods

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

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

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

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

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

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

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

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

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

toList :: NonEmpty a -> [a] #

null :: NonEmpty a -> Bool #

length :: NonEmpty a -> Int #

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

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

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

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

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

Foldable Maybe

Since: base-2.1

Instance details

Defined in Data.Foldable

Methods

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

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

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

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

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

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

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

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

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

toList :: Maybe a -> [a] #

null :: Maybe a -> Bool #

length :: Maybe a -> Int #

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

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

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

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

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

Foldable Solo

Since: base-4.15

Instance details

Defined in Data.Foldable

Methods

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

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

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

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

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

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

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

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

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

toList :: Solo a -> [a] #

null :: Solo a -> Bool #

length :: Solo a -> Int #

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

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

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

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

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

Foldable []

Since: base-2.1

Instance details

Defined in Data.Foldable

Methods

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

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

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

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

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

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

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

foldr1 :: (a -> a -> a) -> [a] -> a #

foldl1 :: (a -> a -> a) -> [a] -> a #

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

null :: [a] -> Bool #

length :: [a] -> Int #

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

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

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

sum :: Num a => [a] -> a #

product :: Num a => [a] -> a #

Foldable (Either a)

Since: base-4.7.0.0

Instance details

Defined in Data.Foldable

Methods

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

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

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

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

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

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

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

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

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

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

null :: Either a a0 -> Bool #

length :: Either a a0 -> Int #

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

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

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

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

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

Foldable (Proxy :: TYPE LiftedRep -> Type)

Since: base-4.7.0.0

Instance details

Defined in Data.Foldable

Methods

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

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

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

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

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

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

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

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

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

toList :: Proxy a -> [a] #

null :: Proxy a -> Bool #

length :: Proxy a -> Int #

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

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

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

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

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

Foldable (Array i)

Since: base-4.8.0.0

Instance details

Defined in Data.Foldable

Methods

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

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

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

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

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

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

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

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

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

toList :: Array i a -> [a] #

null :: Array i a -> Bool #

length :: Array i a -> Int #

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

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

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

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

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

Foldable (U1 :: TYPE LiftedRep -> Type)

Since: base-4.9.0.0

Instance details

Defined in Data.Foldable

Methods

fold :: Monoid m => U1 m -> m #

foldMap :: Monoid m => (a -> m) -> U1 a -> m #

foldMap' :: Monoid m => (a -> m) -> U1 a -> m #

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

foldr' :: (a -> b -> b) -> b -> U1 a -> b #

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

foldl' :: (b -> a -> b) -> b -> U1 a -> b #

foldr1 :: (a -> a -> a) -> U1 a -> a #

foldl1 :: (a -> a -> a) -> U1 a -> a #

toList :: U1 a -> [a] #

null :: U1 a -> Bool #

length :: U1 a -> Int #

elem :: Eq a => a -> U1 a -> Bool #

maximum :: Ord a => U1 a -> a #

minimum :: Ord a => U1 a -> a #

sum :: Num a => U1 a -> a #

product :: Num a => U1 a -> a #

Foldable (UAddr :: TYPE LiftedRep -> Type)

Since: base-4.9.0.0

Instance details

Defined in Data.Foldable

Methods

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

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

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

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

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

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

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

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

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

toList :: UAddr a -> [a] #

null :: UAddr a -> Bool #

length :: UAddr a -> Int #

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

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

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

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

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

Foldable (UChar :: TYPE LiftedRep -> Type)

Since: base-4.9.0.0

Instance details

Defined in Data.Foldable

Methods

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

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

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

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

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

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

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

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

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

toList :: UChar a -> [a] #

null :: UChar a -> Bool #

length :: UChar a -> Int #

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

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

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

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

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

Foldable (UDouble :: TYPE LiftedRep -> Type)

Since: base-4.9.0.0

Instance details

Defined in Data.Foldable

Methods

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

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

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

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

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

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

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

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

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

toList :: UDouble a -> [a] #

null :: UDouble a -> Bool #

length :: UDouble a -> Int #

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

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

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

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

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

Foldable (UFloat :: TYPE LiftedRep -> Type)

Since: base-4.9.0.0

Instance details

Defined in Data.Foldable

Methods

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

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

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

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

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

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

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

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

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

toList :: UFloat a -> [a] #

null :: UFloat a -> Bool #

length :: UFloat a -> Int #

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

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

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

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

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

Foldable (UInt :: TYPE LiftedRep -> Type)

Since: base-4.9.0.0

Instance details

Defined in Data.Foldable

Methods

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

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

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

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

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

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

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

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

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

toList :: UInt a -> [a] #

null :: UInt a -> Bool #

length :: UInt a -> Int #

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

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

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

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

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

Foldable (UWord :: TYPE LiftedRep -> Type)

Since: base-4.9.0.0

Instance details

Defined in Data.Foldable

Methods

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

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

foldMap' :: Monoid m => (a -> m) -> UWord a -> m #

foldr :: (a -> b -> b) -> b -> UWord a -> b #

foldr' :: (a -> b -> b) -> b -> UWord a -> b #

foldl :: (b -> a -> b) -> b -> UWord a -> b #

foldl' :: (b -> a -> b) -> b -> UWord a -> b #

foldr1 :: (a -> a -> a) -> UWord a -> a #

foldl1 :: (a -> a -> a) -> UWord a -> a #

toList :: UWord a -> [a] #

null :: UWord a -> Bool #

length :: UWord a -> Int #

elem :: Eq a => a -> UWord a -> Bool #

maximum :: Ord a => UWord a -> a #

minimum :: Ord a => UWord a -> a #

sum :: Num a => UWord a -> a #

product :: Num a => UWord a -> a #

Foldable (V1 :: TYPE LiftedRep -> Type)

Since: base-4.9.0.0

Instance details

Defined in Data.Foldable

Methods

fold :: Monoid m => V1 m -> m #

foldMap :: Monoid m => (a -> m) -> V1 a -> m #

foldMap' :: Monoid m => (a -> m) -> V1 a -> m #

foldr :: (a -> b -> b) -> b -> V1 a -> b #

foldr' :: (a -> b -> b) -> b -> V1 a -> b #

foldl :: (b -> a -> b) -> b -> V1 a -> b #

foldl' :: (b -> a -> b) -> b -> V1 a -> b #

foldr1 :: (a -> a -> a) -> V1 a -> a #

foldl1 :: (a -> a -> a) -> V1 a -> a #

toList :: V1 a -> [a] #

null :: V1 a -> Bool #

length :: V1 a -> Int #

elem :: Eq a => a -> V1 a -> Bool #

maximum :: Ord a => V1 a -> a #

minimum :: Ord a => V1 a -> a #

sum :: Num a => V1 a -> a #

product :: Num a => V1 a -> a #

Foldable (Array n)

This instance is deprecated in Copilot 3.11.

Instance details

Defined in Copilot.Core.Type.Array

Methods

fold :: Monoid m => Array n m -> m #

foldMap :: Monoid m => (a -> m) -> Array n a -> m #

foldMap' :: Monoid m => (a -> m) -> Array n a -> m #

foldr :: (a -> b -> b) -> b -> Array n a -> b #

foldr' :: (a -> b -> b) -> b -> Array n a -> b #

foldl :: (b -> a -> b) -> b -> Array n a -> b #

foldl' :: (b -> a -> b) -> b -> Array n a -> b #

foldr1 :: (a -> a -> a) -> Array n a -> a #

foldl1 :: (a -> a -> a) -> Array n a -> a #

toList :: Array n a -> [a] #

null :: Array n a -> Bool #

length :: Array n a -> Int #

elem :: Eq a => a -> Array n a -> Bool #

maximum :: Ord a => Array n a -> a #

minimum :: Ord a => Array n a -> a #

sum :: Num a => Array n a -> a #

product :: Num a => Array n a -> a #

Foldable ((,) a)

Since: base-4.7.0.0

Instance details

Defined in Data.Foldable

Methods

fold :: Monoid m => (a, m) -> m #

foldMap :: Monoid m => (a0 -> m) -> (a, a0) -> m #

foldMap' :: Monoid m => (a0 -> m) -> (a, a0) -> m #

foldr :: (a0 -> b -> b) -> b -> (a, a0) -> b #

foldr' :: (a0 -> b -> b) -> b -> (a, a0) -> b #

foldl :: (b -> a0 -> b) -> b -> (a, a0) -> b #

foldl' :: (b -> a0 -> b) -> b -> (a, a0) -> b #

foldr1 :: (a0 -> a0 -> a0) -> (a, a0) -> a0 #

foldl1 :: (a0 -> a0 -> a0) -> (a, a0) -> a0 #

toList :: (a, a0) -> [a0] #

null :: (a, a0) -> Bool #

length :: (a, a0) -> Int #

elem :: Eq a0 => a0 -> (a, a0) -> Bool #

maximum :: Ord a0 => (a, a0) -> a0 #

minimum :: Ord a0 => (a, a0) -> a0 #

sum :: Num a0 => (a, a0) -> a0 #

product :: Num a0 => (a, a0) -> a0 #

Foldable f => Foldable (Ap f)

Since: base-4.12.0.0

Instance details

Defined in Data.Foldable

Methods

fold :: Monoid m => Ap f m -> m #

foldMap :: Monoid m => (a -> m) -> Ap f a -> m #

foldMap' :: Monoid m => (a -> m) -> Ap f a -> m #

foldr :: (a -> b -> b) -> b -> Ap f a -> b #

foldr' :: (a -> b -> b) -> b -> Ap f a -> b #

foldl :: (b -> a -> b) -> b -> Ap f a -> b #

foldl' :: (b -> a -> b) -> b -> Ap f a -> b #

foldr1 :: (a -> a -> a) -> Ap f a -> a #

foldl1 :: (a -> a -> a) -> Ap f a -> a #

toList :: Ap f a -> [a] #

null :: Ap f a -> Bool #

length :: Ap f a -> Int #

elem :: Eq a => a -> Ap f a -> Bool #

maximum :: Ord a => Ap f a -> a #

minimum :: Ord a => Ap f a -> a #

sum :: Num a => Ap f a -> a #

product :: Num a => Ap f a -> a #

Foldable f => Foldable (Alt f)

Since: base-4.12.0.0

Instance details

Defined in Data.Foldable

Methods

fold :: Monoid m => Alt f m -> m #

foldMap :: Monoid m => (a -> m) -> Alt f a -> m #

foldMap' :: Monoid m => (a -> m) -> Alt f a -> m #

foldr :: (a -> b -> b) -> b -> Alt f a -> b #

foldr' :: (a -> b -> b) -> b -> Alt f a -> b #

foldl :: (b -> a -> b) -> b -> Alt f a -> b #

foldl' :: (b -> a -> b) -> b -> Alt f a -> b #

foldr1 :: (a -> a -> a) -> Alt f a -> a #

foldl1 :: (a -> a -> a) -> Alt f a -> a #

toList :: Alt f a -> [a] #

null :: Alt f a -> Bool #

length :: Alt f a -> Int #

elem :: Eq a => a -> Alt f a -> Bool #

maximum :: Ord a => Alt f a -> a #

minimum :: Ord a => Alt f a -> a #

sum :: Num a => Alt f a -> a #

product :: Num a => Alt f a -> a #

Foldable f => Foldable (Rec1 f)

Since: base-4.9.0.0

Instance details

Defined in Data.Foldable

Methods

fold :: Monoid m => Rec1 f m -> m #

foldMap :: Monoid m => (a -> m) -> Rec1 f a -> m #

foldMap' :: Monoid m => (a -> m) -> Rec1 f a -> m #

foldr :: (a -> b -> b) -> b -> Rec1 f a -> b #

foldr' :: (a -> b -> b) -> b -> Rec1 f a -> b #

foldl :: (b -> a -> b) -> b -> Rec1 f a -> b #

foldl' :: (b -> a -> b) -> b -> Rec1 f a -> b #

foldr1 :: (a -> a -> a) -> Rec1 f a -> a #

foldl1 :: (a -> a -> a) -> Rec1 f a -> a #

toList :: Rec1 f a -> [a] #

null :: Rec1 f a -> Bool #

length :: Rec1 f a -> Int #

elem :: Eq a => a -> Rec1 f a -> Bool #

maximum :: Ord a => Rec1 f a -> a #

minimum :: Ord a => Rec1 f a -> a #

sum :: Num a => Rec1 f a -> a #

product :: Num a => Rec1 f a -> a #

Foldable f => Foldable (ErrorT e f) 
Instance details

Defined in Control.Monad.Trans.Error

Methods

fold :: Monoid m => ErrorT e f m -> m #

foldMap :: Monoid m => (a -> m) -> ErrorT e f a -> m #

foldMap' :: Monoid m => (a -> m) -> ErrorT e f a -> m #

foldr :: (a -> b -> b) -> b -> ErrorT e f a -> b #

foldr' :: (a -> b -> b) -> b -> ErrorT e f a -> b #

foldl :: (b -> a -> b) -> b -> ErrorT e f a -> b #

foldl' :: (b -> a -> b) -> b -> ErrorT e f a -> b #

foldr1 :: (a -> a -> a) -> ErrorT e f a -> a #

foldl1 :: (a -> a -> a) -> ErrorT e f a -> a #

toList :: ErrorT e f a -> [a] #

null :: ErrorT e f a -> Bool #

length :: ErrorT e f a -> Int #

elem :: Eq a => a -> ErrorT e f a -> Bool #

maximum :: Ord a => ErrorT e f a -> a #

minimum :: Ord a => ErrorT e f a -> a #

sum :: Num a => ErrorT e f a -> a #

product :: Num a => ErrorT e f a -> a #

Foldable f => Foldable (WriterT w f) 
Instance details

Defined in Control.Monad.Trans.Writer.Lazy

Methods

fold :: Monoid m => WriterT w f m -> m #

foldMap :: Monoid m => (a -> m) -> WriterT w f a -> m #

foldMap' :: Monoid m => (a -> m) -> WriterT w f a -> m #

foldr :: (a -> b -> b) -> b -> WriterT w f a -> b #

foldr' :: (a -> b -> b) -> b -> WriterT w f a -> b #

foldl :: (b -> a -> b) -> b -> WriterT w f a -> b #

foldl' :: (b -> a -> b) -> b -> WriterT w f a -> b #

foldr1 :: (a -> a -> a) -> WriterT w f a -> a #

foldl1 :: (a -> a -> a) -> WriterT w f a -> a #

toList :: WriterT w f a -> [a] #

null :: WriterT w f a -> Bool #

length :: WriterT w f a -> Int #

elem :: Eq a => a -> WriterT w f a -> Bool #

maximum :: Ord a => WriterT w f a -> a #

minimum :: Ord a => WriterT w f a -> a #

sum :: Num a => WriterT w f a -> a #

product :: Num a => WriterT w f a -> a #

(Foldable f, Foldable g) => Foldable (f :*: g)

Since: base-4.9.0.0

Instance details

Defined in Data.Foldable

Methods

fold :: Monoid m => (f :*: g) m -> m #

foldMap :: Monoid m => (a -> m) -> (f :*: g) a -> m #

foldMap' :: Monoid m => (a -> m) -> (f :*: g) a -> m #

foldr :: (a -> b -> b) -> b -> (f :*: g) a -> b #

foldr' :: (a -> b -> b) -> b -> (f :*: g) a -> b #

foldl :: (b -> a -> b) -> b -> (f :*: g) a -> b #

foldl' :: (b -> a -> b) -> b -> (f :*: g) a -> b #

foldr1 :: (a -> a -> a) -> (f :*: g) a -> a #

foldl1 :: (a -> a -> a) -> (f :*: g) a -> a #

toList :: (f :*: g) a -> [a] #

null :: (f :*: g) a -> Bool #

length :: (f :*: g) a -> Int #

elem :: Eq a => a -> (f :*: g) a -> Bool #

maximum :: Ord a => (f :*: g) a -> a #

minimum :: Ord a => (f :*: g) a -> a #

sum :: Num a => (f :*: g) a -> a #

product :: Num a => (f :*: g) a -> a #

(Foldable f, Foldable g) => Foldable (f :+: g)

Since: base-4.9.0.0

Instance details

Defined in Data.Foldable

Methods

fold :: Monoid m => (f :+: g) m -> m #

foldMap :: Monoid m => (a -> m) -> (f :+: g) a -> m #

foldMap' :: Monoid m => (a -> m) -> (f :+: g) a -> m #

foldr :: (a -> b -> b) -> b -> (f :+: g) a -> b #

foldr' :: (a -> b -> b) -> b -> (f :+: g) a -> b #

foldl :: (b -> a -> b) -> b -> (f :+: g) a -> b #

foldl' :: (b -> a -> b) -> b -> (f :+: g) a -> b #

foldr1 :: (a -> a -> a) -> (f :+: g) a -> a #

foldl1 :: (a -> a -> a) -> (f :+: g) a -> a #

toList :: (f :+: g) a -> [a] #

null :: (f :+: g) a -> Bool #

length :: (f :+: g) a -> Int #

elem :: Eq a => a -> (f :+: g) a -> Bool #

maximum :: Ord a => (f :+: g) a -> a #

minimum :: Ord a => (f :+: g) a -> a #

sum :: Num a => (f :+: g) a -> a #

product :: Num a => (f :+: g) a -> a #

Foldable (K1 i c :: TYPE LiftedRep -> Type)

Since: base-4.9.0.0

Instance details

Defined in Data.Foldable

Methods

fold :: Monoid m => K1 i c m -> m #

foldMap :: Monoid m => (a -> m) -> K1 i c a -> m #

foldMap' :: Monoid m => (a -> m) -> K1 i c a -> m #

foldr :: (a -> b -> b) -> b -> K1 i c a -> b #

foldr' :: (a -> b -> b) -> b -> K1 i c a -> b #

foldl :: (b -> a -> b) -> b -> K1 i c a -> b #

foldl' :: (b -> a -> b) -> b -> K1 i c a -> b #

foldr1 :: (a -> a -> a) -> K1 i c a -> a #

foldl1 :: (a -> a -> a) -> K1 i c a -> a #

toList :: K1 i c a -> [a] #

null :: K1 i c a -> Bool #

length :: K1 i c a -> Int #

elem :: Eq a => a -> K1 i c a -> Bool #

maximum :: Ord a => K1 i c a -> a #

minimum :: Ord a => K1 i c a -> a #

sum :: Num a => K1 i c a -> a #

product :: Num a => K1 i c a -> a #

(Foldable f, Foldable g) => Foldable (f :.: g)

Since: base-4.9.0.0

Instance details

Defined in Data.Foldable

Methods

fold :: Monoid m => (f :.: g) m -> m #

foldMap :: Monoid m => (a -> m) -> (f :.: g) a -> m #

foldMap' :: Monoid m => (a -> m) -> (f :.: g) a -> m #

foldr :: (a -> b -> b) -> b -> (f :.: g) a -> b #

foldr' :: (a -> b -> b) -> b -> (f :.: g) a -> b #

foldl :: (b -> a -> b) -> b -> (f :.: g) a -> b #

foldl' :: (b -> a -> b) -> b -> (f :.: g) a -> b #

foldr1 :: (a -> a -> a) -> (f :.: g) a -> a #

foldl1 :: (a -> a -> a) -> (f :.: g) a -> a #

toList :: (f :.: g) a -> [a] #

null :: (f :.: g) a -> Bool #

length :: (f :.: g) a -> Int #

elem :: Eq a => a -> (f :.: g) a -> Bool #

maximum :: Ord a => (f :.: g) a -> a #

minimum :: Ord a => (f :.: g) a -> a #

sum :: Num a => (f :.: g) a -> a #

product :: Num a => (f :.: g) a -> a #

Foldable f => Foldable (M1 i c f)

Since: base-4.9.0.0

Instance details

Defined in Data.Foldable

Methods

fold :: Monoid m => M1 i c f m -> m #

foldMap :: Monoid m => (a -> m) -> M1 i c f a -> m #

foldMap' :: Monoid m => (a -> m) -> M1 i c f a -> m #

foldr :: (a -> b -> b) -> b -> M1 i c f a -> b #

foldr' :: (a -> b -> b) -> b -> M1 i c f a -> b #

foldl :: (b -> a -> b) -> b -> M1 i c f a -> b #

foldl' :: (b -> a -> b) -> b -> M1 i c f a -> b #

foldr1 :: (a -> a -> a) -> M1 i c f a -> a #

foldl1 :: (a -> a -> a) -> M1 i c f a -> a #

toList :: M1 i c f a -> [a] #

null :: M1 i c f a -> Bool #

length :: M1 i c f a -> Int #

elem :: Eq a => a -> M1 i c f a -> Bool #

maximum :: Ord a => M1 i c f a -> a #

minimum :: Ord a => M1 i c f a -> a #

sum :: Num a => M1 i c f a -> a #

product :: Num a => M1 i c f a -> a #

class (Functor t, Foldable t) => Traversable (t :: Type -> Type) where #

Functors representing data structures that can be transformed to structures of the same shape by performing an Applicative (or, therefore, Monad) action on each element from left to right.

A more detailed description of what same shape means, the various methods, how traversals are constructed, and example advanced use-cases can be found in the Overview section of Data.Traversable.

For the class laws see the Laws section of Data.Traversable.

Minimal complete definition

traverse | sequenceA

Methods

traverse :: Applicative f => (a -> f b) -> t a -> f (t b) #

Map each element of a structure to an action, evaluate these actions from left to right, and collect the results. For a version that ignores the results see traverse_.

Examples

Expand

Basic usage:

In the first two examples we show each evaluated action mapping to the output structure.

>>> traverse Just [1,2,3,4]
Just [1,2,3,4]
>>> traverse id [Right 1, Right 2, Right 3, Right 4]
Right [1,2,3,4]

In the next examples, we show that Nothing and Left values short circuit the created structure.

>>> traverse (const Nothing) [1,2,3,4]
Nothing
>>> traverse (\x -> if odd x then Just x else Nothing)  [1,2,3,4]
Nothing
>>> traverse id [Right 1, Right 2, Right 3, Right 4, Left 0]
Left 0

sequenceA :: Applicative f => t (f a) -> f (t a) #

Evaluate each action in the structure from left to right, and collect the results. For a version that ignores the results see sequenceA_.

Examples

Expand

Basic usage:

For the first two examples we show sequenceA fully evaluating a a structure and collecting the results.

>>> sequenceA [Just 1, Just 2, Just 3]
Just [1,2,3]
>>> sequenceA [Right 1, Right 2, Right 3]
Right [1,2,3]

The next two example show Nothing and Just will short circuit the resulting structure if present in the input. For more context, check the Traversable instances for Either and Maybe.

>>> sequenceA [Just 1, Just 2, Just 3, Nothing]
Nothing
>>> sequenceA [Right 1, Right 2, Right 3, Left 4]
Left 4

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_.

Examples

Expand

mapM is literally a traverse with a type signature restricted to Monad. Its implementation may be more efficient due to additional power of Monad.

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_.

Examples

Expand

Basic usage:

The first two examples are instances where the input and and output of sequence are isomorphic.

>>> sequence $ Right [1,2,3,4]
[Right 1,Right 2,Right 3,Right 4]
>>> sequence $ [Right 1,Right 2,Right 3,Right 4]
Right [1,2,3,4]

The following examples demonstrate short circuit behavior for sequence.

>>> sequence $ Left [1,2,3,4]
Left [1,2,3,4]
>>> sequence $ [Left 0, Right 1,Right 2,Right 3,Right 4]
Left 0

Instances

Instances details
Traversable ZipList

Since: base-4.9.0.0

Instance details

Defined in Data.Traversable

Methods

traverse :: Applicative f => (a -> f b) -> ZipList a -> f (ZipList b) #

sequenceA :: Applicative f => ZipList (f a) -> f (ZipList a) #

mapM :: Monad m => (a -> m b) -> ZipList a -> m (ZipList b) #

sequence :: Monad m => ZipList (m a) -> m (ZipList a) #

Traversable Identity

Since: base-4.9.0.0

Instance details

Defined in Data.Traversable

Methods

traverse :: Applicative f => (a -> f b) -> Identity a -> f (Identity b) #

sequenceA :: Applicative f => Identity (f a) -> f (Identity a) #

mapM :: Monad m => (a -> m b) -> Identity a -> m (Identity b) #

sequence :: Monad m => Identity (m a) -> m (Identity a) #

Traversable First

Since: base-4.8.0.0

Instance details

Defined in Data.Traversable

Methods

traverse :: Applicative f => (a -> f b) -> First a -> f (First b) #

sequenceA :: Applicative f => First (f a) -> f (First a) #

mapM :: Monad m => (a -> m b) -> First a -> m (First b) #

sequence :: Monad m => First (m a) -> m (First a) #

Traversable Last

Since: base-4.8.0.0

Instance details

Defined in Data.Traversable

Methods

traverse :: Applicative f => (a -> f b) -> Last a -> f (Last b) #

sequenceA :: Applicative f => Last (f a) -> f (Last a) #

mapM :: Monad m => (a -> m b) -> Last a -> m (Last b) #

sequence :: Monad m => Last (m a) -> m (Last a) #

Traversable Down

Since: base-4.12.0.0

Instance details

Defined in Data.Traversable

Methods

traverse :: Applicative f => (a -> f b) -> Down a -> f (Down b) #

sequenceA :: Applicative f => Down (f a) -> f (Down a) #

mapM :: Monad m => (a -> m b) -> Down a -> m (Down b) #

sequence :: Monad m => Down (m a) -> m (Down a) #

Traversable Dual

Since: base-4.8.0.0

Instance details

Defined in Data.Traversable

Methods

traverse :: Applicative f => (a -> f b) -> Dual a -> f (Dual b) #

sequenceA :: Applicative f => Dual (f a) -> f (Dual a) #

mapM :: Monad m => (a -> m b) -> Dual a -> m (Dual b) #

sequence :: Monad m => Dual (m a) -> m (Dual a) #

Traversable Product

Since: base-4.8.0.0

Instance details

Defined in Data.Traversable

Methods

traverse :: Applicative f => (a -> f b) -> Product a -> f (Product b) #

sequenceA :: Applicative f => Product (f a) -> f (Product a) #

mapM :: Monad m => (a -> m b) -> Product a -> m (Product b) #

sequence :: Monad m => Product (m a) -> m (Product a) #

Traversable Sum

Since: base-4.8.0.0

Instance details

Defined in Data.Traversable

Methods

traverse :: Applicative f => (a -> f b) -> Sum a -> f (Sum b) #

sequenceA :: Applicative f => Sum (f a) -> f (Sum a) #

mapM :: Monad m => (a -> m b) -> Sum a -> m (Sum b) #

sequence :: Monad m => Sum (m a) -> m (Sum a) #

Traversable Par1

Since: base-4.9.0.0

Instance details

Defined in Data.Traversable

Methods

traverse :: Applicative f => (a -> f b) -> Par1 a -> f (Par1 b) #

sequenceA :: Applicative f => Par1 (f a) -> f (Par1 a) #

mapM :: Monad m => (a -> m b) -> Par1 a -> m (Par1 b) #

sequence :: Monad m => Par1 (m a) -> m (Par1 a) #

Traversable IntMap

Traverses in order of increasing key.

Instance details

Defined in Data.IntMap.Internal

Methods

traverse :: Applicative f => (a -> f b) -> IntMap a -> f (IntMap b) #

sequenceA :: Applicative f => IntMap (f a) -> f (IntMap a) #

mapM :: Monad m => (a -> m b) -> IntMap a -> m (IntMap b) #

sequence :: Monad m => IntMap (m a) -> m (IntMap a) #

Traversable DList 
Instance details

Defined in Data.DList.Internal

Methods

traverse :: Applicative f => (a -> f b) -> DList a -> f (DList b) #

sequenceA :: Applicative f => DList (f a) -> f (DList a) #

mapM :: Monad m => (a -> m b) -> DList a -> m (DList b) #

sequence :: Monad m => DList (m a) -> m (DList a) #

Traversable NonEmpty

Since: base-4.9.0.0

Instance details

Defined in Data.Traversable

Methods

traverse :: Applicative f => (a -> f b) -> NonEmpty a -> f (NonEmpty b) #

sequenceA :: Applicative f => NonEmpty (f a) -> f (NonEmpty a) #

mapM :: Monad m => (a -> m b) -> NonEmpty a -> m (NonEmpty b) #

sequence :: Monad m => NonEmpty (m a) -> m (NonEmpty a) #

Traversable Maybe

Since: base-2.1

Instance details

Defined in Data.Traversable

Methods

traverse :: Applicative f => (a -> f b) -> Maybe a -> f (Maybe b) #

sequenceA :: Applicative f => Maybe (f a) -> f (Maybe a) #

mapM :: Monad m => (a -> m b) -> Maybe a -> m (Maybe b) #

sequence :: Monad m => Maybe (m a) -> m (Maybe a) #

Traversable Solo

Since: base-4.15

Instance details

Defined in Data.Traversable

Methods

traverse :: Applicative f => (a -> f b) -> Solo a -> f (Solo b) #

sequenceA :: Applicative f => Solo (f a) -> f (Solo a) #

mapM :: Monad m => (a -> m b) -> Solo a -> m (Solo b) #

sequence :: Monad m => Solo (m a) -> m (Solo a) #

Traversable []

Since: base-2.1

Instance details

Defined in Data.Traversable

Methods

traverse :: Applicative f => (a -> f b) -> [a] -> f [b] #

sequenceA :: Applicative f => [f a] -> f [a] #

mapM :: Monad m => (a -> m b) -> [a] -> m [b] #

sequence :: Monad m => [m a] -> m [a] #

Traversable (Either a)

Since: base-4.7.0.0

Instance details

Defined in Data.Traversable

Methods

traverse :: Applicative f => (a0 -> f b) -> Either a a0 -> f (Either a b) #

sequenceA :: Applicative f => Either a (f a0) -> f (Either a a0) #

mapM :: Monad m => (a0 -> m b) -> Either a a0 -> m (Either a b) #

sequence :: Monad m => Either a (m a0) -> m (Either a a0) #

Traversable (Proxy :: Type -> Type)

Since: base-4.7.0.0

Instance details

Defined in Data.Traversable

Methods

traverse :: Applicative f => (a -> f b) -> Proxy a -> f (Proxy b) #

sequenceA :: Applicative f => Proxy (f a) -> f (Proxy a) #

mapM :: Monad m => (a -> m b) -> Proxy a -> m (Proxy b) #

sequence :: Monad m => Proxy (m a) -> m (Proxy a) #

Ix i => Traversable (Array i)

Since: base-2.1

Instance details

Defined in Data.Traversable

Methods

traverse :: Applicative f => (a -> f b) -> Array i a -> f (Array i b) #

sequenceA :: Applicative f => Array i (f a) -> f (Array i a) #

mapM :: Monad m => (a -> m b) -> Array i a -> m (Array i b) #

sequence :: Monad m => Array i (m a) -> m (Array i a) #

Traversable (U1 :: Type -> Type)

Since: base-4.9.0.0

Instance details

Defined in Data.Traversable

Methods

traverse :: Applicative f => (a -> f b) -> U1 a -> f (U1 b) #

sequenceA :: Applicative f => U1 (f a) -> f (U1 a) #

mapM :: Monad m => (a -> m b) -> U1 a -> m (U1 b) #

sequence :: Monad m => U1 (m a) -> m (U1 a) #

Traversable (UAddr :: Type -> Type)

Since: base-4.9.0.0

Instance details

Defined in Data.Traversable

Methods

traverse :: Applicative f => (a -> f b) -> UAddr a -> f (UAddr b) #

sequenceA :: Applicative f => UAddr (f a) -> f (UAddr a) #

mapM :: Monad m => (a -> m b) -> UAddr a -> m (UAddr b) #

sequence :: Monad m => UAddr (m a) -> m (UAddr a) #

Traversable (UChar :: Type -> Type)

Since: base-4.9.0.0

Instance details

Defined in Data.Traversable

Methods

traverse :: Applicative f => (a -> f b) -> UChar a -> f (UChar b) #

sequenceA :: Applicative f => UChar (f a) -> f (UChar a) #

mapM :: Monad m => (a -> m b) -> UChar a -> m (UChar b) #

sequence :: Monad m => UChar (m a) -> m (UChar a) #

Traversable (UDouble :: Type -> Type)

Since: base-4.9.0.0

Instance details

Defined in Data.Traversable

Methods

traverse :: Applicative f => (a -> f b) -> UDouble a -> f (UDouble b) #

sequenceA :: Applicative f => UDouble (f a) -> f (UDouble a) #

mapM :: Monad m => (a -> m b) -> UDouble a -> m (UDouble b) #

sequence :: Monad m => UDouble (m a) -> m (UDouble a) #

Traversable (UFloat :: Type -> Type)

Since: base-4.9.0.0

Instance details

Defined in Data.Traversable

Methods

traverse :: Applicative f => (a -> f b) -> UFloat a -> f (UFloat b) #

sequenceA :: Applicative f => UFloat (f a) -> f (UFloat a) #

mapM :: Monad m => (a -> m b) -> UFloat a -> m (UFloat b) #

sequence :: Monad m => UFloat (m a) -> m (UFloat a) #

Traversable (UInt :: Type -> Type)

Since: base-4.9.0.0

Instance details

Defined in Data.Traversable

Methods

traverse :: Applicative f => (a -> f b) -> UInt a -> f (UInt b) #

sequenceA :: Applicative f => UInt (f a) -> f (UInt a) #

mapM :: Monad m => (a -> m b) -> UInt a -> m (UInt b) #

sequence :: Monad m => UInt (m a) -> m (UInt a) #

Traversable (UWord :: Type -> Type)

Since: base-4.9.0.0

Instance details

Defined in Data.Traversable

Methods

traverse :: Applicative f => (a -> f b) -> UWord a -> f (UWord b) #

sequenceA :: Applicative f => UWord (f a) -> f (UWord a) #

mapM :: Monad m => (a -> m b) -> UWord a -> m (UWord b) #

sequence :: Monad m => UWord (m a) -> m (UWord a) #

Traversable (V1 :: Type -> Type)

Since: base-4.9.0.0

Instance details

Defined in Data.Traversable

Methods

traverse :: Applicative f => (a -> f b) -> V1 a -> f (V1 b) #

sequenceA :: Applicative f => V1 (f a) -> f (V1 a) #

mapM :: Monad m => (a -> m b) -> V1 a -> m (V1 b) #

sequence :: Monad m => V1 (m a) -> m (V1 a) #

Traversable ((,) a)

Since: base-4.7.0.0

Instance details

Defined in Data.Traversable

Methods

traverse :: Applicative f => (a0 -> f b) -> (a, a0) -> f (a, b) #

sequenceA :: Applicative f => (a, f a0) -> f (a, a0) #

mapM :: Monad m => (a0 -> m b) -> (a, a0) -> m (a, b) #

sequence :: Monad m => (a, m a0) -> m (a, a0) #

Traversable (Const m :: Type -> Type)

Since: base-4.7.0.0

Instance details

Defined in Data.Traversable

Methods

traverse :: Applicative f => (a -> f b) -> Const m a -> f (Const m b) #

sequenceA :: Applicative f => Const m (f a) -> f (Const m a) #

mapM :: Monad m0 => (a -> m0 b) -> Const m a -> m0 (Const m b) #

sequence :: Monad m0 => Const m (m0 a) -> m0 (Const m a) #

Traversable f => Traversable (Ap f)

Since: base-4.12.0.0

Instance details

Defined in Data.Traversable

Methods

traverse :: Applicative f0 => (a -> f0 b) -> Ap f a -> f0 (Ap f b) #

sequenceA :: Applicative f0 => Ap f (f0 a) -> f0 (Ap f a) #

mapM :: Monad m => (a -> m b) -> Ap f a -> m (Ap f b) #

sequence :: Monad m => Ap f (m a) -> m (Ap f a) #

Traversable f => Traversable (Alt f)

Since: base-4.12.0.0

Instance details

Defined in Data.Traversable

Methods

traverse :: Applicative f0 => (a -> f0 b) -> Alt f a -> f0 (Alt f b) #

sequenceA :: Applicative f0 => Alt f (f0 a) -> f0 (Alt f a) #

mapM :: Monad m => (a -> m b) -> Alt f a -> m (Alt f b) #

sequence :: Monad m => Alt f (m a) -> m (Alt f a) #

Traversable f => Traversable (Rec1 f)

Since: base-4.9.0.0

Instance details

Defined in Data.Traversable

Methods

traverse :: Applicative f0 => (a -> f0 b) -> Rec1 f a -> f0 (Rec1 f b) #

sequenceA :: Applicative f0 => Rec1 f (f0 a) -> f0 (Rec1 f a) #

mapM :: Monad m => (a -> m b) -> Rec1 f a -> m (Rec1 f b) #

sequence :: Monad m => Rec1 f (m a) -> m (Rec1 f a) #

Traversable f => Traversable (ErrorT e f) 
Instance details

Defined in Control.Monad.Trans.Error

Methods

traverse :: Applicative f0 => (a -> f0 b) -> ErrorT e f a -> f0 (ErrorT e f b) #

sequenceA :: Applicative f0 => ErrorT e f (f0 a) -> f0 (ErrorT e f a) #

mapM :: Monad m => (a -> m b) -> ErrorT e f a -> m (ErrorT e f b) #

sequence :: Monad m => ErrorT e f (m a) -> m (ErrorT e f a) #

Traversable f => Traversable (WriterT w f) 
Instance details

Defined in Control.Monad.Trans.Writer.Lazy

Methods

traverse :: Applicative f0 => (a -> f0 b) -> WriterT w f a -> f0 (WriterT w f b) #

sequenceA :: Applicative f0 => WriterT w f (f0 a) -> f0 (WriterT w f a) #

mapM :: Monad m => (a -> m b) -> WriterT w f a -> m (WriterT w f b) #

sequence :: Monad m => WriterT w f (m a) -> m (WriterT w f a) #

(Traversable f, Traversable g) => Traversable (f :*: g)

Since: base-4.9.0.0

Instance details

Defined in Data.Traversable

Methods

traverse :: Applicative f0 => (a -> f0 b) -> (f :*: g) a -> f0 ((f :*: g) b) #

sequenceA :: Applicative f0 => (f :*: g) (f0 a) -> f0 ((f :*: g) a) #

mapM :: Monad m => (a -> m b) -> (f :*: g) a -> m ((f :*: g) b) #

sequence :: Monad m => (f :*: g) (m a) -> m ((f :*: g) a) #

(Traversable f, Traversable g) => Traversable (f :+: g)

Since: base-4.9.0.0

Instance details

Defined in Data.Traversable

Methods

traverse :: Applicative f0 => (a -> f0 b) -> (f :+: g) a -> f0 ((f :+: g) b) #

sequenceA :: Applicative f0 => (f :+: g) (f0 a) -> f0 ((f :+: g) a) #

mapM :: Monad m => (a -> m b) -> (f :+: g) a -> m ((f :+: g) b) #

sequence :: Monad m => (f :+: g) (m a) -> m ((f :+: g) a) #

Traversable (K1 i c :: Type -> Type)

Since: base-4.9.0.0

Instance details

Defined in Data.Traversable

Methods

traverse :: Applicative f => (a -> f b) -> K1 i c a -> f (K1 i c b) #

sequenceA :: Applicative f => K1 i c (f a) -> f (K1 i c a) #

mapM :: Monad m => (a -> m b) -> K1 i c a -> m (K1 i c b) #

sequence :: Monad m => K1 i c (m a) -> m (K1 i c a) #

(Traversable f, Traversable g) => Traversable (f :.: g)

Since: base-4.9.0.0

Instance details

Defined in Data.Traversable

Methods

traverse :: Applicative f0 => (a -> f0 b) -> (f :.: g) a -> f0 ((f :.: g) b) #

sequenceA :: Applicative f0 => (f :.: g) (f0 a) -> f0 ((f :.: g) a) #

mapM :: Monad m => (a -> m b) -> (f :.: g) a -> m ((f :.: g) b) #

sequence :: Monad m => (f :.: g) (m a) -> m ((f :.: g) a) #

Traversable f => Traversable (M1 i c f)

Since: base-4.9.0.0

Instance details

Defined in Data.Traversable

Methods

traverse :: Applicative f0 => (a -> f0 b) -> M1 i c f a -> f0 (M1 i c f b) #

sequenceA :: Applicative f0 => M1 i c f (f0 a) -> f0 (M1 i c f a) #

mapM :: Monad m => (a -> m b) -> M1 i c f a -> m (M1 i c f b) #

sequence :: Monad m => M1 i c f (m a) -> m (M1 i c f a) #

class Semigroup a where #

The class of semigroups (types with an associative binary operation).

Instances should satisfy the following:

Associativity
x <> (y <> z) = (x <> y) <> z

Since: base-4.9.0.0

Methods

(<>) :: a -> a -> a infixr 6 #

An associative operation.

>>> [1,2,3] <> [4,5,6]
[1,2,3,4,5,6]

Instances

Instances details
Semigroup All

Since: base-4.9.0.0

Instance details

Defined in Data.Semigroup.Internal

Methods

(<>) :: All -> All -> All #

sconcat :: NonEmpty All -> All #

stimes :: Integral b => b -> All -> All #

Semigroup Any

Since: base-4.9.0.0

Instance details

Defined in Data.Semigroup.Internal

Methods

(<>) :: Any -> Any -> Any #

sconcat :: NonEmpty Any -> Any #

stimes :: Integral b => b -> Any -> Any #

Semigroup IntSet

Since: containers-0.5.7

Instance details

Defined in Data.IntSet.Internal

Semigroup Ordering

Since: base-4.9.0.0

Instance details

Defined in GHC.Base

Semigroup Doc 
Instance details

Defined in Text.PrettyPrint.HughesPJ

Methods

(<>) :: Doc -> Doc -> Doc #

sconcat :: NonEmpty Doc -> Doc #

stimes :: Integral b => b -> Doc -> Doc #

Semigroup ()

Since: base-4.9.0.0

Instance details

Defined in GHC.Base

Methods

(<>) :: () -> () -> () #

sconcat :: NonEmpty () -> () #

stimes :: Integral b => b -> () -> () #

Bits a => Semigroup (And a)

Since: base-4.16

Instance details

Defined in Data.Bits

Methods

(<>) :: And a -> And a -> And a #

sconcat :: NonEmpty (And a) -> And a #

stimes :: Integral b => b -> And a -> And a #

FiniteBits a => Semigroup (Iff a)

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 Data.Bits

Methods

(<>) :: Iff a -> Iff a -> Iff a #

sconcat :: NonEmpty (Iff a) -> Iff a #

stimes :: Integral b => b -> Iff a -> Iff a #

Bits a => Semigroup (Ior a)

Since: base-4.16

Instance details

Defined in Data.Bits

Methods

(<>) :: Ior a -> Ior a -> Ior a #

sconcat :: NonEmpty (Ior a) -> Ior a #

stimes :: Integral b => b -> Ior a -> Ior a #

Bits a => Semigroup (Xor a)

Since: base-4.16

Instance details

Defined in Data.Bits

Methods

(<>) :: Xor a -> Xor a -> Xor a #

sconcat :: NonEmpty (Xor a) -> Xor a #

stimes :: Integral b => b -> Xor a -> Xor a #

Semigroup a => Semigroup (Identity a)

Since: base-4.9.0.0

Instance details

Defined in Data.Functor.Identity

Methods

(<>) :: Identity a -> Identity a -> Identity a #

sconcat :: NonEmpty (Identity a) -> Identity a #

stimes :: Integral b => b -> Identity a -> Identity a #

Semigroup (First a)

Since: base-4.9.0.0

Instance details

Defined in Data.Monoid

Methods

(<>) :: First a -> First a -> First a #

sconcat :: NonEmpty (First a) -> First a #

stimes :: Integral b => b -> First a -> First a #

Semigroup (Last a)

Since: base-4.9.0.0

Instance details

Defined in Data.Monoid

Methods

(<>) :: Last a -> Last a -> Last a #

sconcat :: NonEmpty (Last a) -> Last a #

stimes :: Integral b => b -> Last a -> Last a #

Semigroup a => Semigroup (Down a)

Since: base-4.11.0.0

Instance details

Defined in Data.Ord

Methods

(<>) :: Down a -> Down a -> Down a #

sconcat :: NonEmpty (Down a) -> Down a #

stimes :: Integral b => b -> Down a -> Down a #

Semigroup a => Semigroup (Dual a)

Since: base-4.9.0.0

Instance details

Defined in Data.Semigroup.Internal

Methods

(<>) :: Dual a -> Dual a -> Dual a #

sconcat :: NonEmpty (Dual a) -> Dual a #

stimes :: Integral b => b -> Dual a -> Dual a #

Semigroup (Endo a)

Since: base-4.9.0.0

Instance details

Defined in Data.Semigroup.Internal

Methods

(<>) :: Endo a -> Endo a -> Endo a #

sconcat :: NonEmpty (Endo a) -> Endo a #

stimes :: Integral b => b -> Endo a -> Endo a #

Num a => Semigroup (Product a)

Since: base-4.9.0.0

Instance details

Defined in Data.Semigroup.Internal

Methods

(<>) :: Product a -> Product a -> Product a #

sconcat :: NonEmpty (Product a) -> Product a #

stimes :: Integral b => b -> Product a -> Product a #

Num a => Semigroup (Sum a)

Since: base-4.9.0.0

Instance details

Defined in Data.Semigroup.Internal

Methods

(<>) :: Sum a -> Sum a -> Sum a #

sconcat :: NonEmpty (Sum a) -> Sum a #

stimes :: Integral b => b -> Sum a -> Sum a #

Semigroup p => Semigroup (Par1 p)

Since: base-4.12.0.0

Instance details

Defined in GHC.Generics

Methods

(<>) :: Par1 p -> Par1 p -> Par1 p #

sconcat :: NonEmpty (Par1 p) -> Par1 p #

stimes :: Integral b => b -> Par1 p -> Par1 p #

Semigroup (IntMap a)

Since: containers-0.5.7

Instance details

Defined in Data.IntMap.Internal

Methods

(<>) :: IntMap a -> IntMap a -> IntMap a #

sconcat :: NonEmpty (IntMap a) -> IntMap a #

stimes :: Integral b => b -> IntMap a -> IntMap a #

Semigroup (DList a) 
Instance details

Defined in Data.DList.Internal

Methods

(<>) :: DList a -> DList a -> DList a #

sconcat :: NonEmpty (DList a) -> DList a #

stimes :: Integral b => b -> DList a -> DList a #

Semigroup a => Semigroup (IO a)

Since: base-4.10.0.0

Instance details

Defined in GHC.Base

Methods

(<>) :: IO a -> IO a -> IO a #

sconcat :: NonEmpty (IO a) -> IO a #

stimes :: Integral b => b -> IO a -> IO a #

Semigroup (Doc a) 
Instance details

Defined in Text.PrettyPrint.Annotated.HughesPJ

Methods

(<>) :: Doc a -> Doc a -> Doc a #

sconcat :: NonEmpty (Doc a) -> Doc a #

stimes :: Integral b => b -> Doc a -> Doc a #

Semigroup (NonEmpty a)

Since: base-4.9.0.0

Instance details

Defined in GHC.Base

Methods

(<>) :: NonEmpty a -> NonEmpty a -> NonEmpty a #

sconcat :: NonEmpty (NonEmpty a) -> NonEmpty a #

stimes :: Integral b => b -> NonEmpty a -> NonEmpty a #

Semigroup a => Semigroup (Maybe a)

Since: base-4.9.0.0

Instance details

Defined in GHC.Base

Methods

(<>) :: Maybe a -> Maybe a -> Maybe a #

sconcat :: NonEmpty (Maybe a) -> Maybe a #

stimes :: Integral b => b -> Maybe a -> Maybe a #

Semigroup a => Semigroup (a)

Since: base-4.15

Instance details

Defined in GHC.Base

Methods

(<>) :: (a) -> (a) -> (a) #

sconcat :: NonEmpty (a) -> (a) #

stimes :: Integral b => b -> (a) -> (a) #

Semigroup [a]

Since: base-4.9.0.0

Instance details

Defined in GHC.Base

Methods

(<>) :: [a] -> [a] -> [a] #

sconcat :: NonEmpty [a] -> [a] #

stimes :: Integral b => b -> [a] -> [a] #

Semigroup (Either a b)

Since: base-4.9.0.0

Instance details

Defined in Data.Either

Methods

(<>) :: Either a b -> Either a b -> Either a b #

sconcat :: NonEmpty (Either a b) -> Either a b #

stimes :: Integral b0 => b0 -> Either a b -> Either a b #

Semigroup (Proxy s)

Since: base-4.9.0.0

Instance details

Defined in Data.Proxy

Methods

(<>) :: Proxy s -> Proxy s -> Proxy s #

sconcat :: NonEmpty (Proxy s) -> Proxy s #

stimes :: Integral b => b -> Proxy s -> Proxy s #

Semigroup (U1 p)

Since: base-4.12.0.0

Instance details

Defined in GHC.Generics

Methods

(<>) :: U1 p -> U1 p -> U1 p #

sconcat :: NonEmpty (U1 p) -> U1 p #

stimes :: Integral b => b -> U1 p -> U1 p #

Semigroup (V1 p)

Since: base-4.12.0.0

Instance details

Defined in GHC.Generics

Methods

(<>) :: V1 p -> V1 p -> V1 p #

sconcat :: NonEmpty (V1 p) -> V1 p #

stimes :: Integral b => b -> V1 p -> V1 p #

Semigroup b => Semigroup (a -> b)

Since: base-4.9.0.0

Instance details

Defined in GHC.Base

Methods

(<>) :: (a -> b) -> (a -> b) -> a -> b #

sconcat :: NonEmpty (a -> b) -> a -> b #

stimes :: Integral b0 => b0 -> (a -> b) -> a -> b #

(Semigroup a, Semigroup b) => Semigroup (a, b)

Since: base-4.9.0.0

Instance details

Defined in GHC.Base

Methods

(<>) :: (a, b) -> (a, b) -> (a, b) #

sconcat :: NonEmpty (a, b) -> (a, b) #

stimes :: Integral b0 => b0 -> (a, b) -> (a, b) #

(Applicative f, Semigroup a) => Semigroup (Ap f a)

Since: base-4.12.0.0

Instance details

Defined in Data.Monoid

Methods

(<>) :: Ap f a -> Ap f a -> Ap f a #

sconcat :: NonEmpty (Ap f a) -> Ap f a #

stimes :: Integral b => b -> Ap f a -> Ap f a #

Alternative f => Semigroup (Alt f a)

Since: base-4.9.0.0

Instance details

Defined in Data.Semigroup.Internal

Methods

(<>) :: Alt f a -> Alt f a -> Alt f a #

sconcat :: NonEmpty (Alt f a) -> Alt f a #

stimes :: Integral b => b -> Alt f a -> Alt f a #

Semigroup (f p) => Semigroup (Rec1 f p)

Since: base-4.12.0.0

Instance details

Defined in GHC.Generics

Methods

(<>) :: Rec1 f p -> Rec1 f p -> Rec1 f p #

sconcat :: NonEmpty (Rec1 f p) -> Rec1 f p #

stimes :: Integral b => b -> Rec1 f p -> Rec1 f p #

(Semigroup a, Semigroup b, Semigroup c) => Semigroup (a, b, c)

Since: base-4.9.0.0

Instance details

Defined in GHC.Base

Methods

(<>) :: (a, b, c) -> (a, b, c) -> (a, b, c) #

sconcat :: NonEmpty (a, b, c) -> (a, b, c) #

stimes :: Integral b0 => b0 -> (a, b, c) -> (a, b, c) #

(Semigroup (f p), Semigroup (g p)) => Semigroup ((f :*: g) p)

Since: base-4.12.0.0

Instance details

Defined in GHC.Generics

Methods

(<>) :: (f :*: g) p -> (f :*: g) p -> (f :*: g) p #

sconcat :: NonEmpty ((f :*: g) p) -> (f :*: g) p #

stimes :: Integral b => b -> (f :*: g) p -> (f :*: g) p #

Semigroup c => Semigroup (K1 i c p)

Since: base-4.12.0.0

Instance details

Defined in GHC.Generics

Methods

(<>) :: K1 i c p -> K1 i c p -> K1 i c p #

sconcat :: NonEmpty (K1 i c p) -> K1 i c p #

stimes :: Integral b => b -> K1 i c p -> K1 i c p #

(Semigroup a, Semigroup b, Semigroup c, Semigroup d) => Semigroup (a, b, c, d)

Since: base-4.9.0.0

Instance details

Defined in GHC.Base

Methods

(<>) :: (a, b, c, d) -> (a, b, c, d) -> (a, b, c, d) #

sconcat :: NonEmpty (a, b, c, d) -> (a, b, c, d) #

stimes :: Integral b0 => b0 -> (a, b, c, d) -> (a, b, c, d) #

Semigroup (f (g p)) => Semigroup ((f :.: g) p)

Since: base-4.12.0.0

Instance details

Defined in GHC.Generics

Methods

(<>) :: (f :.: g) p -> (f :.: g) p -> (f :.: g) p #

sconcat :: NonEmpty ((f :.: g) p) -> (f :.: g) p #

stimes :: Integral b => b -> (f :.: g) p -> (f :.: g) p #

Semigroup (f p) => Semigroup (M1 i c f p)

Since: base-4.12.0.0

Instance details

Defined in GHC.Generics

Methods

(<>) :: M1 i c f p -> M1 i c f p -> M1 i c f p #

sconcat :: NonEmpty (M1 i c f p) -> M1 i c f p #

stimes :: Integral b => b -> M1 i c f p -> M1 i c f p #

(Semigroup a, Semigroup b, Semigroup c, Semigroup d, Semigroup e) => Semigroup (a, b, c, d, e)

Since: base-4.9.0.0

Instance details

Defined in GHC.Base

Methods

(<>) :: (a, b, c, d, e) -> (a, b, c, d, e) -> (a, b, c, d, e) #

sconcat :: NonEmpty (a, b, c, d, e) -> (a, b, c, d, e) #

stimes :: Integral b0 => b0 -> (a, b, c, d, e) -> (a, b, c, d, e) #

class Semigroup a => Monoid a where #

The class of monoids (types with an associative binary operation that has an identity). Instances should satisfy the following:

Right identity
x <> mempty = x
Left identity
mempty <> x = x
Associativity
x <> (y <> z) = (x <> y) <> z (Semigroup law)
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.

Minimal complete definition

mempty

Methods

mempty :: a #

Identity of mappend

>>> "Hello world" <> mempty
"Hello world"

mappend :: a -> a -> a #

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 #

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

Since: base-2.1

Instance details

Defined in Data.Semigroup.Internal

Methods

mempty :: All #

mappend :: All -> All -> All #

mconcat :: [All] -> All #

Monoid Any

Since: base-2.1

Instance details

Defined in Data.Semigroup.Internal

Methods

mempty :: Any #

mappend :: Any -> Any -> Any #

mconcat :: [Any] -> Any #

Monoid IntSet 
Instance details

Defined in Data.IntSet.Internal

Monoid Ordering

Since: base-2.1

Instance details

Defined in GHC.Base

Monoid Doc 
Instance details

Defined in Text.PrettyPrint.HughesPJ

Methods

mempty :: Doc #

mappend :: Doc -> Doc -> Doc #

mconcat :: [Doc] -> Doc #

Monoid ()

Since: base-2.1

Instance details

Defined in GHC.Base

Methods

mempty :: () #

mappend :: () -> () -> () #

mconcat :: [()] -> () #

FiniteBits a => Monoid (And a)

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 Data.Bits

Methods

mempty :: And a #

mappend :: And a -> And a -> And a #

mconcat :: [And a] -> And a #

FiniteBits a => Monoid (Iff a)

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 Data.Bits

Methods

mempty :: Iff a #

mappend :: Iff a -> Iff a -> Iff a #

mconcat :: [Iff a] -> Iff a #

Bits a => Monoid (Ior a)

Since: base-4.16

Instance details

Defined in Data.Bits

Methods

mempty :: Ior a #

mappend :: Ior a -> Ior a -> Ior a #

mconcat :: [Ior a] -> Ior a #

Bits a => Monoid (Xor a)

Since: base-4.16

Instance details

Defined in Data.Bits

Methods

mempty :: Xor a #

mappend :: Xor a -> Xor a -> Xor a #

mconcat :: [Xor a] -> Xor a #

Monoid a => Monoid (Identity a)

Since: base-4.9.0.0

Instance details

Defined in Data.Functor.Identity

Methods

mempty :: Identity a #

mappend :: Identity a -> Identity a -> Identity a #

mconcat :: [Identity a] -> Identity a #

Monoid (First a)

Since: base-2.1

Instance details

Defined in Data.Monoid

Methods

mempty :: First a #

mappend :: First a -> First a -> First a #

mconcat :: [First a] -> First a #

Monoid (Last a)

Since: base-2.1

Instance details

Defined in Data.Monoid

Methods

mempty :: Last a #

mappend :: Last a -> Last a -> Last a #

mconcat :: [Last a] -> Last a #

Monoid a => Monoid (Down a)

Since: base-4.11.0.0

Instance details

Defined in Data.Ord

Methods

mempty :: Down a #

mappend :: Down a -> Down a -> Down a #

mconcat :: [Down a] -> Down a #

Monoid a => Monoid (Dual a)

Since: base-2.1

Instance details

Defined in Data.Semigroup.Internal

Methods

mempty :: Dual a #

mappend :: Dual a -> Dual a -> Dual a #

mconcat :: [Dual a] -> Dual a #

Monoid (Endo a)

Since: base-2.1

Instance details

Defined in Data.Semigroup.Internal

Methods

mempty :: Endo a #

mappend :: Endo a -> Endo a -> Endo a #

mconcat :: [Endo a] -> Endo a #

Num a => Monoid (Product a)

Since: base-2.1

Instance details

Defined in Data.Semigroup.Internal

Methods

mempty :: Product a #

mappend :: Product a -> Product a -> Product a #

mconcat :: [Product a] -> Product a #

Num a => Monoid (Sum a)

Since: base-2.1

Instance details

Defined in Data.Semigroup.Internal

Methods

mempty :: Sum a #

mappend :: Sum a -> Sum a -> Sum a #

mconcat :: [Sum a] -> Sum a #

Monoid p => Monoid (Par1 p)

Since: base-4.12.0.0

Instance details

Defined in GHC.Generics

Methods

mempty :: Par1 p #

mappend :: Par1 p -> Par1 p -> Par1 p #

mconcat :: [Par1 p] -> Par1 p #

Monoid (IntMap a) 
Instance details

Defined in Data.IntMap.Internal

Methods

mempty :: IntMap a #

mappend :: IntMap a -> IntMap a -> IntMap a #

mconcat :: [IntMap a] -> IntMap a #

Monoid (DList a) 
Instance details

Defined in Data.DList.Internal

Methods

mempty :: DList a #

mappend :: DList a -> DList a -> DList a #

mconcat :: [DList a] -> DList a #

Monoid a => Monoid (IO a)

Since: base-4.9.0.0

Instance details

Defined in GHC.Base

Methods

mempty :: IO a #

mappend :: IO a -> IO a -> IO a #

mconcat :: [IO a] -> IO a #

Monoid (Doc a) 
Instance details

Defined in Text.PrettyPrint.Annotated.HughesPJ

Methods

mempty :: Doc a #

mappend :: Doc a -> Doc a -> Doc a #

mconcat :: [Doc a] -> Doc a #

Semigroup a => Monoid (Maybe a)

Lift a semigroup into Maybe forming a Monoid according to http://en.wikipedia.org/wiki/Monoid: "Any semigroup S may be turned into a monoid simply by adjoining an element e not in S and defining 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-2.1

Instance details

Defined in GHC.Base

Methods

mempty :: Maybe a #

mappend :: Maybe a -> Maybe a -> Maybe a #

mconcat :: [Maybe a] -> Maybe a #

Monoid a => Monoid (a)

Since: base-4.15

Instance details

Defined in GHC.Base

Methods

mempty :: (a) #

mappend :: (a) -> (a) -> (a) #

mconcat :: [(a)] -> (a) #

Monoid [a]

Since: base-2.1

Instance details

Defined in GHC.Base

Methods

mempty :: [a] #

mappend :: [a] -> [a] -> [a] #

mconcat :: [[a]] -> [a] #

Monoid (Proxy s)

Since: base-4.7.0.0

Instance details

Defined in Data.Proxy

Methods

mempty :: Proxy s #

mappend :: Proxy s -> Proxy s -> Proxy s #

mconcat :: [Proxy s] -> Proxy s #

Monoid (U1 p)

Since: base-4.12.0.0

Instance details

Defined in GHC.Generics

Methods

mempty :: U1 p #

mappend :: U1 p -> U1 p -> U1 p #

mconcat :: [U1 p] -> U1 p #

Monoid b => Monoid (a -> b)

Since: base-2.1

Instance details

Defined in GHC.Base

Methods

mempty :: a -> b #

mappend :: (a -> b) -> (a -> b) -> a -> b #

mconcat :: [a -> b] -> a -> b #

(Monoid a, Monoid b) => Monoid (a, b)

Since: base-2.1

Instance details

Defined in GHC.Base

Methods

mempty :: (a, b) #

mappend :: (a, b) -> (a, b) -> (a, b) #

mconcat :: [(a, b)] -> (a, b) #

(Applicative f, Monoid a) => Monoid (Ap f a)

Since: base-4.12.0.0

Instance details

Defined in Data.Monoid

Methods

mempty :: Ap f a #

mappend :: Ap f a -> Ap f a -> Ap f a #

mconcat :: [Ap f a] -> Ap f a #

Alternative f => Monoid (Alt f a)

Since: base-4.8.0.0

Instance details

Defined in Data.Semigroup.Internal

Methods

mempty :: Alt f a #

mappend :: Alt f a -> Alt f a -> Alt f a #

mconcat :: [Alt f a] -> Alt f a #

Monoid (f p) => Monoid (Rec1 f p)

Since: base-4.12.0.0

Instance details

Defined in GHC.Generics

Methods

mempty :: Rec1 f p #

mappend :: Rec1 f p -> Rec1 f p -> Rec1 f p #

mconcat :: [Rec1 f p] -> Rec1 f p #

(Monoid a, Monoid b, Monoid c) => Monoid (a, b, c)

Since: base-2.1

Instance details

Defined in GHC.Base

Methods

mempty :: (a, b, c) #

mappend :: (a, b, c) -> (a, b, c) -> (a, b, c) #

mconcat :: [(a, b, c)] -> (a, b, c) #

(Monoid (f p), Monoid (g p)) => Monoid ((f :*: g) p)

Since: base-4.12.0.0

Instance details

Defined in GHC.Generics

Methods

mempty :: (f :*: g) p #

mappend :: (f :*: g) p -> (f :*: g) p -> (f :*: g) p #

mconcat :: [(f :*: g) p] -> (f :*: g) p #

Monoid c => Monoid (K1 i c p)

Since: base-4.12.0.0

Instance details

Defined in GHC.Generics

Methods

mempty :: K1 i c p #

mappend :: K1 i c p -> K1 i c p -> K1 i c p #

mconcat :: [K1 i c p] -> K1 i c p #

(Monoid a, Monoid b, Monoid c, Monoid d) => Monoid (a, b, c, d)

Since: base-2.1

Instance details

Defined in GHC.Base

Methods

mempty :: (a, b, c, d) #

mappend :: (a, b, c, d) -> (a, b, c, d) -> (a, b, c, d) #

mconcat :: [(a, b, c, d)] -> (a, b, c, d) #

Monoid (f (g p)) => Monoid ((f :.: g) p)

Since: base-4.12.0.0

Instance details

Defined in GHC.Generics

Methods

mempty :: (f :.: g) p #

mappend :: (f :.: g) p -> (f :.: g) p -> (f :.: g) p #

mconcat :: [(f :.: g) p] -> (f :.: g) p #

Monoid (f p) => Monoid (M1 i c f p)

Since: base-4.12.0.0

Instance details

Defined in GHC.Generics

Methods

mempty :: M1 i c f p #

mappend :: M1 i c f p -> M1 i c f p -> M1 i c f p #

mconcat :: [M1 i c f p] -> M1 i c f p #

(Monoid a, Monoid b, Monoid c, Monoid d, Monoid e) => Monoid (a, b, c, d, e)

Since: base-2.1

Instance details

Defined in GHC.Base

Methods

mempty :: (a, b, c, d, e) #

mappend :: (a, b, c, d, e) -> (a, b, c, d, e) -> (a, b, c, d, e) #

mconcat :: [(a, b, c, d, e)] -> (a, b, c, d, e) #

data Bool #

Constructors

False 
True 

Instances

Instances details
Bits Bool

Interpret Bool as 1-bit bit-field

Since: base-4.7.0.0

Instance details

Defined in GHC.Bits

FiniteBits Bool

Since: base-4.7.0.0

Instance details

Defined in GHC.Bits

Bounded Bool

Since: base-2.1

Instance details

Defined in GHC.Enum

Enum Bool

Since: base-2.1

Instance details

Defined in GHC.Enum

Methods

succ :: Bool -> Bool #

pred :: Bool -> Bool #

toEnum :: Int -> Bool #

fromEnum :: Bool -> Int #

enumFrom :: Bool -> [Bool] #

enumFromThen :: Bool -> Bool -> [Bool] #

enumFromTo :: Bool -> Bool -> [Bool] #

enumFromThenTo :: Bool -> Bool -> Bool -> [Bool] #

Generic Bool 
Instance details

Defined in GHC.Generics

Associated Types

type Rep Bool :: Type -> Type #

Methods

from :: Bool -> Rep Bool x #

to :: Rep Bool x -> Bool #

SingKind Bool

Since: base-4.9.0.0

Instance details

Defined in GHC.Generics

Associated Types

type DemoteRep Bool

Methods

fromSing :: forall (a :: Bool). Sing a -> DemoteRep Bool

Ix Bool

Since: base-2.1

Instance details

Defined in GHC.Ix

Methods

range :: (Bool, Bool) -> [Bool] #

index :: (Bool, Bool) -> Bool -> Int #

unsafeIndex :: (Bool, Bool) -> Bool -> Int #

inRange :: (Bool, Bool) -> Bool -> Bool #

rangeSize :: (Bool, Bool) -> Int #

unsafeRangeSize :: (Bool, Bool) -> Int #

Read Bool

Since: base-2.1

Instance details

Defined in GHC.Read

Show Bool

Since: base-2.1

Instance details

Defined in GHC.Show

Methods

showsPrec :: Int -> Bool -> ShowS #

show :: Bool -> String #

showList :: [Bool] -> ShowS #

Typed Bool 
Instance details

Defined in Copilot.Core.Type

Eq Bool 
Instance details

Defined in GHC.Classes

Methods

(==) :: Bool -> Bool -> Bool #

(/=) :: Bool -> Bool -> Bool #

Ord Bool 
Instance details

Defined in GHC.Classes

Methods

compare :: Bool -> Bool -> Ordering #

(<) :: Bool -> Bool -> Bool #

(<=) :: Bool -> Bool -> Bool #

(>) :: Bool -> Bool -> Bool #

(>=) :: Bool -> Bool -> Bool #

max :: Bool -> Bool -> Bool #

min :: Bool -> Bool -> Bool #

SingI 'False

Since: base-4.9.0.0

Instance details

Defined in GHC.Generics

Methods

sing :: Sing 'False

SingI 'True

Since: base-4.9.0.0

Instance details

Defined in GHC.Generics

Methods

sing :: Sing 'True

Cast Bool Int16 Source #

Cast a boolean stream to a stream of numbers, producing 1 if the value at a point in time is True, and 0 otherwise.

Instance details

Defined in Copilot.Language.Operators.Cast

Cast Bool Int32 Source #

Cast a boolean stream to a stream of numbers, producing 1 if the value at a point in time is True, and 0 otherwise.

Instance details

Defined in Copilot.Language.Operators.Cast

Cast Bool Int64 Source #

Cast a boolean stream to a stream of numbers, producing 1 if the value at a point in time is True, and 0 otherwise.

Instance details

Defined in Copilot.Language.Operators.Cast

Cast Bool Int8 Source #

Cast a boolean stream to a stream of numbers, producing 1 if the value at a point in time is True, and 0 otherwise.

Instance details

Defined in Copilot.Language.Operators.Cast

Cast Bool Word16 Source #

Cast a boolean stream to a stream of numbers, producing 1 if the value at a point in time is True, and 0 otherwise.

Instance details

Defined in Copilot.Language.Operators.Cast

Cast Bool Word32 Source #

Cast a boolean stream to a stream of numbers, producing 1 if the value at a point in time is True, and 0 otherwise.

Instance details

Defined in Copilot.Language.Operators.Cast

Cast Bool Word64 Source #

Cast a boolean stream to a stream of numbers, producing 1 if the value at a point in time is True, and 0 otherwise.

Instance details

Defined in Copilot.Language.Operators.Cast

Cast Bool Word8 Source #

Cast a boolean stream to a stream of numbers, producing 1 if the value at a point in time is True, and 0 otherwise.

Instance details

Defined in Copilot.Language.Operators.Cast

Cast Bool Bool Source #

Identity casting.

Instance details

Defined in Copilot.Language.Operators.Cast

type DemoteRep Bool 
Instance details

Defined in GHC.Generics

type DemoteRep Bool = Bool
type Rep Bool

Since: base-4.6.0.0

Instance details

Defined in GHC.Generics

type Rep Bool = D1 ('MetaData "Bool" "GHC.Types" "ghc-prim" 'False) (C1 ('MetaCons "False" 'PrefixI 'False) (U1 :: Type -> Type) :+: C1 ('MetaCons "True" 'PrefixI 'False) (U1 :: Type -> Type))
data Sing (a :: Bool) 
Instance details

Defined in GHC.Generics

data Sing (a :: Bool) where

type String = [Char] #

A String is a list of characters. String constants in Haskell are values of type String.

See Data.List for operations on lists.

data Char #

The character type Char is an enumeration whose values represent Unicode (or equivalently ISO/IEC 10646) code points (i.e. characters, see http://www.unicode.org/ for details). This set extends the ISO 8859-1 (Latin-1) character set (the first 256 characters), which is itself an extension of the ASCII character set (the first 128 characters). A character literal in Haskell has type Char.

To convert a Char to or from the corresponding Int value defined by Unicode, use toEnum and fromEnum from the Enum class respectively (or equivalently ord and chr).

Instances

Instances details
Bounded Char

Since: base-2.1

Instance details

Defined in GHC.Enum

Enum Char

Since: base-2.1

Instance details

Defined in GHC.Enum

Methods

succ :: Char -> Char #

pred :: Char -> Char #

toEnum :: Int -> Char #

fromEnum :: Char -> Int #

enumFrom :: Char -> [Char] #

enumFromThen :: Char -> Char -> [Char] #

enumFromTo :: Char -> Char -> [Char] #

enumFromThenTo :: Char -> Char -> Char -> [Char] #

Ix Char

Since: base-2.1

Instance details

Defined in GHC.Ix

Methods

range :: (Char, Char) -> [Char] #

index :: (Char, Char) -> Char -> Int #

unsafeIndex :: (Char, Char) -> Char -> Int #

inRange :: (Char, Char) -> Char -> Bool #

rangeSize :: (Char, Char) -> Int #

unsafeRangeSize :: (Char, Char) -> Int #

Read Char

Since: base-2.1

Instance details

Defined in GHC.Read

Show Char

Since: base-2.1

Instance details

Defined in GHC.Show

Methods

showsPrec :: Int -> Char -> ShowS #

show :: Char -> String #

showList :: [Char] -> ShowS #

Eq Char 
Instance details

Defined in GHC.Classes

Methods

(==) :: Char -> Char -> Bool #

(/=) :: Char -> Char -> Bool #

Ord Char 
Instance details

Defined in GHC.Classes

Methods

compare :: Char -> Char -> Ordering #

(<) :: Char -> Char -> Bool #

(<=) :: Char -> Char -> Bool #

(>) :: Char -> Char -> Bool #

(>=) :: Char -> Char -> Bool #

max :: Char -> Char -> Char #

min :: Char -> Char -> Char #

ErrorList Char 
Instance details

Defined in Control.Monad.Trans.Error

Methods

listMsg :: String -> [Char] #

Generic1 (URec Char :: k -> Type) 
Instance details

Defined in GHC.Generics

Associated Types

type Rep1 (URec Char) :: k -> Type #

Methods

from1 :: forall (a :: k0). URec Char a -> Rep1 (URec Char) a #

to1 :: forall (a :: k0). Rep1 (URec Char) a -> URec Char a #

Foldable (UChar :: TYPE LiftedRep -> Type)

Since: base-4.9.0.0

Instance details

Defined in Data.Foldable

Methods

fold :: Monoid m => UChar m -> m #

foldMap :: Monoid m => (a -> m) -> UChar a -> m #

foldMap' :: Monoid m => (a -> m) -> UChar a -> m #

foldr :: (a -> b -> b) -> b -> UChar a -> b #

foldr' :: (a -> b -> b) -> b -> UChar a -> b #

foldl :: (b -> a -> b) -> b -> UChar a -> b #

foldl' :: (b -> a -> b) -> b -> UChar a -> b #

foldr1 :: (a -> a -> a) -> UChar a -> a #

foldl1 :: (a -> a -> a) -> UChar a -> a #

toList :: UChar a -> [a] #

null :: UChar a -> Bool #

length :: UChar a -> Int #

elem :: Eq a => a -> UChar a -> Bool #

maximum :: Ord a => UChar a -> a #

minimum :: Ord a => UChar a -> a #

sum :: Num a => UChar a -> a #

product :: Num a => UChar a -> a #

Traversable (UChar :: Type -> Type)

Since: base-4.9.0.0

Instance details

Defined in Data.Traversable

Methods

traverse :: Applicative f => (a -> f b) -> UChar a -> f (UChar b) #

sequenceA :: Applicative f => UChar (f a) -> f (UChar a) #

mapM :: Monad m => (a -> m b) -> UChar a -> m (UChar b) #

sequence :: Monad m => UChar (m a) -> m (UChar a) #

Functor (URec Char :: TYPE LiftedRep -> Type)

Since: base-4.9.0.0

Instance details

Defined in GHC.Generics

Methods

fmap :: (a -> b) -> URec Char a -> URec Char b #

(<$) :: a -> URec Char b -> URec Char a #

Generic (URec Char p) 
Instance details

Defined in GHC.Generics

Associated Types

type Rep (URec Char p) :: Type -> Type #

Methods

from :: URec Char p -> Rep (URec Char p) x #

to :: Rep (URec Char p) x -> URec Char p #

Show (URec Char p)

Since: base-4.9.0.0

Instance details

Defined in GHC.Generics

Methods

showsPrec :: Int -> URec Char p -> ShowS #

show :: URec Char p -> String #

showList :: [URec Char p] -> ShowS #

Eq (URec Char p)

Since: base-4.9.0.0

Instance details

Defined in GHC.Generics

Methods

(==) :: URec Char p -> URec Char p -> Bool #

(/=) :: URec Char p -> URec Char p -> Bool #

Ord (URec Char p)

Since: base-4.9.0.0

Instance details

Defined in GHC.Generics

Methods

compare :: URec Char p -> URec Char p -> Ordering #

(<) :: URec Char p -> URec Char p -> Bool #

(<=) :: URec Char p -> URec Char p -> Bool #

(>) :: URec Char p -> URec Char p -> Bool #

(>=) :: URec Char p -> URec Char p -> Bool #

max :: URec Char p -> URec Char p -> URec Char p #

min :: URec Char p -> URec Char p -> URec Char p #

data URec Char (p :: k)

Used for marking occurrences of Char#

Since: base-4.9.0.0

Instance details

Defined in GHC.Generics

data URec Char (p :: k) = UChar {}
type Rep1 (URec Char :: k -> Type)

Since: base-4.9.0.0

Instance details

Defined in GHC.Generics

type Rep1 (URec Char :: k -> Type) = D1 ('MetaData "URec" "GHC.Generics" "base" 'False) (C1 ('MetaCons "UChar" 'PrefixI 'True) (S1 ('MetaSel ('Just "uChar#") 'NoSourceUnpackedness 'NoSourceStrictness 'DecidedLazy) (UChar :: k -> Type)))
type Rep (URec Char p)

Since: base-4.9.0.0

Instance details

Defined in GHC.Generics

type Rep (URec Char p) = D1 ('MetaData "URec" "GHC.Generics" "base" 'False) (C1 ('MetaCons "UChar" 'PrefixI 'True) (S1 ('MetaSel ('Just "uChar#") 'NoSourceUnpackedness 'NoSourceStrictness 'DecidedLazy) (UChar :: Type -> Type)))

data Double #

Double-precision floating point numbers. It is desirable that this type be at least equal in range and precision to the IEEE double-precision type.

Instances

Instances details
Floating Double

Since: base-2.1

Instance details

Defined in GHC.Float

RealFloat Double

Since: base-2.1

Instance details

Defined in GHC.Float

Read Double

Since: base-2.1

Instance details

Defined in GHC.Read

Typed Double 
Instance details

Defined in Copilot.Core.Type

Eq Double

Note that due to the presence of NaN, Double's Eq instance does not satisfy reflexivity.

>>> 0/0 == (0/0 :: Double)
False

Also note that Double's Eq instance does not satisfy substitutivity:

>>> 0 == (-0 :: Double)
True
>>> recip 0 == recip (-0 :: Double)
False
Instance details

Defined in GHC.Classes

Methods

(==) :: Double -> Double -> Bool #

(/=) :: Double -> Double -> Bool #

Ord Double

Note that due to the presence of NaN, Double's Ord instance does not satisfy reflexivity.

>>> 0/0 <= (0/0 :: Double)
False

Also note that, due to the same, Ord's operator interactions are not respected by Double's instance:

>>> (0/0 :: Double) > 1
False
>>> compare (0/0 :: Double) 1
GT
Instance details

Defined in GHC.Classes

UnsafeCast Int16 Double Source #

Unsafe signed integer promotion to floating point values.

Instance details

Defined in Copilot.Language.Operators.Cast

UnsafeCast Int32 Double Source #

Unsafe signed integer promotion to floating point values.

Instance details

Defined in Copilot.Language.Operators.Cast

UnsafeCast Int64 Double Source #

Unsafe signed integer promotion to floating point values.

Instance details

Defined in Copilot.Language.Operators.Cast

UnsafeCast Int8 Double Source #

Unsafe signed integer promotion to floating point values.

Instance details

Defined in Copilot.Language.Operators.Cast

UnsafeCast Word16 Double Source #

Unsafe unsigned integer promotion to floating point values.

Instance details

Defined in Copilot.Language.Operators.Cast

UnsafeCast Word32 Double Source #

Unsafe unsigned integer promotion to floating point values.

Instance details

Defined in Copilot.Language.Operators.Cast

UnsafeCast Word64 Double Source #

Unsafe unsigned integer promotion to floating point values.

Instance details

Defined in Copilot.Language.Operators.Cast

UnsafeCast Word8 Double Source #

Unsafe unsigned integer promotion to floating point values.

Instance details

Defined in Copilot.Language.Operators.Cast

Generic1 (URec Double :: k -> Type) 
Instance details

Defined in GHC.Generics

Associated Types

type Rep1 (URec Double) :: k -> Type #

Methods

from1 :: forall (a :: k0). URec Double a -> Rep1 (URec Double) a #

to1 :: forall (a :: k0). Rep1 (URec Double) a -> URec Double a #

Foldable (UDouble :: TYPE LiftedRep -> Type)

Since: base-4.9.0.0

Instance details

Defined in Data.Foldable

Methods

fold :: Monoid m => UDouble m -> m #

foldMap :: Monoid m => (a -> m) -> UDouble a -> m #

foldMap' :: Monoid m => (a -> m) -> UDouble a -> m #

foldr :: (a -> b -> b) -> b -> UDouble a -> b #

foldr' :: (a -> b -> b) -> b -> UDouble a -> b #

foldl :: (b -> a -> b) -> b -> UDouble a -> b #

foldl' :: (b -> a -> b) -> b -> UDouble a -> b #

foldr1 :: (a -> a -> a) -> UDouble a -> a #

foldl1 :: (a -> a -> a) -> UDouble a -> a #

toList :: UDouble a -> [a] #

null :: UDouble a -> Bool #

length :: UDouble a -> Int #

elem :: Eq a => a -> UDouble a -> Bool #

maximum :: Ord a => UDouble a -> a #

minimum :: Ord a => UDouble a -> a #

sum :: Num a => UDouble a -> a #

product :: Num a => UDouble a -> a #

Traversable (UDouble :: Type -> Type)

Since: base-4.9.0.0

Instance details

Defined in Data.Traversable

Methods

traverse :: Applicative f => (a -> f b) -> UDouble a -> f (UDouble b) #

sequenceA :: Applicative f => UDouble (f a) -> f (UDouble a) #

mapM :: Monad m => (a -> m b) -> UDouble a -> m (UDouble b) #

sequence :: Monad m => UDouble (m a) -> m (UDouble a) #

Functor (URec Double :: TYPE LiftedRep -> Type)

Since: base-4.9.0.0

Instance details

Defined in GHC.Generics

Methods

fmap :: (a -> b) -> URec Double a -> URec Double b #

(<$) :: a -> URec Double b -> URec Double a #

Generic (URec Double p) 
Instance details

Defined in GHC.Generics

Associated Types

type Rep (URec Double p) :: Type -> Type #

Methods

from :: URec Double p -> Rep (URec Double p) x #

to :: Rep (URec Double p) x -> URec Double p #

Show (URec Double p)

Since: base-4.9.0.0

Instance details

Defined in GHC.Generics

Methods

showsPrec :: Int -> URec Double p -> ShowS #

show :: URec Double p -> String #

showList :: [URec Double p] -> ShowS #

Eq (URec Double p)

Since: base-4.9.0.0

Instance details

Defined in GHC.Generics

Methods

(==) :: URec Double p -> URec Double p -> Bool #

(/=) :: URec Double p -> URec Double p -> Bool #

Ord (URec Double p)

Since: base-4.9.0.0

Instance details

Defined in GHC.Generics

Methods

compare :: URec Double p -> URec Double p -> Ordering #

(<) :: URec Double p -> URec Double p -> Bool #

(<=) :: URec Double p -> URec Double p -> Bool #

(>) :: URec Double p -> URec Double p -> Bool #

(>=) :: URec Double p -> URec Double p -> Bool #

max :: URec Double p -> URec Double p -> URec Double p #

min :: URec Double p -> URec Double p -> URec Double p #

data URec Double (p :: k)

Used for marking occurrences of Double#

Since: base-4.9.0.0

Instance details

Defined in GHC.Generics

data URec Double (p :: k) = UDouble {}
type Rep1 (URec Double :: k -> Type)

Since: base-4.9.0.0

Instance details

Defined in GHC.Generics

type Rep1 (URec Double :: k -> Type) = D1 ('MetaData "URec" "GHC.Generics" "base" 'False) (C1 ('MetaCons "UDouble" 'PrefixI 'True) (S1 ('MetaSel ('Just "uDouble#") 'NoSourceUnpackedness 'NoSourceStrictness 'DecidedLazy) (UDouble :: k -> Type)))
type Rep (URec Double p)

Since: base-4.9.0.0

Instance details

Defined in GHC.Generics

type Rep (URec Double p) = D1 ('MetaData "URec" "GHC.Generics" "base" 'False) (C1 ('MetaCons "UDouble" 'PrefixI 'True) (S1 ('MetaSel ('Just "uDouble#") 'NoSourceUnpackedness 'NoSourceStrictness 'DecidedLazy) (UDouble :: Type -> Type)))

data Float #

Single-precision floating point numbers. It is desirable that this type be at least equal in range and precision to the IEEE single-precision type.

Instances

Instances details
Floating Float

Since: base-2.1

Instance details

Defined in GHC.Float

RealFloat Float

Since: base-2.1

Instance details

Defined in GHC.Float

Read Float

Since: base-2.1

Instance details

Defined in GHC.Read

Typed Float 
Instance details

Defined in Copilot.Core.Type

Eq Float

Note that due to the presence of NaN, Float's Eq instance does not satisfy reflexivity.

>>> 0/0 == (0/0 :: Float)
False

Also note that Float's Eq instance does not satisfy extensionality:

>>> 0 == (-0 :: Float)
True
>>> recip 0 == recip (-0 :: Float)
False
Instance details

Defined in GHC.Classes

Methods

(==) :: Float -> Float -> Bool #

(/=) :: Float -> Float -> Bool #

Ord Float

Note that due to the presence of NaN, Float's Ord instance does not satisfy reflexivity.

>>> 0/0 <= (0/0 :: Float)
False

Also note that, due to the same, Ord's operator interactions are not respected by Float's instance:

>>> (0/0 :: Float) > 1
False
>>> compare (0/0 :: Float) 1
GT
Instance details

Defined in GHC.Classes

Methods

compare :: Float -> Float -> Ordering #

(<) :: Float -> Float -> Bool #

(<=) :: Float -> Float -> Bool #

(>) :: Float -> Float -> Bool #

(>=) :: Float -> Float -> Bool #

max :: Float -> Float -> Float #

min :: Float -> Float -> Float #

UnsafeCast Int16 Float Source #

Unsafe signed integer promotion to floating point values.

Instance details

Defined in Copilot.Language.Operators.Cast

UnsafeCast Int32 Float Source #

Unsafe signed integer promotion to floating point values.

Instance details

Defined in Copilot.Language.Operators.Cast

UnsafeCast Int64 Float Source #

Unsafe signed integer promotion to floating point values.

Instance details

Defined in Copilot.Language.Operators.Cast

UnsafeCast Int8 Float Source #

Unsafe signed integer promotion to floating point values.

Instance details

Defined in Copilot.Language.Operators.Cast

UnsafeCast Word16 Float Source #

Unsafe unsigned integer promotion to floating point values.

Instance details

Defined in Copilot.Language.Operators.Cast

UnsafeCast Word32 Float Source #

Unsafe unsigned integer promotion to floating point values.

Instance details

Defined in Copilot.Language.Operators.Cast

UnsafeCast Word64 Float Source #

Unsafe unsigned integer promotion to floating point values.

Instance details

Defined in Copilot.Language.Operators.Cast

UnsafeCast Word8 Float Source #

Unsafe unsigned integer promotion to floating point values.

Instance details

Defined in Copilot.Language.Operators.Cast

Generic1 (URec Float :: k -> Type) 
Instance details

Defined in GHC.Generics

Associated Types

type Rep1 (URec Float) :: k -> Type #

Methods

from1 :: forall (a :: k0). URec Float a -> Rep1 (URec Float) a #

to1 :: forall (a :: k0). Rep1 (URec Float) a -> URec Float a #

Foldable (UFloat :: TYPE LiftedRep -> Type)

Since: base-4.9.0.0

Instance details

Defined in Data.Foldable

Methods

fold :: Monoid m => UFloat m -> m #

foldMap :: Monoid m => (a -> m) -> UFloat a -> m #

foldMap' :: Monoid m => (a -> m) -> UFloat a -> m #

foldr :: (a -> b -> b) -> b -> UFloat a -> b #

foldr' :: (a -> b -> b) -> b -> UFloat a -> b #

foldl :: (b -> a -> b) -> b -> UFloat a -> b #

foldl' :: (b -> a -> b) -> b -> UFloat a -> b #

foldr1 :: (a -> a -> a) -> UFloat a -> a #

foldl1 :: (a -> a -> a) -> UFloat a -> a #

toList :: UFloat a -> [a] #

null :: UFloat a -> Bool #

length :: UFloat a -> Int #

elem :: Eq a => a -> UFloat a -> Bool #

maximum :: Ord a => UFloat a -> a #

minimum :: Ord a => UFloat a -> a #

sum :: Num a => UFloat a -> a #

product :: Num a => UFloat a -> a #

Traversable (UFloat :: Type -> Type)

Since: base-4.9.0.0

Instance details

Defined in Data.Traversable

Methods

traverse :: Applicative f => (a -> f b) -> UFloat a -> f (UFloat b) #

sequenceA :: Applicative f => UFloat (f a) -> f (UFloat a) #

mapM :: Monad m => (a -> m b) -> UFloat a -> m (UFloat b) #

sequence :: Monad m => UFloat (m a) -> m (UFloat a) #

Functor (URec Float :: TYPE LiftedRep -> Type)

Since: base-4.9.0.0

Instance details

Defined in GHC.Generics

Methods

fmap :: (a -> b) -> URec Float a -> URec Float b #

(<$) :: a -> URec Float b -> URec Float a #

Generic (URec Float p) 
Instance details

Defined in GHC.Generics

Associated Types

type Rep (URec Float p) :: Type -> Type #

Methods

from :: URec Float p -> Rep (URec Float p) x #

to :: Rep (URec Float p) x -> URec Float p #

Show (URec Float p) 
Instance details

Defined in GHC.Generics

Methods

showsPrec :: Int -> URec Float p -> ShowS #

show :: URec Float p -> String #

showList :: [URec Float p] -> ShowS #

Eq (URec Float p) 
Instance details

Defined in GHC.Generics

Methods

(==) :: URec Float p -> URec Float p -> Bool #

(/=) :: URec Float p -> URec Float p -> Bool #

Ord (URec Float p) 
Instance details

Defined in GHC.Generics

Methods

compare :: URec Float p -> URec Float p -> Ordering #

(<) :: URec Float p -> URec Float p -> Bool #

(<=) :: URec Float p -> URec Float p -> Bool #

(>) :: URec Float p -> URec Float p -> Bool #

(>=) :: URec Float p -> URec Float p -> Bool #

max :: URec Float p -> URec Float p -> URec Float p #

min :: URec Float p -> URec Float p -> URec Float p #

data URec Float (p :: k)

Used for marking occurrences of Float#

Since: base-4.9.0.0

Instance details

Defined in GHC.Generics

data URec Float (p :: k) = UFloat {}
type Rep1 (URec Float :: k -> Type)

Since: base-4.9.0.0

Instance details

Defined in GHC.Generics

type Rep1 (URec Float :: k -> Type) = D1 ('MetaData "URec" "GHC.Generics" "base" 'False) (C1 ('MetaCons "UFloat" 'PrefixI 'True) (S1 ('MetaSel ('Just "uFloat#") 'NoSourceUnpackedness 'NoSourceStrictness 'DecidedLazy) (UFloat :: k -> Type)))
type Rep (URec Float p) 
Instance details

Defined in GHC.Generics

type Rep (URec Float p) = D1 ('MetaData "URec" "GHC.Generics" "base" 'False) (C1 ('MetaCons "UFloat" 'PrefixI 'True) (S1 ('MetaSel ('Just "uFloat#") 'NoSourceUnpackedness 'NoSourceStrictness 'DecidedLazy) (UFloat :: Type -> Type)))

data Int #

A fixed-precision integer type with at least the range [-2^29 .. 2^29-1]. The exact range for a given implementation can be determined by using minBound and maxBound from the Bounded class.

Instances

Instances details
Bits Int

Since: base-2.1

Instance details

Defined in GHC.Bits

Methods

(.&.) :: Int -> Int -> Int #

(.|.) :: Int -> Int -> Int #

xor :: Int -> Int -> Int #

complement :: Int -> Int #

shift :: Int -> Int -> Int #

rotate :: Int -> Int -> Int #

zeroBits :: Int #

bit :: Int -> Int #

setBit :: Int -> Int -> Int #

clearBit :: Int -> Int -> Int #

complementBit :: Int -> Int -> Int #

testBit :: Int -> Int -> Bool #

bitSizeMaybe :: Int -> Maybe Int #

bitSize :: Int -> Int #

isSigned :: Int -> Bool #

shiftL :: Int -> Int -> Int #

unsafeShiftL :: Int -> Int -> Int #

shiftR :: Int -> Int -> Int #

unsafeShiftR :: Int -> Int -> Int #

rotateL :: Int -> Int -> Int #

rotateR :: Int -> Int -> Int #

popCount :: Int -> Int #

FiniteBits Int

Since: base-4.6.0.0

Instance details

Defined in GHC.Bits

Bounded Int

Since: base-2.1

Instance details

Defined in GHC.Enum

Methods

minBound :: Int #

maxBound :: Int #

Enum Int

Since: base-2.1

Instance details

Defined in GHC.Enum

Methods

succ :: Int -> Int #

pred :: Int -> Int #

toEnum :: Int -> Int #

fromEnum :: Int -> Int #

enumFrom :: Int -> [Int] #

enumFromThen :: Int -> Int -> [Int] #

enumFromTo :: Int -> Int -> [Int] #

enumFromThenTo :: Int -> Int -> Int -> [Int] #

Ix Int

Since: base-2.1

Instance details

Defined in GHC.Ix

Methods

range :: (Int, Int) -> [Int] #

index :: (Int, Int) -> Int -> Int #

unsafeIndex :: (Int, Int) -> Int -> Int #

inRange :: (Int, Int) -> Int -> Bool #

rangeSize :: (Int, Int) -> Int #

unsafeRangeSize :: (Int, Int) -> Int #

Num Int

Since: base-2.1

Instance details

Defined in GHC.Num

Methods

(+) :: Int -> Int -> Int #

(-) :: Int -> Int -> Int #

(*) :: Int -> Int -> Int #

negate :: Int -> Int #

abs :: Int -> Int #

signum :: Int -> Int #

fromInteger :: Integer -> Int #

Read Int

Since: base-2.1

Instance details

Defined in GHC.Read

Integral Int

Since: base-2.0.1

Instance details

Defined in GHC.Real

Methods

quot :: Int -> Int -> Int #

rem :: Int -> Int -> Int #

div :: Int -> Int -> Int #

mod :: Int -> Int -> Int #

quotRem :: Int -> Int -> (Int, Int) #

divMod :: Int -> Int -> (Int, Int) #

toInteger :: Int -> Integer #

Real Int

Since: base-2.0.1

Instance details

Defined in GHC.Real

Methods

toRational :: Int -> Rational #

Show Int

Since: base-2.1

Instance details

Defined in GHC.Show

Methods

showsPrec :: Int -> Int -> ShowS #

show :: Int -> String #

showList :: [Int] -> ShowS #

Eq Int 
Instance details

Defined in GHC.Classes

Methods

(==) :: Int -> Int -> Bool #

(/=) :: Int -> Int -> Bool #

Ord Int 
Instance details

Defined in GHC.Classes

Methods

compare :: Int -> Int -> Ordering #

(<) :: Int -> Int -> Bool #

(<=) :: Int -> Int -> Bool #

(>) :: Int -> Int -> Bool #

(>=) :: Int -> Int -> Bool #

max :: Int -> Int -> Int #

min :: Int -> Int -> Int #

Generic1 (URec Int :: k -> Type) 
Instance details

Defined in GHC.Generics

Associated Types

type Rep1 (URec Int) :: k -> Type #

Methods

from1 :: forall (a :: k0). URec Int a -> Rep1 (URec Int) a #

to1 :: forall (a :: k0). Rep1 (URec Int) a -> URec Int a #

Foldable (UInt :: TYPE LiftedRep -> Type)

Since: base-4.9.0.0

Instance details

Defined in Data.Foldable

Methods

fold :: Monoid m => UInt m -> m #

foldMap :: Monoid m => (a -> m) -> UInt a -> m #

foldMap' :: Monoid m => (a -> m) -> UInt a -> m #

foldr :: (a -> b -> b) -> b -> UInt a -> b #

foldr' :: (a -> b -> b) -> b -> UInt a -> b #

foldl :: (b -> a -> b) -> b -> UInt a -> b #

foldl' :: (b -> a -> b) -> b -> UInt a -> b #

foldr1 :: (a -> a -> a) -> UInt a -> a #

foldl1 :: (a -> a -> a) -> UInt a -> a #

toList :: UInt a -> [a] #

null :: UInt a -> Bool #

length :: UInt a -> Int #

elem :: Eq a => a -> UInt a -> Bool #

maximum :: Ord a => UInt a -> a #

minimum :: Ord a => UInt a -> a #

sum :: Num a => UInt a -> a #

product :: Num a => UInt a -> a #

Traversable (UInt :: Type -> Type)

Since: base-4.9.0.0

Instance details

Defined in Data.Traversable

Methods

traverse :: Applicative f => (a -> f b) -> UInt a -> f (UInt b) #

sequenceA :: Applicative f => UInt (f a) -> f (UInt a) #

mapM :: Monad m => (a -> m b) -> UInt a -> m (UInt b) #

sequence :: Monad m => UInt (m a) -> m (UInt a) #

Functor (URec Int :: TYPE LiftedRep -> Type)

Since: base-4.9.0.0

Instance details

Defined in GHC.Generics

Methods

fmap :: (a -> b) -> URec Int a -> URec Int b #

(<$) :: a -> URec Int b -> URec Int a #

Generic (URec Int p) 
Instance details

Defined in GHC.Generics

Associated Types

type Rep (URec Int p) :: Type -> Type #

Methods

from :: URec Int p -> Rep (URec Int p) x #

to :: Rep (URec Int p) x -> URec Int p #

Show (URec Int p)

Since: base-4.9.0.0

Instance details

Defined in GHC.Generics

Methods

showsPrec :: Int -> URec Int p -> ShowS #

show :: URec Int p -> String #

showList :: [URec Int p] -> ShowS #

Eq (URec Int p)

Since: base-4.9.0.0

Instance details

Defined in GHC.Generics

Methods

(==) :: URec Int p -> URec Int p -> Bool #

(/=) :: URec Int p -> URec Int p -> Bool #

Ord (URec Int p)

Since: base-4.9.0.0

Instance details

Defined in GHC.Generics

Methods

compare :: URec Int p -> URec Int p -> Ordering #

(<) :: URec Int p -> URec Int p -> Bool #

(<=) :: URec Int p -> URec Int p -> Bool #

(>) :: URec Int p -> URec Int p -> Bool #

(>=) :: URec Int p -> URec Int p -> Bool #

max :: URec Int p -> URec Int p -> URec Int p #

min :: URec Int p -> URec Int p -> URec Int p #

data URec Int (p :: k)

Used for marking occurrences of Int#

Since: base-4.9.0.0

Instance details

Defined in GHC.Generics

data URec Int (p :: k) = UInt {}
type Rep1 (URec Int :: k -> Type)

Since: base-4.9.0.0

Instance details

Defined in GHC.Generics

type Rep1 (URec Int :: k -> Type) = D1 ('MetaData "URec" "GHC.Generics" "base" 'False) (C1 ('MetaCons "UInt" 'PrefixI 'True) (S1 ('MetaSel ('Just "uInt#") 'NoSourceUnpackedness 'NoSourceStrictness 'DecidedLazy) (UInt :: k -> Type)))
type Rep (URec Int p)

Since: base-4.9.0.0

Instance details

Defined in GHC.Generics

type Rep (URec Int p) = D1 ('MetaData "URec" "GHC.Generics" "base" 'False) (C1 ('MetaCons "UInt" 'PrefixI 'True) (S1 ('MetaSel ('Just "uInt#") 'NoSourceUnpackedness 'NoSourceStrictness 'DecidedLazy) (UInt :: Type -> Type)))

data Integer #

Arbitrary precision integers. In contrast with fixed-size integral types such as Int, the Integer type represents the entire infinite range of integers.

Integers are stored in a kind of sign-magnitude form, hence do not expect two's complement form when using bit operations.

If the value is small (fit into an Int), IS constructor is used. Otherwise Integer and IN constructors are used to store a BigNat representing respectively the positive or the negative value magnitude.

Invariant: Integer and IN are used iff value doesn't fit in IS

Instances

Instances details
Bits Integer

Since: base-2.1

Instance details

Defined in GHC.Bits

Enum Integer

Since: base-2.1

Instance details

Defined in GHC.Enum

Ix Integer

Since: base-2.1

Instance details

Defined in GHC.Ix

Num Integer

Since: base-2.1

Instance details

Defined in GHC.Num

Read Integer

Since: base-2.1

Instance details

Defined in GHC.Read

Integral Integer

Since: base-2.0.1

Instance details

Defined in GHC.Real

Real Integer

Since: base-2.0.1

Instance details

Defined in GHC.Real

Show Integer

Since: base-2.1

Instance details

Defined in GHC.Show

Eq Integer 
Instance details

Defined in GHC.Num.Integer

Methods

(==) :: Integer -> Integer -> Bool #

(/=) :: Integer -> Integer -> Bool #

Ord Integer 
Instance details

Defined in GHC.Num.Integer

data Maybe a #

The Maybe type encapsulates an optional value. A value of type Maybe a either contains a value of type a (represented as Just a), or it is empty (represented as Nothing). Using Maybe is a good way to deal with errors or exceptional cases without resorting to drastic measures such as error.

The Maybe type is also a monad. It is a simple kind of error monad, where all errors are represented by Nothing. A richer error monad can be built using the Either type.

Constructors

Nothing 
Just a 

Instances

Instances details
MonadFail Maybe

Since: base-4.9.0.0

Instance details

Defined in Control.Monad.Fail

Methods

fail :: String -> Maybe a #

MonadFix Maybe

Since: base-2.1

Instance details

Defined in Control.Monad.Fix

Methods

mfix :: (a -> Maybe a) -> Maybe a #

Foldable Maybe

Since: base-2.1

Instance details

Defined in Data.Foldable

Methods

fold :: Monoid m => Maybe m -> m #

foldMap :: Monoid m => (a -> m) -> Maybe a -> m #

foldMap' :: Monoid m => (a -> m) -> Maybe a -> m #

foldr :: (a -> b -> b) -> b -> Maybe a -> b #

foldr' :: (a -> b -> b) -> b -> Maybe a -> b #

foldl :: (b -> a -> b) -> b -> Maybe a -> b #

foldl' :: (b -> a -> b) -> b -> Maybe a -> b #

foldr1 :: (a -> a -> a) -> Maybe a -> a #

foldl1 :: (a -> a -> a) -> Maybe a -> a #

toList :: Maybe a -> [a] #

null :: Maybe a -> Bool #

length :: Maybe a -> Int #

elem :: Eq a => a -> Maybe a -> Bool #

maximum :: Ord a => Maybe a -> a #

minimum :: Ord a => Maybe a -> a #

sum :: Num a => Maybe a -> a #

product :: Num a => Maybe a -> a #

Eq1 Maybe

Since: base-4.9.0.0

Instance details

Defined in Data.Functor.Classes

Methods

liftEq :: (a -> b -> Bool) -> Maybe a -> Maybe b -> Bool #

Ord1 Maybe

Since: base-4.9.0.0

Instance details

Defined in Data.Functor.Classes

Methods

liftCompare :: (a -> b -> Ordering) -> Maybe a -> Maybe b -> Ordering #

Read1 Maybe

Since: base-4.9.0.0

Instance details

Defined in Data.Functor.Classes

Methods

liftReadsPrec :: (Int -> ReadS a) -> ReadS [a] -> Int -> ReadS (Maybe a) #

liftReadList :: (Int -> ReadS a) -> ReadS [a] -> ReadS [Maybe a] #

liftReadPrec :: ReadPrec a -> ReadPrec [a] -> ReadPrec (Maybe a) #

liftReadListPrec :: ReadPrec a -> ReadPrec [a] -> ReadPrec [Maybe a] #

Show1 Maybe

Since: base-4.9.0.0

Instance details

Defined in Data.Functor.Classes

Methods

liftShowsPrec :: (Int -> a -> ShowS) -> ([a] -> ShowS) -> Int -> Maybe a -> ShowS #

liftShowList :: (Int -> a -> ShowS) -> ([a] -> ShowS) -> [Maybe a] -> ShowS #

Traversable Maybe

Since: base-2.1

Instance details

Defined in Data.Traversable

Methods

traverse :: Applicative f => (a -> f b) -> Maybe a -> f (Maybe b) #

sequenceA :: Applicative f => Maybe (f a) -> f (Maybe a) #

mapM :: Monad m => (a -> m b) -> Maybe a -> m (Maybe b) #

sequence :: Monad m => Maybe (m a) -> m (Maybe a) #

Alternative Maybe

Since: base-2.1

Instance details

Defined in GHC.Base

Methods

empty :: Maybe a #

(<|>) :: Maybe a -> Maybe a -> Maybe a #

some :: Maybe a -> Maybe [a] #

many :: Maybe a -> Maybe [a] #

Applicative Maybe

Since: base-2.1

Instance details

Defined in GHC.Base

Methods

pure :: a -> Maybe a #

(<*>) :: Maybe (a -> b) -> Maybe a -> Maybe b #

liftA2 :: (a -> b -> c) -> Maybe a -> Maybe b -> Maybe c #

(*>) :: Maybe a -> Maybe b -> Maybe b #

(<*) :: Maybe a -> Maybe b -> Maybe a #

Functor Maybe

Since: base-2.1

Instance details

Defined in GHC.Base

Methods

fmap :: (a -> b) -> Maybe a -> Maybe b #

(<$) :: a -> Maybe b -> Maybe a #

Monad Maybe

Since: base-2.1

Instance details

Defined in GHC.Base

Methods

(>>=) :: Maybe a -> (a -> Maybe b) -> Maybe b #

(>>) :: Maybe a -> Maybe b -> Maybe b #

return :: a -> Maybe a #

MonadPlus Maybe

Since: base-2.1

Instance details

Defined in GHC.Base

Methods

mzero :: Maybe a #

mplus :: Maybe a -> Maybe a -> Maybe a #

Generic1 Maybe 
Instance details

Defined in GHC.Generics

Associated Types

type Rep1 Maybe :: k -> Type #

Methods

from1 :: forall (a :: k). Maybe a -> Rep1 Maybe a #

to1 :: forall (a :: k). Rep1 Maybe a -> Maybe a #

Semigroup a => Monoid (Maybe a)

Lift a semigroup into Maybe forming a Monoid according to http://en.wikipedia.org/wiki/Monoid: "Any semigroup S may be turned into a monoid simply by adjoining an element e not in S and defining 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-2.1

Instance details

Defined in GHC.Base

Methods

mempty :: Maybe a #

mappend :: Maybe a -> Maybe a -> Maybe a #

mconcat :: [Maybe a] -> Maybe a #

Semigroup a => Semigroup (Maybe a)

Since: base-4.9.0.0

Instance details

Defined in GHC.Base

Methods

(<>) :: Maybe a -> Maybe a -> Maybe a #

sconcat :: NonEmpty (Maybe a) -> Maybe a #

stimes :: Integral b => b -> Maybe a -> Maybe a #

Generic (Maybe a) 
Instance details

Defined in GHC.Generics

Associated Types

type Rep (Maybe a) :: Type -> Type #

Methods

from :: Maybe a -> Rep (Maybe a) x #

to :: Rep (Maybe a) x -> Maybe a #

SingKind a => SingKind (Maybe a)

Since: base-4.9.0.0

Instance details

Defined in GHC.Generics

Associated Types

type DemoteRep (Maybe a)

Methods

fromSing :: forall (a0 :: Maybe a). Sing a0 -> DemoteRep (Maybe a)

Read a => Read (Maybe a)

Since: base-2.1

Instance details

Defined in GHC.Read

Show a => Show (Maybe a)

Since: base-2.1

Instance details

Defined in GHC.Show

Methods

showsPrec :: Int -> Maybe a -> ShowS #

show :: Maybe a -> String #

showList :: [Maybe a] -> ShowS #

Eq a => Eq (Maybe a)

Since: base-2.1

Instance details

Defined in GHC.Maybe

Methods

(==) :: Maybe a -> Maybe a -> Bool #

(/=) :: Maybe a -> Maybe a -> Bool #

Ord a => Ord (Maybe a)

Since: base-2.1

Instance details

Defined in GHC.Maybe

Methods

compare :: Maybe a -> Maybe a -> Ordering #

(<) :: Maybe a -> Maybe a -> Bool #

(<=) :: Maybe a -> Maybe a -> Bool #

(>) :: Maybe a -> Maybe a -> Bool #

(>=) :: Maybe a -> Maybe a -> Bool #

max :: Maybe a -> Maybe a -> Maybe a #

min :: Maybe a -> Maybe a -> Maybe a #

SingI ('Nothing :: Maybe a)

Since: base-4.9.0.0

Instance details

Defined in GHC.Generics

Methods

sing :: Sing 'Nothing

SingI a2 => SingI ('Just a2 :: Maybe a1)

Since: base-4.9.0.0

Instance details

Defined in GHC.Generics

Methods

sing :: Sing ('Just a2)

type Rep1 Maybe

Since: base-4.6.0.0

Instance details

Defined in GHC.Generics

type Rep1 Maybe = D1 ('MetaData "Maybe" "GHC.Maybe" "base" 'False) (C1 ('MetaCons "Nothing" 'PrefixI 'False) (U1 :: Type -> Type) :+: C1 ('MetaCons "Just" 'PrefixI 'False) (S1 ('MetaSel ('Nothing :: Maybe Symbol) 'NoSourceUnpackedness 'NoSourceStrictness 'DecidedLazy) Par1))
type DemoteRep (Maybe a) 
Instance details

Defined in GHC.Generics

type DemoteRep (Maybe a) = Maybe (DemoteRep a)
type Rep (Maybe a)

Since: base-4.6.0.0

Instance details

Defined in GHC.Generics

type Rep (Maybe a) = D1 ('MetaData "Maybe" "GHC.Maybe" "base" 'False) (C1 ('MetaCons "Nothing" 'PrefixI 'False) (U1 :: Type -> Type) :+: C1 ('MetaCons "Just" 'PrefixI 'False) (S1 ('MetaSel ('Nothing :: Maybe Symbol) 'NoSourceUnpackedness 'NoSourceStrictness 'DecidedLazy) (Rec0 a)))
data Sing (b :: Maybe a) 
Instance details

Defined in GHC.Generics

data Sing (b :: Maybe a) where

data Ordering #

Constructors

LT 
EQ 
GT 

Instances

Instances details
Monoid Ordering

Since: base-2.1

Instance details

Defined in GHC.Base

Semigroup Ordering

Since: base-4.9.0.0

Instance details

Defined in GHC.Base

Bounded Ordering

Since: base-2.1

Instance details

Defined in GHC.Enum

Enum Ordering

Since: base-2.1

Instance details

Defined in GHC.Enum

Generic Ordering 
Instance details

Defined in GHC.Generics

Associated Types

type Rep Ordering :: Type -> Type #

Methods

from :: Ordering -> Rep Ordering x #

to :: Rep Ordering x -> Ordering #

Ix Ordering

Since: base-2.1

Instance details

Defined in GHC.Ix

Read Ordering

Since: base-2.1

Instance details

Defined in GHC.Read

Show Ordering

Since: base-2.1

Instance details

Defined in GHC.Show

Eq Ordering 
Instance details

Defined in GHC.Classes

Ord Ordering 
Instance details

Defined in GHC.Classes

type Rep Ordering

Since: base-4.6.0.0

Instance details

Defined in GHC.Generics

type Rep Ordering = D1 ('MetaData "Ordering" "GHC.Types" "ghc-prim" 'False) (C1 ('MetaCons "LT" 'PrefixI 'False) (U1 :: Type -> Type) :+: (C1 ('MetaCons "EQ" 'PrefixI 'False) (U1 :: Type -> Type) :+: C1 ('MetaCons "GT" 'PrefixI 'False) (U1 :: Type -> Type)))

type Rational = Ratio Integer #

Arbitrary-precision rational numbers, represented as a ratio of two Integer values. A rational number may be constructed using the % operator.

data IO a #

A value of type IO a is a computation which, when performed, does some I/O before returning a value of type a.

There is really only one way to "perform" an I/O action: bind it to Main.main in your program. When your program is run, the I/O will be performed. It isn't possible to perform I/O from an arbitrary function, unless that function is itself in the IO monad and called at some point, directly or indirectly, from Main.main.

IO is a monad, so IO actions can be combined using either the do-notation or the >> and >>= operations from the Monad class.

Instances

Instances details
MonadFail IO

Since: base-4.9.0.0

Instance details

Defined in Control.Monad.Fail

Methods

fail :: String -> IO a #

MonadFix IO

Since: base-2.1

Instance details

Defined in Control.Monad.Fix

Methods

mfix :: (a -> IO a) -> IO a #

MonadIO IO

Since: base-4.9.0.0

Instance details

Defined in Control.Monad.IO.Class

Methods

liftIO :: IO a -> IO a #

Alternative IO

Since: base-4.9.0.0

Instance details

Defined in GHC.Base

Methods

empty :: IO a #

(<|>) :: IO a -> IO a -> IO a #

some :: IO a -> IO [a] #

many :: IO a -> IO [a] #

Applicative IO

Since: base-2.1

Instance details

Defined in GHC.Base

Methods

pure :: a -> IO a #

(<*>) :: IO (a -> b) -> IO a -> IO b #

liftA2 :: (a -> b -> c) -> IO a -> IO b -> IO c #

(*>) :: IO a -> IO b -> IO b #

(<*) :: IO a -> IO b -> IO a #

Functor IO

Since: base-2.1

Instance details

Defined in GHC.Base

Methods

fmap :: (a -> b) -> IO a -> IO b #

(<$) :: a -> IO b -> IO a #

Monad IO

Since: base-2.1

Instance details

Defined in GHC.Base

Methods

(>>=) :: IO a -> (a -> IO b) -> IO b #

(>>) :: IO a -> IO b -> IO b #

return :: a -> IO a #

MonadPlus IO

Since: base-4.9.0.0

Instance details

Defined in GHC.Base

Methods

mzero :: IO a #

mplus :: IO a -> IO a -> IO a #

Monoid a => Monoid (IO a)

Since: base-4.9.0.0

Instance details

Defined in GHC.Base

Methods

mempty :: IO a #

mappend :: IO a -> IO a -> IO a #

mconcat :: [IO a] -> IO a #

Semigroup a => Semigroup (IO a)

Since: base-4.10.0.0

Instance details

Defined in GHC.Base

Methods

(<>) :: IO a -> IO a -> IO a #

sconcat :: NonEmpty (IO a) -> IO a #

stimes :: Integral b => b -> IO a -> IO a #

data Word #

A Word is an unsigned integral type, with the same size as Int.

Instances

Instances details
Bits Word

Since: base-2.1

Instance details

Defined in GHC.Bits

FiniteBits Word

Since: base-4.6.0.0

Instance details

Defined in GHC.Bits

Bounded Word

Since: base-2.1

Instance details

Defined in GHC.Enum

Enum Word

Since: base-2.1

Instance details

Defined in GHC.Enum

Methods

succ :: Word -> Word #

pred :: Word -> Word #

toEnum :: Int -> Word #

fromEnum :: Word -> Int #

enumFrom :: Word -> [Word] #

enumFromThen :: Word -> Word -> [Word] #

enumFromTo :: Word -> Word -> [Word] #

enumFromThenTo :: Word -> Word -> Word -> [Word] #

Ix Word

Since: base-4.6.0.0

Instance details

Defined in GHC.Ix

Methods

range :: (Word, Word) -> [Word] #

index :: (Word, Word) -> Word -> Int #

unsafeIndex :: (Word, Word) -> Word -> Int #

inRange :: (Word, Word) -> Word -> Bool #

rangeSize :: (Word, Word) -> Int #

unsafeRangeSize :: (Word, Word) -> Int #

Num Word

Since: base-2.1

Instance details

Defined in GHC.Num

Methods

(+) :: Word -> Word -> Word #

(-) :: Word -> Word -> Word #

(*) :: Word -> Word -> Word #

negate :: Word -> Word #

abs :: Word -> Word #

signum :: Word -> Word #

fromInteger :: Integer -> Word #

Read Word

Since: base-4.5.0.0

Instance details

Defined in GHC.Read

Integral Word

Since: base-2.1

Instance details

Defined in GHC.Real

Methods

quot :: Word -> Word -> Word #

rem :: Word -> Word -> Word #

div :: Word -> Word -> Word #

mod :: Word -> Word -> Word #

quotRem :: Word -> Word -> (Word, Word) #

divMod :: Word -> Word -> (Word, Word) #

toInteger :: Word -> Integer #

Real Word

Since: base-2.1

Instance details

Defined in GHC.Real

Methods

toRational :: Word -> Rational #

Show Word

Since: base-2.1

Instance details

Defined in GHC.Show

Methods

showsPrec :: Int -> Word -> ShowS #

show :: Word -> String #

showList :: [Word] -> ShowS #

Eq Word 
Instance details

Defined in GHC.Classes

Methods

(==) :: Word -> Word -> Bool #

(/=) :: Word -> Word -> Bool #

Ord Word 
Instance details

Defined in GHC.Classes

Methods

compare :: Word -> Word -> Ordering #

(<) :: Word -> Word -> Bool #

(<=) :: Word -> Word -> Bool #

(>) :: Word -> Word -> Bool #

(>=) :: Word -> Word -> Bool #

max :: Word -> Word -> Word #

min :: Word -> Word -> Word #

Generic1 (URec Word :: k -> Type) 
Instance details

Defined in GHC.Generics

Associated Types

type Rep1 (URec Word) :: k -> Type #

Methods

from1 :: forall (a :: k0). URec Word a -> Rep1 (URec Word) a #

to1 :: forall (a :: k0). Rep1 (URec Word) a -> URec Word a #

Foldable (UWord :: TYPE LiftedRep -> Type)

Since: base-4.9.0.0

Instance details

Defined in Data.Foldable

Methods

fold :: Monoid m => UWord m -> m #

foldMap :: Monoid m => (a -> m) -> UWord a -> m #

foldMap' :: Monoid m => (a -> m) -> UWord a -> m #

foldr :: (a -> b -> b) -> b -> UWord a -> b #

foldr' :: (a -> b -> b) -> b -> UWord a -> b #

foldl :: (b -> a -> b) -> b -> UWord a -> b #

foldl' :: (b -> a -> b) -> b -> UWord a -> b #

foldr1 :: (a -> a -> a) -> UWord a -> a #

foldl1 :: (a -> a -> a) -> UWord a -> a #

toList :: UWord a -> [a] #

null :: UWord a -> Bool #

length :: UWord a -> Int #

elem :: Eq a => a -> UWord a -> Bool #

maximum :: Ord a => UWord a -> a #

minimum :: Ord a => UWord a -> a #

sum :: Num a => UWord a -> a #

product :: Num a => UWord a -> a #

Traversable (UWord :: Type -> Type)

Since: base-4.9.0.0

Instance details

Defined in Data.Traversable

Methods

traverse :: Applicative f => (a -> f b) -> UWord a -> f (UWord b) #

sequenceA :: Applicative f => UWord (f a) -> f (UWord a) #

mapM :: Monad m => (a -> m b) -> UWord a -> m (UWord b) #

sequence :: Monad m => UWord (m a) -> m (UWord a) #

Functor (URec Word :: TYPE LiftedRep -> Type)

Since: base-4.9.0.0

Instance details

Defined in GHC.Generics

Methods

fmap :: (a -> b) -> URec Word a -> URec Word b #

(<$) :: a -> URec Word b -> URec Word a #

Generic (URec Word p) 
Instance details

Defined in GHC.Generics

Associated Types

type Rep (URec Word p) :: Type -> Type #

Methods

from :: URec Word p -> Rep (URec Word p) x #

to :: Rep (URec Word p) x -> URec Word p #

Show (URec Word p)

Since: base-4.9.0.0

Instance details

Defined in GHC.Generics

Methods

showsPrec :: Int -> URec Word p -> ShowS #

show :: URec Word p -> String #

showList :: [URec Word p] -> ShowS #

Eq (URec Word p)

Since: base-4.9.0.0

Instance details

Defined in GHC.Generics

Methods

(==) :: URec Word p -> URec Word p -> Bool #

(/=) :: URec Word p -> URec Word p -> Bool #

Ord (URec Word p)

Since: base-4.9.0.0

Instance details

Defined in GHC.Generics

Methods

compare :: URec Word p -> URec Word p -> Ordering #

(<) :: URec Word p -> URec Word p -> Bool #

(<=) :: URec Word p -> URec Word p -> Bool #

(>) :: URec Word p -> URec Word p -> Bool #

(>=) :: URec Word p -> URec Word p -> Bool #

max :: URec Word p -> URec Word p -> URec Word p #

min :: URec Word p -> URec Word p -> URec Word p #

data URec Word (p :: k)

Used for marking occurrences of Word#

Since: base-4.9.0.0

Instance details

Defined in GHC.Generics

data URec Word (p :: k) = UWord {}
type Rep1 (URec Word :: k -> Type)

Since: base-4.9.0.0

Instance details

Defined in GHC.Generics

type Rep1 (URec Word :: k -> Type) = D1 ('MetaData "URec" "GHC.Generics" "base" 'False) (C1 ('MetaCons "UWord" 'PrefixI 'True) (S1 ('MetaSel ('Just "uWord#") 'NoSourceUnpackedness 'NoSourceStrictness 'DecidedLazy) (UWord :: k -> Type)))
type Rep (URec Word p)

Since: base-4.9.0.0

Instance details

Defined in GHC.Generics

type Rep (URec Word p) = D1 ('MetaData "URec" "GHC.Generics" "base" 'False) (C1 ('MetaCons "UWord" 'PrefixI 'True) (S1 ('MetaSel ('Just "uWord#") 'NoSourceUnpackedness 'NoSourceStrictness 'DecidedLazy) (UWord :: Type -> Type)))

data Either a b #

The Either type represents values with two possibilities: a value of type Either a b is either Left a or Right b.

The Either type is sometimes used to represent a value which is either correct or an error; by convention, the Left constructor is used to hold an error value and the Right constructor is used to hold a correct value (mnemonic: "right" also means "correct").

Examples

Expand

The type Either String Int is the type of values which can be either a String or an Int. The Left constructor can be used only on Strings, and the Right constructor can be used only on Ints:

>>> let s = Left "foo" :: Either String Int
>>> s
Left "foo"
>>> let n = Right 3 :: Either String Int
>>> n
Right 3
>>> :type s
s :: Either String Int
>>> :type n
n :: Either String Int

The fmap from our Functor instance will ignore Left values, but will apply the supplied function to values contained in a Right:

>>> let s = Left "foo" :: Either String Int
>>> let n = Right 3 :: Either String Int
>>> fmap (*2) s
Left "foo"
>>> fmap (*2) n
Right 6

The Monad instance for Either allows us to chain together multiple actions which may fail, and fail overall if any of the individual steps failed. First we'll write a function that can either parse an Int from a Char, or fail.

>>> import Data.Char ( digitToInt, isDigit )
>>> :{
    let parseEither :: Char -> Either String Int
        parseEither c
          | isDigit c = Right (digitToInt c)
          | otherwise = Left "parse error"
>>> :}

The following should work, since both '1' and '2' can be parsed as Ints.

>>> :{
    let parseMultiple :: Either String Int
        parseMultiple = do
          x <- parseEither '1'
          y <- parseEither '2'
          return (x + y)
>>> :}
>>> parseMultiple
Right 3

But the following should fail overall, since the first operation where we attempt to parse 'm' as an Int will fail:

>>> :{
    let parseMultiple :: Either String Int
        parseMultiple = do
          x <- parseEither 'm'
          y <- parseEither '2'
          return (x + y)
>>> :}
>>> parseMultiple
Left "parse error"

Constructors

Left a 
Right b 

Instances

Instances details
Eq2 Either

Since: base-4.9.0.0

Instance details

Defined in Data.Functor.Classes

Methods

liftEq2 :: (a -> b -> Bool) -> (c -> d -> Bool) -> Either a c -> Either b d -> Bool #

Ord2 Either

Since: base-4.9.0.0

Instance details

Defined in Data.Functor.Classes

Methods

liftCompare2 :: (a -> b -> Ordering) -> (c -> d -> Ordering) -> Either a c -> Either b d -> Ordering #

Read2 Either

Since: base-4.9.0.0

Instance details

Defined in Data.Functor.Classes

Methods

liftReadsPrec2 :: (Int -> ReadS a) -> ReadS [a] -> (Int -> ReadS b) -> ReadS [b] -> Int -> ReadS (Either a b) #

liftReadList2 :: (Int -> ReadS a) -> ReadS [a] -> (Int -> ReadS b) -> ReadS [b] -> ReadS [Either a b] #

liftReadPrec2 :: ReadPrec a -> ReadPrec [a] -> ReadPrec b -> ReadPrec [b] -> ReadPrec (Either a b) #

liftReadListPrec2 :: ReadPrec a -> ReadPrec [a] -> ReadPrec b -> ReadPrec [b] -> ReadPrec [Either a b] #

Show2 Either

Since: base-4.9.0.0

Instance details

Defined in Data.Functor.Classes

Methods

liftShowsPrec2 :: (Int -> a -> ShowS) -> ([a] -> ShowS) -> (Int -> b -> ShowS) -> ([b] -> ShowS) -> Int -> Either a b -> ShowS #

liftShowList2 :: (Int -> a -> ShowS) -> ([a] -> ShowS) -> (Int -> b -> ShowS) -> ([b] -> ShowS) -> [Either a b] -> ShowS #

Generic1 (Either a :: Type -> Type) 
Instance details

Defined in GHC.Generics

Associated Types

type Rep1 (Either a) :: k -> Type #

Methods

from1 :: forall (a0 :: k). Either a a0 -> Rep1 (Either a) a0 #

to1 :: forall (a0 :: k). Rep1 (Either a) a0 -> Either a a0 #

MonadFix (Either e)

Since: base-4.3.0.0

Instance details

Defined in Control.Monad.Fix

Methods

mfix :: (a -> Either e a) -> Either e a #

Foldable (Either a)

Since: base-4.7.0.0

Instance details

Defined in Data.Foldable

Methods

fold :: Monoid m => Either a m -> m #

foldMap :: Monoid m => (a0 -> m) -> Either a a0 -> m #

foldMap' :: Monoid m => (a0 -> m) -> Either a a0 -> m #

foldr :: (a0 -> b -> b) -> b -> Either a a0 -> b #

foldr' :: (a0 -> b -> b) -> b -> Either a a0 -> b #

foldl :: (b -> a0 -> b) -> b -> Either a a0 -> b #

foldl' :: (b -> a0 -> b) -> b -> Either a a0 -> b #

foldr1 :: (a0 -> a0 -> a0) -> Either a a0 -> a0 #

foldl1 :: (a0 -> a0 -> a0) -> Either a a0 -> a0 #

toList :: Either a a0 -> [a0] #

null :: Either a a0 -> Bool #

length :: Either a a0 -> Int #

elem :: Eq a0 => a0 -> Either a a0 -> Bool #

maximum :: Ord a0 => Either a a0 -> a0 #

minimum :: Ord a0 => Either a a0 -> a0 #

sum :: Num a0 => Either a a0 -> a0 #

product :: Num a0 => Either a a0 -> a0 #

Eq a => Eq1 (Either a)

Since: base-4.9.0.0

Instance details

Defined in Data.Functor.Classes

Methods

liftEq :: (a0 -> b -> Bool) -> Either a a0 -> Either a b -> Bool #

Ord a => Ord1 (Either a)

Since: base-4.9.0.0

Instance details

Defined in Data.Functor.Classes

Methods

liftCompare :: (a0 -> b -> Ordering) -> Either a a0 -> Either a b -> Ordering #

Read a => Read1 (Either a)

Since: base-4.9.0.0

Instance details

Defined in Data.Functor.Classes

Methods

liftReadsPrec :: (Int -> ReadS a0) -> ReadS [a0] -> Int -> ReadS (Either a a0) #

liftReadList :: (Int -> ReadS a0) -> ReadS [a0] -> ReadS [Either a a0] #

liftReadPrec :: ReadPrec a0 -> ReadPrec [a0] -> ReadPrec (Either a a0) #

liftReadListPrec :: ReadPrec a0 -> ReadPrec [a0] -> ReadPrec [Either a a0] #

Show a => Show1 (Either a)

Since: base-4.9.0.0

Instance details

Defined in Data.Functor.Classes

Methods

liftShowsPrec :: (Int -> a0 -> ShowS) -> ([a0] -> ShowS) -> Int -> Either a a0 -> ShowS #

liftShowList :: (Int -> a0 -> ShowS) -> ([a0] -> ShowS) -> [Either a a0] -> ShowS #

Traversable (Either a)

Since: base-4.7.0.0

Instance details

Defined in Data.Traversable

Methods

traverse :: Applicative f => (a0 -> f b) -> Either a a0 -> f (Either a b) #

sequenceA :: Applicative f => Either a (f a0) -> f (Either a a0) #

mapM :: Monad m => (a0 -> m b) -> Either a a0 -> m (Either a b) #

sequence :: Monad m => Either a (m a0) -> m (Either a a0) #

Applicative (Either e)

Since: base-3.0

Instance details

Defined in Data.Either

Methods

pure :: a -> Either e a #

(<*>) :: Either e (a -> b) -> Either e a -> Either e b #

liftA2 :: (a -> b -> c) -> Either e a -> Either e b -> Either e c #

(*>) :: Either e a -> Either e b -> Either e b #

(<*) :: Either e a -> Either e b -> Either e a #

Functor (Either a)

Since: base-3.0

Instance details

Defined in Data.Either

Methods

fmap :: (a0 -> b) -> Either a a0 -> Either a b #

(<$) :: a0 -> Either a b -> Either a a0 #

Monad (Either e)

Since: base-4.4.0.0

Instance details

Defined in Data.Either

Methods

(>>=) :: Either e a -> (a -> Either e b) -> Either e b #

(>>) :: Either e a -> Either e b -> Either e b #

return :: a -> Either e a #

Semigroup (Either a b)

Since: base-4.9.0.0

Instance details

Defined in Data.Either

Methods

(<>) :: Either a b -> Either a b -> Either a b #

sconcat :: NonEmpty (Either a b) -> Either a b #

stimes :: Integral b0 => b0 -> Either a b -> Either a b #

Generic (Either a b) 
Instance details

Defined in GHC.Generics

Associated Types

type Rep (Either a b) :: Type -> Type #

Methods

from :: Either a b -> Rep (Either a b) x #

to :: Rep (Either a b) x -> Either a b #

(Read a, Read b) => Read (Either a b)

Since: base-3.0

Instance details

Defined in Data.Either

(Show a, Show b) => Show (Either a b)

Since: base-3.0

Instance details

Defined in Data.Either

Methods

showsPrec :: Int -> Either a b -> ShowS #

show :: Either a b -> String #

showList :: [Either a b] -> ShowS #

(Eq a, Eq b) => Eq (Either a b)

Since: base-2.1

Instance details

Defined in Data.Either

Methods

(==) :: Either a b -> Either a b -> Bool #

(/=) :: Either a b -> Either a b -> Bool #

(Ord a, Ord b) => Ord (Either a b)

Since: base-2.1

Instance details

Defined in Data.Either

Methods

compare :: Either a b -> Either a b -> Ordering #

(<) :: Either a b -> Either a b -> Bool #

(<=) :: Either a b -> Either a b -> Bool #

(>) :: Either a b -> Either a b -> Bool #

(>=) :: Either a b -> Either a b -> Bool #

max :: Either a b -> Either a b -> Either a b #

min :: Either a b -> Either a b -> Either a b #

type Rep1 (Either a :: Type -> Type)

Since: base-4.6.0.0

Instance details

Defined in GHC.Generics

type Rep (Either a b)

Since: base-4.6.0.0

Instance details

Defined in GHC.Generics

id :: a -> a #

Identity function.

id x = x

either :: (a -> c) -> (b -> c) -> Either a b -> c #

Case analysis for the Either type. If the value is Left a, apply the first function to a; if it is Right b, apply the second function to b.

Examples

Expand

We create two values of type Either String Int, one using the Left constructor and another using the Right constructor. Then we apply "either" the length function (if we have a String) or the "times-two" function (if we have an Int):

>>> let s = Left "foo" :: Either String Int
>>> let n = Right 3 :: Either String Int
>>> either length (*2) s
3
>>> either length (*2) n
6

mapM_ :: (Foldable t, Monad m) => (a -> m b) -> t a -> m () #

Map each element of a structure to a monadic action, evaluate these actions from left to right, and ignore the results. For a version that doesn't ignore the results see mapM.

mapM_ is just like traverse_, but specialised to monadic actions.

read :: Read a => String -> a #

The read function reads input from a string, which must be completely consumed by the input process. read fails with an error if the parse is unsuccessful, and it is therefore discouraged from being used in real applications. Use readMaybe or readEither for safe alternatives.

>>> read "123" :: Int
123
>>> read "hello" :: Int
*** Exception: Prelude.read: no parse

writeFile :: FilePath -> String -> IO () #

The computation writeFile file str function writes the string str, to the file file.

readLn :: Read a => IO a #

The readLn function combines getLine and readIO.

readIO :: Read a => String -> IO a #

The readIO function is similar to read except that it signals parse failure to the IO monad instead of terminating the program.

readFile :: FilePath -> IO String #

The readFile function reads a file and returns the contents of the file as a string. The file is read lazily, on demand, as with getContents.

putStrLn :: String -> IO () #

The same as putStr, but adds a newline character.

putStr :: String -> IO () #

Write a string to the standard output device (same as hPutStr stdout).

putChar :: Char -> IO () #

Write a character to the standard output device (same as hPutChar stdout).

interact :: (String -> String) -> IO () #

The interact function takes a function of type String->String as its argument. The entire input from the standard input device is passed to this function as its argument, and the resulting string is output on the standard output device.

getLine :: IO String #

Read a line from the standard input device (same as hGetLine stdin).

getContents :: IO String #

The getContents operation returns all user input as a single string, which is read lazily as it is needed (same as hGetContents stdin).

getChar :: IO Char #

Read a character from the standard input device (same as hGetChar stdin).

appendFile :: FilePath -> String -> IO () #

The computation appendFile file str function appends the string str, to the file file.

Note that writeFile and appendFile write a literal string to a file. To write a value of any printable type, as with print, use the show function to convert the value to a string first.

main = appendFile "squares" (show [(x,x*x) | x <- [0,0.1..2]])

ioError :: IOError -> IO a #

Raise an IOException in the IO monad.

type FilePath = String #

File and directory names are values of type String, whose precise meaning is operating system dependent. Files can be opened, yielding a handle which can then be used to operate on the contents of that file.

type IOError = IOException #

The Haskell 2010 type for exceptions in the IO monad. Any I/O operation may raise an IOException instead of returning a result. For a more general type of exception, including also those that arise in pure code, see Exception.

In Haskell 2010, this is an opaque type.

userError :: String -> IOError #

Construct an IOException value with a string describing the error. The fail method of the IO instance of the Monad class raises a userError, thus:

instance Monad IO where
  ...
  fail s = ioError (userError s)

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.

sequence_ is just like sequenceA_, but specialised to monadic actions.

or :: Foldable t => t Bool -> Bool #

or returns the disjunction of a container of Bools. For the result to be False, the container must be finite; True, however, results from a True value finitely far from the left end.

Examples

Expand

Basic usage:

>>> or []
False
>>> or [True]
True
>>> or [False]
False
>>> or [True, True, False]
True
>>> or (True : repeat False) -- Infinite list [True,False,False,False,...
True
>>> or (repeat False)
* Hangs forever *

notElem :: (Foldable t, Eq a) => a -> t a -> Bool infix 4 #

notElem is the negation of elem.

Examples

Expand

Basic usage:

>>> 3 `notElem` []
True
>>> 3 `notElem` [1,2]
True
>>> 3 `notElem` [1,2,3,4,5]
False

For infinite structures, notElem terminates if the value exists at a finite distance from the left side of the structure:

>>> 3 `notElem` [1..]
False
>>> 3 `notElem` ([4..] ++ [3])
* Hangs forever *

concatMap :: Foldable t => (a -> [b]) -> t a -> [b] #

Map a function over all the elements of a container and concatenate the resulting lists.

Examples

Expand

Basic usage:

>>> concatMap (take 3) [[1..], [10..], [100..], [1000..]]
[1,2,3,10,11,12,100,101,102,1000,1001,1002]
>>> concatMap (take 3) (Just [1..])
[1,2,3]

concat :: Foldable t => t [a] -> [a] #

The concatenation of all the elements of a container of lists.

Examples

Expand

Basic usage:

>>> concat (Just [1, 2, 3])
[1,2,3]
>>> concat (Left 42)
[]
>>> concat [[1, 2, 3], [4, 5], [6], []]
[1,2,3,4,5,6]

any :: Foldable t => (a -> Bool) -> t a -> Bool #

Determines whether any element of the structure satisfies the predicate.

Examples

Expand

Basic usage:

>>> any (> 3) []
False
>>> any (> 3) [1,2]
False
>>> any (> 3) [1,2,3,4,5]
True
>>> any (> 3) [1..]
True
>>> any (> 3) [0, -1..]
* Hangs forever *

and :: Foldable t => t Bool -> Bool #

and returns the conjunction of a container of Bools. For the result to be True, the container must be finite; False, however, results from a False value finitely far from the left end.

Examples

Expand

Basic usage:

>>> and []
True
>>> and [True]
True
>>> and [False]
False
>>> and [True, True, False]
False
>>> and (False : repeat True) -- Infinite list [False,True,True,True,...
False
>>> and (repeat True)
* Hangs forever *

all :: Foldable t => (a -> Bool) -> t a -> Bool #

Determines whether all elements of the structure satisfy the predicate.

Examples

Expand

Basic usage:

>>> all (> 3) []
True
>>> all (> 3) [1,2]
False
>>> all (> 3) [1,2,3,4,5]
False
>>> all (> 3) [1..]
False
>>> all (> 3) [4..]
* Hangs forever *

words :: String -> [String] #

words breaks a string up into a list of words, which were delimited by white space.

>>> words "Lorem ipsum\ndolor"
["Lorem","ipsum","dolor"]

unwords :: [String] -> String #

unwords is an inverse operation to words. It joins words with separating spaces.

>>> unwords ["Lorem", "ipsum", "dolor"]
"Lorem ipsum dolor"

unlines :: [String] -> String #

unlines is an inverse operation to lines. It joins lines, after appending a terminating newline to each.

>>> unlines ["Hello", "World", "!"]
"Hello\nWorld\n!\n"

lines :: String -> [String] #

lines breaks a string up into a list of strings at newline characters. The resulting strings do not contain newlines.

Note that after splitting the string at newline characters, the last part of the string is considered a line even if it doesn't end with a newline. For example,

>>> lines ""
[]
>>> lines "\n"
[""]
>>> lines "one"
["one"]
>>> lines "one\n"
["one"]
>>> lines "one\n\n"
["one",""]
>>> lines "one\ntwo"
["one","two"]
>>> lines "one\ntwo\n"
["one","two"]

Thus lines s contains at least as many elements as newlines in s.

reads :: Read a => ReadS a #

equivalent to readsPrec with a precedence of 0.

readParen :: Bool -> ReadS a -> ReadS a #

readParen True p parses what p parses, but surrounded with parentheses.

readParen False p parses what p parses, but optionally surrounded with parentheses.

lex :: ReadS String #

The lex function reads a single lexeme from the input, discarding initial white space, and returning the characters that constitute the lexeme. If the input string contains only white space, lex returns a single successful `lexeme' consisting of the empty string. (Thus lex "" = [("","")].) If there is no legal lexeme at the beginning of the input string, lex fails (i.e. returns []).

This lexer is not completely faithful to the Haskell lexical syntax in the following respects:

  • Qualified names are not handled properly
  • Octal and hexadecimal numerics are not recognized as a single token
  • Comments are not treated properly

type ReadS a = String -> [(a, String)] #

A parser for a type a, represented as a function that takes a String and returns a list of possible parses as (a,String) pairs.

Note that this kind of backtracking parser is very inefficient; reading a large structure may be quite slow (cf ReadP).

odd :: Integral a => a -> Bool #

lcm :: Integral a => a -> a -> a #

lcm x y is the smallest positive integer that both x and y divide.

gcd :: Integral a => a -> a -> a #

gcd x y is the non-negative factor of both x and y of which every common factor of x and y is also a factor; for example gcd 4 2 = 2, gcd (-4) 6 = 2, gcd 0 4 = 4. gcd 0 0 = 0. (That is, the common divisor that is "greatest" in the divisibility preordering.)

Note: Since for signed fixed-width integer types, abs minBound < 0, the result may be negative if one of the arguments is minBound (and necessarily is if the other is 0 or minBound) for such types.

even :: Integral a => a -> Bool #

(^^) :: (Fractional a, Integral b) => a -> b -> a infixr 8 #

raise a number to an integral power

type ShowS = String -> String #

The shows functions return a function that prepends the output String to an existing String. This allows constant-time concatenation of results using function composition.

shows :: Show a => a -> ShowS #

equivalent to showsPrec with a precedence of 0.

showString :: String -> ShowS #

utility function converting a String to a show function that simply prepends the string unchanged.

showParen :: Bool -> ShowS -> ShowS #

utility function that surrounds the inner show function with parentheses when the Bool parameter is True.

showChar :: Char -> ShowS #

utility function converting a Char to a show function that simply prepends the character unchanged.

zipWith3 :: (a -> b -> c -> d) -> [a] -> [b] -> [c] -> [d] #

The zipWith3 function takes a function which combines three elements, as well as three lists and returns a list of the function applied to corresponding elements, analogous to zipWith. It is capable of list fusion, but it is restricted to its first list argument and its resulting list.

zipWith3 (,,) xs ys zs == zip3 xs ys zs
zipWith3 f [x1,x2,x3..] [y1,y2,y3..] [z1,z2,z3..] == [f x1 y1 z1, f x2 y2 z2, f x3 y3 z3..]

zipWith :: (a -> b -> c) -> [a] -> [b] -> [c] #

\(\mathcal{O}(\min(m,n))\). zipWith generalises zip by zipping with the function given as the first argument, instead of a tupling function.

zipWith (,) xs ys == zip xs ys
zipWith f [x1,x2,x3..] [y1,y2,y3..] == [f x1 y1, f x2 y2, f x3 y3..]

For example, zipWith (+) is applied to two lists to produce the list of corresponding sums:

>>> zipWith (+) [1, 2, 3] [4, 5, 6]
[5,7,9]

zipWith is right-lazy:

>>> let f = undefined
>>> zipWith f [] undefined
[]

zipWith is capable of list fusion, but it is restricted to its first list argument and its resulting list.

zip3 :: [a] -> [b] -> [c] -> [(a, b, c)] #

zip3 takes three lists and returns a list of triples, analogous to zip. It is capable of list fusion, but it is restricted to its first list argument and its resulting list.

unzip3 :: [(a, b, c)] -> ([a], [b], [c]) #

The unzip3 function takes a list of triples and returns three lists, analogous to unzip.

>>> unzip3 []
([],[],[])
>>> unzip3 [(1, 'a', True), (2, 'b', False)]
([1,2],"ab",[True,False])

unzip :: [(a, b)] -> ([a], [b]) #

unzip transforms a list of pairs into a list of first components and a list of second components.

>>> unzip []
([],[])
>>> unzip [(1, 'a'), (2, 'b')]
([1,2],"ab")

takeWhile :: (a -> Bool) -> [a] -> [a] #

takeWhile, applied to a predicate p and a list xs, returns the longest prefix (possibly empty) of xs of elements that satisfy p.

>>> takeWhile (< 3) [1,2,3,4,1,2,3,4]
[1,2]
>>> takeWhile (< 9) [1,2,3]
[1,2,3]
>>> takeWhile (< 0) [1,2,3]
[]

tail :: [a] -> [a] #

\(\mathcal{O}(1)\). Extract the elements after the head of a list, which must be non-empty.

>>> tail [1, 2, 3]
[2,3]
>>> tail [1]
[]
>>> tail []
*** Exception: Prelude.tail: empty list

splitAt :: Int -> [a] -> ([a], [a]) #

splitAt n xs returns a tuple where first element is xs prefix of length n and second element is the remainder of the list:

>>> splitAt 6 "Hello World!"
("Hello ","World!")
>>> splitAt 3 [1,2,3,4,5]
([1,2,3],[4,5])
>>> splitAt 1 [1,2,3]
([1],[2,3])
>>> splitAt 3 [1,2,3]
([1,2,3],[])
>>> splitAt 4 [1,2,3]
([1,2,3],[])
>>> splitAt 0 [1,2,3]
([],[1,2,3])
>>> splitAt (-1) [1,2,3]
([],[1,2,3])

It is equivalent to (take n xs, drop n xs) when n is not _|_ (splitAt _|_ xs = _|_). splitAt is an instance of the more general genericSplitAt, in which n may be of any integral type.

span :: (a -> Bool) -> [a] -> ([a], [a]) #

span, applied to a predicate p and a list xs, returns a tuple where first element is longest prefix (possibly empty) of xs of elements that satisfy p and second element is the remainder of the list:

>>> span (< 3) [1,2,3,4,1,2,3,4]
([1,2],[3,4,1,2,3,4])
>>> span (< 9) [1,2,3]
([1,2,3],[])
>>> span (< 0) [1,2,3]
([],[1,2,3])

span p xs is equivalent to (takeWhile p xs, dropWhile p xs)

scanr1 :: (a -> a -> a) -> [a] -> [a] #

\(\mathcal{O}(n)\). scanr1 is a variant of scanr that has no starting value argument.

>>> scanr1 (+) [1..4]
[10,9,7,4]
>>> scanr1 (+) []
[]
>>> scanr1 (-) [1..4]
[-2,3,-1,4]
>>> scanr1 (&&) [True, False, True, True]
[False,False,True,True]
>>> scanr1 (||) [True, True, False, False]
[True,True,False,False]
>>> force $ scanr1 (+) [1..]
*** Exception: stack overflow

scanr :: (a -> b -> b) -> b -> [a] -> [b] #

\(\mathcal{O}(n)\). scanr is the right-to-left dual of scanl. Note that the order of parameters on the accumulating function are reversed compared to scanl. Also note that

head (scanr f z xs) == foldr f z xs.
>>> scanr (+) 0 [1..4]
[10,9,7,4,0]
>>> scanr (+) 42 []
[42]
>>> scanr (-) 100 [1..4]
[98,-97,99,-96,100]
>>> scanr (\nextChar reversedString -> nextChar : reversedString) "foo" ['a', 'b', 'c', 'd']
["abcdfoo","bcdfoo","cdfoo","dfoo","foo"]
>>> force $ scanr (+) 0 [1..]
*** Exception: stack overflow

scanl1 :: (a -> a -> a) -> [a] -> [a] #

\(\mathcal{O}(n)\). scanl1 is a variant of scanl that has no starting value argument:

scanl1 f [x1, x2, ...] == [x1, x1 `f` x2, ...]
>>> scanl1 (+) [1..4]
[1,3,6,10]
>>> scanl1 (+) []
[]
>>> scanl1 (-) [1..4]
[1,-1,-4,-8]
>>> scanl1 (&&) [True, False, True, True]
[True,False,False,False]
>>> scanl1 (||) [False, False, True, True]
[False,False,True,True]
>>> scanl1 (+) [1..]
* Hangs forever *

scanl :: (b -> a -> b) -> b -> [a] -> [b] #

\(\mathcal{O}(n)\). scanl is similar to foldl, but returns a list of successive reduced values from the left:

scanl f z [x1, x2, ...] == [z, z `f` x1, (z `f` x1) `f` x2, ...]

Note that

last (scanl f z xs) == foldl f z xs
>>> scanl (+) 0 [1..4]
[0,1,3,6,10]
>>> scanl (+) 42 []
[42]
>>> scanl (-) 100 [1..4]
[100,99,97,94,90]
>>> scanl (\reversedString nextChar -> nextChar : reversedString) "foo" ['a', 'b', 'c', 'd']
["foo","afoo","bafoo","cbafoo","dcbafoo"]
>>> scanl (+) 0 [1..]
* Hangs forever *

reverse :: [a] -> [a] #

reverse xs returns the elements of xs in reverse order. xs must be finite.

>>> reverse []
[]
>>> reverse [42]
[42]
>>> reverse [2,5,7]
[7,5,2]
>>> reverse [1..]
* Hangs forever *

replicate :: Int -> a -> [a] #

replicate n x is a list of length n with x the value of every element. It is an instance of the more general genericReplicate, in which n may be of any integral type.

>>> replicate 0 True
[]
>>> replicate (-1) True
[]
>>> replicate 4 True
[True,True,True,True]

repeat :: a -> [a] #

repeat x is an infinite list, with x the value of every element.

>>> take 20 $ repeat 17
[17,17,17,17,17,17,17,17,17...

lookup :: Eq a => a -> [(a, b)] -> Maybe b #

\(\mathcal{O}(n)\). lookup key assocs looks up a key in an association list.

>>> lookup 2 []
Nothing
>>> lookup 2 [(1, "first")]
Nothing
>>> lookup 2 [(1, "first"), (2, "second"), (3, "third")]
Just "second"

last :: [a] -> a #

\(\mathcal{O}(n)\). Extract the last element of a list, which must be finite and non-empty.

>>> last [1, 2, 3]
3
>>> last [1..]
* Hangs forever *
>>> last []
*** Exception: Prelude.last: empty list

iterate :: (a -> a) -> a -> [a] #

iterate f x returns an infinite list of repeated applications of f to x:

iterate f x == [x, f x, f (f x), ...]

Note that iterate is lazy, potentially leading to thunk build-up if the consumer doesn't force each iterate. See iterate' for a strict variant of this function.

>>> take 10 $ iterate not True
[True,False,True,False...
>>> take 10 $ iterate (+3) 42
[42,45,48,51,54,57,60,63...

init :: [a] -> [a] #

\(\mathcal{O}(n)\). Return all the elements of a list except the last one. The list must be non-empty.

>>> init [1, 2, 3]
[1,2]
>>> init [1]
[]
>>> init []
*** Exception: Prelude.init: empty list

head :: [a] -> a #

\(\mathcal{O}(1)\). Extract the first element of a list, which must be non-empty.

>>> head [1, 2, 3]
1
>>> head [1..]
1
>>> head []
*** Exception: Prelude.head: empty list

dropWhile :: (a -> Bool) -> [a] -> [a] #

dropWhile p xs returns the suffix remaining after takeWhile p xs.

>>> dropWhile (< 3) [1,2,3,4,5,1,2,3]
[3,4,5,1,2,3]
>>> dropWhile (< 9) [1,2,3]
[]
>>> dropWhile (< 0) [1,2,3]
[1,2,3]

break :: (a -> Bool) -> [a] -> ([a], [a]) #

break, applied to a predicate p and a list xs, returns a tuple where first element is longest prefix (possibly empty) of xs of elements that do not satisfy p and second element is the remainder of the list:

>>> break (> 3) [1,2,3,4,1,2,3,4]
([1,2,3],[4,1,2,3,4])
>>> break (< 9) [1,2,3]
([],[1,2,3])
>>> break (> 9) [1,2,3]
([1,2,3],[])

break p is equivalent to span (not . p).

maybe :: b -> (a -> b) -> Maybe a -> b #

The maybe function takes a default value, a function, and a Maybe value. If the Maybe value is Nothing, the function returns the default value. Otherwise, it applies the function to the value inside the Just and returns the result.

Examples

Expand

Basic usage:

>>> maybe False odd (Just 3)
True
>>> maybe False odd Nothing
False

Read an integer from a string using readMaybe. If we succeed, return twice the integer; that is, apply (*2) to it. If instead we fail to parse an integer, return 0 by default:

>>> import Text.Read ( readMaybe )
>>> maybe 0 (*2) (readMaybe "5")
10
>>> maybe 0 (*2) (readMaybe "")
0

Apply show to a Maybe Int. If we have Just n, we want to show the underlying Int n. But if we have Nothing, we return the empty string instead of (for example) "Nothing":

>>> maybe "" show (Just 5)
"5"
>>> maybe "" show Nothing
""

(<$>) :: Functor f => (a -> b) -> f a -> f b infixl 4 #

An infix synonym for fmap.

The name of this operator is an allusion to $. Note the similarities between their types:

 ($)  ::              (a -> b) ->   a ->   b
(<$>) :: Functor f => (a -> b) -> f a -> f b

Whereas $ is function application, <$> is function application lifted over a Functor.

Examples

Expand

Convert from a Maybe Int to a Maybe String using show:

>>> show <$> Nothing
Nothing
>>> show <$> Just 3
Just "3"

Convert from an Either Int Int to an Either Int String using show:

>>> show <$> Left 17
Left 17
>>> show <$> Right 17
Right "17"

Double each element of a list:

>>> (*2) <$> [1,2,3]
[2,4,6]

Apply even to the second element of a pair:

>>> even <$> (2,2)
(2,True)

uncurry :: (a -> b -> c) -> (a, b) -> c #

uncurry converts a curried function to a function on pairs.

Examples

Expand
>>> uncurry (+) (1,2)
3
>>> uncurry ($) (show, 1)
"1"
>>> map (uncurry max) [(1,2), (3,4), (6,8)]
[2,4,8]

curry :: ((a, b) -> c) -> a -> b -> c #

curry converts an uncurried function to a curried function.

Examples

Expand
>>> curry fst 1 2
1

subtract :: Num a => a -> a -> a #

the same as flip (-).

Because - is treated specially in the Haskell grammar, (- e) is not a section, but an application of prefix negation. However, (subtract exp) is equivalent to the disallowed section.

flip :: (a -> b -> c) -> b -> a -> c #

flip f takes its (first) two arguments in the reverse order of f.

>>> flip (++) "hello" "world"
"worldhello"

asTypeOf :: a -> a -> a #

asTypeOf is a type-restricted version of const. It is usually used as an infix operator, and its typing forces its first argument (which is usually overloaded) to have the same type as the second.

(=<<) :: Monad m => (a -> m b) -> m a -> m b infixr 1 #

Same as >>=, but with the arguments interchanged.

(.) :: (b -> c) -> (a -> b) -> a -> c infixr 9 #

Function composition.

($!) :: forall (r :: RuntimeRep) a (b :: TYPE r). (a -> b) -> a -> b infixr 0 #

Strict (call-by-value) application operator. It takes a function and an argument, evaluates the argument to weak head normal form (WHNF), then calls the function with that value.

undefined :: forall (r :: RuntimeRep) (a :: TYPE r). HasCallStack => a #

A special case of error. It is expected that compilers will recognize this and insert error messages which are more appropriate to the context in which undefined appears.

errorWithoutStackTrace :: forall (r :: RuntimeRep) (a :: TYPE r). [Char] -> a #

A variant of error that does not produce a stack trace.

Since: base-4.9.0.0

error :: forall (r :: RuntimeRep) (a :: TYPE r). HasCallStack => [Char] -> a #

error stops execution and displays an error message.