Copyright | © Herbert Valerio Riedel 2017-2018 |
---|---|
License | BSD-3-Clause |
Safe Haskell | Trustworthy |
Language | Haskell2010 |
This module is implicitly imported in all modules unless {-# LANGUAGE NoImplicitPrelude #-}
is in effect.
Synopsis
- data Char
- type String = [Char]
- class IsString a where
- data Bool
- (&&) :: Bool -> Bool -> Bool
- (||) :: Bool -> Bool -> Bool
- not :: Bool -> Bool
- otherwise :: Bool
- bool :: a -> a -> Bool -> a
- data Maybe a
- maybe :: b -> (a -> b) -> Maybe a -> b
- fromMaybe :: a -> Maybe a -> a
- isJust :: Maybe a -> Bool
- isNothing :: Maybe a -> Bool
- mapMaybe :: (a -> Maybe b) -> [a] -> [b]
- catMaybes :: [Maybe a] -> [a]
- listToMaybe :: [a] -> Maybe a
- maybeToList :: Maybe a -> [a]
- data Either a b
- either :: (a -> c) -> (b -> c) -> Either a b -> c
- fromLeft :: a -> Either a b -> a
- fromRight :: b -> Either a b -> b
- isLeft :: Either a b -> Bool
- isRight :: Either a b -> Bool
- lefts :: [Either a b] -> [a]
- rights :: [Either a b] -> [b]
- partitionEithers :: [Either a b] -> ([a], [b])
- data Ordering
- class Eq a where
- class Eq a => Ord a where
- comparing :: Ord a => (b -> a) -> b -> b -> Ordering
- class Enum a where
- class Bounded a where
- fst :: (a, b) -> a
- snd :: (a, b) -> b
- curry :: ((a, b) -> c) -> a -> b -> c
- uncurry :: (a -> b -> c) -> (a, b) -> c
- data Integer
- data Int
- data Int8
- data Int16
- data Int32
- data Int64
- data Word
- data Word8
- data Word16
- data Word32
- data Word64
- data Float
- data Double
- type Rational = Ratio Integer
- class Num a where
- class (Num a, Ord a) => Real a where
- class (Real a, Enum a) => Integral a where
- class Num a => Fractional a where
- class Fractional a => Floating a where
- class (Real a, Fractional a) => RealFrac a where
- class (RealFrac a, Floating a) => RealFloat a where
- subtract :: Num a => a -> a -> a
- even :: Integral a => a -> Bool
- odd :: Integral a => a -> Bool
- gcd :: Integral a => a -> a -> a
- lcm :: Integral a => a -> a -> a
- (^) :: (Num a, Integral b) => a -> b -> a
- (^^) :: (Fractional a, Integral b) => a -> b -> a
- fromIntegral :: (Integral a, Num b) => a -> b
- realToFrac :: (Real a, Fractional b) => a -> b
- class Semigroup a where
- sconcat :: Semigroup a => NonEmpty a -> a
- class Semigroup a => Monoid a where
- class Functor (f :: * -> *) where
- (<$>) :: Functor f => (a -> b) -> f a -> f b
- class Functor f => Applicative (f :: * -> *) where
- class Applicative m => Monad (m :: * -> *) where
- class Applicative f => Alternative (f :: * -> *) where
- class Monad m => MonadFail (m :: * -> *)
- class (Alternative m, Monad m) => MonadPlus (m :: * -> *) where
- guard :: Alternative f => Bool -> f ()
- ($>) :: Functor f => f a -> b -> f b
- forM :: (Traversable t, Monad m) => t a -> (a -> m b) -> m (t b)
- forM_ :: (Foldable t, Monad m) => t a -> (a -> m b) -> m ()
- mapM_ :: (Foldable t, Monad m) => (a -> m b) -> t a -> m ()
- sequence_ :: (Foldable t, Monad m) => t (m a) -> m ()
- (=<<) :: Monad m => (a -> m b) -> m a -> m b
- when :: Applicative f => Bool -> f () -> f ()
- unless :: Applicative f => Bool -> f () -> f ()
- void :: Functor f => f a -> f ()
- msum :: (Foldable t, MonadPlus m) => t (m a) -> m a
- replicateM :: Applicative m => Int -> m a -> m [a]
- replicateM_ :: Applicative m => Int -> m a -> m ()
- forever :: Applicative f => f a -> f b
- (>=>) :: Monad m => (a -> m b) -> (b -> m c) -> a -> m c
- (<=<) :: Monad m => (b -> m c) -> (a -> m b) -> a -> m c
- foldM :: (Foldable t, Monad m) => (b -> a -> m b) -> b -> t a -> m b
- foldM_ :: (Foldable t, Monad m) => (b -> a -> m b) -> b -> t a -> m ()
- join :: Monad m => m (m a) -> m a
- liftM :: Monad m => (a1 -> r) -> m a1 -> m r
- liftM2 :: Monad m => (a1 -> a2 -> r) -> m a1 -> m a2 -> m r
- liftM3 :: Monad m => (a1 -> a2 -> a3 -> r) -> m a1 -> m a2 -> m a3 -> m r
- liftM4 :: Monad m => (a1 -> a2 -> a3 -> a4 -> r) -> m a1 -> m a2 -> m a3 -> m a4 -> m r
- liftM5 :: Monad m => (a1 -> a2 -> a3 -> a4 -> a5 -> r) -> m a1 -> m a2 -> m a3 -> m a4 -> m a5 -> m r
- liftA :: Applicative f => (a -> b) -> f a -> f b
- liftA2 :: Applicative f => (a -> b -> c) -> f a -> f b -> f c
- liftA3 :: Applicative f => (a -> b -> c -> d) -> f a -> f b -> f c -> f d
- liftA4 :: Applicative f => (a -> b -> c -> d -> e) -> f a -> f b -> f c -> f d -> f e
- liftA5 :: Applicative f => (a -> b -> c -> d -> e -> g) -> f a -> f b -> f c -> f d -> f e -> f g
- class Foldable (t :: * -> *) where
- foldr' :: Foldable t => (a -> b -> b) -> b -> t a -> b
- foldl' :: Foldable t => (b -> a -> b) -> b -> t a -> b
- elem :: (Foldable t, Eq a) => a -> t a -> Bool
- product :: (Foldable t, Num a) => t a -> a
- sum :: (Foldable t, Num a) => t a -> a
- toList :: Foldable t => t a -> [a]
- find :: Foldable t => (a -> Bool) -> t a -> Maybe a
- class (Functor t, Foldable t) => Traversable (t :: * -> *) where
- and :: Foldable t => t Bool -> Bool
- or :: Foldable t => t Bool -> Bool
- any :: Foldable t => (a -> Bool) -> t a -> Bool
- all :: Foldable t => (a -> Bool) -> t a -> Bool
- concat :: Foldable t => t [a] -> [a]
- concatMap :: Foldable t => (a -> [b]) -> t a -> [b]
- asum :: (Foldable t, Alternative f) => t (f a) -> f a
- sequenceA_ :: (Foldable t, Applicative f) => t (f a) -> f ()
- traverse_ :: (Foldable t, Applicative f) => (a -> f b) -> t a -> f ()
- notElem :: (Foldable t, Eq a) => a -> t a -> Bool
- null :: Foldable t => t a -> Bool
- length :: Foldable t => t a -> Int
- class Typeable a => Data a
- class Typeable (a :: k)
- class Generic a
- head :: [a] -> Maybe a
- last :: [a] -> Maybe a
- init :: [a] -> Maybe [a]
- tail :: [a] -> Maybe [a]
- inits :: [a] -> [[a]]
- tails :: [a] -> [[a]]
- uncons :: [a] -> Maybe (a, [a])
- drop :: Int -> [a] -> [a]
- dropWhile :: (a -> Bool) -> [a] -> [a]
- take :: Int -> [a] -> [a]
- takeWhile :: (a -> Bool) -> [a] -> [a]
- break :: (a -> Bool) -> [a] -> ([a], [a])
- span :: (a -> Bool) -> [a] -> ([a], [a])
- splitAt :: Int -> [a] -> ([a], [a])
- filter :: (a -> Bool) -> [a] -> [a]
- iterate :: (a -> a) -> a -> [a]
- lookup :: Eq a => a -> [(a, b)] -> Maybe b
- partition :: (a -> Bool) -> [a] -> ([a], [a])
- repeat :: a -> [a]
- replicate :: Int -> a -> [a]
- reverse :: [a] -> [a]
- groupBy :: (a -> a -> Bool) -> [a] -> [[a]]
- intersperse :: a -> [a] -> [a]
- intercalate :: [a] -> [[a]] -> [a]
- scanl :: (b -> a -> b) -> b -> [a] -> [b]
- scanl1 :: (a -> a -> a) -> [a] -> [a]
- scanr :: (a -> b -> b) -> b -> [a] -> [b]
- scanr1 :: (a -> a -> a) -> [a] -> [a]
- zip :: [a] -> [b] -> [(a, b)]
- zip3 :: [a] -> [b] -> [c] -> [(a, b, c)]
- zip4 :: [a] -> [b] -> [c] -> [d] -> [(a, b, c, d)]
- zip5 :: [a] -> [b] -> [c] -> [d] -> [e] -> [(a, b, c, d, e)]
- zip6 :: [a] -> [b] -> [c] -> [d] -> [e] -> [f] -> [(a, b, c, d, e, f)]
- zip7 :: [a] -> [b] -> [c] -> [d] -> [e] -> [f] -> [g] -> [(a, b, c, d, e, f, g)]
- zipWith :: (a -> b -> c) -> [a] -> [b] -> [c]
- zipWith3 :: (a -> b -> c -> d) -> [a] -> [b] -> [c] -> [d]
- zipWith4 :: (a -> b -> c -> d -> e) -> [a] -> [b] -> [c] -> [d] -> [e]
- zipWith5 :: (a -> b -> c -> d -> e -> f) -> [a] -> [b] -> [c] -> [d] -> [e] -> [f]
- zipWith6 :: (a -> b -> c -> d -> e -> f -> g) -> [a] -> [b] -> [c] -> [d] -> [e] -> [f] -> [g]
- zipWith7 :: (a -> b -> c -> d -> e -> f -> g -> h) -> [a] -> [b] -> [c] -> [d] -> [e] -> [f] -> [g] -> [h]
- unzip :: [(a, b)] -> ([a], [b])
- unzip3 :: [(a, b, c)] -> ([a], [b], [c])
- unzip4 :: [(a, b, c, d)] -> ([a], [b], [c], [d])
- unzip5 :: [(a, b, c, d, e)] -> ([a], [b], [c], [d], [e])
- unzip6 :: [(a, b, c, d, e, f)] -> ([a], [b], [c], [d], [e], [f])
- unzip7 :: [(a, b, c, d, e, f, g)] -> ([a], [b], [c], [d], [e], [f], [g])
- data NonEmpty a = a :| [a]
- class Show a where
- type ShowS = String -> String
- shows :: Show a => a -> ShowS
- showChar :: Char -> ShowS
- showString :: String -> ShowS
- showParen :: Bool -> ShowS -> ShowS
- class Read a where
- type ReadS a = String -> [(a, String)]
- reads :: Read a => ReadS a
- readParen :: Bool -> ReadS a -> ReadS a
- read :: Read a => String -> Maybe a
- data IO a
- class Monad m => MonadIO (m :: * -> *) where
- putChar :: Char -> IO ()
- putStr :: String -> IO ()
- putStrLn :: String -> IO ()
- print :: Show a => a -> IO ()
- getChar :: IO Char
- getLine :: IO String
- getContents :: IO String
- type FilePath = String
- readFile :: FilePath -> IO String
- writeFile :: FilePath -> String -> IO ()
- appendFile :: FilePath -> String -> IO ()
- id :: a -> a
- const :: a -> b -> a
- (.) :: (b -> c) -> (a -> b) -> a -> c
- flip :: (a -> b -> c) -> b -> a -> c
- ($) :: (a -> b) -> a -> b
- ($!) :: (a -> b) -> a -> b
- (&) :: a -> (a -> b) -> b
- until :: (a -> Bool) -> (a -> a) -> a -> a
- asTypeOf :: a -> a -> a
- seq :: a -> b -> b
- on :: (b -> b -> c) -> (a -> b) -> a -> a -> c
- error :: HasCallStack => [Char] -> a
- errorWithoutStackTrace :: [Char] -> a
- undefined :: HasCallStack => a
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
Bounded Char | Since: base-2.1 |
Enum Char | Since: base-2.1 |
Eq Char | |
Data Char | Since: base-4.0.0.0 |
Defined in Data.Data gfoldl :: (forall d b. Data d => c (d -> b) -> d -> c b) -> (forall g. g -> c g) -> Char -> c Char # gunfold :: (forall b r. Data b => c (b -> r) -> c r) -> (forall r. r -> c r) -> Constr -> c Char # dataTypeOf :: Char -> DataType # dataCast1 :: Typeable t => (forall d. Data d => c (t d)) -> Maybe (c Char) # dataCast2 :: Typeable t => (forall d e. (Data d, Data e) => c (t d e)) -> Maybe (c Char) # gmapT :: (forall b. Data b => b -> b) -> Char -> Char # gmapQl :: (r -> r' -> r) -> r -> (forall d. Data d => d -> r') -> Char -> r # gmapQr :: (r' -> r -> r) -> r -> (forall d. Data d => d -> r') -> Char -> r # gmapQ :: (forall d. Data d => d -> u) -> Char -> [u] # gmapQi :: Int -> (forall d. Data d => d -> u) -> Char -> u # gmapM :: Monad m => (forall d. Data d => d -> m d) -> Char -> m Char # gmapMp :: MonadPlus m => (forall d. Data d => d -> m d) -> Char -> m Char # gmapMo :: MonadPlus m => (forall d. Data d => d -> m d) -> Char -> m Char # | |
Ord Char | |
Read Char | Since: base-2.1 |
Show Char | Since: base-2.1 |
Ix Char | Since: base-2.1 |
Generic1 (URec Char :: k -> *) | |
Functor (URec Char :: * -> *) | |
Foldable (URec Char :: * -> *) | |
Defined in Data.Foldable fold :: Monoid m => URec Char m -> m # foldMap :: Monoid m => (a -> m) -> URec Char a -> m # foldr :: (a -> b -> b) -> b -> URec Char a -> b # foldr' :: (a -> b -> b) -> b -> URec Char a -> b # foldl :: (b -> a -> b) -> b -> URec Char a -> b # foldl' :: (b -> a -> b) -> b -> URec Char a -> b # foldr1 :: (a -> a -> a) -> URec Char a -> a # foldl1 :: (a -> a -> a) -> URec Char a -> a # toList :: URec Char a -> [a] # length :: URec Char a -> Int # elem :: Eq a => a -> URec Char a -> Bool # maximum :: Ord a => URec Char a -> a # minimum :: Ord a => URec Char a -> a # | |
Traversable (URec Char :: * -> *) | |
Eq (URec Char p) | |
Ord (URec Char p) | |
Show (URec Char p) | |
Generic (URec Char p) | |
data URec Char (p :: k) | Used for marking occurrences of Since: base-4.9.0.0 |
type Rep1 (URec Char :: k -> *) | |
Defined in GHC.Generics | |
type Rep (URec Char p) | |
Defined in GHC.Generics |
Class for string-like datastructures; used by the overloaded string extension (-XOverloadedStrings in GHC).
fromString :: String -> a #
Instances
a ~ Char => IsString [a] |
Since: base-2.1 |
Defined in Data.String fromString :: String -> [a] # | |
IsString a => IsString (Identity a) | |
Defined in Data.String fromString :: String -> Identity a # | |
IsString a => IsString (Const a b) | Since: base-4.9.0.0 |
Defined in Data.String fromString :: String -> Const a b # |
Bool
Instances
Bounded Bool | Since: base-2.1 |
Enum Bool | Since: base-2.1 |
Eq Bool | |
Data Bool | Since: base-4.0.0.0 |
Defined in Data.Data gfoldl :: (forall d b. Data d => c (d -> b) -> d -> c b) -> (forall g. g -> c g) -> Bool -> c Bool # gunfold :: (forall b r. Data b => c (b -> r) -> c r) -> (forall r. r -> c r) -> Constr -> c Bool # dataTypeOf :: Bool -> DataType # dataCast1 :: Typeable t => (forall d. Data d => c (t d)) -> Maybe (c Bool) # dataCast2 :: Typeable t => (forall d e. (Data d, Data e) => c (t d e)) -> Maybe (c Bool) # gmapT :: (forall b. Data b => b -> b) -> Bool -> Bool # gmapQl :: (r -> r' -> r) -> r -> (forall d. Data d => d -> r') -> Bool -> r # gmapQr :: (r' -> r -> r) -> r -> (forall d. Data d => d -> r') -> Bool -> r # gmapQ :: (forall d. Data d => d -> u) -> Bool -> [u] # gmapQi :: Int -> (forall d. Data d => d -> u) -> Bool -> u # gmapM :: Monad m => (forall d. Data d => d -> m d) -> Bool -> m Bool # gmapMp :: MonadPlus m => (forall d. Data d => d -> m d) -> Bool -> m Bool # gmapMo :: MonadPlus m => (forall d. Data d => d -> m d) -> Bool -> m Bool # | |
Ord Bool | |
Read Bool | Since: base-2.1 |
Show Bool | |
Ix Bool | Since: base-2.1 |
Generic Bool | |
SingKind Bool | Since: base-4.9.0.0 |
SingI False | Since: base-4.9.0.0 |
Defined in GHC.Generics | |
SingI True | Since: base-4.9.0.0 |
Defined in GHC.Generics | |
type Rep Bool | |
data Sing (a :: Bool) | |
type DemoteRep Bool | |
Defined in GHC.Generics |
Case analysis for the Bool
type.
evaluates to bool
x y px
when p
is False
, and evaluates to y
when p
is True
.
This is equivalent to if p then y else x
; that is, one can
think of it as an if-then-else construct with its arguments
reordered.
Examples
Basic usage:
>>>
bool "foo" "bar" True
"bar">>>
bool "foo" "bar" False
"foo"
Confirm that
and bool
x y pif p then y else x
are
equivalent:
>>>
let p = True; x = "bar"; y = "foo"
>>>
bool x y p == if p then y else x
True>>>
let p = False
>>>
bool x y p == if p then y else x
True
Since: base-4.7.0.0
Maybe
The Maybe
type encapsulates an optional value. A value of type
either contains a value of type Maybe
aa
(represented as
),
or it is empty (represented as Just
aNothing
). Using Maybe
is a good way to
deal with errors or exceptional cases without resorting to drastic
measures such as error
.
The Maybe
type is also a monad. It is a simple kind of error
monad, where all errors are represented by Nothing
. A richer
error monad can be built using the Either
type.
Instances
Monad Maybe | Since: base-2.1 |
Functor Maybe | Since: base-2.1 |
MonadFail Maybe | Since: base-4.9.0.0 |
Defined in Control.Monad.Fail | |
Applicative Maybe | Since: base-2.1 |
Foldable Maybe | Since: base-2.1 |
Defined in Data.Foldable fold :: Monoid m => Maybe m -> m # foldMap :: Monoid m => (a -> m) -> Maybe a -> m # foldr :: (a -> b -> b) -> b -> Maybe a -> b # foldr' :: (a -> b -> b) -> b -> Maybe a -> b # foldl :: (b -> a -> b) -> b -> Maybe a -> b # foldl' :: (b -> a -> b) -> b -> Maybe a -> b # foldr1 :: (a -> a -> a) -> Maybe a -> a # foldl1 :: (a -> a -> a) -> Maybe a -> a # elem :: Eq a => a -> Maybe a -> Bool # maximum :: Ord a => Maybe a -> a # minimum :: Ord a => Maybe a -> a # | |
Traversable Maybe | Since: base-2.1 |
Alternative Maybe | Since: base-2.1 |
MonadPlus Maybe | Since: base-2.1 |
Eq a => Eq (Maybe a) | |
Data a => Data (Maybe a) | Since: base-4.0.0.0 |
Defined in Data.Data gfoldl :: (forall d b. Data d => c (d -> b) -> d -> c b) -> (forall g. g -> c g) -> Maybe a -> c (Maybe a) # gunfold :: (forall b r. Data b => c (b -> r) -> c r) -> (forall r. r -> c r) -> Constr -> c (Maybe a) # toConstr :: Maybe a -> Constr # dataTypeOf :: Maybe a -> DataType # dataCast1 :: Typeable t => (forall d. Data d => c (t d)) -> Maybe (c (Maybe a)) # dataCast2 :: Typeable t => (forall d e. (Data d, Data e) => c (t d e)) -> Maybe (c (Maybe a)) # gmapT :: (forall b. Data b => b -> b) -> Maybe a -> Maybe a # gmapQl :: (r -> r' -> r) -> r -> (forall d. Data d => d -> r') -> Maybe a -> r # gmapQr :: (r' -> r -> r) -> r -> (forall d. Data d => d -> r') -> Maybe a -> r # gmapQ :: (forall d. Data d => d -> u) -> Maybe a -> [u] # gmapQi :: Int -> (forall d. Data d => d -> u) -> Maybe a -> u # gmapM :: Monad m => (forall d. Data d => d -> m d) -> Maybe a -> m (Maybe a) # gmapMp :: MonadPlus m => (forall d. Data d => d -> m d) -> Maybe a -> m (Maybe a) # gmapMo :: MonadPlus m => (forall d. Data d => d -> m d) -> Maybe a -> m (Maybe a) # | |
Ord a => Ord (Maybe a) | |
Read a => Read (Maybe a) | Since: base-2.1 |
Show a => Show (Maybe a) | |
Generic (Maybe a) | |
Semigroup a => Semigroup (Maybe a) | Since: base-4.9.0.0 |
Semigroup a => Monoid (Maybe a) | Lift a semigroup into Since 4.11.0: constraint on inner Since: base-2.1 |
SingKind a => SingKind (Maybe a) | Since: base-4.9.0.0 |
Generic1 Maybe | |
SingI (Nothing :: Maybe a) | Since: base-4.9.0.0 |
Defined in GHC.Generics | |
SingI a2 => SingI (Just a2 :: Maybe a1) | Since: base-4.9.0.0 |
Defined in GHC.Generics | |
type Rep (Maybe a) | |
data Sing (b :: Maybe a) | |
type DemoteRep (Maybe a) | |
Defined in GHC.Generics | |
type Rep1 Maybe | |
maybe :: b -> (a -> b) -> Maybe a -> b #
The maybe
function takes a default value, a function, and a Maybe
value. If the Maybe
value is Nothing
, the function returns the
default value. Otherwise, it applies the function to the value inside
the Just
and returns the result.
Examples
Basic usage:
>>>
maybe False odd (Just 3)
True
>>>
maybe False odd 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
""
fromMaybe :: a -> Maybe a -> a #
The fromMaybe
function takes a default value and and Maybe
value. If the Maybe
is Nothing
, it returns the default values;
otherwise, it returns the value contained in the Maybe
.
Examples
Basic usage:
>>>
fromMaybe "" (Just "Hello, World!")
"Hello, World!"
>>>
fromMaybe "" Nothing
""
Read an integer from a string using readMaybe
. If we fail to
parse an integer, we want to return 0
by default:
>>>
import Text.Read ( readMaybe )
>>>
fromMaybe 0 (readMaybe "5")
5>>>
fromMaybe 0 (readMaybe "")
0
mapMaybe :: (a -> Maybe b) -> [a] -> [b] #
The mapMaybe
function is a version of map
which can throw
out elements. In particular, the functional argument returns
something of type
. If this is Maybe
bNothing
, no element
is added on to the result list. If it is
, then Just
bb
is
included in the result list.
Examples
Using
is a shortcut for mapMaybe
f x
in most cases:catMaybes
$ map
f x
>>>
import Text.Read ( readMaybe )
>>>
let readMaybeInt = readMaybe :: String -> Maybe Int
>>>
mapMaybe readMaybeInt ["1", "Foo", "3"]
[1,3]>>>
catMaybes $ map readMaybeInt ["1", "Foo", "3"]
[1,3]
If we map the Just
constructor, the entire list should be returned:
>>>
mapMaybe Just [1,2,3]
[1,2,3]
catMaybes :: [Maybe a] -> [a] #
The catMaybes
function takes a list of Maybe
s and returns
a list of all the Just
values.
Examples
Basic usage:
>>>
catMaybes [Just 1, Nothing, Just 3]
[1,3]
When constructing a list of Maybe
values, catMaybes
can be used
to return all of the "success" results (if the list is the result
of a map
, then mapMaybe
would be more appropriate):
>>>
import Text.Read ( readMaybe )
>>>
[readMaybe x :: Maybe Int | x <- ["1", "Foo", "3"] ]
[Just 1,Nothing,Just 3]>>>
catMaybes $ [readMaybe x :: Maybe Int | x <- ["1", "Foo", "3"] ]
[1,3]
listToMaybe :: [a] -> Maybe a #
The listToMaybe
function returns Nothing
on an empty list
or
where Just
aa
is the first element of the list.
Examples
Basic usage:
>>>
listToMaybe []
Nothing
>>>
listToMaybe [9]
Just 9
>>>
listToMaybe [1,2,3]
Just 1
Composing maybeToList
with listToMaybe
should be the identity
on singleton/empty lists:
>>>
maybeToList $ listToMaybe [5]
[5]>>>
maybeToList $ listToMaybe []
[]
But not on lists with more than one element:
>>>
maybeToList $ listToMaybe [1,2,3]
[1]
maybeToList :: Maybe a -> [a] #
The maybeToList
function returns an empty list when given
Nothing
or a singleton list when not given Nothing
.
Examples
Basic usage:
>>>
maybeToList (Just 7)
[7]
>>>
maybeToList Nothing
[]
One can use maybeToList
to avoid pattern matching when combined
with a function that (safely) works on lists:
>>>
import Text.Read ( readMaybe )
>>>
sum $ maybeToList (readMaybe "3")
3>>>
sum $ maybeToList (readMaybe "")
0
Either
The Either
type represents values with two possibilities: a value of
type
is either Either
a b
or Left
a
.Right
b
The Either
type is sometimes used to represent a value which is
either correct or an error; by convention, the Left
constructor is
used to hold an error value and the Right
constructor is used to
hold a correct value (mnemonic: "right" also means "correct").
Examples
The type
is the type of values which can be either
a Either
String
Int
String
or an Int
. The Left
constructor can be used only on
String
s, and the Right
constructor can be used only on Int
s:
>>>
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 Int
s.
>>>
:{
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"
Instances
Monad (Either e) | Since: base-4.4.0.0 |
Functor (Either a) | Since: base-3.0 |
Applicative (Either e) | Since: base-3.0 |
Foldable (Either a) | Since: base-4.7.0.0 |
Defined in Data.Foldable fold :: Monoid m => Either a m -> m # foldMap :: Monoid m => (a0 -> m) -> Either a a0 -> m # foldr :: (a0 -> b -> b) -> b -> Either a a0 -> b # foldr' :: (a0 -> b -> b) -> b -> Either a a0 -> b # foldl :: (b -> a0 -> b) -> b -> Either a a0 -> b # foldl' :: (b -> a0 -> b) -> b -> Either a a0 -> b # foldr1 :: (a0 -> a0 -> a0) -> Either a a0 -> a0 # foldl1 :: (a0 -> a0 -> a0) -> Either a a0 -> a0 # toList :: Either a a0 -> [a0] # length :: Either a a0 -> Int # elem :: Eq a0 => a0 -> Either a a0 -> Bool # maximum :: Ord a0 => Either a a0 -> a0 # minimum :: Ord a0 => Either a a0 -> a0 # | |
Traversable (Either a) | Since: base-4.7.0.0 |
Generic1 (Either a :: * -> *) | |
(Eq a, Eq b) => Eq (Either a b) | |
(Data a, Data b) => Data (Either a b) | Since: base-4.0.0.0 |
Defined in Data.Data gfoldl :: (forall d b0. Data d => c (d -> b0) -> d -> c b0) -> (forall g. g -> c g) -> Either a b -> c (Either a b) # gunfold :: (forall b0 r. Data b0 => c (b0 -> r) -> c r) -> (forall r. r -> c r) -> Constr -> c (Either a b) # toConstr :: Either a b -> Constr # dataTypeOf :: Either a b -> DataType # dataCast1 :: Typeable t => (forall d. Data d => c (t d)) -> Maybe (c (Either a b)) # dataCast2 :: Typeable t => (forall d e. (Data d, Data e) => c (t d e)) -> Maybe (c (Either a b)) # gmapT :: (forall b0. Data b0 => b0 -> b0) -> Either a b -> Either a b # gmapQl :: (r -> r' -> r) -> r -> (forall d. Data d => d -> r') -> Either a b -> r # gmapQr :: (r' -> r -> r) -> r -> (forall d. Data d => d -> r') -> Either a b -> r # gmapQ :: (forall d. Data d => d -> u) -> Either a b -> [u] # gmapQi :: Int -> (forall d. Data d => d -> u) -> Either a b -> u # gmapM :: Monad m => (forall d. Data d => d -> m d) -> Either a b -> m (Either a b) # gmapMp :: MonadPlus m => (forall d. Data d => d -> m d) -> Either a b -> m (Either a b) # gmapMo :: MonadPlus m => (forall d. Data d => d -> m d) -> Either a b -> m (Either a b) # | |
(Ord a, Ord b) => Ord (Either a b) | |
(Read a, Read b) => Read (Either a b) | |
(Show a, Show b) => Show (Either a b) | |
Generic (Either a b) | |
Semigroup (Either a b) | Since: base-4.9.0.0 |
type Rep1 (Either a :: * -> *) | |
Defined in GHC.Generics type Rep1 (Either a :: * -> *) = D1 (MetaData "Either" "Data.Either" "base" False) (C1 (MetaCons "Left" PrefixI False) (S1 (MetaSel (Nothing :: Maybe Symbol) NoSourceUnpackedness NoSourceStrictness DecidedLazy) (Rec0 a)) :+: C1 (MetaCons "Right" PrefixI False) (S1 (MetaSel (Nothing :: Maybe Symbol) NoSourceUnpackedness NoSourceStrictness DecidedLazy) Par1)) | |
type Rep (Either a b) | |
Defined in GHC.Generics type Rep (Either a b) = D1 (MetaData "Either" "Data.Either" "base" False) (C1 (MetaCons "Left" PrefixI False) (S1 (MetaSel (Nothing :: Maybe Symbol) NoSourceUnpackedness NoSourceStrictness DecidedLazy) (Rec0 a)) :+: C1 (MetaCons "Right" PrefixI False) (S1 (MetaSel (Nothing :: Maybe Symbol) NoSourceUnpackedness NoSourceStrictness DecidedLazy) (Rec0 b))) |
either :: (a -> c) -> (b -> c) -> Either a b -> c #
Case analysis for the Either
type.
If the value is
, apply the first function to Left
aa
;
if it is
, apply the second function to Right
bb
.
Examples
We create two values of type
, one using the
Either
String
Int
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
fromLeft :: a -> Either a b -> a #
Return the contents of a Left
-value or a default value otherwise.
Examples
Basic usage:
>>>
fromLeft 1 (Left 3)
3>>>
fromLeft 1 (Right "foo")
1
Since: base-4.10.0.0
fromRight :: b -> Either a b -> b #
Return the contents of a Right
-value or a default value otherwise.
Examples
Basic usage:
>>>
fromRight 1 (Right 3)
3>>>
fromRight 1 (Left "foo")
1
Since: base-4.10.0.0
isLeft :: Either a b -> Bool #
Return True
if the given value is a Left
-value, False
otherwise.
Examples
Basic usage:
>>>
isLeft (Left "foo")
True>>>
isLeft (Right 3)
False
Assuming a Left
value signifies some sort of error, we can use
isLeft
to write a very simple error-reporting function that does
absolutely nothing in the case of success, and outputs "ERROR" if
any error occurred.
This example shows how isLeft
might be used to avoid pattern
matching when one does not care about the value contained in the
constructor:
>>>
import Control.Monad ( when )
>>>
let report e = when (isLeft e) $ putStrLn "ERROR"
>>>
report (Right 1)
>>>
report (Left "parse error")
ERROR
Since: base-4.7.0.0
isRight :: Either a b -> Bool #
Return True
if the given value is a Right
-value, False
otherwise.
Examples
Basic usage:
>>>
isRight (Left "foo")
False>>>
isRight (Right 3)
True
Assuming a Left
value signifies some sort of error, we can use
isRight
to write a very simple reporting function that only
outputs "SUCCESS" when a computation has succeeded.
This example shows how isRight
might be used to avoid pattern
matching when one does not care about the value contained in the
constructor:
>>>
import Control.Monad ( when )
>>>
let report e = when (isRight e) $ putStrLn "SUCCESS"
>>>
report (Left "parse error")
>>>
report (Right 1)
SUCCESS
Since: base-4.7.0.0
partitionEithers :: [Either a b] -> ([a], [b]) #
Partitions a list of Either
into two lists.
All the Left
elements are extracted, in order, to the first
component of the output. Similarly the Right
elements are extracted
to the second component of the output.
Examples
Basic usage:
>>>
let list = [ Left "foo", Right 3, Left "bar", Right 7, Left "baz" ]
>>>
partitionEithers list
(["foo","bar","baz"],[3,7])
The pair returned by
should be the same
pair as partitionEithers
x(
:lefts
x, rights
x)
>>>
let list = [ Left "foo", Right 3, Left "bar", Right 7, Left "baz" ]
>>>
partitionEithers list == (lefts list, rights list)
True
Eq
and Ord
Instances
Bounded Ordering | Since: base-2.1 |
Enum Ordering | Since: base-2.1 |
Eq Ordering | |
Data Ordering | Since: base-4.0.0.0 |
Defined in Data.Data gfoldl :: (forall d b. Data d => c (d -> b) -> d -> c b) -> (forall g. g -> c g) -> Ordering -> c Ordering # gunfold :: (forall b r. Data b => c (b -> r) -> c r) -> (forall r. r -> c r) -> Constr -> c Ordering # toConstr :: Ordering -> Constr # dataTypeOf :: Ordering -> DataType # dataCast1 :: Typeable t => (forall d. Data d => c (t d)) -> Maybe (c Ordering) # dataCast2 :: Typeable t => (forall d e. (Data d, Data e) => c (t d e)) -> Maybe (c Ordering) # gmapT :: (forall b. Data b => b -> b) -> Ordering -> Ordering # gmapQl :: (r -> r' -> r) -> r -> (forall d. Data d => d -> r') -> Ordering -> r # gmapQr :: (r' -> r -> r) -> r -> (forall d. Data d => d -> r') -> Ordering -> r # gmapQ :: (forall d. Data d => d -> u) -> Ordering -> [u] # gmapQi :: Int -> (forall d. Data d => d -> u) -> Ordering -> u # gmapM :: Monad m => (forall d. Data d => d -> m d) -> Ordering -> m Ordering # gmapMp :: MonadPlus m => (forall d. Data d => d -> m d) -> Ordering -> m Ordering # gmapMo :: MonadPlus m => (forall d. Data d => d -> m d) -> Ordering -> m Ordering # | |
Ord Ordering | |
Defined in GHC.Classes | |
Read Ordering | Since: base-2.1 |
Show Ordering | |
Ix Ordering | Since: base-2.1 |
Defined in GHC.Arr | |
Generic Ordering | |
Semigroup Ordering | Since: base-4.9.0.0 |
Monoid Ordering | Since: base-2.1 |
type Rep Ordering | |
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
.
Instances
Eq Bool | |
Eq Char | |
Eq Double | |
Eq Float | |
Eq Int | |
Eq Int8 | Since: base-2.1 |
Eq Int16 | Since: base-2.1 |
Eq Int32 | Since: base-2.1 |
Eq Int64 | Since: base-2.1 |
Eq Integer | |
Eq Ordering | |
Eq Word | |
Eq Word8 | Since: base-2.1 |
Eq Word16 | Since: base-2.1 |
Eq Word32 | Since: base-2.1 |
Eq Word64 | Since: base-2.1 |
Eq SomeTypeRep | |
Defined in Data.Typeable.Internal (==) :: SomeTypeRep -> SomeTypeRep -> Bool # (/=) :: SomeTypeRep -> SomeTypeRep -> Bool # | |
Eq () | |
Eq TyCon | |
Eq Module | |
Eq TrName | |
Eq BigNat | |
Eq Constr | Equality of constructors Since: base-4.0.0.0 |
Eq DataRep | |
Eq ConstrRep | |
Eq Fixity | |
Eq HandlePosn | Since: base-4.1.0.0 |
Defined in GHC.IO.Handle (==) :: HandlePosn -> HandlePosn -> Bool # (/=) :: HandlePosn -> HandlePosn -> Bool # | |
Eq Handle | Since: base-4.1.0.0 |
Eq BufferMode | |
Defined in GHC.IO.Handle.Types (==) :: BufferMode -> BufferMode -> Bool # (/=) :: BufferMode -> BufferMode -> Bool # | |
Eq Newline | |
Eq NewlineMode | |
Defined in GHC.IO.Handle.Types (==) :: NewlineMode -> NewlineMode -> Bool # (/=) :: NewlineMode -> NewlineMode -> Bool # | |
Eq IODeviceType | |
Defined in GHC.IO.Device (==) :: IODeviceType -> IODeviceType -> Bool # (/=) :: IODeviceType -> IODeviceType -> Bool # | |
Eq SeekMode | |
Eq CodingProgress | |
Defined in GHC.IO.Encoding.Types (==) :: CodingProgress -> CodingProgress -> Bool # (/=) :: CodingProgress -> CodingProgress -> Bool # | |
Eq MaskingState | |
Defined in GHC.IO (==) :: MaskingState -> MaskingState -> Bool # (/=) :: MaskingState -> MaskingState -> Bool # | |
Eq All | |
Eq Any | |
Eq Fixity | |
Eq Associativity | |
Defined in GHC.Generics (==) :: Associativity -> Associativity -> Bool # (/=) :: Associativity -> Associativity -> Bool # | |
Eq SourceUnpackedness | |
Defined in GHC.Generics (==) :: SourceUnpackedness -> SourceUnpackedness -> Bool # (/=) :: SourceUnpackedness -> SourceUnpackedness -> Bool # | |
Eq SourceStrictness | |
Defined in GHC.Generics (==) :: SourceStrictness -> SourceStrictness -> Bool # (/=) :: SourceStrictness -> SourceStrictness -> Bool # | |
Eq DecidedStrictness | |
Defined in GHC.Generics (==) :: DecidedStrictness -> DecidedStrictness -> Bool # (/=) :: DecidedStrictness -> DecidedStrictness -> Bool # | |
Eq IOMode | |
Eq Lexeme | |
Eq Number | |
Eq GeneralCategory | |
Defined in GHC.Unicode (==) :: GeneralCategory -> GeneralCategory -> Bool # (/=) :: GeneralCategory -> GeneralCategory -> Bool # | |
Eq SrcLoc | |
Eq a => Eq [a] | |
Eq a => Eq (Maybe a) | |
Eq a => Eq (Ratio a) | |
Eq p => Eq (Par1 p) | |
Eq a => Eq (Min a) | |
Eq a => Eq (Max a) | |
Eq a => Eq (First a) | |
Eq a => Eq (Last a) | |
Eq m => Eq (WrappedMonoid m) | |
Defined in Data.Semigroup (==) :: WrappedMonoid m -> WrappedMonoid m -> Bool # (/=) :: WrappedMonoid m -> WrappedMonoid m -> Bool # | |
Eq a => Eq (Option a) | |
Eq a => Eq (ZipList a) | |
Eq a => Eq (Dual a) | |
Eq a => Eq (Sum a) | |
Eq a => Eq (Product a) | |
Eq a => Eq (Down a) | |
Eq a => Eq (NonEmpty a) | |
(Eq a, Eq b) => Eq (Either a b) | |
Eq (V1 p) | Since: base-4.9.0.0 |
Eq (U1 p) | Since: base-4.9.0.0 |
Eq (TypeRep a) | Since: base-2.1 |
(Eq a, Eq b) => Eq (a, b) | |
(Ix i, Eq e) => Eq (Array i e) | Since: base-2.1 |
Eq a => Eq (Arg a b) | Since: base-4.9.0.0 |
Eq (f p) => Eq (Rec1 f p) | |
Eq (URec (Ptr ()) p) | |
Eq (URec Char p) | |
Eq (URec Double p) | |
Eq (URec Float p) | |
Eq (URec Int p) | |
Eq (URec Word p) | |
(Eq a, Eq b, Eq c) => Eq (a, b, c) | |
Eq (STArray s i e) | Since: base-2.1 |
Eq a => Eq (Const a b) | |
Eq (f a) => Eq (Alt f a) | |
Eq c => Eq (K1 i c p) | |
(Eq (f p), Eq (g p)) => Eq ((f :+: g) p) | |
(Eq (f p), Eq (g p)) => Eq ((f :*: g) p) | |
(Eq a, Eq b, Eq c, Eq d) => Eq (a, b, c, d) | |
Eq (f p) => Eq (M1 i c f p) | |
Eq (f (g p)) => Eq ((f :.: g) p) | |
(Eq a, Eq b, Eq c, Eq d, Eq e) => Eq (a, b, c, d, e) | |
(Eq a, Eq b, Eq c, Eq d, Eq e, Eq f) => Eq (a, b, c, d, e, f) | |
(Eq a, Eq b, Eq c, Eq d, Eq e, Eq f, Eq g) => Eq (a, b, c, d, e, f, g) | |
(Eq a, Eq b, Eq c, Eq d, Eq e, Eq f, Eq g, Eq h) => Eq (a, b, c, d, e, f, g, h) | |
(Eq a, Eq b, Eq c, Eq d, Eq e, Eq f, Eq g, Eq h, Eq i) => Eq (a, b, c, d, e, f, g, h, i) | |
(Eq a, Eq b, Eq c, Eq d, Eq e, Eq f, Eq g, Eq h, Eq i, Eq j) => Eq (a, b, c, d, e, f, g, h, i, j) | |
(Eq a, Eq b, Eq c, Eq d, Eq e, Eq f, Eq g, Eq h, Eq i, Eq j, Eq k) => Eq (a, b, c, d, e, f, g, h, i, j, k) | |
(Eq a, Eq b, Eq c, Eq d, Eq e, Eq f, Eq g, Eq h, Eq i, Eq j, Eq k, Eq l) => Eq (a, b, c, d, e, f, g, h, i, j, k, l) | |
(Eq a, Eq b, Eq c, Eq d, Eq e, Eq f, Eq g, Eq h, Eq i, Eq j, Eq k, Eq l, Eq m) => Eq (a, b, c, d, e, f, g, h, i, j, k, l, m) | |
(Eq a, Eq b, Eq c, Eq d, Eq e, Eq f, Eq g, Eq h, Eq i, Eq j, Eq k, Eq l, Eq m, Eq n) => Eq (a, b, c, d, e, f, g, h, i, j, k, l, m, n) | |
(Eq a, Eq b, Eq c, Eq d, Eq e, Eq f, Eq g, Eq h, Eq i, Eq j, Eq k, Eq l, Eq m, Eq n, Eq o) => Eq (a, b, c, d, e, f, g, h, i, j, k, l, m, n, o) | |
The Ord
class is used for totally ordered datatypes.
Instances of Ord
can be derived for any user-defined
datatype whose constituent types are in Ord
. The declared order
of the constructors in the data declaration determines the ordering
in derived Ord
instances. The Ordering
datatype allows a single
comparison to determine the precise ordering of two objects.
Minimal complete definition: either compare
or <=
.
Using compare
can be more efficient for complex types.
compare :: a -> a -> Ordering #
(<) :: a -> a -> Bool infix 4 #
(<=) :: a -> a -> Bool infix 4 #
(>) :: a -> a -> Bool infix 4 #
Instances
Ord Bool | |
Ord Char | |
Ord Double | |
Ord Float | |
Ord Int | |
Ord Int8 | Since: base-2.1 |
Ord Int16 | Since: base-2.1 |
Ord Int32 | Since: base-2.1 |
Ord Int64 | Since: base-2.1 |
Ord Integer | |
Ord Ordering | |
Defined in GHC.Classes | |
Ord Word | |
Ord Word8 | Since: base-2.1 |
Ord Word16 | Since: base-2.1 |
Ord Word32 | Since: base-2.1 |
Ord Word64 | Since: base-2.1 |
Ord SomeTypeRep | |
Defined in Data.Typeable.Internal compare :: SomeTypeRep -> SomeTypeRep -> Ordering # (<) :: SomeTypeRep -> SomeTypeRep -> Bool # (<=) :: SomeTypeRep -> SomeTypeRep -> Bool # (>) :: SomeTypeRep -> SomeTypeRep -> Bool # (>=) :: SomeTypeRep -> SomeTypeRep -> Bool # max :: SomeTypeRep -> SomeTypeRep -> SomeTypeRep # min :: SomeTypeRep -> SomeTypeRep -> SomeTypeRep # | |
Ord () | |
Ord TyCon | |
Ord BigNat | |
Ord BufferMode | |
Defined in GHC.IO.Handle.Types compare :: BufferMode -> BufferMode -> Ordering # (<) :: BufferMode -> BufferMode -> Bool # (<=) :: BufferMode -> BufferMode -> Bool # (>) :: BufferMode -> BufferMode -> Bool # (>=) :: BufferMode -> BufferMode -> Bool # max :: BufferMode -> BufferMode -> BufferMode # min :: BufferMode -> BufferMode -> BufferMode # | |
Ord Newline | |
Ord NewlineMode | |
Defined in GHC.IO.Handle.Types compare :: NewlineMode -> NewlineMode -> Ordering # (<) :: NewlineMode -> NewlineMode -> Bool # (<=) :: NewlineMode -> NewlineMode -> Bool # (>) :: NewlineMode -> NewlineMode -> Bool # (>=) :: NewlineMode -> NewlineMode -> Bool # max :: NewlineMode -> NewlineMode -> NewlineMode # min :: NewlineMode -> NewlineMode -> NewlineMode # | |
Ord SeekMode | |
Defined in GHC.IO.Device | |
Ord All | |
Ord Any | |
Ord Fixity | |
Ord Associativity | |
Defined in GHC.Generics compare :: Associativity -> Associativity -> Ordering # (<) :: Associativity -> Associativity -> Bool # (<=) :: Associativity -> Associativity -> Bool # (>) :: Associativity -> Associativity -> Bool # (>=) :: Associativity -> Associativity -> Bool # max :: Associativity -> Associativity -> Associativity # min :: Associativity -> Associativity -> Associativity # | |
Ord SourceUnpackedness | |
Defined in GHC.Generics compare :: SourceUnpackedness -> SourceUnpackedness -> Ordering # (<) :: SourceUnpackedness -> SourceUnpackedness -> Bool # (<=) :: SourceUnpackedness -> SourceUnpackedness -> Bool # (>) :: SourceUnpackedness -> SourceUnpackedness -> Bool # (>=) :: SourceUnpackedness -> SourceUnpackedness -> Bool # max :: SourceUnpackedness -> SourceUnpackedness -> SourceUnpackedness # min :: SourceUnpackedness -> SourceUnpackedness -> SourceUnpackedness # | |
Ord SourceStrictness | |
Defined in GHC.Generics compare :: SourceStrictness -> SourceStrictness -> Ordering # (<) :: SourceStrictness -> SourceStrictness -> Bool # (<=) :: SourceStrictness -> SourceStrictness -> Bool # (>) :: SourceStrictness -> SourceStrictness -> Bool # (>=) :: SourceStrictness -> SourceStrictness -> Bool # max :: SourceStrictness -> SourceStrictness -> SourceStrictness # min :: SourceStrictness -> SourceStrictness -> SourceStrictness # | |
Ord DecidedStrictness | |
Defined in GHC.Generics compare :: DecidedStrictness -> DecidedStrictness -> Ordering # (<) :: DecidedStrictness -> DecidedStrictness -> Bool # (<=) :: DecidedStrictness -> DecidedStrictness -> Bool # (>) :: DecidedStrictness -> DecidedStrictness -> Bool # (>=) :: DecidedStrictness -> DecidedStrictness -> Bool # max :: DecidedStrictness -> DecidedStrictness -> DecidedStrictness # min :: DecidedStrictness -> DecidedStrictness -> DecidedStrictness # | |
Ord IOMode | |
Ord GeneralCategory | |
Defined in GHC.Unicode compare :: GeneralCategory -> GeneralCategory -> Ordering # (<) :: GeneralCategory -> GeneralCategory -> Bool # (<=) :: GeneralCategory -> GeneralCategory -> Bool # (>) :: GeneralCategory -> GeneralCategory -> Bool # (>=) :: GeneralCategory -> GeneralCategory -> Bool # max :: GeneralCategory -> GeneralCategory -> GeneralCategory # min :: GeneralCategory -> GeneralCategory -> GeneralCategory # | |
Ord a => Ord [a] | |
Ord a => Ord (Maybe a) | |
Integral a => Ord (Ratio a) | Since: base-2.0.1 |
Ord p => Ord (Par1 p) | |
Ord a => Ord (Min a) | |
Ord a => Ord (Max a) | |
Ord a => Ord (First a) | |
Ord a => Ord (Last a) | |
Ord m => Ord (WrappedMonoid m) | |
Defined in Data.Semigroup compare :: WrappedMonoid m -> WrappedMonoid m -> Ordering # (<) :: WrappedMonoid m -> WrappedMonoid m -> Bool # (<=) :: WrappedMonoid m -> WrappedMonoid m -> Bool # (>) :: WrappedMonoid m -> WrappedMonoid m -> Bool # (>=) :: WrappedMonoid m -> WrappedMonoid m -> Bool # max :: WrappedMonoid m -> WrappedMonoid m -> WrappedMonoid m # min :: WrappedMonoid m -> WrappedMonoid m -> WrappedMonoid m # | |
Ord a => Ord (Option a) | |
Defined in Data.Semigroup | |
Ord a => Ord (ZipList a) | |
Defined in Control.Applicative | |
Ord a => Ord (Dual a) | |
Ord a => Ord (Sum a) | |
Ord a => Ord (Product a) | |
Defined in Data.Semigroup.Internal | |
Ord a => Ord (Down a) | Since: base-4.6.0.0 |
Ord a => Ord (NonEmpty a) | |
(Ord a, Ord b) => Ord (Either a b) | |
Ord (V1 p) | Since: base-4.9.0.0 |
Ord (U1 p) | Since: base-4.9.0.0 |
Ord (TypeRep a) | Since: base-4.4.0.0 |
Defined in Data.Typeable.Internal | |
(Ord a, Ord b) => Ord (a, b) | |
(Ix i, Ord e) => Ord (Array i e) | Since: base-2.1 |
Defined in GHC.Arr | |
Ord a => Ord (Arg a b) | Since: base-4.9.0.0 |
Ord (f p) => Ord (Rec1 f p) | |
Defined in GHC.Generics | |
Ord (URec (Ptr ()) p) | |
Defined in GHC.Generics 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) | |
Ord (URec Double p) | |
Defined in GHC.Generics compare :: URec Double p -> URec Double p -> Ordering # (<) :: URec Double p -> URec Double p -> Bool # (<=) :: URec Double p -> URec Double p -> Bool # (>) :: URec Double p -> URec Double p -> Bool # (>=) :: URec Double p -> URec Double p -> Bool # | |
Ord (URec Float p) | |
Defined in GHC.Generics | |
Ord (URec Int p) | |
Ord (URec Word p) | |
(Ord a, Ord b, Ord c) => Ord (a, b, c) | |
Defined in GHC.Classes | |
Ord a => Ord (Const a b) | |
Defined in Data.Functor.Const | |
Ord (f a) => Ord (Alt f a) | |
Ord c => Ord (K1 i c p) | |
Defined in GHC.Generics | |
(Ord (f p), Ord (g p)) => Ord ((f :+: g) p) | |
(Ord (f p), Ord (g p)) => Ord ((f :*: g) p) | |
(Ord a, Ord b, Ord c, Ord d) => Ord (a, b, c, d) | |
Defined in GHC.Classes | |
Ord (f p) => Ord (M1 i c f p) | |
Ord (f (g p)) => Ord ((f :.: g) p) | |
(Ord a, Ord b, Ord c, Ord d, Ord e) => Ord (a, b, c, d, e) | |
Defined in GHC.Classes 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) | |
Defined in GHC.Classes compare :: (a, b, c, d, e, f) -> (a, b, c, d, e, f) -> Ordering # (<) :: (a, b, c, d, e, f) -> (a, b, c, d, e, f) -> Bool # (<=) :: (a, b, c, d, e, f) -> (a, b, c, d, e, f) -> Bool # (>) :: (a, b, c, d, e, f) -> (a, b, c, d, e, f) -> Bool # (>=) :: (a, b, c, d, e, f) -> (a, b, c, d, e, f) -> Bool # max :: (a, b, c, d, e, f) -> (a, b, c, d, e, f) -> (a, b, c, d, e, f) # min :: (a, b, c, d, e, f) -> (a, b, c, d, e, f) -> (a, b, c, d, e, f) # | |
(Ord a, Ord b, Ord c, Ord d, Ord e, Ord f, Ord g) => Ord (a, b, c, d, e, f, g) | |
Defined in GHC.Classes compare :: (a, b, c, d, e, f, g) -> (a, b, c, d, e, f, g) -> Ordering # (<) :: (a, b, c, d, e, f, g) -> (a, b, c, d, e, f, g) -> Bool # (<=) :: (a, b, c, d, e, f, g) -> (a, b, c, d, e, f, g) -> Bool # (>) :: (a, b, c, d, e, f, g) -> (a, b, c, d, e, f, g) -> Bool # (>=) :: (a, b, c, d, e, f, g) -> (a, b, c, d, e, f, g) -> Bool # max :: (a, b, c, d, e, f, g) -> (a, b, c, d, e, f, g) -> (a, b, c, d, e, f, g) # min :: (a, b, c, d, e, f, g) -> (a, b, c, d, e, f, g) -> (a, b, c, d, e, f, g) # | |
(Ord a, Ord b, Ord c, Ord d, Ord e, Ord f, Ord g, Ord h) => Ord (a, b, c, d, e, f, g, h) | |
Defined in GHC.Classes compare :: (a, b, c, d, e, f, g, h) -> (a, b, c, d, e, f, g, h) -> Ordering # (<) :: (a, b, c, d, e, f, g, h) -> (a, b, c, d, e, f, g, h) -> Bool # (<=) :: (a, b, c, d, e, f, g, h) -> (a, b, c, d, e, f, g, h) -> Bool # (>) :: (a, b, c, d, e, f, g, h) -> (a, b, c, d, e, f, g, h) -> Bool # (>=) :: (a, b, c, d, e, f, g, h) -> (a, b, c, d, e, f, g, h) -> Bool # max :: (a, b, c, d, e, f, g, h) -> (a, b, c, d, e, f, g, h) -> (a, b, c, d, e, f, g, h) # min :: (a, b, c, d, e, f, g, h) -> (a, b, c, d, e, f, g, h) -> (a, b, c, d, e, f, g, h) # | |
(Ord a, Ord b, Ord c, Ord d, Ord e, Ord f, Ord g, Ord h, Ord i) => Ord (a, b, c, d, e, f, g, h, i) | |
Defined in GHC.Classes compare :: (a, b, c, d, e, f, g, h, i) -> (a, b, c, d, e, f, g, h, i) -> Ordering # (<) :: (a, b, c, d, e, f, g, h, i) -> (a, b, c, d, e, f, g, h, i) -> Bool # (<=) :: (a, b, c, d, e, f, g, h, i) -> (a, b, c, d, e, f, g, h, i) -> Bool # (>) :: (a, b, c, d, e, f, g, h, i) -> (a, b, c, d, e, f, g, h, i) -> Bool # (>=) :: (a, b, c, d, e, f, g, h, i) -> (a, b, c, d, e, f, g, h, i) -> Bool # max :: (a, b, c, d, e, f, g, h, i) -> (a, b, c, d, e, f, g, h, i) -> (a, b, c, d, e, f, g, h, i) # min :: (a, b, c, d, e, f, g, h, i) -> (a, b, c, d, e, f, g, h, i) -> (a, b, c, d, e, f, g, h, i) # | |
(Ord a, Ord b, Ord c, Ord d, Ord e, Ord f, Ord g, Ord h, Ord i, Ord j) => Ord (a, b, c, d, e, f, g, h, i, j) | |
Defined in GHC.Classes compare :: (a, b, c, d, e, f, g, h, i, j) -> (a, b, c, d, e, f, g, h, i, j) -> Ordering # (<) :: (a, b, c, d, e, f, g, h, i, j) -> (a, b, c, d, e, f, g, h, i, j) -> Bool # (<=) :: (a, b, c, d, e, f, g, h, i, j) -> (a, b, c, d, e, f, g, h, i, j) -> Bool # (>) :: (a, b, c, d, e, f, g, h, i, j) -> (a, b, c, d, e, f, g, h, i, j) -> Bool # (>=) :: (a, b, c, d, e, f, g, h, i, j) -> (a, b, c, d, e, f, g, h, i, j) -> Bool # max :: (a, b, c, d, e, f, g, h, i, j) -> (a, b, c, d, e, f, g, h, i, j) -> (a, b, c, d, e, f, g, h, i, j) # min :: (a, b, c, d, e, f, g, h, i, j) -> (a, b, c, d, e, f, g, h, i, j) -> (a, b, c, d, e, f, g, h, i, j) # | |
(Ord a, Ord b, Ord c, Ord d, Ord e, Ord f, Ord g, Ord h, Ord i, Ord j, Ord k) => Ord (a, b, c, d, e, f, g, h, i, j, k) | |
Defined in GHC.Classes compare :: (a, b, c, d, e, f, g, h, i, j, k) -> (a, b, c, d, e, f, g, h, i, j, k) -> Ordering # (<) :: (a, b, c, d, e, f, g, h, i, j, k) -> (a, b, c, d, e, f, g, h, i, j, k) -> Bool # (<=) :: (a, b, c, d, e, f, g, h, i, j, k) -> (a, b, c, d, e, f, g, h, i, j, k) -> Bool # (>) :: (a, b, c, d, e, f, g, h, i, j, k) -> (a, b, c, d, e, f, g, h, i, j, k) -> Bool # (>=) :: (a, b, c, d, e, f, g, h, i, j, k) -> (a, b, c, d, e, f, g, h, i, j, k) -> Bool # max :: (a, b, c, d, e, f, g, h, i, j, k) -> (a, b, c, d, e, f, g, h, i, j, k) -> (a, b, c, d, e, f, g, h, i, j, k) # min :: (a, b, c, d, e, f, g, h, i, j, k) -> (a, b, c, d, e, f, g, h, i, j, k) -> (a, b, c, d, e, f, g, h, i, j, k) # | |
(Ord a, Ord b, Ord c, Ord d, Ord e, Ord f, Ord g, Ord h, Ord i, Ord j, Ord k, Ord l) => Ord (a, b, c, d, e, f, g, h, i, j, k, l) | |
Defined in GHC.Classes compare :: (a, b, c, d, e, f, g, h, i, j, k, l) -> (a, b, c, d, e, f, g, h, i, j, k, l) -> Ordering # (<) :: (a, b, c, d, e, f, g, h, i, j, k, l) -> (a, b, c, d, e, f, g, h, i, j, k, l) -> Bool # (<=) :: (a, b, c, d, e, f, g, h, i, j, k, l) -> (a, b, c, d, e, f, g, h, i, j, k, l) -> Bool # (>) :: (a, b, c, d, e, f, g, h, i, j, k, l) -> (a, b, c, d, e, f, g, h, i, j, k, l) -> Bool # (>=) :: (a, b, c, d, e, f, g, h, i, j, k, l) -> (a, b, c, d, e, f, g, h, i, j, k, l) -> Bool # max :: (a, b, c, d, e, f, g, h, i, j, k, l) -> (a, b, c, d, e, f, g, h, i, j, k, l) -> (a, b, c, d, e, f, g, h, i, j, k, l) # min :: (a, b, c, d, e, f, g, h, i, j, k, l) -> (a, b, c, d, e, f, g, h, i, j, k, l) -> (a, b, c, d, e, f, g, h, i, j, k, l) # | |
(Ord a, Ord b, Ord c, Ord d, Ord e, Ord f, Ord g, Ord h, Ord i, Ord j, Ord k, Ord l, Ord m) => Ord (a, b, c, d, e, f, g, h, i, j, k, l, m) | |
Defined in GHC.Classes compare :: (a, b, c, d, e, f, g, h, i, j, k, l, m) -> (a, b, c, d, e, f, g, h, i, j, k, l, m) -> Ordering # (<) :: (a, b, c, d, e, f, g, h, i, j, k, l, m) -> (a, b, c, d, e, f, g, h, i, j, k, l, m) -> Bool # (<=) :: (a, b, c, d, e, f, g, h, i, j, k, l, m) -> (a, b, c, d, e, f, g, h, i, j, k, l, m) -> Bool # (>) :: (a, b, c, d, e, f, g, h, i, j, k, l, m) -> (a, b, c, d, e, f, g, h, i, j, k, l, m) -> Bool # (>=) :: (a, b, c, d, e, f, g, h, i, j, k, l, m) -> (a, b, c, d, e, f, g, h, i, j, k, l, m) -> Bool # max :: (a, b, c, d, e, f, g, h, i, j, k, l, m) -> (a, b, c, d, e, f, g, h, i, j, k, l, m) -> (a, b, c, d, e, f, g, h, i, j, k, l, m) # min :: (a, b, c, d, e, f, g, h, i, j, k, l, m) -> (a, b, c, d, e, f, g, h, i, j, k, l, m) -> (a, b, c, d, e, f, g, h, i, j, k, l, m) # | |
(Ord a, Ord b, Ord c, Ord d, Ord e, Ord f, Ord g, Ord h, Ord i, Ord j, Ord k, Ord l, Ord m, Ord n) => Ord (a, b, c, d, e, f, g, h, i, j, k, l, m, n) | |
Defined in GHC.Classes compare :: (a, b, c, d, e, f, g, h, i, j, k, l, m, n) -> (a, b, c, d, e, f, g, h, i, j, k, l, m, n) -> Ordering # (<) :: (a, b, c, d, e, f, g, h, i, j, k, l, m, n) -> (a, b, c, d, e, f, g, h, i, j, k, l, m, n) -> Bool # (<=) :: (a, b, c, d, e, f, g, h, i, j, k, l, m, n) -> (a, b, c, d, e, f, g, h, i, j, k, l, m, n) -> Bool # (>) :: (a, b, c, d, e, f, g, h, i, j, k, l, m, n) -> (a, b, c, d, e, f, g, h, i, j, k, l, m, n) -> Bool # (>=) :: (a, b, c, d, e, f, g, h, i, j, k, l, m, n) -> (a, b, c, d, e, f, g, h, i, j, k, l, m, n) -> Bool # max :: (a, b, c, d, e, f, g, h, i, j, k, l, m, n) -> (a, b, c, d, e, f, g, h, i, j, k, l, m, n) -> (a, b, c, d, e, f, g, h, i, j, k, l, m, n) # min :: (a, b, c, d, e, f, g, h, i, j, k, l, m, n) -> (a, b, c, d, e, f, g, h, i, j, k, l, m, n) -> (a, b, c, d, e, f, g, h, i, j, k, l, m, n) # | |
(Ord a, Ord b, Ord c, Ord d, Ord e, Ord f, Ord g, Ord h, Ord i, Ord j, Ord k, Ord l, Ord m, Ord n, Ord o) => Ord (a, b, c, d, e, f, g, h, i, j, k, l, m, n, o) | |
Defined in GHC.Classes 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) # |
comparing :: Ord a => (b -> a) -> b -> b -> Ordering #
comparing p x y = compare (p x) (p y)
Useful combinator for use in conjunction with the xxxBy
family
of functions from Data.List, for example:
... sortBy (comparing fst) ...
Enum
Class Enum
defines operations on sequentially ordered types.
The enumFrom
... methods are used in Haskell's translation of
arithmetic sequences.
Instances of Enum
may be derived for any enumeration type (types
whose constructors have no fields). The nullary constructors are
assumed to be numbered left-to-right by fromEnum
from 0
through n-1
.
See Chapter 10 of the Haskell Report for more details.
For any type that is an instance of class Bounded
as well as Enum
,
the following should hold:
- The calls
andsucc
maxBound
should result in a runtime error.pred
minBound
fromEnum
andtoEnum
should give a runtime error if the result value is not representable in the result type. For example,
is an error.toEnum
7 ::Bool
enumFrom
andenumFromThen
should be defined with an implicit bound, thus:
enumFrom x = enumFromTo x maxBound enumFromThen x y = enumFromThenTo x y bound where bound | fromEnum y >= fromEnum x = maxBound | otherwise = minBound
Convert to an Int
.
It is implementation-dependent what fromEnum
returns when
applied to a value that is too large to fit in an Int
.
Used in Haskell's translation of [n..]
.
enumFromThen :: a -> a -> [a] #
Used in Haskell's translation of [n,n'..]
.
enumFromTo :: a -> a -> [a] #
Used in Haskell's translation of [n..m]
.
enumFromThenTo :: a -> a -> a -> [a] #
Used in Haskell's translation of [n,n'..m]
.
Instances
Bounded
The Bounded
class is used to name the upper and lower limits of a
type. Ord
is not a superclass of Bounded
since types that are not
totally ordered may also have upper and lower bounds.
The Bounded
class may be derived for any enumeration type;
minBound
is the first constructor listed in the data
declaration
and maxBound
is the last.
Bounded
may also be derived for single-constructor datatypes whose
constituent types are in Bounded
.
Instances
Bounded Bool | Since: base-2.1 |
Bounded Char | Since: base-2.1 |
Bounded Int | Since: base-2.1 |
Bounded Int8 | Since: base-2.1 |
Bounded Int16 | Since: base-2.1 |
Bounded Int32 | Since: base-2.1 |
Bounded Int64 | Since: base-2.1 |
Bounded Ordering | Since: base-2.1 |
Bounded Word | Since: base-2.1 |
Bounded Word8 | Since: base-2.1 |
Bounded Word16 | Since: base-2.1 |
Bounded Word32 | Since: base-2.1 |
Bounded Word64 | Since: base-2.1 |
Bounded VecCount | Since: base-4.10.0.0 |
Bounded VecElem | Since: base-4.10.0.0 |
Bounded () | Since: base-2.1 |
Bounded All | |
Bounded Any | |
Bounded Associativity | |
Defined in GHC.Generics | |
Bounded SourceUnpackedness | |
Defined in GHC.Generics | |
Bounded SourceStrictness | |
Defined in GHC.Generics | |
Bounded DecidedStrictness | |
Defined in GHC.Generics | |
Bounded GeneralCategory | |
Defined in GHC.Unicode | |
Bounded a => Bounded (Min a) | |
Bounded a => Bounded (Max a) | |
Bounded a => Bounded (First a) | |
Bounded a => Bounded (Last a) | |
Bounded m => Bounded (WrappedMonoid m) | |
Defined in Data.Semigroup minBound :: WrappedMonoid m # maxBound :: WrappedMonoid m # | |
Bounded a => Bounded (Dual a) | |
Bounded a => Bounded (Sum a) | |
Bounded a => Bounded (Product a) | |
(Bounded a, Bounded b) => Bounded (a, b) | Since: base-2.1 |
(Bounded a, Bounded b, Bounded c) => Bounded (a, b, c) | Since: base-2.1 |
Bounded a => Bounded (Const a b) | |
(Bounded a, Bounded b, Bounded c, Bounded d) => Bounded (a, b, c, d) | Since: base-2.1 |
(Bounded a, Bounded b, Bounded c, Bounded d, Bounded e) => Bounded (a, b, c, d, e) | Since: base-2.1 |
(Bounded a, Bounded b, Bounded c, Bounded d, Bounded e, Bounded f) => Bounded (a, b, c, d, e, f) | Since: base-2.1 |
(Bounded a, Bounded b, Bounded c, Bounded d, Bounded e, Bounded f, Bounded g) => Bounded (a, b, c, d, e, f, g) | Since: base-2.1 |
(Bounded a, Bounded b, Bounded c, Bounded d, Bounded e, Bounded f, Bounded g, Bounded h) => Bounded (a, b, c, d, e, f, g, h) | Since: base-2.1 |
(Bounded a, Bounded b, Bounded c, Bounded d, Bounded e, Bounded f, Bounded g, Bounded h, Bounded i) => Bounded (a, b, c, d, e, f, g, h, i) | Since: base-2.1 |
(Bounded a, Bounded b, Bounded c, Bounded d, Bounded e, Bounded f, Bounded g, Bounded h, Bounded i, Bounded j) => Bounded (a, b, c, d, e, f, g, h, i, j) | Since: base-2.1 |
(Bounded a, Bounded b, Bounded c, Bounded d, Bounded e, Bounded f, Bounded g, Bounded h, Bounded i, Bounded j, Bounded k) => Bounded (a, b, c, d, e, f, g, h, i, j, k) | Since: base-2.1 |
(Bounded a, Bounded b, Bounded c, Bounded d, Bounded e, Bounded f, Bounded g, Bounded h, Bounded i, Bounded j, Bounded k, Bounded l) => Bounded (a, b, c, d, e, f, g, h, i, j, k, l) | Since: base-2.1 |
(Bounded a, Bounded b, Bounded c, Bounded d, Bounded e, Bounded f, Bounded g, Bounded h, Bounded i, Bounded j, Bounded k, Bounded l, Bounded m) => Bounded (a, b, c, d, e, f, g, h, i, j, k, l, m) | Since: base-2.1 |
(Bounded a, Bounded b, Bounded c, Bounded d, Bounded e, Bounded f, Bounded g, Bounded h, Bounded i, Bounded j, Bounded k, Bounded l, Bounded m, Bounded n) => Bounded (a, b, c, d, e, f, g, h, i, j, k, l, m, n) | Since: base-2.1 |
(Bounded a, Bounded b, Bounded c, Bounded d, Bounded e, Bounded f, Bounded g, Bounded h, Bounded i, Bounded j, Bounded k, Bounded l, Bounded m, Bounded n, Bounded o) => Bounded (a, b, c, d, e, f, g, h, i, j, k, l, m, n, o) | Since: base-2.1 |
2-tuples
uncurry :: (a -> b -> c) -> (a, b) -> c #
uncurry
converts a curried function to a function on pairs.
Examples
>>>
uncurry (+) (1,2)
3
>>>
uncurry ($) (show, 1)
"1"
>>>
map (uncurry max) [(1,2), (3,4), (6,8)]
[2,4,8]
Num
eric types, classes, and helpers
Invariant: Jn#
and Jp#
are used iff value doesn't fit in S#
Useful properties resulting from the invariants:
Instances
Enum Integer | Since: base-2.1 |
Eq Integer | |
Integral Integer | Since: base-2.0.1 |
Defined in GHC.Real | |
Data Integer | Since: base-4.0.0.0 |
Defined in Data.Data gfoldl :: (forall d b. Data d => c (d -> b) -> d -> c b) -> (forall g. g -> c g) -> Integer -> c Integer # gunfold :: (forall b r. Data b => c (b -> r) -> c r) -> (forall r. r -> c r) -> Constr -> c Integer # toConstr :: Integer -> Constr # dataTypeOf :: Integer -> DataType # dataCast1 :: Typeable t => (forall d. Data d => c (t d)) -> Maybe (c Integer) # dataCast2 :: Typeable t => (forall d e. (Data d, Data e) => c (t d e)) -> Maybe (c Integer) # gmapT :: (forall b. Data b => b -> b) -> Integer -> Integer # gmapQl :: (r -> r' -> r) -> r -> (forall d. Data d => d -> r') -> Integer -> r # gmapQr :: (r' -> r -> r) -> r -> (forall d. Data d => d -> r') -> Integer -> r # gmapQ :: (forall d. Data d => d -> u) -> Integer -> [u] # gmapQi :: Int -> (forall d. Data d => d -> u) -> Integer -> u # gmapM :: Monad m => (forall d. Data d => d -> m d) -> Integer -> m Integer # gmapMp :: MonadPlus m => (forall d. Data d => d -> m d) -> Integer -> m Integer # gmapMo :: MonadPlus m => (forall d. Data d => d -> m d) -> Integer -> m Integer # | |
Num Integer | Since: base-2.1 |
Ord Integer | |
Read Integer | Since: base-2.1 |
Real Integer | Since: base-2.0.1 |
Defined in GHC.Real toRational :: Integer -> Rational # | |
Show Integer | Since: base-2.1 |
Ix Integer | Since: base-2.1 |
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
Bounded Int | Since: base-2.1 |
Enum Int | Since: base-2.1 |
Eq Int | |
Integral Int | Since: base-2.0.1 |
Data Int | Since: base-4.0.0.0 |
Defined in Data.Data gfoldl :: (forall d b. Data d => c (d -> b) -> d -> c b) -> (forall g. g -> c g) -> Int -> c Int # gunfold :: (forall b r. Data b => c (b -> r) -> c r) -> (forall r. r -> c r) -> Constr -> c Int # dataTypeOf :: Int -> DataType # dataCast1 :: Typeable t => (forall d. Data d => c (t d)) -> Maybe (c Int) # dataCast2 :: Typeable t => (forall d e. (Data d, Data e) => c (t d e)) -> Maybe (c Int) # gmapT :: (forall b. Data b => b -> b) -> Int -> Int # gmapQl :: (r -> r' -> r) -> r -> (forall d. Data d => d -> r') -> Int -> r # gmapQr :: (r' -> r -> r) -> r -> (forall d. Data d => d -> r') -> Int -> r # gmapQ :: (forall d. Data d => d -> u) -> Int -> [u] # gmapQi :: Int -> (forall d. Data d => d -> u) -> Int -> u # gmapM :: Monad m => (forall d. Data d => d -> m d) -> Int -> m Int # gmapMp :: MonadPlus m => (forall d. Data d => d -> m d) -> Int -> m Int # gmapMo :: MonadPlus m => (forall d. Data d => d -> m d) -> Int -> m Int # | |
Num Int | Since: base-2.1 |
Ord Int | |
Read Int | Since: base-2.1 |
Real Int | Since: base-2.0.1 |
Defined in GHC.Real toRational :: Int -> Rational # | |
Show Int | Since: base-2.1 |
Ix Int | Since: base-2.1 |
Generic1 (URec Int :: k -> *) | |
Functor (URec Int :: * -> *) | |
Foldable (URec Int :: * -> *) | |
Defined in Data.Foldable fold :: Monoid m => URec Int m -> m # foldMap :: Monoid m => (a -> m) -> URec Int a -> m # foldr :: (a -> b -> b) -> b -> URec Int a -> b # foldr' :: (a -> b -> b) -> b -> URec Int a -> b # foldl :: (b -> a -> b) -> b -> URec Int a -> b # foldl' :: (b -> a -> b) -> b -> URec Int a -> b # foldr1 :: (a -> a -> a) -> URec Int a -> a # foldl1 :: (a -> a -> a) -> URec Int a -> a # elem :: Eq a => a -> URec Int a -> Bool # maximum :: Ord a => URec Int a -> a # minimum :: Ord a => URec Int a -> a # | |
Traversable (URec Int :: * -> *) | |
Eq (URec Int p) | |
Ord (URec Int p) | |
Show (URec Int p) | |
Generic (URec Int p) | |
data URec Int (p :: k) | Used for marking occurrences of Since: base-4.9.0.0 |
type Rep1 (URec Int :: k -> *) | |
Defined in GHC.Generics | |
type Rep (URec Int p) | |
Defined in GHC.Generics |
8-bit signed integer type
Instances
Bounded Int8 | Since: base-2.1 |
Enum Int8 | Since: base-2.1 |
Eq Int8 | Since: base-2.1 |
Integral Int8 | Since: base-2.1 |
Data Int8 | Since: base-4.0.0.0 |
Defined in Data.Data gfoldl :: (forall d b. Data d => c (d -> b) -> d -> c b) -> (forall g. g -> c g) -> Int8 -> c Int8 # gunfold :: (forall b r. Data b => c (b -> r) -> c r) -> (forall r. r -> c r) -> Constr -> c Int8 # dataTypeOf :: Int8 -> DataType # dataCast1 :: Typeable t => (forall d. Data d => c (t d)) -> Maybe (c Int8) # dataCast2 :: Typeable t => (forall d e. (Data d, Data e) => c (t d e)) -> Maybe (c Int8) # gmapT :: (forall b. Data b => b -> b) -> Int8 -> Int8 # gmapQl :: (r -> r' -> r) -> r -> (forall d. Data d => d -> r') -> Int8 -> r # gmapQr :: (r' -> r -> r) -> r -> (forall d. Data d => d -> r') -> Int8 -> r # gmapQ :: (forall d. Data d => d -> u) -> Int8 -> [u] # gmapQi :: Int -> (forall d. Data d => d -> u) -> Int8 -> u # gmapM :: Monad m => (forall d. Data d => d -> m d) -> Int8 -> m Int8 # gmapMp :: MonadPlus m => (forall d. Data d => d -> m d) -> Int8 -> m Int8 # gmapMo :: MonadPlus m => (forall d. Data d => d -> m d) -> Int8 -> m Int8 # | |
Num Int8 | Since: base-2.1 |
Ord Int8 | Since: base-2.1 |
Read Int8 | Since: base-2.1 |
Real Int8 | Since: base-2.1 |
Defined in GHC.Int toRational :: Int8 -> Rational # | |
Show Int8 | Since: base-2.1 |
Ix Int8 | Since: base-2.1 |
Bits Int8 | Since: base-2.1 |
Defined in GHC.Int (.&.) :: Int8 -> Int8 -> Int8 # (.|.) :: Int8 -> Int8 -> Int8 # complement :: Int8 -> Int8 # shift :: Int8 -> Int -> Int8 # rotate :: Int8 -> Int -> Int8 # setBit :: Int8 -> Int -> Int8 # clearBit :: Int8 -> Int -> Int8 # complementBit :: Int8 -> Int -> Int8 # testBit :: Int8 -> Int -> Bool # bitSizeMaybe :: Int8 -> Maybe Int # shiftL :: Int8 -> Int -> Int8 # unsafeShiftL :: Int8 -> Int -> Int8 # shiftR :: Int8 -> Int -> Int8 # unsafeShiftR :: Int8 -> Int -> Int8 # rotateL :: Int8 -> Int -> Int8 # | |
FiniteBits Int8 | Since: base-4.6.0.0 |
Defined in GHC.Int |
16-bit signed integer type
Instances
Bounded Int16 | Since: base-2.1 |
Enum Int16 | Since: base-2.1 |
Eq Int16 | Since: base-2.1 |
Integral Int16 | Since: base-2.1 |
Data Int16 | Since: base-4.0.0.0 |
Defined in Data.Data gfoldl :: (forall d b. Data d => c (d -> b) -> d -> c b) -> (forall g. g -> c g) -> Int16 -> c Int16 # gunfold :: (forall b r. Data b => c (b -> r) -> c r) -> (forall r. r -> c r) -> Constr -> c Int16 # dataTypeOf :: Int16 -> DataType # dataCast1 :: Typeable t => (forall d. Data d => c (t d)) -> Maybe (c Int16) # dataCast2 :: Typeable t => (forall d e. (Data d, Data e) => c (t d e)) -> Maybe (c Int16) # gmapT :: (forall b. Data b => b -> b) -> Int16 -> Int16 # gmapQl :: (r -> r' -> r) -> r -> (forall d. Data d => d -> r') -> Int16 -> r # gmapQr :: (r' -> r -> r) -> r -> (forall d. Data d => d -> r') -> Int16 -> r # gmapQ :: (forall d. Data d => d -> u) -> Int16 -> [u] # gmapQi :: Int -> (forall d. Data d => d -> u) -> Int16 -> u # gmapM :: Monad m => (forall d. Data d => d -> m d) -> Int16 -> m Int16 # gmapMp :: MonadPlus m => (forall d. Data d => d -> m d) -> Int16 -> m Int16 # gmapMo :: MonadPlus m => (forall d. Data d => d -> m d) -> Int16 -> m Int16 # | |
Num Int16 | Since: base-2.1 |
Ord Int16 | Since: base-2.1 |
Read Int16 | Since: base-2.1 |
Real Int16 | Since: base-2.1 |
Defined in GHC.Int toRational :: Int16 -> Rational # | |
Show Int16 | Since: base-2.1 |
Ix Int16 | Since: base-2.1 |
Bits Int16 | Since: base-2.1 |
Defined in GHC.Int (.&.) :: Int16 -> Int16 -> Int16 # (.|.) :: Int16 -> Int16 -> Int16 # xor :: Int16 -> Int16 -> Int16 # complement :: Int16 -> Int16 # shift :: Int16 -> Int -> Int16 # rotate :: Int16 -> Int -> Int16 # setBit :: Int16 -> Int -> Int16 # clearBit :: Int16 -> Int -> Int16 # complementBit :: Int16 -> Int -> Int16 # testBit :: Int16 -> Int -> Bool # bitSizeMaybe :: Int16 -> Maybe Int # shiftL :: Int16 -> Int -> Int16 # unsafeShiftL :: Int16 -> Int -> Int16 # shiftR :: Int16 -> Int -> Int16 # unsafeShiftR :: Int16 -> Int -> Int16 # rotateL :: Int16 -> Int -> Int16 # | |
FiniteBits Int16 | Since: base-4.6.0.0 |
Defined in GHC.Int finiteBitSize :: Int16 -> Int # countLeadingZeros :: Int16 -> Int # countTrailingZeros :: Int16 -> Int # |
32-bit signed integer type
Instances
Bounded Int32 | Since: base-2.1 |
Enum Int32 | Since: base-2.1 |
Eq Int32 | Since: base-2.1 |
Integral Int32 | Since: base-2.1 |
Data Int32 | Since: base-4.0.0.0 |
Defined in Data.Data gfoldl :: (forall d b. Data d => c (d -> b) -> d -> c b) -> (forall g. g -> c g) -> Int32 -> c Int32 # gunfold :: (forall b r. Data b => c (b -> r) -> c r) -> (forall r. r -> c r) -> Constr -> c Int32 # dataTypeOf :: Int32 -> DataType # dataCast1 :: Typeable t => (forall d. Data d => c (t d)) -> Maybe (c Int32) # dataCast2 :: Typeable t => (forall d e. (Data d, Data e) => c (t d e)) -> Maybe (c Int32) # gmapT :: (forall b. Data b => b -> b) -> Int32 -> Int32 # gmapQl :: (r -> r' -> r) -> r -> (forall d. Data d => d -> r') -> Int32 -> r # gmapQr :: (r' -> r -> r) -> r -> (forall d. Data d => d -> r') -> Int32 -> r # gmapQ :: (forall d. Data d => d -> u) -> Int32 -> [u] # gmapQi :: Int -> (forall d. Data d => d -> u) -> Int32 -> u # gmapM :: Monad m => (forall d. Data d => d -> m d) -> Int32 -> m Int32 # gmapMp :: MonadPlus m => (forall d. Data d => d -> m d) -> Int32 -> m Int32 # gmapMo :: MonadPlus m => (forall d. Data d => d -> m d) -> Int32 -> m Int32 # | |
Num Int32 | Since: base-2.1 |
Ord Int32 | Since: base-2.1 |
Read Int32 | Since: base-2.1 |
Real Int32 | Since: base-2.1 |
Defined in GHC.Int toRational :: Int32 -> Rational # | |
Show Int32 | Since: base-2.1 |
Ix Int32 | Since: base-2.1 |
Bits Int32 | Since: base-2.1 |
Defined in GHC.Int (.&.) :: Int32 -> Int32 -> Int32 # (.|.) :: Int32 -> Int32 -> Int32 # xor :: Int32 -> Int32 -> Int32 # complement :: Int32 -> Int32 # shift :: Int32 -> Int -> Int32 # rotate :: Int32 -> Int -> Int32 # setBit :: Int32 -> Int -> Int32 # clearBit :: Int32 -> Int -> Int32 # complementBit :: Int32 -> Int -> Int32 # testBit :: Int32 -> Int -> Bool # bitSizeMaybe :: Int32 -> Maybe Int # shiftL :: Int32 -> Int -> Int32 # unsafeShiftL :: Int32 -> Int -> Int32 # shiftR :: Int32 -> Int -> Int32 # unsafeShiftR :: Int32 -> Int -> Int32 # rotateL :: Int32 -> Int -> Int32 # | |
FiniteBits Int32 | Since: base-4.6.0.0 |
Defined in GHC.Int finiteBitSize :: Int32 -> Int # countLeadingZeros :: Int32 -> Int # countTrailingZeros :: Int32 -> Int # |
64-bit signed integer type
Instances
Bounded Int64 | Since: base-2.1 |
Enum Int64 | Since: base-2.1 |
Eq Int64 | Since: base-2.1 |
Integral Int64 | Since: base-2.1 |
Data Int64 | Since: base-4.0.0.0 |
Defined in Data.Data gfoldl :: (forall d b. Data d => c (d -> b) -> d -> c b) -> (forall g. g -> c g) -> Int64 -> c Int64 # gunfold :: (forall b r. Data b => c (b -> r) -> c r) -> (forall r. r -> c r) -> Constr -> c Int64 # dataTypeOf :: Int64 -> DataType # dataCast1 :: Typeable t => (forall d. Data d => c (t d)) -> Maybe (c Int64) # dataCast2 :: Typeable t => (forall d e. (Data d, Data e) => c (t d e)) -> Maybe (c Int64) # gmapT :: (forall b. Data b => b -> b) -> Int64 -> Int64 # gmapQl :: (r -> r' -> r) -> r -> (forall d. Data d => d -> r') -> Int64 -> r # gmapQr :: (r' -> r -> r) -> r -> (forall d. Data d => d -> r') -> Int64 -> r # gmapQ :: (forall d. Data d => d -> u) -> Int64 -> [u] # gmapQi :: Int -> (forall d. Data d => d -> u) -> Int64 -> u # gmapM :: Monad m => (forall d. Data d => d -> m d) -> Int64 -> m Int64 # gmapMp :: MonadPlus m => (forall d. Data d => d -> m d) -> Int64 -> m Int64 # gmapMo :: MonadPlus m => (forall d. Data d => d -> m d) -> Int64 -> m Int64 # | |
Num Int64 | Since: base-2.1 |
Ord Int64 | Since: base-2.1 |
Read Int64 | Since: base-2.1 |
Real Int64 | Since: base-2.1 |
Defined in GHC.Int toRational :: Int64 -> Rational # | |
Show Int64 | Since: base-2.1 |
Ix Int64 | Since: base-2.1 |
Bits Int64 | Since: base-2.1 |
Defined in GHC.Int (.&.) :: Int64 -> Int64 -> Int64 # (.|.) :: Int64 -> Int64 -> Int64 # xor :: Int64 -> Int64 -> Int64 # complement :: Int64 -> Int64 # shift :: Int64 -> Int -> Int64 # rotate :: Int64 -> Int -> Int64 # setBit :: Int64 -> Int -> Int64 # clearBit :: Int64 -> Int -> Int64 # complementBit :: Int64 -> Int -> Int64 # testBit :: Int64 -> Int -> Bool # bitSizeMaybe :: Int64 -> Maybe Int # shiftL :: Int64 -> Int -> Int64 # unsafeShiftL :: Int64 -> Int -> Int64 # shiftR :: Int64 -> Int -> Int64 # unsafeShiftR :: Int64 -> Int -> Int64 # rotateL :: Int64 -> Int -> Int64 # | |
FiniteBits Int64 | Since: base-4.6.0.0 |
Defined in GHC.Int finiteBitSize :: Int64 -> Int # countLeadingZeros :: Int64 -> Int # countTrailingZeros :: Int64 -> Int # |
Instances
Bounded Word | Since: base-2.1 |
Enum Word | Since: base-2.1 |
Eq Word | |
Integral Word | Since: base-2.1 |
Data Word | Since: base-4.0.0.0 |
Defined in Data.Data gfoldl :: (forall d b. Data d => c (d -> b) -> d -> c b) -> (forall g. g -> c g) -> Word -> c Word # gunfold :: (forall b r. Data b => c (b -> r) -> c r) -> (forall r. r -> c r) -> Constr -> c Word # dataTypeOf :: Word -> DataType # dataCast1 :: Typeable t => (forall d. Data d => c (t d)) -> Maybe (c Word) # dataCast2 :: Typeable t => (forall d e. (Data d, Data e) => c (t d e)) -> Maybe (c Word) # gmapT :: (forall b. Data b => b -> b) -> Word -> Word # gmapQl :: (r -> r' -> r) -> r -> (forall d. Data d => d -> r') -> Word -> r # gmapQr :: (r' -> r -> r) -> r -> (forall d. Data d => d -> r') -> Word -> r # gmapQ :: (forall d. Data d => d -> u) -> Word -> [u] # gmapQi :: Int -> (forall d. Data d => d -> u) -> Word -> u # gmapM :: Monad m => (forall d. Data d => d -> m d) -> Word -> m Word # gmapMp :: MonadPlus m => (forall d. Data d => d -> m d) -> Word -> m Word # gmapMo :: MonadPlus m => (forall d. Data d => d -> m d) -> Word -> m Word # | |
Num Word | Since: base-2.1 |
Ord Word | |
Read Word | Since: base-4.5.0.0 |
Real Word | Since: base-2.1 |
Defined in GHC.Real toRational :: Word -> Rational # | |
Show Word | Since: base-2.1 |
Ix Word | Since: base-4.6.0.0 |
Generic1 (URec Word :: k -> *) | |
Functor (URec Word :: * -> *) | |
Foldable (URec Word :: * -> *) | |
Defined in Data.Foldable fold :: Monoid m => URec Word m -> m # foldMap :: Monoid m => (a -> m) -> URec Word a -> m # foldr :: (a -> b -> b) -> b -> URec Word a -> b # foldr' :: (a -> b -> b) -> b -> URec Word a -> b # foldl :: (b -> a -> b) -> b -> URec Word a -> b # foldl' :: (b -> a -> b) -> b -> URec Word a -> b # foldr1 :: (a -> a -> a) -> URec Word a -> a # foldl1 :: (a -> a -> a) -> URec Word a -> a # toList :: URec Word a -> [a] # length :: URec Word a -> Int # elem :: Eq a => a -> URec Word a -> Bool # maximum :: Ord a => URec Word a -> a # minimum :: Ord a => URec Word a -> a # | |
Traversable (URec Word :: * -> *) | |
Eq (URec Word p) | |
Ord (URec Word p) | |
Show (URec Word p) | |
Generic (URec Word p) | |
data URec Word (p :: k) | Used for marking occurrences of Since: base-4.9.0.0 |
type Rep1 (URec Word :: k -> *) | |
Defined in GHC.Generics | |
type Rep (URec Word p) | |
Defined in GHC.Generics |
8-bit unsigned integer type
Instances
Bounded Word8 | Since: base-2.1 |
Enum Word8 | Since: base-2.1 |
Eq Word8 | Since: base-2.1 |
Integral Word8 | Since: base-2.1 |
Data Word8 | Since: base-4.0.0.0 |
Defined in Data.Data gfoldl :: (forall d b. Data d => c (d -> b) -> d -> c b) -> (forall g. g -> c g) -> Word8 -> c Word8 # gunfold :: (forall b r. Data b => c (b -> r) -> c r) -> (forall r. r -> c r) -> Constr -> c Word8 # dataTypeOf :: Word8 -> DataType # dataCast1 :: Typeable t => (forall d. Data d => c (t d)) -> Maybe (c Word8) # dataCast2 :: Typeable t => (forall d e. (Data d, Data e) => c (t d e)) -> Maybe (c Word8) # gmapT :: (forall b. Data b => b -> b) -> Word8 -> Word8 # gmapQl :: (r -> r' -> r) -> r -> (forall d. Data d => d -> r') -> Word8 -> r # gmapQr :: (r' -> r -> r) -> r -> (forall d. Data d => d -> r') -> Word8 -> r # gmapQ :: (forall d. Data d => d -> u) -> Word8 -> [u] # gmapQi :: Int -> (forall d. Data d => d -> u) -> Word8 -> u # gmapM :: Monad m => (forall d. Data d => d -> m d) -> Word8 -> m Word8 # gmapMp :: MonadPlus m => (forall d. Data d => d -> m d) -> Word8 -> m Word8 # gmapMo :: MonadPlus m => (forall d. Data d => d -> m d) -> Word8 -> m Word8 # | |
Num Word8 | Since: base-2.1 |
Ord Word8 | Since: base-2.1 |
Read Word8 | Since: base-2.1 |
Real Word8 | Since: base-2.1 |
Defined in GHC.Word toRational :: Word8 -> Rational # | |
Show Word8 | Since: base-2.1 |
Ix Word8 | Since: base-2.1 |
Bits Word8 | Since: base-2.1 |
Defined in GHC.Word (.&.) :: Word8 -> Word8 -> Word8 # (.|.) :: Word8 -> Word8 -> Word8 # xor :: Word8 -> Word8 -> Word8 # complement :: Word8 -> Word8 # shift :: Word8 -> Int -> Word8 # rotate :: Word8 -> Int -> Word8 # setBit :: Word8 -> Int -> Word8 # clearBit :: Word8 -> Int -> Word8 # complementBit :: Word8 -> Int -> Word8 # testBit :: Word8 -> Int -> Bool # bitSizeMaybe :: Word8 -> Maybe Int # shiftL :: Word8 -> Int -> Word8 # unsafeShiftL :: Word8 -> Int -> Word8 # shiftR :: Word8 -> Int -> Word8 # unsafeShiftR :: Word8 -> Int -> Word8 # rotateL :: Word8 -> Int -> Word8 # | |
FiniteBits Word8 | Since: base-4.6.0.0 |
Defined in GHC.Word finiteBitSize :: Word8 -> Int # countLeadingZeros :: Word8 -> Int # countTrailingZeros :: Word8 -> Int # |
16-bit unsigned integer type
Instances
Bounded Word16 | Since: base-2.1 |
Enum Word16 | Since: base-2.1 |
Defined in GHC.Word | |
Eq Word16 | Since: base-2.1 |
Integral Word16 | Since: base-2.1 |
Data Word16 | Since: base-4.0.0.0 |
Defined in Data.Data gfoldl :: (forall d b. Data d => c (d -> b) -> d -> c b) -> (forall g. g -> c g) -> Word16 -> c Word16 # gunfold :: (forall b r. Data b => c (b -> r) -> c r) -> (forall r. r -> c r) -> Constr -> c Word16 # toConstr :: Word16 -> Constr # dataTypeOf :: Word16 -> DataType # dataCast1 :: Typeable t => (forall d. Data d => c (t d)) -> Maybe (c Word16) # dataCast2 :: Typeable t => (forall d e. (Data d, Data e) => c (t d e)) -> Maybe (c Word16) # gmapT :: (forall b. Data b => b -> b) -> Word16 -> Word16 # gmapQl :: (r -> r' -> r) -> r -> (forall d. Data d => d -> r') -> Word16 -> r # gmapQr :: (r' -> r -> r) -> r -> (forall d. Data d => d -> r') -> Word16 -> r # gmapQ :: (forall d. Data d => d -> u) -> Word16 -> [u] # gmapQi :: Int -> (forall d. Data d => d -> u) -> Word16 -> u # gmapM :: Monad m => (forall d. Data d => d -> m d) -> Word16 -> m Word16 # gmapMp :: MonadPlus m => (forall d. Data d => d -> m d) -> Word16 -> m Word16 # gmapMo :: MonadPlus m => (forall d. Data d => d -> m d) -> Word16 -> m Word16 # | |
Num Word16 | Since: base-2.1 |
Ord Word16 | Since: base-2.1 |
Read Word16 | Since: base-2.1 |
Real Word16 | Since: base-2.1 |
Defined in GHC.Word toRational :: Word16 -> Rational # | |
Show Word16 | Since: base-2.1 |
Ix Word16 | Since: base-2.1 |
Bits Word16 | Since: base-2.1 |
Defined in GHC.Word (.&.) :: Word16 -> Word16 -> Word16 # (.|.) :: Word16 -> Word16 -> Word16 # xor :: Word16 -> Word16 -> Word16 # complement :: Word16 -> Word16 # shift :: Word16 -> Int -> Word16 # rotate :: Word16 -> Int -> Word16 # setBit :: Word16 -> Int -> Word16 # clearBit :: Word16 -> Int -> Word16 # complementBit :: Word16 -> Int -> Word16 # testBit :: Word16 -> Int -> Bool # bitSizeMaybe :: Word16 -> Maybe Int # shiftL :: Word16 -> Int -> Word16 # unsafeShiftL :: Word16 -> Int -> Word16 # shiftR :: Word16 -> Int -> Word16 # unsafeShiftR :: Word16 -> Int -> Word16 # rotateL :: Word16 -> Int -> Word16 # | |
FiniteBits Word16 | Since: base-4.6.0.0 |
Defined in GHC.Word finiteBitSize :: Word16 -> Int # countLeadingZeros :: Word16 -> Int # countTrailingZeros :: Word16 -> Int # |
32-bit unsigned integer type
Instances
Bounded Word32 | Since: base-2.1 |
Enum Word32 | Since: base-2.1 |
Defined in GHC.Word | |
Eq Word32 | Since: base-2.1 |
Integral Word32 | Since: base-2.1 |
Data Word32 | Since: base-4.0.0.0 |
Defined in Data.Data gfoldl :: (forall d b. Data d => c (d -> b) -> d -> c b) -> (forall g. g -> c g) -> Word32 -> c Word32 # gunfold :: (forall b r. Data b => c (b -> r) -> c r) -> (forall r. r -> c r) -> Constr -> c Word32 # toConstr :: Word32 -> Constr # dataTypeOf :: Word32 -> DataType # dataCast1 :: Typeable t => (forall d. Data d => c (t d)) -> Maybe (c Word32) # dataCast2 :: Typeable t => (forall d e. (Data d, Data e) => c (t d e)) -> Maybe (c Word32) # gmapT :: (forall b. Data b => b -> b) -> Word32 -> Word32 # gmapQl :: (r -> r' -> r) -> r -> (forall d. Data d => d -> r') -> Word32 -> r # gmapQr :: (r' -> r -> r) -> r -> (forall d. Data d => d -> r') -> Word32 -> r # gmapQ :: (forall d. Data d => d -> u) -> Word32 -> [u] # gmapQi :: Int -> (forall d. Data d => d -> u) -> Word32 -> u # gmapM :: Monad m => (forall d. Data d => d -> m d) -> Word32 -> m Word32 # gmapMp :: MonadPlus m => (forall d. Data d => d -> m d) -> Word32 -> m Word32 # gmapMo :: MonadPlus m => (forall d. Data d => d -> m d) -> Word32 -> m Word32 # | |
Num Word32 | Since: base-2.1 |
Ord Word32 | Since: base-2.1 |
Read Word32 | Since: base-2.1 |
Real Word32 | Since: base-2.1 |
Defined in GHC.Word toRational :: Word32 -> Rational # | |
Show Word32 | Since: base-2.1 |
Ix Word32 | Since: base-2.1 |
Bits Word32 | Since: base-2.1 |
Defined in GHC.Word (.&.) :: Word32 -> Word32 -> Word32 # (.|.) :: Word32 -> Word32 -> Word32 # xor :: Word32 -> Word32 -> Word32 # complement :: Word32 -> Word32 # shift :: Word32 -> Int -> Word32 # rotate :: Word32 -> Int -> Word32 # setBit :: Word32 -> Int -> Word32 # clearBit :: Word32 -> Int -> Word32 # complementBit :: Word32 -> Int -> Word32 # testBit :: Word32 -> Int -> Bool # bitSizeMaybe :: Word32 -> Maybe Int # shiftL :: Word32 -> Int -> Word32 # unsafeShiftL :: Word32 -> Int -> Word32 # shiftR :: Word32 -> Int -> Word32 # unsafeShiftR :: Word32 -> Int -> Word32 # rotateL :: Word32 -> Int -> Word32 # | |
FiniteBits Word32 | Since: base-4.6.0.0 |
Defined in GHC.Word finiteBitSize :: Word32 -> Int # countLeadingZeros :: Word32 -> Int # countTrailingZeros :: Word32 -> Int # |
64-bit unsigned integer type
Instances
Bounded Word64 | Since: base-2.1 |
Enum Word64 | Since: base-2.1 |
Defined in GHC.Word | |
Eq Word64 | Since: base-2.1 |
Integral Word64 | Since: base-2.1 |
Data Word64 | Since: base-4.0.0.0 |
Defined in Data.Data gfoldl :: (forall d b. Data d => c (d -> b) -> d -> c b) -> (forall g. g -> c g) -> Word64 -> c Word64 # gunfold :: (forall b r. Data b => c (b -> r) -> c r) -> (forall r. r -> c r) -> Constr -> c Word64 # toConstr :: Word64 -> Constr # dataTypeOf :: Word64 -> DataType # dataCast1 :: Typeable t => (forall d. Data d => c (t d)) -> Maybe (c Word64) # dataCast2 :: Typeable t => (forall d e. (Data d, Data e) => c (t d e)) -> Maybe (c Word64) # gmapT :: (forall b. Data b => b -> b) -> Word64 -> Word64 # gmapQl :: (r -> r' -> r) -> r -> (forall d. Data d => d -> r') -> Word64 -> r # gmapQr :: (r' -> r -> r) -> r -> (forall d. Data d => d -> r') -> Word64 -> r # gmapQ :: (forall d. Data d => d -> u) -> Word64 -> [u] # gmapQi :: Int -> (forall d. Data d => d -> u) -> Word64 -> u # gmapM :: Monad m => (forall d. Data d => d -> m d) -> Word64 -> m Word64 # gmapMp :: MonadPlus m => (forall d. Data d => d -> m d) -> Word64 -> m Word64 # gmapMo :: MonadPlus m => (forall d. Data d => d -> m d) -> Word64 -> m Word64 # | |
Num Word64 | Since: base-2.1 |
Ord Word64 | Since: base-2.1 |
Read Word64 | Since: base-2.1 |
Real Word64 | Since: base-2.1 |
Defined in GHC.Word toRational :: Word64 -> Rational # | |
Show Word64 | Since: base-2.1 |
Ix Word64 | Since: base-2.1 |
Bits Word64 | Since: base-2.1 |
Defined in GHC.Word (.&.) :: Word64 -> Word64 -> Word64 # (.|.) :: Word64 -> Word64 -> Word64 # xor :: Word64 -> Word64 -> Word64 # complement :: Word64 -> Word64 # shift :: Word64 -> Int -> Word64 # rotate :: Word64 -> Int -> Word64 # setBit :: Word64 -> Int -> Word64 # clearBit :: Word64 -> Int -> Word64 # complementBit :: Word64 -> Int -> Word64 # testBit :: Word64 -> Int -> Bool # bitSizeMaybe :: Word64 -> Maybe Int # shiftL :: Word64 -> Int -> Word64 # unsafeShiftL :: Word64 -> Int -> Word64 # shiftR :: Word64 -> Int -> Word64 # unsafeShiftR :: Word64 -> Int -> Word64 # rotateL :: Word64 -> Int -> Word64 # | |
FiniteBits Word64 | Since: base-4.6.0.0 |
Defined in GHC.Word finiteBitSize :: Word64 -> Int # countLeadingZeros :: Word64 -> Int # countTrailingZeros :: Word64 -> Int # |
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
Eq Float | |
Floating Float | Since: base-2.1 |
Data Float | Since: base-4.0.0.0 |
Defined in Data.Data gfoldl :: (forall d b. Data d => c (d -> b) -> d -> c b) -> (forall g. g -> c g) -> Float -> c Float # gunfold :: (forall b r. Data b => c (b -> r) -> c r) -> (forall r. r -> c r) -> Constr -> c Float # dataTypeOf :: Float -> DataType # dataCast1 :: Typeable t => (forall d. Data d => c (t d)) -> Maybe (c Float) # dataCast2 :: Typeable t => (forall d e. (Data d, Data e) => c (t d e)) -> Maybe (c Float) # gmapT :: (forall b. Data b => b -> b) -> Float -> Float # gmapQl :: (r -> r' -> r) -> r -> (forall d. Data d => d -> r') -> Float -> r # gmapQr :: (r' -> r -> r) -> r -> (forall d. Data d => d -> r') -> Float -> r # gmapQ :: (forall d. Data d => d -> u) -> Float -> [u] # gmapQi :: Int -> (forall d. Data d => d -> u) -> Float -> u # gmapM :: Monad m => (forall d. Data d => d -> m d) -> Float -> m Float # gmapMp :: MonadPlus m => (forall d. Data d => d -> m d) -> Float -> m Float # gmapMo :: MonadPlus m => (forall d. Data d => d -> m d) -> Float -> m Float # | |
Ord Float | |
Read Float | Since: base-2.1 |
RealFloat Float | Since: base-2.1 |
Defined in GHC.Float floatRadix :: Float -> Integer # floatDigits :: Float -> Int # floatRange :: Float -> (Int, Int) # decodeFloat :: Float -> (Integer, Int) # encodeFloat :: Integer -> Int -> Float # significand :: Float -> Float # scaleFloat :: Int -> Float -> Float # isInfinite :: Float -> Bool # isDenormalized :: Float -> Bool # isNegativeZero :: Float -> Bool # | |
Generic1 (URec Float :: k -> *) | |
Functor (URec Float :: * -> *) | |
Foldable (URec Float :: * -> *) | |
Defined in Data.Foldable fold :: Monoid m => URec Float m -> m # foldMap :: Monoid m => (a -> m) -> URec Float a -> m # foldr :: (a -> b -> b) -> b -> URec Float a -> b # foldr' :: (a -> b -> b) -> b -> URec Float a -> b # foldl :: (b -> a -> b) -> b -> URec Float a -> b # foldl' :: (b -> a -> b) -> b -> URec Float a -> b # foldr1 :: (a -> a -> a) -> URec Float a -> a # foldl1 :: (a -> a -> a) -> URec Float a -> a # toList :: URec Float a -> [a] # null :: URec Float a -> Bool # length :: URec Float a -> Int # elem :: Eq a => a -> URec Float a -> Bool # maximum :: Ord a => URec Float a -> a # minimum :: Ord a => URec Float a -> a # | |
Traversable (URec Float :: * -> *) | |
Defined in Data.Traversable | |
Eq (URec Float p) | |
Ord (URec Float p) | |
Defined in GHC.Generics | |
Show (URec Float p) | |
Generic (URec Float p) | |
data URec Float (p :: k) | Used for marking occurrences of Since: base-4.9.0.0 |
type Rep1 (URec Float :: k -> *) | |
Defined in GHC.Generics | |
type Rep (URec Float p) | |
Defined in GHC.Generics |
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
Eq Double | |
Floating Double | Since: base-2.1 |
Data Double | Since: base-4.0.0.0 |
Defined in Data.Data gfoldl :: (forall d b. Data d => c (d -> b) -> d -> c b) -> (forall g. g -> c g) -> Double -> c Double # gunfold :: (forall b r. Data b => c (b -> r) -> c r) -> (forall r. r -> c r) -> Constr -> c Double # toConstr :: Double -> Constr # dataTypeOf :: Double -> DataType # dataCast1 :: Typeable t => (forall d. Data d => c (t d)) -> Maybe (c Double) # dataCast2 :: Typeable t => (forall d e. (Data d, Data e) => c (t d e)) -> Maybe (c Double) # gmapT :: (forall b. Data b => b -> b) -> Double -> Double # gmapQl :: (r -> r' -> r) -> r -> (forall d. Data d => d -> r') -> Double -> r # gmapQr :: (r' -> r -> r) -> r -> (forall d. Data d => d -> r') -> Double -> r # gmapQ :: (forall d. Data d => d -> u) -> Double -> [u] # gmapQi :: Int -> (forall d. Data d => d -> u) -> Double -> u # gmapM :: Monad m => (forall d. Data d => d -> m d) -> Double -> m Double # gmapMp :: MonadPlus m => (forall d. Data d => d -> m d) -> Double -> m Double # gmapMo :: MonadPlus m => (forall d. Data d => d -> m d) -> Double -> m Double # | |
Ord Double | |
Read Double | Since: base-2.1 |
RealFloat Double | Since: base-2.1 |
Defined in GHC.Float floatRadix :: Double -> Integer # floatDigits :: Double -> Int # floatRange :: Double -> (Int, Int) # decodeFloat :: Double -> (Integer, Int) # encodeFloat :: Integer -> Int -> Double # significand :: Double -> Double # scaleFloat :: Int -> Double -> Double # isInfinite :: Double -> Bool # isDenormalized :: Double -> Bool # isNegativeZero :: Double -> Bool # | |
Generic1 (URec Double :: k -> *) | |
Functor (URec Double :: * -> *) | |
Foldable (URec Double :: * -> *) | |
Defined in Data.Foldable fold :: Monoid m => URec Double m -> m # foldMap :: Monoid m => (a -> m) -> URec Double a -> m # foldr :: (a -> b -> b) -> b -> URec Double a -> b # foldr' :: (a -> b -> b) -> b -> URec Double a -> b # foldl :: (b -> a -> b) -> b -> URec Double a -> b # foldl' :: (b -> a -> b) -> b -> URec Double a -> b # foldr1 :: (a -> a -> a) -> URec Double a -> a # foldl1 :: (a -> a -> a) -> URec Double a -> a # toList :: URec Double a -> [a] # null :: URec Double a -> Bool # length :: URec Double a -> Int # elem :: Eq a => a -> URec Double a -> Bool # maximum :: Ord a => URec Double a -> a # minimum :: Ord a => URec Double a -> a # | |
Traversable (URec Double :: * -> *) | |
Defined in Data.Traversable | |
Eq (URec Double p) | |
Ord (URec Double p) | |
Defined in GHC.Generics 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 # | |
Show (URec Double p) | |
Generic (URec Double p) | |
data URec Double (p :: k) | Used for marking occurrences of Since: base-4.9.0.0 |
type Rep1 (URec Double :: k -> *) | |
Defined in GHC.Generics | |
type Rep (URec Double p) | |
Defined in GHC.Generics |
Basic numeric class.
Unary negation.
Absolute value.
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
Num Int | Since: base-2.1 |
Num Int8 | Since: base-2.1 |
Num Int16 | Since: base-2.1 |
Num Int32 | Since: base-2.1 |
Num Int64 | Since: base-2.1 |
Num Integer | Since: base-2.1 |
Num Word | Since: base-2.1 |
Num Word8 | Since: base-2.1 |
Num Word16 | Since: base-2.1 |
Num Word32 | Since: base-2.1 |
Num Word64 | Since: base-2.1 |
Integral a => Num (Ratio a) | Since: base-2.0.1 |
Num a => Num (Min a) | Since: base-4.9.0.0 |
Num a => Num (Max a) | Since: base-4.9.0.0 |
Num a => Num (Sum a) | |
Num a => Num (Product a) | |
Defined in Data.Semigroup.Internal | |
Num a => Num (Down a) | Since: base-4.11.0.0 |
Num a => Num (Const a b) | |
Num (f a) => Num (Alt f a) | |
class (Num a, Ord a) => Real a where #
toRational :: a -> Rational #
the rational equivalent of its real argument with full precision
Instances
class (Real a, Enum a) => Integral a where #
Integral numbers, supporting integer division.
quot :: a -> a -> a infixl 7 #
integer division truncated toward zero
integer remainder, satisfying
(x `quot` y)*y + (x `rem` y) == x
integer division truncated toward negative infinity
integer modulus, satisfying
(x `div` y)*y + (x `mod` y) == x
conversion to Integer
Instances
Integral Int | Since: base-2.0.1 |
Integral Int8 | Since: base-2.1 |
Integral Int16 | Since: base-2.1 |
Integral Int32 | Since: base-2.1 |
Integral Int64 | Since: base-2.1 |
Integral Integer | Since: base-2.0.1 |
Defined in GHC.Real | |
Integral Word | Since: base-2.1 |
Integral Word8 | Since: base-2.1 |
Integral Word16 | Since: base-2.1 |
Integral Word32 | Since: base-2.1 |
Integral Word64 | Since: base-2.1 |
Integral a => Integral (Const a b) | |
Defined in Data.Functor.Const |
class Num a => Fractional a where #
Fractional numbers, supporting real division.
fromRational, (recip | (/))
fractional division
reciprocal fraction
fromRational :: Rational -> a #
Conversion from a Rational
(that is
).
A floating literal stands for an application of Ratio
Integer
fromRational
to a value of type Rational
, so such literals have type
(
.Fractional
a) => a
Instances
Integral a => Fractional (Ratio a) | Since: base-2.0.1 |
Fractional a => Fractional (Const a b) | |
class Fractional a => Floating a where #
Trigonometric and hyperbolic functions and related functions.
Instances
Floating Double | Since: base-2.1 |
Floating Float | Since: base-2.1 |
Floating a => Floating (Const a b) | |
Defined in Data.Functor.Const exp :: Const a b -> Const a b # log :: Const a b -> Const a b # sqrt :: Const a b -> Const a b # (**) :: Const a b -> Const a b -> Const a b # logBase :: Const a b -> Const a b -> Const a b # sin :: Const a b -> Const a b # cos :: Const a b -> Const a b # tan :: Const a b -> Const a b # asin :: Const a b -> Const a b # acos :: Const a b -> Const a b # atan :: Const a b -> Const a b # sinh :: Const a b -> Const a b # cosh :: Const a b -> Const a b # tanh :: Const a b -> Const a b # asinh :: Const a b -> Const a b # acosh :: Const a b -> Const a b # atanh :: Const a b -> Const a b # log1p :: Const a b -> Const a b # expm1 :: Const a b -> Const a b # |
class (Real a, Fractional a) => RealFrac a where #
Extracting components of fractions.
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 asx
; andf
is a fraction with the same type and sign asx
, and with absolute value less than1
.
The default definitions of the ceiling
, floor
, truncate
and round
functions are in terms of properFraction
.
truncate :: Integral b => a -> b #
returns the integer nearest truncate
xx
between zero and x
round :: Integral b => a -> b #
returns the nearest integer to round
xx
;
the even integer if x
is equidistant between two integers
ceiling :: Integral b => a -> b #
returns the least integer not less than ceiling
xx
floor :: Integral b => a -> b #
returns the greatest integer not greater than floor
xx
class (RealFrac a, Floating a) => RealFloat a where #
Efficient, machine-independent access to the components of a floating-point number.
floatRadix, floatDigits, floatRange, decodeFloat, encodeFloat, isNaN, isInfinite, isDenormalized, isNegativeZero, isIEEE
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
yields decodeFloat
x(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) <=
, where abs
m < b^dd
is
the value of
.
In particular, floatDigits
x
. If the type
contains a negative zero, also decodeFloat
0 = (0,0)
.
The result of decodeFloat
(-0.0) = (0,0)
is unspecified if either of
decodeFloat
x
or isNaN
x
is isInfinite
xTrue
.
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
is one of the two closest representable
floating-point numbers to encodeFloat
m nm*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
corresponds to the second component of decodeFloat
.
and for finite nonzero exponent
0 = 0x
,
.
If exponent
x = snd (decodeFloat
x) + floatDigits
xx
is a finite floating-point number, it is equal in value to
, where significand
x * b ^^ exponent
xb
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
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
True
if the argument is an IEEE floating point number
a version of arctangent taking two real floating-point arguments.
For real floating x
and y
,
computes the angle
(from the positive x-axis) of the vector from the origin to the
point atan2
y x(x,y)
.
returns a value in the range [atan2
y x-pi
,
pi
]. It follows the Common Lisp semantics for the origin when
signed zeroes are supported.
, with atan2
y 1y
in a type
that is RealFloat
, should return the same value as
.
A default definition of atan
yatan2
is provided, but implementors
can provide a more accurate implementation.
Instances
gcd :: Integral a => a -> a -> a #
is the non-negative factor of both gcd
x yx
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 44
.
= gcd
0 00
.
(That is, the common divisor that is "greatest" in the divisibility
preordering.)
Note: Since for signed fixed-width integer types,
,
the result may be negative if one of the arguments is abs
minBound
< 0
(and
necessarily is if the other is minBound
0
or
) for such types.minBound
lcm :: Integral a => a -> a -> a #
is the smallest positive integer that both lcm
x yx
and y
divide.
(^^) :: (Fractional a, Integral b) => a -> b -> a infixr 8 #
raise a number to an integral power
fromIntegral :: (Integral a, Num b) => a -> b #
general coercion from integral types
realToFrac :: (Real a, Fractional b) => a -> b #
general coercion to fractional types
Semigroup
and Monoid
The class of semigroups (types with an associative binary operation).
Instances should satisfy the associativity law:
Since: base-4.9.0.0
Instances
Semigroup Ordering | Since: base-4.9.0.0 |
Semigroup () | Since: base-4.9.0.0 |
Semigroup All | Since: base-4.9.0.0 |
Semigroup Any | Since: base-4.9.0.0 |
Semigroup [a] | Since: base-4.9.0.0 |
Semigroup a => Semigroup (Maybe a) | Since: base-4.9.0.0 |
Semigroup a => Semigroup (IO a) | Since: base-4.10.0.0 |
Ord a => Semigroup (Min a) | Since: base-4.9.0.0 |
Ord a => Semigroup (Max a) | Since: base-4.9.0.0 |
Semigroup (First a) | Since: base-4.9.0.0 |
Semigroup (Last a) | Since: base-4.9.0.0 |
Monoid m => Semigroup (WrappedMonoid m) | Since: base-4.9.0.0 |
Defined in Data.Semigroup (<>) :: WrappedMonoid m -> WrappedMonoid m -> WrappedMonoid m # sconcat :: NonEmpty (WrappedMonoid m) -> WrappedMonoid m # stimes :: Integral b => b -> WrappedMonoid m -> WrappedMonoid m # | |
Semigroup a => Semigroup (Option a) | Since: base-4.9.0.0 |
Semigroup a => Semigroup (Dual a) | Since: base-4.9.0.0 |
Semigroup (Endo a) | Since: base-4.9.0.0 |
Num a => Semigroup (Sum a) | Since: base-4.9.0.0 |
Num a => Semigroup (Product a) | Since: base-4.9.0.0 |
Semigroup a => Semigroup (Down a) | Since: base-4.11.0.0 |
Semigroup (NonEmpty a) | Since: base-4.9.0.0 |
Semigroup b => Semigroup (a -> b) | Since: base-4.9.0.0 |
Semigroup (Either a b) | Since: base-4.9.0.0 |
(Semigroup a, Semigroup b) => Semigroup (a, b) | Since: base-4.9.0.0 |
(Semigroup a, Semigroup b, Semigroup c) => Semigroup (a, b, c) | Since: base-4.9.0.0 |
Semigroup a => Semigroup (Const a b) | |
Alternative f => Semigroup (Alt f a) | Since: base-4.9.0.0 |
(Semigroup a, Semigroup b, Semigroup c, Semigroup d) => Semigroup (a, b, c, d) | Since: base-4.9.0.0 |
(Semigroup a, Semigroup b, Semigroup c, Semigroup d, Semigroup e) => Semigroup (a, b, c, d, e) | Since: base-4.9.0.0 |
sconcat :: Semigroup a => NonEmpty a -> a #
Reduce a non-empty list with <>
The default definition should be sufficient, but this can be overridden for efficiency.
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 laws:
x
<>
mempty
= xmempty
<>
x = xx
(<>
(y<>
z) = (x<>
y)<>
zSemigroup
law)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 newtype
s and make those instances
of Monoid
, e.g. Sum
and Product
.
NOTE: Semigroup
is a superclass of Monoid
since base-4.11.0.0.
Identity of mappend
An associative operation
NOTE: This method is redundant and has the default
implementation
since base-4.11.0.0.mappend
= '(<>)'
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.
Instances
Monoid Ordering | Since: base-2.1 |
Monoid () | Since: base-2.1 |
Monoid All | Since: base-2.1 |
Monoid Any | Since: base-2.1 |
Monoid [a] | Since: base-2.1 |
Semigroup a => Monoid (Maybe a) | Lift a semigroup into Since 4.11.0: constraint on inner Since: base-2.1 |
Monoid a => Monoid (IO a) | Since: base-4.9.0.0 |
(Ord a, Bounded a) => Monoid (Min a) | Since: base-4.9.0.0 |
(Ord a, Bounded a) => Monoid (Max a) | Since: base-4.9.0.0 |
Monoid m => Monoid (WrappedMonoid m) | Since: base-4.9.0.0 |
Defined in Data.Semigroup mempty :: WrappedMonoid m # mappend :: WrappedMonoid m -> WrappedMonoid m -> WrappedMonoid m # mconcat :: [WrappedMonoid m] -> WrappedMonoid m # | |
Semigroup a => Monoid (Option a) | Since: base-4.9.0.0 |
Monoid a => Monoid (Dual a) | Since: base-2.1 |
Monoid (Endo a) | Since: base-2.1 |
Num a => Monoid (Sum a) | Since: base-2.1 |
Num a => Monoid (Product a) | Since: base-2.1 |
Monoid a => Monoid (Down a) | Since: base-4.11.0.0 |
Monoid b => Monoid (a -> b) | Since: base-2.1 |
(Monoid a, Monoid b) => Monoid (a, b) | Since: base-2.1 |
(Monoid a, Monoid b, Monoid c) => Monoid (a, b, c) | Since: base-2.1 |
Monoid a => Monoid (Const a b) | |
Alternative f => Monoid (Alt f a) | Since: base-4.8.0.0 |
(Monoid a, Monoid b, Monoid c, Monoid d) => Monoid (a, b, c, d) | Since: base-2.1 |
(Monoid a, Monoid b, Monoid c, Monoid d, Monoid e) => Monoid (a, b, c, d, e) | Since: base-2.1 |
Functor
, Applicative
, Monad
, and Alternative
class Functor (f :: * -> *) where #
The Functor
class is used for types that can be mapped over.
Instances of Functor
should satisfy the following laws:
fmap id == id fmap (f . g) == fmap f . fmap g
The instances of Functor
for lists, Maybe
and IO
satisfy these laws.
Instances
Functor [] | Since: base-2.1 |
Functor Maybe | Since: base-2.1 |
Functor IO | Since: base-2.1 |
Functor Par1 | |
Functor Min | Since: base-4.9.0.0 |
Functor Max | Since: base-4.9.0.0 |
Functor First | Since: base-4.9.0.0 |
Functor Last | Since: base-4.9.0.0 |
Functor Option | Since: base-4.9.0.0 |
Functor ZipList | |
Functor Dual | Since: base-4.8.0.0 |
Functor Sum | Since: base-4.8.0.0 |
Functor Product | Since: base-4.8.0.0 |
Functor Down | Since: base-4.11.0.0 |
Functor ReadPrec | Since: base-2.1 |
Functor ReadP | Since: base-2.1 |
Functor NonEmpty | Since: base-4.9.0.0 |
Functor P | |
Defined in Text.ParserCombinators.ReadP | |
Functor (Either a) | Since: base-3.0 |
Functor (V1 :: * -> *) | Since: base-4.9.0.0 |
Functor (U1 :: * -> *) | Since: base-4.9.0.0 |
Functor ((,) a) | Since: base-2.1 |
Functor (Array i) | Since: base-2.1 |
Functor (Arg a) | Since: base-4.9.0.0 |
Monad m => Functor (WrappedMonad m) | Since: base-2.1 |
Defined in Control.Applicative fmap :: (a -> b) -> WrappedMonad m a -> WrappedMonad m b # (<$) :: a -> WrappedMonad m b -> WrappedMonad m a # | |
Arrow a => Functor (ArrowMonad a) | Since: base-4.6.0.0 |
Defined in Control.Arrow fmap :: (a0 -> b) -> ArrowMonad a a0 -> ArrowMonad a b # (<$) :: a0 -> ArrowMonad a b -> ArrowMonad a a0 # | |
Functor f => Functor (Rec1 f) | |
Functor (URec Char :: * -> *) | |
Functor (URec Double :: * -> *) | |
Functor (URec Float :: * -> *) | |
Functor (URec Int :: * -> *) | |
Functor (URec Word :: * -> *) | |
Functor (URec (Ptr ()) :: * -> *) | |
Arrow a => Functor (WrappedArrow a b) | Since: base-2.1 |
Defined in Control.Applicative fmap :: (a0 -> b0) -> WrappedArrow a b a0 -> WrappedArrow a b b0 # (<$) :: a0 -> WrappedArrow a b b0 -> WrappedArrow a b a0 # | |
Functor (Const m :: * -> *) | Since: base-2.1 |
Functor f => Functor (Alt f) | |
Functor ((->) r :: * -> *) | Since: base-2.1 |
Functor (K1 i c :: * -> *) | |
(Functor f, Functor g) => Functor (f :+: g) | |
(Functor f, Functor g) => Functor (f :*: g) | |
Functor f => Functor (M1 i c f) | |
(Functor f, Functor g) => Functor (f :.: g) | |
(<$>) :: Functor f => (a -> b) -> f a -> f b infixl 4 #
An infix synonym for fmap
.
The name of this operator is an allusion to $
.
Note the similarities between their types:
($) :: (a -> b) -> a -> b (<$>) :: Functor f => (a -> b) -> f a -> f b
Whereas $
is function application, <$>
is function
application lifted over a Functor
.
Examples
Convert from a
to a Maybe
Int
using Maybe
String
show
:
>>>
show <$> Nothing
Nothing>>>
show <$> Just 3
Just "3"
Convert from an
to an Either
Int
Int
Either
Int
String
using show
:
>>>
show <$> Left 17
Left 17>>>
show <$> Right 17
Right "17"
Double each element of a list:
>>>
(*2) <$> [1,2,3]
[2,4,6]
Apply even
to the second element of a pair:
>>>
even <$> (2,2)
(2,True)
class Functor f => Applicative (f :: * -> *) where #
A functor with application, providing operations to
A minimal complete definition must include implementations of pure
and of either <*>
or liftA2
. If it defines both, then they must behave
the same as their default definitions:
(<*>
) =liftA2
id
liftA2
f x y = f<$>
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).
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.
(*>) :: f a -> f b -> f b infixl 4 #
Sequence actions, discarding the value of the first argument.
(<*) :: f a -> f b -> f a infixl 4 #
Sequence actions, discarding the value of the second argument.
Instances
Applicative [] | Since: base-2.1 |
Applicative Maybe | Since: base-2.1 |
Applicative IO | Since: base-2.1 |
Applicative Par1 | Since: base-4.9.0.0 |
Applicative Min | Since: base-4.9.0.0 |
Applicative Max | Since: base-4.9.0.0 |
Applicative First | Since: base-4.9.0.0 |
Applicative Last | Since: base-4.9.0.0 |
Applicative Option | Since: base-4.9.0.0 |
Applicative ZipList | f '<$>' 'ZipList' xs1 '<*>' ... '<*>' 'ZipList' xsN = 'ZipList' (zipWithN f xs1 ... xsN) where (\a b c -> stimes c [a, b]) <$> ZipList "abcd" <*> ZipList "567" <*> ZipList [1..] = ZipList (zipWith3 (\a b c -> stimes c [a, b]) "abcd" "567" [1..]) = ZipList {getZipList = ["a5","b6b6","c7c7c7"]} Since: base-2.1 |
Applicative Dual | Since: base-4.8.0.0 |
Applicative Sum | Since: base-4.8.0.0 |
Applicative Product | Since: base-4.8.0.0 |
Applicative Down | Since: base-4.11.0.0 |
Applicative ReadPrec | Since: base-4.6.0.0 |
Applicative ReadP | Since: base-4.6.0.0 |
Applicative NonEmpty | Since: base-4.9.0.0 |
Applicative P | Since: base-4.5.0.0 |
Applicative (Either e) | Since: base-3.0 |
Applicative (U1 :: * -> *) | Since: base-4.9.0.0 |
Monoid a => Applicative ((,) a) | For tuples, the ("hello ", (+15)) <*> ("world!", 2002) ("hello world!",2017) Since: base-2.1 |
Monad m => Applicative (WrappedMonad m) | Since: base-2.1 |
Defined in Control.Applicative pure :: a -> WrappedMonad m a # (<*>) :: WrappedMonad m (a -> b) -> WrappedMonad m a -> WrappedMonad m b # liftA2 :: (a -> b -> c) -> WrappedMonad m a -> WrappedMonad m b -> WrappedMonad m c # (*>) :: WrappedMonad m a -> WrappedMonad m b -> WrappedMonad m b # (<*) :: WrappedMonad m a -> WrappedMonad m b -> WrappedMonad m a # | |
Arrow a => Applicative (ArrowMonad a) | Since: base-4.6.0.0 |
Defined in Control.Arrow pure :: a0 -> ArrowMonad a a0 # (<*>) :: ArrowMonad a (a0 -> b) -> ArrowMonad a a0 -> ArrowMonad a b # liftA2 :: (a0 -> b -> c) -> ArrowMonad a a0 -> ArrowMonad a b -> ArrowMonad a c # (*>) :: ArrowMonad a a0 -> ArrowMonad a b -> ArrowMonad a b # (<*) :: ArrowMonad a a0 -> ArrowMonad a b -> ArrowMonad a a0 # | |
Applicative f => Applicative (Rec1 f) | Since: base-4.9.0.0 |
Arrow a => Applicative (WrappedArrow a b) | Since: base-2.1 |
Defined in Control.Applicative pure :: a0 -> WrappedArrow a b a0 # (<*>) :: WrappedArrow a b (a0 -> b0) -> WrappedArrow a b a0 -> WrappedArrow a b b0 # liftA2 :: (a0 -> b0 -> c) -> WrappedArrow a b a0 -> WrappedArrow a b b0 -> WrappedArrow a b c # (*>) :: WrappedArrow a b a0 -> WrappedArrow a b b0 -> WrappedArrow a b b0 # (<*) :: WrappedArrow a b a0 -> WrappedArrow a b b0 -> WrappedArrow a b a0 # | |
Monoid m => Applicative (Const m :: * -> *) | Since: base-2.0.1 |
Applicative f => Applicative (Alt f) | |
Applicative ((->) a :: * -> *) | Since: base-2.1 |
(Applicative f, Applicative g) => Applicative (f :*: g) | Since: base-4.9.0.0 |
Applicative f => Applicative (M1 i c f) | Since: base-4.9.0.0 |
(Applicative f, Applicative g) => Applicative (f :.: g) | Since: base-4.9.0.0 |
class Applicative m => Monad (m :: * -> *) 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 laws:
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.
(>>=) :: 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.
(>>) :: 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.
Inject a value into the monadic type.
Instances
Monad [] | Since: base-2.1 |
Monad Maybe | Since: base-2.1 |
Monad IO | Since: base-2.1 |
Monad Par1 | Since: base-4.9.0.0 |
Monad Min | Since: base-4.9.0.0 |
Monad Max | Since: base-4.9.0.0 |
Monad First | Since: base-4.9.0.0 |
Monad Last | Since: base-4.9.0.0 |
Monad Option | Since: base-4.9.0.0 |
Monad Dual | Since: base-4.8.0.0 |
Monad Sum | Since: base-4.8.0.0 |
Monad Product | Since: base-4.8.0.0 |
Monad Down | Since: base-4.11.0.0 |
Monad ReadPrec | Since: base-2.1 |
Monad ReadP | Since: base-2.1 |
Monad NonEmpty | Since: base-4.9.0.0 |
Monad P | Since: base-2.1 |
Monad (Either e) | Since: base-4.4.0.0 |
Monad (U1 :: * -> *) | Since: base-4.9.0.0 |
Monoid a => Monad ((,) a) | Since: base-4.9.0.0 |
Monad m => Monad (WrappedMonad m) | |
Defined in Control.Applicative (>>=) :: WrappedMonad m a -> (a -> WrappedMonad m b) -> WrappedMonad m b # (>>) :: WrappedMonad m a -> WrappedMonad m b -> WrappedMonad m b # return :: a -> WrappedMonad m a # fail :: String -> WrappedMonad m a # | |
ArrowApply a => Monad (ArrowMonad a) | Since: base-2.1 |
Defined in Control.Arrow (>>=) :: ArrowMonad a a0 -> (a0 -> ArrowMonad a b) -> ArrowMonad a b # (>>) :: ArrowMonad a a0 -> ArrowMonad a b -> ArrowMonad a b # return :: a0 -> ArrowMonad a a0 # fail :: String -> ArrowMonad a a0 # | |
Monad f => Monad (Rec1 f) | Since: base-4.9.0.0 |
Monad f => Monad (Alt f) | |
Monad ((->) r :: * -> *) | Since: base-2.1 |
(Monad f, Monad g) => Monad (f :*: g) | Since: base-4.9.0.0 |
Monad f => Monad (M1 i c f) | Since: base-4.9.0.0 |
class Applicative f => Alternative (f :: * -> *) where #
A monoid on applicative functors.
If defined, some
and many
should be the least solutions
of the equations:
The identity of <|>
(<|>) :: f a -> f a -> f a infixl 3 #
An associative binary operation
One or more.
Zero or more.
Instances
class Monad m => MonadFail (m :: * -> *) #
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
Instances
MonadFail [] | Since: base-4.9.0.0 |
Defined in Control.Monad.Fail | |
MonadFail Maybe | Since: base-4.9.0.0 |
Defined in Control.Monad.Fail | |
MonadFail IO | Since: base-4.9.0.0 |
Defined in Control.Monad.Fail | |
MonadFail ReadPrec | Since: base-4.9.0.0 |
Defined in Text.ParserCombinators.ReadPrec | |
MonadFail ReadP | Since: base-4.9.0.0 |
Defined in Text.ParserCombinators.ReadP | |
MonadFail P | Since: base-4.9.0.0 |
Defined in Text.ParserCombinators.ReadP |
class (Alternative m, Monad m) => MonadPlus (m :: * -> *) where #
Monads that also support choice and failure.
The identity of mplus
. It should also satisfy the equations
mzero >>= f = mzero v >> mzero = mzero
The default definition is
mzero = empty
An associative operation. The default definition is
mplus = (<|>
)
Instances
MonadPlus [] | Since: base-2.1 |
MonadPlus Maybe | Since: base-2.1 |
MonadPlus IO | Since: base-4.9.0.0 |
MonadPlus Option | Since: base-4.9.0.0 |
MonadPlus ReadPrec | Since: base-2.1 |
MonadPlus ReadP | Since: base-2.1 |
MonadPlus P | Since: base-2.1 |
Defined in Text.ParserCombinators.ReadP | |
MonadPlus (U1 :: * -> *) | Since: base-4.9.0.0 |
(ArrowApply a, ArrowPlus a) => MonadPlus (ArrowMonad a) | Since: base-4.6.0.0 |
Defined in Control.Arrow mzero :: ArrowMonad a a0 # mplus :: ArrowMonad a a0 -> ArrowMonad a a0 -> ArrowMonad a a0 # | |
MonadPlus f => MonadPlus (Rec1 f) | Since: base-4.9.0.0 |
MonadPlus f => MonadPlus (Alt f) | |
(MonadPlus f, MonadPlus g) => MonadPlus (f :*: g) | Since: base-4.9.0.0 |
MonadPlus f => MonadPlus (M1 i c f) | Since: base-4.9.0.0 |
guard :: Alternative f => Bool -> f () #
Conditional failure of Alternative
computations. Defined by
guard True =pure
() guard False =empty
Examples
Common uses of guard
include conditionally signaling an error in
an error monad and conditionally rejecting the current choice in an
Alternative
-based parser.
As an example of signaling an error in the error monad Maybe
,
consider a safe division function safeDiv x y
that returns
Nothing
when the denominator y
is zero and
otherwise. For example:Just
(x `div`
y)
>>> safeDiv 4 0 Nothing >>> safeDiv 4 2 Just 2
A definition of safeDiv
using guards, but not guard
:
safeDiv :: Int -> Int -> Maybe Int safeDiv x y | y /= 0 = Just (x `div` y) | otherwise = Nothing
A definition of safeDiv
using guard
and Monad
do
-notation:
safeDiv :: Int -> Int -> Maybe Int safeDiv x y = do guard (y /= 0) return (x `div` y)
($>) :: Functor f => f a -> b -> f b infixl 4 #
Flipped version of <$
.
Examples
Replace the contents of a
with a constant Maybe
Int
String
:
>>>
Nothing $> "foo"
Nothing>>>
Just 90210 $> "foo"
Just "foo"
Replace the contents of an
with a constant
Either
Int
Int
String
, resulting in an
:Either
Int
String
>>>
Left 8675309 $> "foo"
Left 8675309>>>
Right 8675309 $> "foo"
Right "foo"
Replace each element of a list with a constant String
:
>>>
[1,2,3] $> "foo"
["foo","foo","foo"]
Replace the second element of a pair with a constant String
:
>>>
(1,2) $> "foo"
(1,"foo")
Since: base-4.7.0.0
forM :: (Traversable t, Monad m) => t a -> (a -> m b) -> m (t b) #
sequence_ :: (Foldable t, Monad m) => t (m a) -> m () #
Evaluate each monadic action in the structure from left to right,
and ignore the results. For a version that doesn't ignore the
results see sequence
.
As of base 4.8.0.0, sequence_
is just sequenceA_
, specialized
to Monad
.
(=<<) :: Monad m => (a -> m b) -> m a -> m b infixr 1 #
Same as >>=
, but with the arguments interchanged.
when :: Applicative f => Bool -> f () -> f () #
Conditional execution of Applicative
expressions. For example,
when debug (putStrLn "Debugging")
will output the string Debugging
if the Boolean value debug
is True
, and otherwise do nothing.
unless :: Applicative f => Bool -> f () -> f () #
The reverse of when
.
void :: Functor f => f a -> f () #
discards or ignores the result of evaluation, such
as the return value of an void
valueIO
action.
Examples
Replace the contents of a
with unit:Maybe
Int
>>>
void Nothing
Nothing>>>
void (Just 3)
Just ()
Replace the contents of an
with unit,
resulting in an Either
Int
Int
:Either
Int
'()'
>>>
void (Left 8675309)
Left 8675309>>>
void (Right 8675309)
Right ()
Replace every element of a list with unit:
>>>
void [1,2,3]
[(),(),()]
Replace the second element of a pair with unit:
>>>
void (1,2)
(1,())
Discard the result of an IO
action:
>>>
mapM print [1,2]
1 2 [(),()]>>>
void $ mapM print [1,2]
1 2
replicateM :: Applicative m => Int -> m a -> m [a] #
performs the action replicateM
n actn
times,
gathering the results.
replicateM_ :: Applicative m => Int -> m a -> m () #
Like replicateM
, but discards the result.
forever :: Applicative f => f a -> f b #
repeats the action infinitely.forever
act
(>=>) :: Monad m => (a -> m b) -> (b -> m c) -> a -> m c infixr 1 #
Left-to-right Kleisli composition of monads.
foldM :: (Foldable t, Monad m) => (b -> a -> m b) -> b -> t a -> m b #
The foldM
function is analogous to foldl
, except that its result is
encapsulated in a monad. Note that foldM
works from left-to-right over
the list arguments. This could be an issue where (
and the `folded
function' are not commutative.>>
)
foldM f a1 [x1, x2, ..., xm] == do a2 <- f a1 x1 a3 <- f a2 x2 ... f am xm
If right-to-left evaluation is required, the input list should be reversed.
foldM_ :: (Foldable t, Monad m) => (b -> a -> m b) -> b -> t a -> m () #
Like foldM
, but discards the result.
join :: Monad m => m (m a) -> m a #
The join
function is the conventional monad join operator. It
is used to remove one level of monadic structure, projecting its
bound argument into the outer level.
liftM2 :: Monad m => (a1 -> a2 -> r) -> m a1 -> m a2 -> m r #
Promote a function to a monad, scanning the monadic arguments from left to right. For example,
liftM2 (+) [0,1] [0,2] = [0,2,1,3] liftM2 (+) (Just 1) Nothing = Nothing
liftM3 :: Monad m => (a1 -> a2 -> a3 -> r) -> m a1 -> m a2 -> m a3 -> m r #
Promote a function to a monad, scanning the monadic arguments from
left to right (cf. liftM2
).
liftM4 :: Monad m => (a1 -> a2 -> a3 -> a4 -> r) -> m a1 -> m a2 -> m a3 -> m a4 -> m r #
Promote a function to a monad, scanning the monadic arguments from
left to right (cf. liftM2
).
liftM5 :: Monad m => (a1 -> a2 -> a3 -> a4 -> a5 -> r) -> m a1 -> m a2 -> m a3 -> m a4 -> m a5 -> m r #
Promote a function to a monad, scanning the monadic arguments from
left to right (cf. liftM2
).
liftA :: Applicative f => (a -> b) -> f a -> f b #
liftA2 :: Applicative f => (a -> b -> c) -> f a -> f b -> f c #
liftA3 :: Applicative f => (a -> b -> c -> d) -> f a -> f b -> f c -> f d #
Lift a ternary function to actions.
liftA4 :: Applicative f => (a -> b -> c -> d -> e) -> f a -> f b -> f c -> f d -> f e Source #
Lift a 4-ary function to actions.
liftA5 :: Applicative f => (a -> b -> c -> d -> e -> g) -> f a -> f b -> f c -> f d -> f e -> f g Source #
Lift a 5-ary function to actions.
Foldable
and Traversable
class Foldable (t :: * -> *) where #
Data structures that can be folded.
For example, given a data type
data Tree a = Empty | Leaf a | Node (Tree a) a (Tree a)
a suitable instance would be
instance Foldable Tree where foldMap f Empty = mempty foldMap f (Leaf x) = f x foldMap f (Node l k r) = foldMap f l `mappend` f k `mappend` foldMap f r
This is suitable even for abstract types, as the monoid is assumed
to satisfy the monoid laws. Alternatively, one could define foldr
:
instance Foldable Tree where foldr f z Empty = z foldr f z (Leaf x) = f x z foldr f z (Node l k r) = foldr f (f k (foldr f z r)) l
Foldable
instances are expected to satisfy the following laws:
foldr f z t = appEndo (foldMap (Endo . f) t ) z
foldl f z t = appEndo (getDual (foldMap (Dual . Endo . flip f) t)) z
fold = foldMap id
length = getSum . foldMap (Sum . const 1)
sum
, product
, maximum
, and minimum
should all be essentially
equivalent to foldMap
forms, such as
sum = getSum . foldMap Sum
but may be less defined.
If the type is also a Functor
instance, it should satisfy
foldMap f = fold . fmap f
which implies that
foldMap f . fmap g = foldMap (f . g)
fold :: Monoid m => t m -> m #
Combine the elements of a structure using a monoid.
foldMap :: Monoid m => (a -> m) -> t a -> m #
Map each element of the structure to a monoid, and combine the results.
foldr :: (a -> b -> b) -> b -> t a -> b #
Right-associative fold of a structure.
In the case of lists, foldr
, when applied to a binary operator, a
starting value (typically the right-identity of the operator), and a
list, reduces the list using the binary operator, from right to left:
foldr f z [x1, x2, ..., xn] == x1 `f` (x2 `f` ... (xn `f` z)...)
Note that, since the head of the resulting expression is produced by
an application of the operator to the first element of the list,
foldr
can produce a terminating expression from an infinite list.
For a general Foldable
structure this should be semantically identical
to,
foldr f z =foldr
f z .toList
foldl :: (b -> a -> b) -> b -> t a -> b #
Left-associative fold of a structure.
In the case of lists, foldl
, when applied to a binary
operator, a starting value (typically the left-identity of the operator),
and a list, reduces the list using the binary operator, from left to
right:
foldl f z [x1, x2, ..., xn] == (...((z `f` x1) `f` x2) `f`...) `f` xn
Note that to produce the outermost application of the operator the
entire input list must be traversed. This means that foldl'
will
diverge if given an infinite list.
Also note that if you want an efficient left-fold, you probably want to
use foldl'
instead of foldl
. The reason for this is that latter does
not force the "inner" results (e.g. z
in the above example)
before applying them to the operator (e.g. to f
x1(
). This results
in a thunk chain f
x2)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
Instances
Foldable [] | Since: base-2.1 |
Defined in Data.Foldable fold :: Monoid m => [m] -> m # foldMap :: Monoid m => (a -> m) -> [a] -> m # foldr :: (a -> b -> b) -> b -> [a] -> b # foldr' :: (a -> b -> b) -> b -> [a] -> b # foldl :: (b -> a -> b) -> b -> [a] -> b # foldl' :: (b -> a -> b) -> b -> [a] -> b # foldr1 :: (a -> a -> a) -> [a] -> a # foldl1 :: (a -> a -> a) -> [a] -> a # elem :: Eq a => a -> [a] -> Bool # maximum :: Ord a => [a] -> a # | |
Foldable Maybe | Since: base-2.1 |
Defined in Data.Foldable fold :: Monoid m => Maybe m -> m # foldMap :: Monoid m => (a -> m) -> Maybe a -> m # foldr :: (a -> b -> b) -> b -> Maybe a -> b # foldr' :: (a -> b -> b) -> b -> Maybe a -> b # foldl :: (b -> a -> b) -> b -> Maybe a -> b # foldl' :: (b -> a -> b) -> b -> Maybe a -> b # foldr1 :: (a -> a -> a) -> Maybe a -> a # foldl1 :: (a -> a -> a) -> Maybe a -> a # elem :: Eq a => a -> Maybe a -> Bool # maximum :: Ord a => Maybe a -> a # minimum :: Ord a => Maybe a -> a # | |
Foldable Par1 | |
Defined in Data.Foldable fold :: Monoid m => Par1 m -> m # foldMap :: Monoid m => (a -> m) -> Par1 a -> m # foldr :: (a -> b -> b) -> b -> Par1 a -> b # foldr' :: (a -> b -> b) -> b -> Par1 a -> b # foldl :: (b -> a -> b) -> b -> Par1 a -> b # foldl' :: (b -> a -> b) -> b -> Par1 a -> b # foldr1 :: (a -> a -> a) -> Par1 a -> a # foldl1 :: (a -> a -> a) -> Par1 a -> a # elem :: Eq a => a -> Par1 a -> Bool # maximum :: Ord a => Par1 a -> a # | |
Foldable Min | Since: base-4.9.0.0 |
Defined in Data.Semigroup fold :: Monoid m => Min m -> m # foldMap :: Monoid m => (a -> m) -> Min a -> m # foldr :: (a -> b -> b) -> b -> Min a -> b # foldr' :: (a -> b -> b) -> b -> Min a -> b # foldl :: (b -> a -> b) -> b -> Min a -> b # foldl' :: (b -> a -> b) -> b -> Min a -> b # foldr1 :: (a -> a -> a) -> Min a -> a # foldl1 :: (a -> a -> a) -> Min a -> a # elem :: Eq a => a -> Min a -> Bool # maximum :: Ord a => Min a -> a # | |
Foldable Max | Since: base-4.9.0.0 |
Defined in Data.Semigroup fold :: Monoid m => Max m -> m # foldMap :: Monoid m => (a -> m) -> Max a -> m # foldr :: (a -> b -> b) -> b -> Max a -> b # foldr' :: (a -> b -> b) -> b -> Max a -> b # foldl :: (b -> a -> b) -> b -> Max a -> b # foldl' :: (b -> a -> b) -> b -> Max a -> b # foldr1 :: (a -> a -> a) -> Max a -> a # foldl1 :: (a -> a -> a) -> Max a -> a # elem :: Eq a => a -> Max a -> Bool # maximum :: Ord a => Max a -> a # | |
Foldable First | Since: base-4.9.0.0 |
Defined in Data.Semigroup fold :: Monoid m => First m -> m # foldMap :: Monoid m => (a -> m) -> First a -> m # foldr :: (a -> b -> b) -> b -> First a -> b # foldr' :: (a -> b -> b) -> b -> First a -> b # foldl :: (b -> a -> b) -> b -> First a -> b # foldl' :: (b -> a -> b) -> b -> First a -> b # foldr1 :: (a -> a -> a) -> First a -> a # foldl1 :: (a -> a -> a) -> First a -> a # elem :: Eq a => a -> First a -> Bool # maximum :: Ord a => First a -> a # minimum :: Ord a => First a -> a # | |
Foldable Last | Since: base-4.9.0.0 |
Defined in Data.Semigroup fold :: Monoid m => Last m -> m # foldMap :: Monoid m => (a -> m) -> Last a -> m # foldr :: (a -> b -> b) -> b -> Last a -> b # foldr' :: (a -> b -> b) -> b -> Last a -> b # foldl :: (b -> a -> b) -> b -> Last a -> b # foldl' :: (b -> a -> b) -> b -> Last a -> b # foldr1 :: (a -> a -> a) -> Last a -> a # foldl1 :: (a -> a -> a) -> Last a -> a # elem :: Eq a => a -> Last a -> Bool # maximum :: Ord a => Last a -> a # | |
Foldable Option | Since: base-4.9.0.0 |
Defined in Data.Semigroup fold :: Monoid m => Option m -> m # foldMap :: Monoid m => (a -> m) -> Option a -> m # foldr :: (a -> b -> b) -> b -> Option a -> b # foldr' :: (a -> b -> b) -> b -> Option a -> b # foldl :: (b -> a -> b) -> b -> Option a -> b # foldl' :: (b -> a -> b) -> b -> Option a -> b # foldr1 :: (a -> a -> a) -> Option a -> a # foldl1 :: (a -> a -> a) -> Option a -> a # elem :: Eq a => a -> Option a -> Bool # maximum :: Ord a => Option a -> a # minimum :: Ord a => Option a -> a # | |
Foldable ZipList | |
Defined in Control.Applicative fold :: Monoid m => ZipList m -> m # foldMap :: Monoid m => (a -> m) -> ZipList a -> m # foldr :: (a -> b -> b) -> b -> ZipList a -> b # foldr' :: (a -> b -> b) -> b -> ZipList a -> b # foldl :: (b -> a -> b) -> b -> ZipList a -> b # foldl' :: (b -> a -> b) -> b -> ZipList a -> b # foldr1 :: (a -> a -> a) -> ZipList a -> a # foldl1 :: (a -> a -> a) -> ZipList a -> a # elem :: Eq a => a -> ZipList a -> Bool # maximum :: Ord a => ZipList a -> a # minimum :: Ord a => ZipList a -> a # | |
Foldable First | Since: base-4.8.0.0 |
Defined in Data.Foldable fold :: Monoid m => First m -> m # foldMap :: Monoid m => (a -> m) -> First a -> m # foldr :: (a -> b -> b) -> b -> First a -> b # foldr' :: (a -> b -> b) -> b -> First a -> b # foldl :: (b -> a -> b) -> b -> First a -> b # foldl' :: (b -> a -> b) -> b -> First a -> b # foldr1 :: (a -> a -> a) -> First a -> a # foldl1 :: (a -> a -> a) -> First a -> a # elem :: Eq a => a -> First a -> Bool # maximum :: Ord a => First a -> a # minimum :: Ord a => First a -> a # | |
Foldable Last | Since: base-4.8.0.0 |
Defined in Data.Foldable fold :: Monoid m => Last m -> m # foldMap :: Monoid m => (a -> m) -> Last a -> m # foldr :: (a -> b -> b) -> b -> Last a -> b # foldr' :: (a -> b -> b) -> b -> Last a -> b # foldl :: (b -> a -> b) -> b -> Last a -> b # foldl' :: (b -> a -> b) -> b -> Last a -> b # foldr1 :: (a -> a -> a) -> Last a -> a # foldl1 :: (a -> a -> a) -> Last a -> a # elem :: Eq a => a -> Last a -> Bool # maximum :: Ord a => Last a -> a # | |
Foldable Dual | Since: base-4.8.0.0 |
Defined in Data.Foldable fold :: Monoid m => Dual m -> m # foldMap :: Monoid m => (a -> m) -> Dual a -> m # foldr :: (a -> b -> b) -> b -> Dual a -> b # foldr' :: (a -> b -> b) -> b -> Dual a -> b # foldl :: (b -> a -> b) -> b -> Dual a -> b # foldl' :: (b -> a -> b) -> b -> Dual a -> b # foldr1 :: (a -> a -> a) -> Dual a -> a # foldl1 :: (a -> a -> a) -> Dual a -> a # elem :: Eq a => a -> Dual a -> Bool # maximum :: Ord a => Dual a -> a # | |
Foldable Sum | Since: base-4.8.0.0 |
Defined in Data.Foldable fold :: Monoid m => Sum m -> m # foldMap :: Monoid m => (a -> m) -> Sum a -> m # foldr :: (a -> b -> b) -> b -> Sum a -> b # foldr' :: (a -> b -> b) -> b -> Sum a -> b # foldl :: (b -> a -> b) -> b -> Sum a -> b # foldl' :: (b -> a -> b) -> b -> Sum a -> b # foldr1 :: (a -> a -> a) -> Sum a -> a # foldl1 :: (a -> a -> a) -> Sum a -> a # elem :: Eq a => a -> Sum a -> Bool # maximum :: Ord a => Sum a -> a # | |
Foldable Product | Since: base-4.8.0.0 |
Defined in Data.Foldable fold :: Monoid m => Product m -> m # foldMap :: Monoid m => (a -> m) -> Product a -> m # foldr :: (a -> b -> b) -> b -> Product a -> b # foldr' :: (a -> b -> b) -> b -> Product a -> b # foldl :: (b -> a -> b) -> b -> Product a -> b # foldl' :: (b -> a -> b) -> b -> Product a -> b # foldr1 :: (a -> a -> a) -> Product a -> a # foldl1 :: (a -> a -> a) -> Product a -> a # elem :: Eq a => a -> Product a -> Bool # maximum :: Ord a => Product a -> a # minimum :: Ord a => Product a -> a # | |
Foldable NonEmpty | Since: base-4.9.0.0 |
Defined in Data.Foldable fold :: Monoid m => NonEmpty m -> m # foldMap :: Monoid m => (a -> m) -> NonEmpty a -> m # foldr :: (a -> b -> b) -> b -> NonEmpty a -> b # foldr' :: (a -> b -> b) -> b -> NonEmpty a -> b # foldl :: (b -> a -> b) -> b -> NonEmpty a -> b # foldl' :: (b -> a -> b) -> b -> NonEmpty a -> b # foldr1 :: (a -> a -> a) -> NonEmpty a -> a # foldl1 :: (a -> a -> a) -> NonEmpty a -> a # elem :: Eq a => a -> NonEmpty a -> Bool # maximum :: Ord a => NonEmpty a -> a # minimum :: Ord a => NonEmpty a -> a # | |
Foldable (Either a) | Since: base-4.7.0.0 |
Defined in Data.Foldable fold :: Monoid m => Either a m -> m # foldMap :: Monoid m => (a0 -> m) -> Either a a0 -> m # foldr :: (a0 -> b -> b) -> b -> Either a a0 -> b # foldr' :: (a0 -> b -> b) -> b -> Either a a0 -> b # foldl :: (b -> a0 -> b) -> b -> Either a a0 -> b # foldl' :: (b -> a0 -> b) -> b -> Either a a0 -> b # foldr1 :: (a0 -> a0 -> a0) -> Either a a0 -> a0 # foldl1 :: (a0 -> a0 -> a0) -> Either a a0 -> a0 # toList :: Either a a0 -> [a0] # length :: Either a a0 -> Int # elem :: Eq a0 => a0 -> Either a a0 -> Bool # maximum :: Ord a0 => Either a a0 -> a0 # minimum :: Ord a0 => Either a a0 -> a0 # | |
Foldable (V1 :: * -> *) | |
Defined in Data.Foldable fold :: Monoid m => V1 m -> m # foldMap :: Monoid m => (a -> m) -> V1 a -> m # foldr :: (a -> b -> b) -> b -> V1 a -> b # foldr' :: (a -> b -> b) -> b -> V1 a -> b # foldl :: (b -> a -> b) -> b -> V1 a -> b # foldl' :: (b -> a -> b) -> b -> V1 a -> b # foldr1 :: (a -> a -> a) -> V1 a -> a # foldl1 :: (a -> a -> a) -> V1 a -> a # elem :: Eq a => a -> V1 a -> Bool # maximum :: Ord a => V1 a -> a # | |
Foldable (U1 :: * -> *) | Since: base-4.9.0.0 |
Defined in Data.Foldable fold :: Monoid m => U1 m -> m # foldMap :: Monoid m => (a -> m) -> U1 a -> m # foldr :: (a -> b -> b) -> b -> U1 a -> b # foldr' :: (a -> b -> b) -> b -> U1 a -> b # foldl :: (b -> a -> b) -> b -> U1 a -> b # foldl' :: (b -> a -> b) -> b -> U1 a -> b # foldr1 :: (a -> a -> a) -> U1 a -> a # foldl1 :: (a -> a -> a) -> U1 a -> a # elem :: Eq a => a -> U1 a -> Bool # maximum :: Ord a => U1 a -> a # | |
Foldable ((,) a) | Since: base-4.7.0.0 |
Defined in Data.Foldable fold :: Monoid m => (a, m) -> m # foldMap :: Monoid m => (a0 -> m) -> (a, a0) -> m # foldr :: (a0 -> b -> b) -> b -> (a, a0) -> b # foldr' :: (a0 -> b -> b) -> b -> (a, a0) -> b # foldl :: (b -> a0 -> b) -> b -> (a, a0) -> b # foldl' :: (b -> a0 -> b) -> b -> (a, a0) -> b # foldr1 :: (a0 -> a0 -> a0) -> (a, a0) -> a0 # foldl1 :: (a0 -> a0 -> a0) -> (a, a0) -> a0 # elem :: Eq a0 => a0 -> (a, a0) -> Bool # maximum :: Ord a0 => (a, a0) -> a0 # minimum :: Ord a0 => (a, a0) -> a0 # | |
Foldable (Array i) | Since: base-4.8.0.0 |
Defined in Data.Foldable fold :: Monoid m => Array i m -> m # foldMap :: Monoid m => (a -> m) -> Array i a -> m # foldr :: (a -> b -> b) -> b -> Array i a -> b # foldr' :: (a -> b -> b) -> b -> Array i a -> b # foldl :: (b -> a -> b) -> b -> Array i a -> b # foldl' :: (b -> a -> b) -> b -> Array i a -> b # foldr1 :: (a -> a -> a) -> Array i a -> a # foldl1 :: (a -> a -> a) -> Array i a -> a # elem :: Eq a => a -> Array i a -> Bool # maximum :: Ord a => Array i a -> a # minimum :: Ord a => Array i a -> a # | |
Foldable (Arg a) | Since: base-4.9.0.0 |
Defined in Data.Semigroup fold :: Monoid m => Arg a m -> m # foldMap :: Monoid m => (a0 -> m) -> Arg a a0 -> m # foldr :: (a0 -> b -> b) -> b -> Arg a a0 -> b # foldr' :: (a0 -> b -> b) -> b -> Arg a a0 -> b # foldl :: (b -> a0 -> b) -> b -> Arg a a0 -> b # foldl' :: (b -> a0 -> b) -> b -> Arg a a0 -> b # foldr1 :: (a0 -> a0 -> a0) -> Arg a a0 -> a0 # foldl1 :: (a0 -> a0 -> a0) -> Arg a a0 -> a0 # elem :: Eq a0 => a0 -> Arg a a0 -> Bool # maximum :: Ord a0 => Arg a a0 -> a0 # minimum :: Ord a0 => Arg a a0 -> a0 # | |
Foldable (Proxy :: * -> *) | Since: base-4.7.0.0 |
Defined in Data.Foldable fold :: Monoid m => Proxy m -> m # foldMap :: Monoid m => (a -> m) -> Proxy a -> m # foldr :: (a -> b -> b) -> b -> Proxy a -> b # foldr' :: (a -> b -> b) -> b -> Proxy a -> b # foldl :: (b -> a -> b) -> b -> Proxy a -> b # foldl' :: (b -> a -> b) -> b -> Proxy a -> b # foldr1 :: (a -> a -> a) -> Proxy a -> a # foldl1 :: (a -> a -> a) -> Proxy a -> a # elem :: Eq a => a -> Proxy a -> Bool # maximum :: Ord a => Proxy a -> a # minimum :: Ord a => Proxy a -> a # | |
Foldable f => Foldable (Rec1 f) | |
Defined in Data.Foldable fold :: Monoid m => Rec1 f m -> m # foldMap :: Monoid m => (a -> m) -> Rec1 f a -> m # foldr :: (a -> b -> b) -> b -> Rec1 f a -> b # foldr' :: (a -> b -> b) -> b -> Rec1 f a -> b # foldl :: (b -> a -> b) -> b -> Rec1 f a -> b # foldl' :: (b -> a -> b) -> b -> Rec1 f a -> b # foldr1 :: (a -> a -> a) -> Rec1 f a -> a # foldl1 :: (a -> a -> a) -> Rec1 f a -> a # elem :: Eq a => a -> Rec1 f a -> Bool # maximum :: Ord a => Rec1 f a -> a # minimum :: Ord a => Rec1 f a -> a # | |
Foldable (URec Char :: * -> *) | |
Defined in Data.Foldable fold :: Monoid m => URec Char m -> m # foldMap :: Monoid m => (a -> m) -> URec Char a -> m # foldr :: (a -> b -> b) -> b -> URec Char a -> b # foldr' :: (a -> b -> b) -> b -> URec Char a -> b # foldl :: (b -> a -> b) -> b -> URec Char a -> b # foldl' :: (b -> a -> b) -> b -> URec Char a -> b # foldr1 :: (a -> a -> a) -> URec Char a -> a # foldl1 :: (a -> a -> a) -> URec Char a -> a # toList :: URec Char a -> [a] # length :: URec Char a -> Int # elem :: Eq a => a -> URec Char a -> Bool # maximum :: Ord a => URec Char a -> a # minimum :: Ord a => URec Char a -> a # | |
Foldable (URec Double :: * -> *) | |
Defined in Data.Foldable fold :: Monoid m => URec Double m -> m # foldMap :: Monoid m => (a -> m) -> URec Double a -> m # foldr :: (a -> b -> b) -> b -> URec Double a -> b # foldr' :: (a -> b -> b) -> b -> URec Double a -> b # foldl :: (b -> a -> b) -> b -> URec Double a -> b # foldl' :: (b -> a -> b) -> b -> URec Double a -> b # foldr1 :: (a -> a -> a) -> URec Double a -> a # foldl1 :: (a -> a -> a) -> URec Double a -> a # toList :: URec Double a -> [a] # null :: URec Double a -> Bool # length :: URec Double a -> Int # elem :: Eq a => a -> URec Double a -> Bool # maximum :: Ord a => URec Double a -> a # minimum :: Ord a => URec Double a -> a # | |
Foldable (URec Float :: * -> *) | |
Defined in Data.Foldable fold :: Monoid m => URec Float m -> m # foldMap :: Monoid m => (a -> m) -> URec Float a -> m # foldr :: (a -> b -> b) -> b -> URec Float a -> b # foldr' :: (a -> b -> b) -> b -> URec Float a -> b # foldl :: (b -> a -> b) -> b -> URec Float a -> b # foldl' :: (b -> a -> b) -> b -> URec Float a -> b # foldr1 :: (a -> a -> a) -> URec Float a -> a # foldl1 :: (a -> a -> a) -> URec Float a -> a # toList :: URec Float a -> [a] # null :: URec Float a -> Bool # length :: URec Float a -> Int # elem :: Eq a => a -> URec Float a -> Bool # maximum :: Ord a => URec Float a -> a # minimum :: Ord a => URec Float a -> a # | |
Foldable (URec Int :: * -> *) | |
Defined in Data.Foldable fold :: Monoid m => URec Int m -> m # foldMap :: Monoid m => (a -> m) -> URec Int a -> m # foldr :: (a -> b -> b) -> b -> URec Int a -> b # foldr' :: (a -> b -> b) -> b -> URec Int a -> b # foldl :: (b -> a -> b) -> b -> URec Int a -> b # foldl' :: (b -> a -> b) -> b -> URec Int a -> b # foldr1 :: (a -> a -> a) -> URec Int a -> a # foldl1 :: (a -> a -> a) -> URec Int a -> a # elem :: Eq a => a -> URec Int a -> Bool # maximum :: Ord a => URec Int a -> a # minimum :: Ord a => URec Int a -> a # | |
Foldable (URec Word :: * -> *) | |
Defined in Data.Foldable fold :: Monoid m => URec Word m -> m # foldMap :: Monoid m => (a -> m) -> URec Word a -> m # foldr :: (a -> b -> b) -> b -> URec Word a -> b # foldr' :: (a -> b -> b) -> b -> URec Word a -> b # foldl :: (b -> a -> b) -> b -> URec Word a -> b # foldl' :: (b -> a -> b) -> b -> URec Word a -> b # foldr1 :: (a -> a -> a) -> URec Word a -> a # foldl1 :: (a -> a -> a) -> URec Word a -> a # toList :: URec Word a -> [a] # length :: URec Word a -> Int # elem :: Eq a => a -> URec Word a -> Bool # maximum :: Ord a => URec Word a -> a # minimum :: Ord a => URec Word a -> a # | |
Foldable (URec (Ptr ()) :: * -> *) | |
Defined in Data.Foldable fold :: Monoid m => URec (Ptr ()) m -> m # foldMap :: Monoid m => (a -> m) -> URec (Ptr ()) a -> m # foldr :: (a -> b -> b) -> b -> URec (Ptr ()) a -> b # foldr' :: (a -> b -> b) -> b -> URec (Ptr ()) a -> b # foldl :: (b -> a -> b) -> b -> URec (Ptr ()) a -> b # foldl' :: (b -> a -> b) -> b -> URec (Ptr ()) a -> b # foldr1 :: (a -> a -> a) -> URec (Ptr ()) a -> a # foldl1 :: (a -> a -> a) -> URec (Ptr ()) a -> a # toList :: URec (Ptr ()) a -> [a] # null :: URec (Ptr ()) a -> Bool # length :: URec (Ptr ()) a -> Int # elem :: Eq a => a -> URec (Ptr ()) a -> Bool # maximum :: Ord a => URec (Ptr ()) a -> a # minimum :: Ord a => URec (Ptr ()) a -> a # | |
Foldable (Const m :: * -> *) | Since: base-4.7.0.0 |
Defined in Data.Functor.Const fold :: Monoid m0 => Const m m0 -> m0 # foldMap :: Monoid m0 => (a -> m0) -> Const m a -> m0 # foldr :: (a -> b -> b) -> b -> Const m a -> b # foldr' :: (a -> b -> b) -> b -> Const m a -> b # foldl :: (b -> a -> b) -> b -> Const m a -> b # foldl' :: (b -> a -> b) -> b -> Const m a -> b # foldr1 :: (a -> a -> a) -> Const m a -> a # foldl1 :: (a -> a -> a) -> Const m a -> a # elem :: Eq a => a -> Const m a -> Bool # maximum :: Ord a => Const m a -> a # minimum :: Ord a => Const m a -> a # | |
Foldable (K1 i c :: * -> *) | |
Defined in Data.Foldable fold :: Monoid m => K1 i c m -> m # foldMap :: Monoid m => (a -> m) -> K1 i c a -> m # foldr :: (a -> b -> b) -> b -> K1 i c a -> b # foldr' :: (a -> b -> b) -> b -> K1 i c a -> b # foldl :: (b -> a -> b) -> b -> K1 i c a -> b # foldl' :: (b -> a -> b) -> b -> K1 i c a -> b # foldr1 :: (a -> a -> a) -> K1 i c a -> a # foldl1 :: (a -> a -> a) -> K1 i c a -> a # elem :: Eq a => a -> K1 i c a -> Bool # maximum :: Ord a => K1 i c a -> a # minimum :: Ord a => K1 i c a -> a # | |
(Foldable f, Foldable g) => Foldable (f :+: g) | |
Defined in Data.Foldable fold :: Monoid m => (f :+: g) m -> m # foldMap :: Monoid m => (a -> m) -> (f :+: g) a -> m # foldr :: (a -> b -> b) -> b -> (f :+: g) a -> b # foldr' :: (a -> b -> b) -> b -> (f :+: g) a -> b # foldl :: (b -> a -> b) -> b -> (f :+: g) a -> b # foldl' :: (b -> a -> b) -> b -> (f :+: g) a -> b # foldr1 :: (a -> a -> a) -> (f :+: g) a -> a # foldl1 :: (a -> a -> a) -> (f :+: g) a -> a # toList :: (f :+: g) a -> [a] # length :: (f :+: g) a -> Int # elem :: Eq a => a -> (f :+: g) a -> Bool # maximum :: Ord a => (f :+: g) a -> a # minimum :: Ord a => (f :+: g) a -> a # | |
(Foldable f, Foldable g) => Foldable (f :*: g) | |
Defined in Data.Foldable fold :: Monoid m => (f :*: g) m -> m # foldMap :: Monoid m => (a -> m) -> (f :*: g) a -> m # foldr :: (a -> b -> b) -> b -> (f :*: g) a -> b # foldr' :: (a -> b -> b) -> b -> (f :*: g) a -> b # foldl :: (b -> a -> b) -> b -> (f :*: g) a -> b # foldl' :: (b -> a -> b) -> b -> (f :*: g) a -> b # foldr1 :: (a -> a -> a) -> (f :*: g) a -> a # foldl1 :: (a -> a -> a) -> (f :*: g) a -> a # toList :: (f :*: g) a -> [a] # length :: (f :*: g) a -> Int # elem :: Eq a => a -> (f :*: g) a -> Bool # maximum :: Ord a => (f :*: g) a -> a # minimum :: Ord a => (f :*: g) a -> a # | |
Foldable f => Foldable (M1 i c f) | |
Defined in Data.Foldable fold :: Monoid m => M1 i c f m -> m # foldMap :: Monoid m => (a -> m) -> M1 i c f a -> m # foldr :: (a -> b -> b) -> b -> M1 i c f a -> b # foldr' :: (a -> b -> b) -> b -> M1 i c f a -> b # foldl :: (b -> a -> b) -> b -> M1 i c f a -> b # foldl' :: (b -> a -> b) -> b -> M1 i c f a -> b # foldr1 :: (a -> a -> a) -> M1 i c f a -> a # foldl1 :: (a -> a -> a) -> M1 i c f a -> a # elem :: Eq a => a -> M1 i c f a -> Bool # maximum :: Ord a => M1 i c f a -> a # minimum :: Ord a => M1 i c f a -> a # | |
(Foldable f, Foldable g) => Foldable (f :.: g) | |
Defined in Data.Foldable fold :: Monoid m => (f :.: g) m -> m # foldMap :: Monoid m => (a -> m) -> (f :.: g) a -> m # foldr :: (a -> b -> b) -> b -> (f :.: g) a -> b # foldr' :: (a -> b -> b) -> b -> (f :.: g) a -> b # foldl :: (b -> a -> b) -> b -> (f :.: g) a -> b # foldl' :: (b -> a -> b) -> b -> (f :.: g) a -> b # foldr1 :: (a -> a -> a) -> (f :.: g) a -> a # foldl1 :: (a -> a -> a) -> (f :.: g) a -> a # toList :: (f :.: g) a -> [a] # length :: (f :.: g) a -> Int # elem :: Eq a => a -> (f :.: g) a -> Bool # maximum :: Ord a => (f :.: g) a -> a # minimum :: Ord a => (f :.: g) a -> a # |
foldr' :: Foldable t => (a -> b -> b) -> b -> t a -> b #
Right-associative fold of a structure, but with strict application of the operator.
foldl' :: Foldable t => (b -> a -> b) -> b -> t a -> b #
Left-associative fold of a structure but with strict application of the operator.
This ensures that each step of the fold is forced to weak head normal
form before being applied, avoiding the collection of thunks that would
otherwise occur. This is often what you want to strictly reduce a finite
list to a single, monolithic result (e.g. length
).
For a general Foldable
structure this should be semantically identical
to,
foldl f z =foldl'
f z .toList
product :: (Foldable t, Num a) => t a -> a #
The product
function computes the product of the numbers of a
structure.
sum :: (Foldable t, Num a) => t a -> a #
The sum
function computes the sum of the numbers of a structure.
class (Functor t, Foldable t) => Traversable (t :: * -> *) where #
Functors representing data structures that can be traversed from left to right.
A definition of traverse
must satisfy the following laws:
- naturality
t .
for every applicative transformationtraverse
f =traverse
(t . f)t
- identity
traverse
Identity = Identity- composition
traverse
(Compose .fmap
g . f) = Compose .fmap
(traverse
g) .traverse
f
A definition of sequenceA
must satisfy the following laws:
- naturality
t .
for every applicative transformationsequenceA
=sequenceA
.fmap
tt
- identity
sequenceA
.fmap
Identity = Identity- composition
sequenceA
.fmap
Compose = Compose .fmap
sequenceA
.sequenceA
where an applicative transformation is a function
t :: (Applicative f, Applicative g) => f a -> g a
preserving the Applicative
operations, i.e.
and the identity functor Identity
and composition of functors Compose
are defined as
newtype Identity a = Identity a instance Functor Identity where fmap f (Identity x) = Identity (f x) instance Applicative Identity where pure x = Identity x Identity f <*> Identity x = Identity (f x) newtype Compose f g a = Compose (f (g a)) instance (Functor f, Functor g) => Functor (Compose f g) where fmap f (Compose x) = Compose (fmap (fmap f) x) instance (Applicative f, Applicative g) => Applicative (Compose f g) where pure x = Compose (pure (pure x)) Compose f <*> Compose x = Compose ((<*>) <$> f <*> x)
(The naturality law is implied by parametricity.)
Instances are similar to Functor
, e.g. given a data type
data Tree a = Empty | Leaf a | Node (Tree a) a (Tree a)
a suitable instance would be
instance Traversable Tree where traverse f Empty = pure Empty traverse f (Leaf x) = Leaf <$> f x traverse f (Node l k r) = Node <$> traverse f l <*> f k <*> traverse f r
This is suitable even for abstract types, as the laws for <*>
imply a form of associativity.
The superclass instances should satisfy the following:
- In the
Functor
instance,fmap
should be equivalent to traversal with the identity applicative functor (fmapDefault
). - In the
Foldable
instance,foldMap
should be equivalent to traversal with a constant applicative functor (foldMapDefault
).
traverse :: Applicative f => (a -> f b) -> t a -> f (t b) #
Map each element of a structure to an action, evaluate these actions
from left to right, and collect the results. For a version that ignores
the results see traverse_
.
sequenceA :: Applicative f => t (f a) -> f (t a) #
Evaluate each action in the structure from left to right, and
and collect the results. For a version that ignores the results
see sequenceA_
.
mapM :: Monad m => (a -> m b) -> t a -> m (t b) #
Map each element of a structure to a monadic action, evaluate
these actions from left to right, and collect the results. For
a version that ignores the results see mapM_
.
sequence :: Monad m => t (m a) -> m (t a) #
Evaluate each monadic action in the structure from left to
right, and collect the results. For a version that ignores the
results see sequence_
.
Instances
any :: Foldable t => (a -> Bool) -> t a -> Bool #
Determines whether any element of the structure satisfies the predicate.
all :: Foldable t => (a -> Bool) -> t a -> Bool #
Determines whether all elements of the structure satisfy the predicate.
concat :: Foldable t => t [a] -> [a] #
The concatenation of all the elements of a container of lists.
concatMap :: Foldable t => (a -> [b]) -> t a -> [b] #
Map a function over all the elements of a container and concatenate the resulting lists.
asum :: (Foldable t, Alternative f) => t (f a) -> f a #
sequenceA_ :: (Foldable t, Applicative f) => t (f a) -> f () #
Evaluate each action in the structure from left to right, and
ignore the results. For a version that doesn't ignore the results
see sequenceA
.
traverse_ :: (Foldable t, Applicative f) => (a -> f b) -> t a -> f () #
Map each element of a structure to an action, evaluate these
actions from left to right, and ignore the results. For a version
that doesn't ignore the results see traverse
.
null :: Foldable t => t a -> Bool #
Test whether the structure is empty. The default implementation is optimized for structures that are similar to cons-lists, because there is no general way to do better.
length :: Foldable t => t a -> Int #
Returns the size/length of a finite structure as an Int
. The
default implementation is optimized for structures that are similar to
cons-lists, because there is no general way to do better.
Data
, Typeable
, and Generic
The Data
class comprehends a fundamental primitive gfoldl
for
folding over constructor applications, say terms. This primitive can
be instantiated in several ways to map over the immediate subterms
of a term; see the gmap
combinators later in this class. Indeed, a
generic programmer does not necessarily need to use the ingenious gfoldl
primitive but rather the intuitive gmap
combinators. The gfoldl
primitive is completed by means to query top-level constructors, to
turn constructor representations into proper terms, and to list all
possible datatype constructors. This completion allows us to serve
generic programming scenarios like read, show, equality, term generation.
The combinators gmapT
, gmapQ
, gmapM
, etc are all provided with
default definitions in terms of gfoldl
, leaving open the opportunity
to provide datatype-specific definitions.
(The inclusion of the gmap
combinators as members of class Data
allows the programmer or the compiler to derive specialised, and maybe
more efficient code per datatype. Note: gfoldl
is more higher-order
than the gmap
combinators. This is subject to ongoing benchmarking
experiments. It might turn out that the gmap
combinators will be
moved out of the class Data
.)
Conceptually, the definition of the gmap
combinators in terms of the
primitive gfoldl
requires the identification of the gfoldl
function
arguments. Technically, we also need to identify the type constructor
c
for the construction of the result type from the folded term type.
In the definition of gmapQ
x combinators, we use phantom type
constructors for the c
in the type of gfoldl
because the result type
of a query does not involve the (polymorphic) type of the term argument.
In the definition of gmapQl
we simply use the plain constant type
constructor because gfoldl
is left-associative anyway and so it is
readily suited to fold a left-associative binary operation over the
immediate subterms. In the definition of gmapQr, extra effort is
needed. We use a higher-order accumulation trick to mediate between
left-associative constructor application vs. right-associative binary
operation (e.g., (:)
). When the query is meant to compute a value
of type r
, then the result type withing generic folding is r -> r
.
So the result of folding is a function to which we finally pass the
right unit.
With the -XDeriveDataTypeable
option, GHC can generate instances of the
Data
class automatically. For example, given the declaration
data T a b = C1 a b | C2 deriving (Typeable, Data)
GHC will generate an instance that is equivalent to
instance (Data a, Data b) => Data (T a b) where gfoldl k z (C1 a b) = z C1 `k` a `k` b gfoldl k z C2 = z C2 gunfold k z c = case constrIndex c of 1 -> k (k (z C1)) 2 -> z C2 toConstr (C1 _ _) = con_C1 toConstr C2 = con_C2 dataTypeOf _ = ty_T con_C1 = mkConstr ty_T "C1" [] Prefix con_C2 = mkConstr ty_T "C2" [] Prefix ty_T = mkDataType "Module.T" [con_C1, con_C2]
This is suitable for datatypes that are exported transparently.
Instances
Data Bool | Since: base-4.0.0.0 |
Defined in Data.Data gfoldl :: (forall d b. Data d => c (d -> b) -> d -> c b) -> (forall g. g -> c g) -> Bool -> c Bool # gunfold :: (forall b r. Data b => c (b -> r) -> c r) -> (forall r. r -> c r) -> Constr -> c Bool # dataTypeOf :: Bool -> DataType # dataCast1 :: Typeable t => (forall d. Data d => c (t d)) -> Maybe (c Bool) # dataCast2 :: Typeable t => (forall d e. (Data d, Data e) => c (t d e)) -> Maybe (c Bool) # gmapT :: (forall b. Data b => b -> b) -> Bool -> Bool # gmapQl :: (r -> r' -> r) -> r -> (forall d. Data d => d -> r') -> Bool -> r # gmapQr :: (r' -> r -> r) -> r -> (forall d. Data d => d -> r') -> Bool -> r # gmapQ :: (forall d. Data d => d -> u) -> Bool -> [u] # gmapQi :: Int -> (forall d. Data d => d -> u) -> Bool -> u # gmapM :: Monad m => (forall d. Data d => d -> m d) -> Bool -> m Bool # gmapMp :: MonadPlus m => (forall d. Data d => d -> m d) -> Bool -> m Bool # gmapMo :: MonadPlus m => (forall d. Data d => d -> m d) -> Bool -> m Bool # | |
Data Char | Since: base-4.0.0.0 |
Defined in Data.Data gfoldl :: (forall d b. Data d => c (d -> b) -> d -> c b) -> (forall g. g -> c g) -> Char -> c Char # gunfold :: (forall b r. Data b => c (b -> r) -> c r) -> (forall r. r -> c r) -> Constr -> c Char # dataTypeOf :: Char -> DataType # dataCast1 :: Typeable t => (forall d. Data d => c (t d)) -> Maybe (c Char) # dataCast2 :: Typeable t => (forall d e. (Data d, Data e) => c (t d e)) -> Maybe (c Char) # gmapT :: (forall b. Data b => b -> b) -> Char -> Char # gmapQl :: (r -> r' -> r) -> r -> (forall d. Data d => d -> r') -> Char -> r # gmapQr :: (r' -> r -> r) -> r -> (forall d. Data d => d -> r') -> Char -> r # gmapQ :: (forall d. Data d => d -> u) -> Char -> [u] # gmapQi :: Int -> (forall d. Data d => d -> u) -> Char -> u # gmapM :: Monad m => (forall d. Data d => d -> m d) -> Char -> m Char # gmapMp :: MonadPlus m => (forall d. Data d => d -> m d) -> Char -> m Char # gmapMo :: MonadPlus m => (forall d. Data d => d -> m d) -> Char -> m Char # | |
Data Double | Since: base-4.0.0.0 |
Defined in Data.Data gfoldl :: (forall d b. Data d => c (d -> b) -> d -> c b) -> (forall g. g -> c g) -> Double -> c Double # gunfold :: (forall b r. Data b => c (b -> r) -> c r) -> (forall r. r -> c r) -> Constr -> c Double # toConstr :: Double -> Constr # dataTypeOf :: Double -> DataType # dataCast1 :: Typeable t => (forall d. Data d => c (t d)) -> Maybe (c Double) # dataCast2 :: Typeable t => (forall d e. (Data d, Data e) => c (t d e)) -> Maybe (c Double) # gmapT :: (forall b. Data b => b -> b) -> Double -> Double # gmapQl :: (r -> r' -> r) -> r -> (forall d. Data d => d -> r') -> Double -> r # gmapQr :: (r' -> r -> r) -> r -> (forall d. Data d => d -> r') -> Double -> r # gmapQ :: (forall d. Data d => d -> u) -> Double -> [u] # gmapQi :: Int -> (forall d. Data d => d -> u) -> Double -> u # gmapM :: Monad m => (forall d. Data d => d -> m d) -> Double -> m Double # gmapMp :: MonadPlus m => (forall d. Data d => d -> m d) -> Double -> m Double # gmapMo :: MonadPlus m => (forall d. Data d => d -> m d) -> Double -> m Double # | |
Data Float | Since: base-4.0.0.0 |
Defined in Data.Data gfoldl :: (forall d b. Data d => c (d -> b) -> d -> c b) -> (forall g. g -> c g) -> Float -> c Float # gunfold :: (forall b r. Data b => c (b -> r) -> c r) -> (forall r. r -> c r) -> Constr -> c Float # dataTypeOf :: Float -> DataType # dataCast1 :: Typeable t => (forall d. Data d => c (t d)) -> Maybe (c Float) # dataCast2 :: Typeable t => (forall d e. (Data d, Data e) => c (t d e)) -> Maybe (c Float) # gmapT :: (forall b. Data b => b -> b) -> Float -> Float # gmapQl :: (r -> r' -> r) -> r -> (forall d. Data d => d -> r') -> Float -> r # gmapQr :: (r' -> r -> r) -> r -> (forall d. Data d => d -> r') -> Float -> r # gmapQ :: (forall d. Data d => d -> u) -> Float -> [u] # gmapQi :: Int -> (forall d. Data d => d -> u) -> Float -> u # gmapM :: Monad m => (forall d. Data d => d -> m d) -> Float -> m Float # gmapMp :: MonadPlus m => (forall d. Data d => d -> m d) -> Float -> m Float # gmapMo :: MonadPlus m => (forall d. Data d => d -> m d) -> Float -> m Float # | |
Data Int | Since: base-4.0.0.0 |
Defined in Data.Data gfoldl :: (forall d b. Data d => c (d -> b) -> d -> c b) -> (forall g. g -> c g) -> Int -> c Int # gunfold :: (forall b r. Data b => c (b -> r) -> c r) -> (forall r. r -> c r) -> Constr -> c Int # dataTypeOf :: Int -> DataType # dataCast1 :: Typeable t => (forall d. Data d => c (t d)) -> Maybe (c Int) # dataCast2 :: Typeable t => (forall d e. (Data d, Data e) => c (t d e)) -> Maybe (c Int) # gmapT :: (forall b. Data b => b -> b) -> Int -> Int # gmapQl :: (r -> r' -> r) -> r -> (forall d. Data d => d -> r') -> Int -> r # gmapQr :: (r' -> r -> r) -> r -> (forall d. Data d => d -> r') -> Int -> r # gmapQ :: (forall d. Data d => d -> u) -> Int -> [u] # gmapQi :: Int -> (forall d. Data d => d -> u) -> Int -> u # gmapM :: Monad m => (forall d. Data d => d -> m d) -> Int -> m Int # gmapMp :: MonadPlus m => (forall d. Data d => d -> m d) -> Int -> m Int # gmapMo :: MonadPlus m => (forall d. Data d => d -> m d) -> Int -> m Int # | |
Data Int8 | Since: base-4.0.0.0 |
Defined in Data.Data gfoldl :: (forall d b. Data d => c (d -> b) -> d -> c b) -> (forall g. g -> c g) -> Int8 -> c Int8 # gunfold :: (forall b r. Data b => c (b -> r) -> c r) -> (forall r. r -> c r) -> Constr -> c Int8 # dataTypeOf :: Int8 -> DataType # dataCast1 :: Typeable t => (forall d. Data d => c (t d)) -> Maybe (c Int8) # dataCast2 :: Typeable t => (forall d e. (Data d, Data e) => c (t d e)) -> Maybe (c Int8) # gmapT :: (forall b. Data b => b -> b) -> Int8 -> Int8 # gmapQl :: (r -> r' -> r) -> r -> (forall d. Data d => d -> r') -> Int8 -> r # gmapQr :: (r' -> r -> r) -> r -> (forall d. Data d => d -> r') -> Int8 -> r # gmapQ :: (forall d. Data d => d -> u) -> Int8 -> [u] # gmapQi :: Int -> (forall d. Data d => d -> u) -> Int8 -> u # gmapM :: Monad m => (forall d. Data d => d -> m d) -> Int8 -> m Int8 # gmapMp :: MonadPlus m => (forall d. Data d => d -> m d) -> Int8 -> m Int8 # gmapMo :: MonadPlus m => (forall d. Data d => d -> m d) -> Int8 -> m Int8 # | |
Data Int16 | Since: base-4.0.0.0 |
Defined in Data.Data gfoldl :: (forall d b. Data d => c (d -> b) -> d -> c b) -> (forall g. g -> c g) -> Int16 -> c Int16 # gunfold :: (forall b r. Data b => c (b -> r) -> c r) -> (forall r. r -> c r) -> Constr -> c Int16 # dataTypeOf :: Int16 -> DataType # dataCast1 :: Typeable t => (forall d. Data d => c (t d)) -> Maybe (c Int16) # dataCast2 :: Typeable t => (forall d e. (Data d, Data e) => c (t d e)) -> Maybe (c Int16) # gmapT :: (forall b. Data b => b -> b) -> Int16 -> Int16 # gmapQl :: (r -> r' -> r) -> r -> (forall d. Data d => d -> r') -> Int16 -> r # gmapQr :: (r' -> r -> r) -> r -> (forall d. Data d => d -> r') -> Int16 -> r # gmapQ :: (forall d. Data d => d -> u) -> Int16 -> [u] # gmapQi :: Int -> (forall d. Data d => d -> u) -> Int16 -> u # gmapM :: Monad m => (forall d. Data d => d -> m d) -> Int16 -> m Int16 # gmapMp :: MonadPlus m => (forall d. Data d => d -> m d) -> Int16 -> m Int16 # gmapMo :: MonadPlus m => (forall d. Data d => d -> m d) -> Int16 -> m Int16 # | |
Data Int32 | Since: base-4.0.0.0 |
Defined in Data.Data gfoldl :: (forall d b. Data d => c (d -> b) -> d -> c b) -> (forall g. g -> c g) -> Int32 -> c Int32 # gunfold :: (forall b r. Data b => c (b -> r) -> c r) -> (forall r. r -> c r) -> Constr -> c Int32 # dataTypeOf :: Int32 -> DataType # dataCast1 :: Typeable t => (forall d. Data d => c (t d)) -> Maybe (c Int32) # dataCast2 :: Typeable t => (forall d e. (Data d, Data e) => c (t d e)) -> Maybe (c Int32) # gmapT :: (forall b. Data b => b -> b) -> Int32 -> Int32 # gmapQl :: (r -> r' -> r) -> r -> (forall d. Data d => d -> r') -> Int32 -> r # gmapQr :: (r' -> r -> r) -> r -> (forall d. Data d => d -> r') -> Int32 -> r # gmapQ :: (forall d. Data d => d -> u) -> Int32 -> [u] # gmapQi :: Int -> (forall d. Data d => d -> u) -> Int32 -> u # gmapM :: Monad m => (forall d. Data d => d -> m d) -> Int32 -> m Int32 # gmapMp :: MonadPlus m => (forall d. Data d => d -> m d) -> Int32 -> m Int32 # gmapMo :: MonadPlus m => (forall d. Data d => d -> m d) -> Int32 -> m Int32 # | |
Data Int64 | Since: base-4.0.0.0 |
Defined in Data.Data gfoldl :: (forall d b. Data d => c (d -> b) -> d -> c b) -> (forall g. g -> c g) -> Int64 -> c Int64 # gunfold :: (forall b r. Data b => c (b -> r) -> c r) -> (forall r. r -> c r) -> Constr -> c Int64 # dataTypeOf :: Int64 -> DataType # dataCast1 :: Typeable t => (forall d. Data d => c (t d)) -> Maybe (c Int64) # dataCast2 :: Typeable t => (forall d e. (Data d, Data e) => c (t d e)) -> Maybe (c Int64) # gmapT :: (forall b. Data b => b -> b) -> Int64 -> Int64 # gmapQl :: (r -> r' -> r) -> r -> (forall d. Data d => d -> r') -> Int64 -> r # gmapQr :: (r' -> r -> r) -> r -> (forall d. Data d => d -> r') -> Int64 -> r # gmapQ :: (forall d. Data d => d -> u) -> Int64 -> [u] # gmapQi :: Int -> (forall d. Data d => d -> u) -> Int64 -> u # gmapM :: Monad m => (forall d. Data d => d -> m d) -> Int64 -> m Int64 # gmapMp :: MonadPlus m => (forall d. Data d => d -> m d) -> Int64 -> m Int64 # gmapMo :: MonadPlus m => (forall d. Data d => d -> m d) -> Int64 -> m Int64 # | |
Data Integer | Since: base-4.0.0.0 |
Defined in Data.Data gfoldl :: (forall d b. Data d => c (d -> b) -> d -> c b) -> (forall g. g -> c g) -> Integer -> c Integer # gunfold :: (forall b r. Data b => c (b -> r) -> c r) -> (forall r. r -> c r) -> Constr -> c Integer # toConstr :: Integer -> Constr # dataTypeOf :: Integer -> DataType # dataCast1 :: Typeable t => (forall d. Data d => c (t d)) -> Maybe (c Integer) # dataCast2 :: Typeable t => (forall d e. (Data d, Data e) => c (t d e)) -> Maybe (c Integer) # gmapT :: (forall b. Data b => b -> b) -> Integer -> Integer # gmapQl :: (r -> r' -> r) -> r -> (forall d. Data d => d -> r') -> Integer -> r # gmapQr :: (r' -> r -> r) -> r -> (forall d. Data d => d -> r') -> Integer -> r # gmapQ :: (forall d. Data d => d -> u) -> Integer -> [u] # gmapQi :: Int -> (forall d. Data d => d -> u) -> Integer -> u # gmapM :: Monad m => (forall d. Data d => d -> m d) -> Integer -> m Integer # gmapMp :: MonadPlus m => (forall d. Data d => d -> m d) -> Integer -> m Integer # gmapMo :: MonadPlus m => (forall d. Data d => d -> m d) -> Integer -> m Integer # | |
Data Natural | Since: base-4.8.0.0 |
Defined in Data.Data gfoldl :: (forall d b. Data d => c (d -> b) -> d -> c b) -> (forall g. g -> c g) -> Natural -> c Natural # gunfold :: (forall b r. Data b => c (b -> r) -> c r) -> (forall r. r -> c r) -> Constr -> c Natural # toConstr :: Natural -> Constr # dataTypeOf :: Natural -> DataType # dataCast1 :: Typeable t => (forall d. Data d => c (t d)) -> Maybe (c Natural) # dataCast2 :: Typeable t => (forall d e. (Data d, Data e) => c (t d e)) -> Maybe (c Natural) # gmapT :: (forall b. Data b => b -> b) -> Natural -> Natural # gmapQl :: (r -> r' -> r) -> r -> (forall d. Data d => d -> r') -> Natural -> r # gmapQr :: (r' -> r -> r) -> r -> (forall d. Data d => d -> r') -> Natural -> r # gmapQ :: (forall d. Data d => d -> u) -> Natural -> [u] # gmapQi :: Int -> (forall d. Data d => d -> u) -> Natural -> u # gmapM :: Monad m => (forall d. Data d => d -> m d) -> Natural -> m Natural # gmapMp :: MonadPlus m => (forall d. Data d => d -> m d) -> Natural -> m Natural # gmapMo :: MonadPlus m => (forall d. Data d => d -> m d) -> Natural -> m Natural # | |
Data Ordering | Since: base-4.0.0.0 |
Defined in Data.Data gfoldl :: (forall d b. Data d => c (d -> b) -> d -> c b) -> (forall g. g -> c g) -> Ordering -> c Ordering # gunfold :: (forall b r. Data b => c (b -> r) -> c r) -> (forall r. r -> c r) -> Constr -> c Ordering # toConstr :: Ordering -> Constr # dataTypeOf :: Ordering -> DataType # dataCast1 :: Typeable t => (forall d. Data d => c (t d)) -> Maybe (c Ordering) # dataCast2 :: Typeable t => (forall d e. (Data d, Data e) => c (t d e)) -> Maybe (c Ordering) # gmapT :: (forall b. Data b => b -> b) -> Ordering -> Ordering # gmapQl :: (r -> r' -> r) -> r -> (forall d. Data d => d -> r') -> Ordering -> r # gmapQr :: (r' -> r -> r) -> r -> (forall d. Data d => d -> r') -> Ordering -> r # gmapQ :: (forall d. Data d => d -> u) -> Ordering -> [u] # gmapQi :: Int -> (forall d. Data d => d -> u) -> Ordering -> u # gmapM :: Monad m => (forall d. Data d => d -> m d) -> Ordering -> m Ordering # gmapMp :: MonadPlus m => (forall d. Data d => d -> m d) -> Ordering -> m Ordering # gmapMo :: MonadPlus m => (forall d. Data d => d -> m d) -> Ordering -> m Ordering # | |
Data Word | Since: base-4.0.0.0 |
Defined in Data.Data gfoldl :: (forall d b. Data d => c (d -> b) -> d -> c b) -> (forall g. g -> c g) -> Word -> c Word # gunfold :: (forall b r. Data b => c (b -> r) -> c r) -> (forall r. r -> c r) -> Constr -> c Word # dataTypeOf :: Word -> DataType # dataCast1 :: Typeable t => (forall d. Data d => c (t d)) -> Maybe (c Word) # dataCast2 :: Typeable t => (forall d e. (Data d, Data e) => c (t d e)) -> Maybe (c Word) # gmapT :: (forall b. Data b => b -> b) -> Word -> Word # gmapQl :: (r -> r' -> r) -> r -> (forall d. Data d => d -> r') -> Word -> r # gmapQr :: (r' -> r -> r) -> r -> (forall d. Data d => d -> r') -> Word -> r # gmapQ :: (forall d. Data d => d -> u) -> Word -> [u] # gmapQi :: Int -> (forall d. Data d => d -> u) -> Word -> u # gmapM :: Monad m => (forall d. Data d => d -> m d) -> Word -> m Word # gmapMp :: MonadPlus m => (forall d. Data d => d -> m d) -> Word -> m Word # gmapMo :: MonadPlus m => (forall d. Data d => d -> m d) -> Word -> m Word # | |
Data Word8 | Since: base-4.0.0.0 |
Defined in Data.Data gfoldl :: (forall d b. Data d => c (d -> b) -> d -> c b) -> (forall g. g -> c g) -> Word8 -> c Word8 # gunfold :: (forall b r. Data b => c (b -> r) -> c r) -> (forall r. r -> c r) -> Constr -> c Word8 # dataTypeOf :: Word8 -> DataType # dataCast1 :: Typeable t => (forall d. Data d => c (t d)) -> Maybe (c Word8) # dataCast2 :: Typeable t => (forall d e. (Data d, Data e) => c (t d e)) -> Maybe (c Word8) # gmapT :: (forall b. Data b => b -> b) -> Word8 -> Word8 # gmapQl :: (r -> r' -> r) -> r -> (forall d. Data d => d -> r') -> Word8 -> r # gmapQr :: (r' -> r -> r) -> r -> (forall d. Data d => d -> r') -> Word8 -> r # gmapQ :: (forall d. Data d => d -> u) -> Word8 -> [u] # gmapQi :: Int -> (forall d. Data d => d -> u) -> Word8 -> u # gmapM :: Monad m => (forall d. Data d => d -> m d) -> Word8 -> m Word8 # gmapMp :: MonadPlus m => (forall d. Data d => d -> m d) -> Word8 -> m Word8 # gmapMo :: MonadPlus m => (forall d. Data d => d -> m d) -> Word8 -> m Word8 # | |
Data Word16 | Since: base-4.0.0.0 |
Defined in Data.Data gfoldl :: (forall d b. Data d => c (d -> b) -> d -> c b) -> (forall g. g -> c g) -> Word16 -> c Word16 # gunfold :: (forall b r. Data b => c (b -> r) -> c r) -> (forall r. r -> c r) -> Constr -> c Word16 # toConstr :: Word16 -> Constr # dataTypeOf :: Word16 -> DataType # dataCast1 :: Typeable t => (forall d. Data d => c (t d)) -> Maybe (c Word16) # dataCast2 :: Typeable t => (forall d e. (Data d, Data e) => c (t d e)) -> Maybe (c Word16) # gmapT :: (forall b. Data b => b -> b) -> Word16 -> Word16 # gmapQl :: (r -> r' -> r) -> r -> (forall d. Data d => d -> r') -> Word16 -> r # gmapQr :: (r' -> r -> r) -> r -> (forall d. Data d => d -> r') -> Word16 -> r # gmapQ :: (forall d. Data d => d -> u) -> Word16 -> [u] # gmapQi :: Int -> (forall d. Data d => d -> u) -> Word16 -> u # gmapM :: Monad m => (forall d. Data d => d -> m d) -> Word16 -> m Word16 # gmapMp :: MonadPlus m => (forall d. Data d => d -> m d) -> Word16 -> m Word16 # gmapMo :: MonadPlus m => (forall d. Data d => d -> m d) -> Word16 -> m Word16 # | |
Data Word32 | Since: base-4.0.0.0 |
Defined in Data.Data gfoldl :: (forall d b. Data d => c (d -> b) -> d -> c b) -> (forall g. g -> c g) -> Word32 -> c Word32 # gunfold :: (forall b r. Data b => c (b -> r) -> c r) -> (forall r. r -> c r) -> Constr -> c Word32 # toConstr :: Word32 -> Constr # dataTypeOf :: Word32 -> DataType # dataCast1 :: Typeable t => (forall d. Data d => c (t d)) -> Maybe (c Word32) # dataCast2 :: Typeable t => (forall d e. (Data d, Data e) => c (t d e)) -> Maybe (c Word32) # gmapT :: (forall b. Data b => b -> b) -> Word32 -> Word32 # gmapQl :: (r -> r' -> r) -> r -> (forall d. Data d => d -> r') -> Word32 -> r # gmapQr :: (r' -> r -> r) -> r -> (forall d. Data d => d -> r') -> Word32 -> r # gmapQ :: (forall d. Data d => d -> u) -> Word32 -> [u] # gmapQi :: Int -> (forall d. Data d => d -> u) -> Word32 -> u # gmapM :: Monad m => (forall d. Data d => d -> m d) -> Word32 -> m Word32 # gmapMp :: MonadPlus m => (forall d. Data d => d -> m d) -> Word32 -> m Word32 # gmapMo :: MonadPlus m => (forall d. Data d => d -> m d) -> Word32 -> m Word32 # | |
Data Word64 | Since: base-4.0.0.0 |
Defined in Data.Data gfoldl :: (forall d b. Data d => c (d -> b) -> d -> c b) -> (forall g. g -> c g) -> Word64 -> c Word64 # gunfold :: (forall b r. Data b => c (b -> r) -> c r) -> (forall r. r -> c r) -> Constr -> c Word64 # toConstr :: Word64 -> Constr # dataTypeOf :: Word64 -> DataType # dataCast1 :: Typeable t => (forall d. Data d => c (t d)) -> Maybe (c Word64) # dataCast2 :: Typeable t => (forall d e. (Data d, Data e) => c (t d e)) -> Maybe (c Word64) # gmapT :: (forall b. Data b => b -> b) -> Word64 -> Word64 # gmapQl :: (r -> r' -> r) -> r -> (forall d. Data d => d -> r') -> Word64 -> r # gmapQr :: (r' -> r -> r) -> r -> (forall d. Data d => d -> r') -> Word64 -> r # gmapQ :: (forall d. Data d => d -> u) -> Word64 -> [u] # gmapQi :: Int -> (forall d. Data d => d -> u) -> Word64 -> u # gmapM :: Monad m => (forall d. Data d => d -> m d) -> Word64 -> m Word64 # gmapMp :: MonadPlus m => (forall d. Data d => d -> m d) -> Word64 -> m Word64 # gmapMo :: MonadPlus m => (forall d. Data d => d -> m d) -> Word64 -> m Word64 # | |
Data () | Since: base-4.0.0.0 |
Defined in Data.Data gfoldl :: (forall d b. Data d => c (d -> b) -> d -> c b) -> (forall g. g -> c g) -> () -> c () # gunfold :: (forall b r. Data b => c (b -> r) -> c r) -> (forall r. r -> c r) -> Constr -> c () # dataTypeOf :: () -> DataType # dataCast1 :: Typeable t => (forall d. Data d => c (t d)) -> Maybe (c ()) # dataCast2 :: Typeable t => (forall d e. (Data d, Data e) => c (t d e)) -> Maybe (c ()) # gmapT :: (forall b. Data b => b -> b) -> () -> () # gmapQl :: (r -> r' -> r) -> r -> (forall d. Data d => d -> r') -> () -> r # gmapQr :: (r' -> r -> r) -> r -> (forall d. Data d => d -> r') -> () -> r # gmapQ :: (forall d. Data d => d -> u) -> () -> [u] # gmapQi :: Int -> (forall d. Data d => d -> u) -> () -> u # gmapM :: Monad m => (forall d. Data d => d -> m d) -> () -> m () # gmapMp :: MonadPlus m => (forall d. Data d => d -> m d) -> () -> m () # gmapMo :: MonadPlus m => (forall d. Data d => d -> m d) -> () -> m () # | |
Data Version | Since: base-4.7.0.0 |
Defined in Data.Data gfoldl :: (forall d b. Data d => c (d -> b) -> d -> c b) -> (forall g. g -> c g) -> Version -> c Version # gunfold :: (forall b r. Data b => c (b -> r) -> c r) -> (forall r. r -> c r) -> Constr -> c Version # toConstr :: Version -> Constr # dataTypeOf :: Version -> DataType # dataCast1 :: Typeable t => (forall d. Data d => c (t d)) -> Maybe (c Version) # dataCast2 :: Typeable t => (forall d e. (Data d, Data e) => c (t d e)) -> Maybe (c Version) # gmapT :: (forall b. Data b => b -> b) -> Version -> Version # gmapQl :: (r -> r' -> r) -> r -> (forall d. Data d => d -> r') -> Version -> r # gmapQr :: (r' -> r -> r) -> r -> (forall d. Data d => d -> r') -> Version -> r # gmapQ :: (forall d. Data d => d -> u) -> Version -> [u] # gmapQi :: Int -> (forall d. Data d => d -> u) -> Version -> u # gmapM :: Monad m => (forall d. Data d => d -> m d) -> Version -> m Version # gmapMp :: MonadPlus m => (forall d. Data d => d -> m d) -> Version -> m Version # gmapMo :: MonadPlus m => (forall d. Data d => d -> m d) -> Version -> m Version # | |
Data All | Since: base-4.8.0.0 |
Defined in Data.Data gfoldl :: (forall d b. Data d => c (d -> b) -> d -> c b) -> (forall g. g -> c g) -> All -> c All # gunfold :: (forall b r. Data b => c (b -> r) -> c r) -> (forall r. r -> c r) -> Constr -> c All # dataTypeOf :: All -> DataType # dataCast1 :: Typeable t => (forall d. Data d => c (t d)) -> Maybe (c All) # dataCast2 :: Typeable t => (forall d e. (Data d, Data e) => c (t d e)) -> Maybe (c All) # gmapT :: (forall b. Data b => b -> b) -> All -> All # gmapQl :: (r -> r' -> r) -> r -> (forall d. Data d => d -> r') -> All -> r # gmapQr :: (r' -> r -> r) -> r -> (forall d. Data d => d -> r') -> All -> r # gmapQ :: (forall d. Data d => d -> u) -> All -> [u] # gmapQi :: Int -> (forall d. Data d => d -> u) -> All -> u # gmapM :: Monad m => (forall d. Data d => d -> m d) -> All -> m All # gmapMp :: MonadPlus m => (forall d. Data d => d -> m d) -> All -> m All # gmapMo :: MonadPlus m => (forall d. Data d => d -> m d) -> All -> m All # | |
Data Any | Since: base-4.8.0.0 |
Defined in Data.Data gfoldl :: (forall d b. Data d => c (d -> b) -> d -> c b) -> (forall g. g -> c g) -> Any -> c Any # gunfold :: (forall b r. Data b => c (b -> r) -> c r) -> (forall r. r -> c r) -> Constr -> c Any # dataTypeOf :: Any -> DataType # dataCast1 :: Typeable t => (forall d. Data d => c (t d)) -> Maybe (c Any) # dataCast2 :: Typeable t => (forall d e. (Data d, Data e) => c (t d e)) -> Maybe (c Any) # gmapT :: (forall b. Data b => b -> b) -> Any -> Any # gmapQl :: (r -> r' -> r) -> r -> (forall d. Data d => d -> r') -> Any -> r # gmapQr :: (r' -> r -> r) -> r -> (forall d. Data d => d -> r') -> Any -> r # gmapQ :: (forall d. Data d => d -> u) -> Any -> [u] # gmapQi :: Int -> (forall d. Data d => d -> u) -> Any -> u # gmapM :: Monad m => (forall d. Data d => d -> m d) -> Any -> m Any # gmapMp :: MonadPlus m => (forall d. Data d => d -> m d) -> Any -> m Any # gmapMo :: MonadPlus m => (forall d. Data d => d -> m d) -> Any -> m Any # | |
Data Fixity | Since: base-4.9.0.0 |
Defined in Data.Data gfoldl :: (forall d b. Data d => c (d -> b) -> d -> c b) -> (forall g. g -> c g) -> Fixity -> c Fixity # gunfold :: (forall b r. Data b => c (b -> r) -> c r) -> (forall r. r -> c r) -> Constr -> c Fixity # toConstr :: Fixity -> Constr # dataTypeOf :: Fixity -> DataType # dataCast1 :: Typeable t => (forall d. Data d => c (t d)) -> Maybe (c Fixity) # dataCast2 :: Typeable t => (forall d e. (Data d, Data e) => c (t d e)) -> Maybe (c Fixity) # gmapT :: (forall b. Data b => b -> b) -> Fixity -> Fixity # gmapQl :: (r -> r' -> r) -> r -> (forall d. Data d => d -> r') -> Fixity -> r # gmapQr :: (r' -> r -> r) -> r -> (forall d. Data d => d -> r') -> Fixity -> r # gmapQ :: (forall d. Data d => d -> u) -> Fixity -> [u] # gmapQi :: Int -> (forall d. Data d => d -> u) -> Fixity -> u # gmapM :: Monad m => (forall d. Data d => d -> m d) -> Fixity -> m Fixity # gmapMp :: MonadPlus m => (forall d. Data d => d -> m d) -> Fixity -> m Fixity # gmapMo :: MonadPlus m => (forall d. Data d => d -> m d) -> Fixity -> m Fixity # | |
Data Associativity | Since: base-4.9.0.0 |
Defined in Data.Data gfoldl :: (forall d b. Data d => c (d -> b) -> d -> c b) -> (forall g. g -> c g) -> Associativity -> c Associativity # gunfold :: (forall b r. Data b => c (b -> r) -> c r) -> (forall r. r -> c r) -> Constr -> c Associativity # toConstr :: Associativity -> Constr # dataTypeOf :: Associativity -> DataType # dataCast1 :: Typeable t => (forall d. Data d => c (t d)) -> Maybe (c Associativity) # dataCast2 :: Typeable t => (forall d e. (Data d, Data e) => c (t d e)) -> Maybe (c Associativity) # gmapT :: (forall b. Data b => b -> b) -> Associativity -> Associativity # gmapQl :: (r -> r' -> r) -> r -> (forall d. Data d => d -> r') -> Associativity -> r # gmapQr :: (r' -> r -> r) -> r -> (forall d. Data d => d -> r') -> Associativity -> r # gmapQ :: (forall d. Data d => d -> u) -> Associativity -> [u] # gmapQi :: Int -> (forall d. Data d => d -> u) -> Associativity -> u # gmapM :: Monad m => (forall d. Data d => d -> m d) -> Associativity -> m Associativity # gmapMp :: MonadPlus m => (forall d. Data d => d -> m d) -> Associativity -> m Associativity # gmapMo :: MonadPlus m => (forall d. Data d => d -> m d) -> Associativity -> m Associativity # | |
Data SourceUnpackedness | Since: base-4.9.0.0 |
Defined in Data.Data gfoldl :: (forall d b. Data d => c (d -> b) -> d -> c b) -> (forall g. g -> c g) -> SourceUnpackedness -> c SourceUnpackedness # gunfold :: (forall b r. Data b => c (b -> r) -> c r) -> (forall r. r -> c r) -> Constr -> c SourceUnpackedness # toConstr :: SourceUnpackedness -> Constr # dataTypeOf :: SourceUnpackedness -> DataType # dataCast1 :: Typeable t => (forall d. Data d => c (t d)) -> Maybe (c SourceUnpackedness) # dataCast2 :: Typeable t => (forall d e. (Data d, Data e) => c (t d e)) -> Maybe (c SourceUnpackedness) # gmapT :: (forall b. Data b => b -> b) -> SourceUnpackedness -> SourceUnpackedness # gmapQl :: (r -> r' -> r) -> r -> (forall d. Data d => d -> r') -> SourceUnpackedness -> r # gmapQr :: (r' -> r -> r) -> r -> (forall d. Data d => d -> r') -> SourceUnpackedness -> r # gmapQ :: (forall d. Data d => d -> u) -> SourceUnpackedness -> [u] # gmapQi :: Int -> (forall d. Data d => d -> u) -> SourceUnpackedness -> u # gmapM :: Monad m => (forall d. Data d => d -> m d) -> SourceUnpackedness -> m SourceUnpackedness # gmapMp :: MonadPlus m => (forall d. Data d => d -> m d) -> SourceUnpackedness -> m SourceUnpackedness # gmapMo :: MonadPlus m => (forall d. Data d => d -> m d) -> SourceUnpackedness -> m SourceUnpackedness # | |
Data SourceStrictness | Since: base-4.9.0.0 |
Defined in Data.Data gfoldl :: (forall d b. Data d => c (d -> b) -> d -> c b) -> (forall g. g -> c g) -> SourceStrictness -> c SourceStrictness # gunfold :: (forall b r. Data b => c (b -> r) -> c r) -> (forall r. r -> c r) -> Constr -> c SourceStrictness # toConstr :: SourceStrictness -> Constr # dataTypeOf :: SourceStrictness -> DataType # dataCast1 :: Typeable t => (forall d. Data d => c (t d)) -> Maybe (c SourceStrictness) # dataCast2 :: Typeable t => (forall d e. (Data d, Data e) => c (t d e)) -> Maybe (c SourceStrictness) # gmapT :: (forall b. Data b => b -> b) -> SourceStrictness -> SourceStrictness # gmapQl :: (r -> r' -> r) -> r -> (forall d. Data d => d -> r') -> SourceStrictness -> r # gmapQr :: (r' -> r -> r) -> r -> (forall d. Data d => d -> r') -> SourceStrictness -> r # gmapQ :: (forall d. Data d => d -> u) -> SourceStrictness -> [u] # gmapQi :: Int -> (forall d. Data d => d -> u) -> SourceStrictness -> u # gmapM :: Monad m => (forall d. Data d => d -> m d) -> SourceStrictness -> m SourceStrictness # gmapMp :: MonadPlus m => (forall d. Data d => d -> m d) -> SourceStrictness -> m SourceStrictness # gmapMo :: MonadPlus m => (forall d. Data d => d -> m d) -> SourceStrictness -> m SourceStrictness # | |
Data DecidedStrictness | Since: base-4.9.0.0 |
Defined in Data.Data gfoldl :: (forall d b. Data d => c (d -> b) -> d -> c b) -> (forall g. g -> c g) -> DecidedStrictness -> c DecidedStrictness # gunfold :: (forall b r. Data b => c (b -> r) -> c r) -> (forall r. r -> c r) -> Constr -> c DecidedStrictness # toConstr :: DecidedStrictness -> Constr # dataTypeOf :: DecidedStrictness -> DataType # dataCast1 :: Typeable t => (forall d. Data d => c (t d)) -> Maybe (c DecidedStrictness) # dataCast2 :: Typeable t => (forall d e. (Data d, Data e) => c (t d e)) -> Maybe (c DecidedStrictness) # gmapT :: (forall b. Data b => b -> b) -> DecidedStrictness -> DecidedStrictness # gmapQl :: (r -> r' -> r) -> r -> (forall d. Data d => d -> r') -> DecidedStrictness -> r # gmapQr :: (r' -> r -> r) -> r -> (forall d. Data d => d -> r') -> DecidedStrictness -> r # gmapQ :: (forall d. Data d => d -> u) -> DecidedStrictness -> [u] # gmapQi :: Int -> (forall d. Data d => d -> u) -> DecidedStrictness -> u # gmapM :: Monad m => (forall d. Data d => d -> m d) -> DecidedStrictness -> m DecidedStrictness # gmapMp :: MonadPlus m => (forall d. Data d => d -> m d) -> DecidedStrictness -> m DecidedStrictness # gmapMo :: MonadPlus m => (forall d. Data d => d -> m d) -> DecidedStrictness -> m DecidedStrictness # | |
Data WordPtr | Since: base-4.11.0.0 |
Defined in Data.Data gfoldl :: (forall d b. Data d => c (d -> b) -> d -> c b) -> (forall g. g -> c g) -> WordPtr -> c WordPtr # gunfold :: (forall b r. Data b => c (b -> r) -> c r) -> (forall r. r -> c r) -> Constr -> c WordPtr # toConstr :: WordPtr -> Constr # dataTypeOf :: WordPtr -> DataType # dataCast1 :: Typeable t => (forall d. Data d => c (t d)) -> Maybe (c WordPtr) # dataCast2 :: Typeable t => (forall d e. (Data d, Data e) => c (t d e)) -> Maybe (c WordPtr) # gmapT :: (forall b. Data b => b -> b) -> WordPtr -> WordPtr # gmapQl :: (r -> r' -> r) -> r -> (forall d. Data d => d -> r') -> WordPtr -> r # gmapQr :: (r' -> r -> r) -> r -> (forall d. Data d => d -> r') -> WordPtr -> r # gmapQ :: (forall d. Data d => d -> u) -> WordPtr -> [u] # gmapQi :: Int -> (forall d. Data d => d -> u) -> WordPtr -> u # gmapM :: Monad m => (forall d. Data d => d -> m d) -> WordPtr -> m WordPtr # gmapMp :: MonadPlus m => (forall d. Data d => d -> m d) -> WordPtr -> m WordPtr # gmapMo :: MonadPlus m => (forall d. Data d => d -> m d) -> WordPtr -> m WordPtr # | |
Data IntPtr | Since: base-4.11.0.0 |
Defined in Data.Data gfoldl :: (forall d b. Data d => c (d -> b) -> d -> c b) -> (forall g. g -> c g) -> IntPtr -> c IntPtr # gunfold :: (forall b r. Data b => c (b -> r) -> c r) -> (forall r. r -> c r) -> Constr -> c IntPtr # toConstr :: IntPtr -> Constr # dataTypeOf :: IntPtr -> DataType # dataCast1 :: Typeable t => (forall d. Data d => c (t d)) -> Maybe (c IntPtr) # dataCast2 :: Typeable t => (forall d e. (Data d, Data e) => c (t d e)) -> Maybe (c IntPtr) # gmapT :: (forall b. Data b => b -> b) -> IntPtr -> IntPtr # gmapQl :: (r -> r' -> r) -> r -> (forall d. Data d => d -> r') -> IntPtr -> r # gmapQr :: (r' -> r -> r) -> r -> (forall d. Data d => d -> r') -> IntPtr -> r # gmapQ :: (forall d. Data d => d -> u) -> IntPtr -> [u] # gmapQi :: Int -> (forall d. Data d => d -> u) -> IntPtr -> u # gmapM :: Monad m => (forall d. Data d => d -> m d) -> IntPtr -> m IntPtr # gmapMp :: MonadPlus m => (forall d. Data d => d -> m d) -> IntPtr -> m IntPtr # gmapMo :: MonadPlus m => (forall d. Data d => d -> m d) -> IntPtr -> m IntPtr # | |
Data a => Data [a] | Since: base-4.0.0.0 |
Defined in Data.Data gfoldl :: (forall d b. Data d => c (d -> b) -> d -> c b) -> (forall g. g -> c g) -> [a] -> c [a] # gunfold :: (forall b r. Data b => c (b -> r) -> c r) -> (forall r. r -> c r) -> Constr -> c [a] # dataTypeOf :: [a] -> DataType # dataCast1 :: Typeable t => (forall d. Data d => c (t d)) -> Maybe (c [a]) # dataCast2 :: Typeable t => (forall d e. (Data d, Data e) => c (t d e)) -> Maybe (c [a]) # gmapT :: (forall b. Data b => b -> b) -> [a] -> [a] # gmapQl :: (r -> r' -> r) -> r -> (forall d. Data d => d -> r') -> [a] -> r # gmapQr :: (r' -> r -> r) -> r -> (forall d. Data d => d -> r') -> [a] -> r # gmapQ :: (forall d. Data d => d -> u) -> [a] -> [u] # gmapQi :: Int -> (forall d. Data d => d -> u) -> [a] -> u # gmapM :: Monad m => (forall d. Data d => d -> m d) -> [a] -> m [a] # gmapMp :: MonadPlus m => (forall d. Data d => d -> m d) -> [a] -> m [a] # gmapMo :: MonadPlus m => (forall d. Data d => d -> m d) -> [a] -> m [a] # | |
Data a => Data (Maybe a) | Since: base-4.0.0.0 |
Defined in Data.Data gfoldl :: (forall d b. Data d => c (d -> b) -> d -> c b) -> (forall g. g -> c g) -> Maybe a -> c (Maybe a) # gunfold :: (forall b r. Data b => c (b -> r) -> c r) -> (forall r. r -> c r) -> Constr -> c (Maybe a) # toConstr :: Maybe a -> Constr # dataTypeOf :: Maybe a -> DataType # dataCast1 :: Typeable t => (forall d. Data d => c (t d)) -> Maybe (c (Maybe a)) # dataCast2 :: Typeable t => (forall d e. (Data d, Data e) => c (t d e)) -> Maybe (c (Maybe a)) # gmapT :: (forall b. Data b => b -> b) -> Maybe a -> Maybe a # gmapQl :: (r -> r' -> r) -> r -> (forall d. Data d => d -> r') -> Maybe a -> r # gmapQr :: (r' -> r -> r) -> r -> (forall d. Data d => d -> r') -> Maybe a -> r # gmapQ :: (forall d. Data d => d -> u) -> Maybe a -> [u] # gmapQi :: Int -> (forall d. Data d => d -> u) -> Maybe a -> u # gmapM :: Monad m => (forall d. Data d => d -> m d) -> Maybe a -> m (Maybe a) # gmapMp :: MonadPlus m => (forall d. Data d => d -> m d) -> Maybe a -> m (Maybe a) # gmapMo :: MonadPlus m => (forall d. Data d => d -> m d) -> Maybe a -> m (Maybe a) # | |
(Data a, Integral a) => Data (Ratio a) | Since: base-4.0.0.0 |
Defined in Data.Data gfoldl :: (forall d b. Data d => c (d -> b) -> d -> c b) -> (forall g. g -> c g) -> Ratio a -> c (Ratio a) # gunfold :: (forall b r. Data b => c (b -> r) -> c r) -> (forall r. r -> c r) -> Constr -> c (Ratio a) # toConstr :: Ratio a -> Constr # dataTypeOf :: Ratio a -> DataType # dataCast1 :: Typeable t => (forall d. Data d => c (t d)) -> Maybe (c (Ratio a)) # dataCast2 :: Typeable t => (forall d e. (Data d, Data e) => c (t d e)) -> Maybe (c (Ratio a)) # gmapT :: (forall b. Data b => b -> b) -> Ratio a -> Ratio a # gmapQl :: (r -> r' -> r) -> r -> (forall d. Data d => d -> r') -> Ratio a -> r # gmapQr :: (r' -> r -> r) -> r -> (forall d. Data d => d -> r') -> Ratio a -> r # gmapQ :: (forall d. Data d => d -> u) -> Ratio a -> [u] # gmapQi :: Int -> (forall d. Data d => d -> u) -> Ratio a -> u # gmapM :: Monad m => (forall d. Data d => d -> m d) -> Ratio a -> m (Ratio a) # gmapMp :: MonadPlus m => (forall d. Data d => d -> m d) -> Ratio a -> m (Ratio a) # gmapMo :: MonadPlus m => (forall d. Data d => d -> m d) -> Ratio a -> m (Ratio a) # | |
Data a => Data (Ptr a) | Since: base-4.8.0.0 |
Defined in Data.Data gfoldl :: (forall d b. Data d => c (d -> b) -> d -> c b) -> (forall g. g -> c g) -> Ptr a -> c (Ptr a) # gunfold :: (forall b r. Data b => c (b -> r) -> c r) -> (forall r. r -> c r) -> Constr -> c (Ptr a) # dataTypeOf :: Ptr a -> DataType # dataCast1 :: Typeable t => (forall d. Data d => c (t d)) -> Maybe (c (Ptr a)) # dataCast2 :: Typeable t => (forall d e. (Data d, Data e) => c (t d e)) -> Maybe (c (Ptr a)) # gmapT :: (forall b. Data b => b -> b) -> Ptr a -> Ptr a # gmapQl :: (r -> r' -> r) -> r -> (forall d. Data d => d -> r') -> Ptr a -> r # gmapQr :: (r' -> r -> r) -> r -> (forall d. Data d => d -> r') -> Ptr a -> r # gmapQ :: (forall d. Data d => d -> u) -> Ptr a -> [u] # gmapQi :: Int -> (forall d. Data d => d -> u) -> Ptr a -> u # gmapM :: Monad m => (forall d. Data d => d -> m d) -> Ptr a -> m (Ptr a) # gmapMp :: MonadPlus m => (forall d. Data d => d -> m d) -> Ptr a -> m (Ptr a) # gmapMo :: MonadPlus m => (forall d. Data d => d -> m d) -> Ptr a -> m (Ptr a) # | |
Data p => Data (Par1 p) | Since: base-4.9.0.0 |
Defined in Data.Data gfoldl :: (forall d b. Data d => c (d -> b) -> d -> c b) -> (forall g. g -> c g) -> Par1 p -> c (Par1 p) # gunfold :: (forall b r. Data b => c (b -> r) -> c r) -> (forall r. r -> c r) -> Constr -> c (Par1 p) # toConstr :: Par1 p -> Constr # dataTypeOf :: Par1 p -> DataType # dataCast1 :: Typeable t => (forall d. Data d => c (t d)) -> Maybe (c (Par1 p)) # dataCast2 :: Typeable t => (forall d e. (Data d, Data e) => c (t d e)) -> Maybe (c (Par1 p)) # gmapT :: (forall b. Data b => b -> b) -> Par1 p -> Par1 p # gmapQl :: (r -> r' -> r) -> r -> (forall d. Data d => d -> r') -> Par1 p -> r # gmapQr :: (r' -> r -> r) -> r -> (forall d. Data d => d -> r') -> Par1 p -> r # gmapQ :: (forall d. Data d => d -> u) -> Par1 p -> [u] # gmapQi :: Int -> (forall d. Data d => d -> u) -> Par1 p -> u # gmapM :: Monad m => (forall d. Data d => d -> m d) -> Par1 p -> m (Par1 p) # gmapMp :: MonadPlus m => (forall d. Data d => d -> m d) -> Par1 p -> m (Par1 p) # gmapMo :: MonadPlus m => (forall d. Data d => d -> m d) -> Par1 p -> m (Par1 p) # | |
Data a => Data (Min a) | |
Defined in Data.Semigroup gfoldl :: (forall d b. Data d => c (d -> b) -> d -> c b) -> (forall g. g -> c g) -> Min a -> c (Min a) # gunfold :: (forall b r. Data b => c (b -> r) -> c r) -> (forall r. r -> c r) -> Constr -> c (Min a) # dataTypeOf :: Min a -> DataType # dataCast1 :: Typeable t => (forall d. Data d => c (t d)) -> Maybe (c (Min a)) # dataCast2 :: Typeable t => (forall d e. (Data d, Data e) => c (t d e)) -> Maybe (c (Min a)) # gmapT :: (forall b. Data b => b -> b) -> Min a -> Min a # gmapQl :: (r -> r' -> r) -> r -> (forall d. Data d => d -> r') -> Min a -> r # gmapQr :: (r' -> r -> r) -> r -> (forall d. Data d => d -> r') -> Min a -> r # gmapQ :: (forall d. Data d => d -> u) -> Min a -> [u] # gmapQi :: Int -> (forall d. Data d => d -> u) -> Min a -> u # gmapM :: Monad m => (forall d. Data d => d -> m d) -> Min a -> m (Min a) # gmapMp :: MonadPlus m => (forall d. Data d => d -> m d) -> Min a -> m (Min a) # gmapMo :: MonadPlus m => (forall d. Data d => d -> m d) -> Min a -> m (Min a) # | |
Data a => Data (Max a) | |
Defined in Data.Semigroup gfoldl :: (forall d b. Data d => c (d -> b) -> d -> c b) -> (forall g. g -> c g) -> Max a -> c (Max a) # gunfold :: (forall b r. Data b => c (b -> r) -> c r) -> (forall r. r -> c r) -> Constr -> c (Max a) # dataTypeOf :: Max a -> DataType # dataCast1 :: Typeable t => (forall d. Data d => c (t d)) -> Maybe (c (Max a)) # dataCast2 :: Typeable t => (forall d e. (Data d, Data e) => c (t d e)) -> Maybe (c (Max a)) # gmapT :: (forall b. Data b => b -> b) -> Max a -> Max a # gmapQl :: (r -> r' -> r) -> r -> (forall d. Data d => d -> r') -> Max a -> r # gmapQr :: (r' -> r -> r) -> r -> (forall d. Data d => d -> r') -> Max a -> r # gmapQ :: (forall d. Data d => d -> u) -> Max a -> [u] # gmapQi :: Int -> (forall d. Data d => d -> u) -> Max a -> u # gmapM :: Monad m => (forall d. Data d => d -> m d) -> Max a -> m (Max a) # gmapMp :: MonadPlus m => (forall d. Data d => d -> m d) -> Max a -> m (Max a) # gmapMo :: MonadPlus m => (forall d. Data d => d -> m d) -> Max a -> m (Max a) # | |
Data a => Data (First a) | |
Defined in Data.Semigroup gfoldl :: (forall d b. Data d => c (d -> b) -> d -> c b) -> (forall g. g -> c g) -> First a -> c (First a) # gunfold :: (forall b r. Data b => c (b -> r) -> c r) -> (forall r. r -> c r) -> Constr -> c (First a) # toConstr :: First a -> Constr # dataTypeOf :: First a -> DataType # dataCast1 :: Typeable t => (forall d. Data d => c (t d)) -> Maybe (c (First a)) # dataCast2 :: Typeable t => (forall d e. (Data d, Data e) => c (t d e)) -> Maybe (c (First a)) # gmapT :: (forall b. Data b => b -> b) -> First a -> First a # gmapQl :: (r -> r' -> r) -> r -> (forall d. Data d => d -> r') -> First a -> r # gmapQr :: (r' -> r -> r) -> r -> (forall d. Data d => d -> r') -> First a -> r # gmapQ :: (forall d. Data d => d -> u) -> First a -> [u] # gmapQi :: Int -> (forall d. Data d => d -> u) -> First a -> u # gmapM :: Monad m => (forall d. Data d => d -> m d) -> First a -> m (First a) # gmapMp :: MonadPlus m => (forall d. Data d => d -> m d) -> First a -> m (First a) # gmapMo :: MonadPlus m => (forall d. Data d => d -> m d) -> First a -> m (First a) # | |
Data a => Data (Last a) | |
Defined in Data.Semigroup gfoldl :: (forall d b. Data d => c (d -> b) -> d -> c b) -> (forall g. g -> c g) -> Last a -> c (Last a) # gunfold :: (forall b r. Data b => c (b -> r) -> c r) -> (forall r. r -> c r) -> Constr -> c (Last a) # toConstr :: Last a -> Constr # dataTypeOf :: Last a -> DataType # dataCast1 :: Typeable t => (forall d. Data d => c (t d)) -> Maybe (c (Last a)) # dataCast2 :: Typeable t => (forall d e. (Data d, Data e) => c (t d e)) -> Maybe (c (Last a)) # gmapT :: (forall b. Data b => b -> b) -> Last a -> Last a # gmapQl :: (r -> r' -> r) -> r -> (forall d. Data d => d -> r') -> Last a -> r # gmapQr :: (r' -> r -> r) -> r -> (forall d. Data d => d -> r') -> Last a -> r # gmapQ :: (forall d. Data d => d -> u) -> Last a -> [u] # gmapQi :: Int -> (forall d. Data d => d -> u) -> Last a -> u # gmapM :: Monad m => (forall d. Data d => d -> m d) -> Last a -> m (Last a) # gmapMp :: MonadPlus m => (forall d. Data d => d -> m d) -> Last a -> m (Last a) # gmapMo :: MonadPlus m => (forall d. Data d => d -> m d) -> Last a -> m (Last a) # | |
Data m => Data (WrappedMonoid m) | |
Defined in Data.Semigroup gfoldl :: (forall d b. Data d => c (d -> b) -> d -> c b) -> (forall g. g -> c g) -> WrappedMonoid m -> c (WrappedMonoid m) # gunfold :: (forall b r. Data b => c (b -> r) -> c r) -> (forall r. r -> c r) -> Constr -> c (WrappedMonoid m) # toConstr :: WrappedMonoid m -> Constr # dataTypeOf :: WrappedMonoid m -> DataType # dataCast1 :: Typeable t => (forall d. Data d => c (t d)) -> Maybe (c (WrappedMonoid m)) # dataCast2 :: Typeable t => (forall d e. (Data d, Data e) => c (t d e)) -> Maybe (c (WrappedMonoid m)) # gmapT :: (forall b. Data b => b -> b) -> WrappedMonoid m -> WrappedMonoid m # gmapQl :: (r -> r' -> r) -> r -> (forall d. Data d => d -> r') -> WrappedMonoid m -> r # gmapQr :: (r' -> r -> r) -> r -> (forall d. Data d => d -> r') -> WrappedMonoid m -> r # gmapQ :: (forall d. Data d => d -> u) -> WrappedMonoid m -> [u] # gmapQi :: Int -> (forall d. Data d => d -> u) -> WrappedMonoid m -> u # gmapM :: Monad m0 => (forall d. Data d => d -> m0 d) -> WrappedMonoid m -> m0 (WrappedMonoid m) # gmapMp :: MonadPlus m0 => (forall d. Data d => d -> m0 d) -> WrappedMonoid m -> m0 (WrappedMonoid m) # gmapMo :: MonadPlus m0 => (forall d. Data d => d -> m0 d) -> WrappedMonoid m -> m0 (WrappedMonoid m) # | |
Data a => Data (Option a) | |
Defined in Data.Semigroup gfoldl :: (forall d b. Data d => c (d -> b) -> d -> c b) -> (forall g. g -> c g) -> Option a -> c (Option a) # gunfold :: (forall b r. Data b => c (b -> r) -> c r) -> (forall r. r -> c r) -> Constr -> c (Option a) # toConstr :: Option a -> Constr # dataTypeOf :: Option a -> DataType # dataCast1 :: Typeable t => (forall d. Data d => c (t d)) -> Maybe (c (Option a)) # dataCast2 :: Typeable t => (forall d e. (Data d, Data e) => c (t d e)) -> Maybe (c (Option a)) # gmapT :: (forall b. Data b => b -> b) -> Option a -> Option a # gmapQl :: (r -> r' -> r) -> r -> (forall d. Data d => d -> r') -> Option a -> r # gmapQr :: (r' -> r -> r) -> r -> (forall d. Data d => d -> r') -> Option a -> r # gmapQ :: (forall d. Data d => d -> u) -> Option a -> [u] # gmapQi :: Int -> (forall d. Data d => d -> u) -> Option a -> u # gmapM :: Monad m => (forall d. Data d => d -> m d) -> Option a -> m (Option a) # gmapMp :: MonadPlus m => (forall d. Data d => d -> m d) -> Option a -> m (Option a) # gmapMo :: MonadPlus m => (forall d. Data d => d -> m d) -> Option a -> m (Option a) # | |
Data a => Data (Identity a) | Since: base-4.9.0.0 |
Defined in Data.Data gfoldl :: (forall d b. Data d => c (d -> b) -> d -> c b) -> (forall g. g -> c g) -> Identity a -> c (Identity a) # gunfold :: (forall b r. Data b => c (b -> r) -> c r) -> (forall r. r -> c r) -> Constr -> c (Identity a) # toConstr :: Identity a -> Constr # dataTypeOf :: Identity a -> DataType # dataCast1 :: Typeable t => (forall d. Data d => c (t d)) -> Maybe (c (Identity a)) # dataCast2 :: Typeable t => (forall d e. (Data d, Data e) => c (t d e)) -> Maybe (c (Identity a)) # gmapT :: (forall b. Data b => b -> b) -> Identity a -> Identity a # gmapQl :: (r -> r' -> r) -> r -> (forall d. Data d => d -> r') -> Identity a -> r # gmapQr :: (r' -> r -> r) -> r -> (forall d. Data d => d -> r') -> Identity a -> r # gmapQ :: (forall d. Data d => d -> u) -> Identity a -> [u] # gmapQi :: Int -> (forall d. Data d => d -> u) -> Identity a -> u # gmapM :: Monad m => (forall d. Data d => d -> m d) -> Identity a -> m (Identity a) # gmapMp :: MonadPlus m => (forall d. Data d => d -> m d) -> Identity a -> m (Identity a) # gmapMo :: MonadPlus m => (forall d. Data d => d -> m d) -> Identity a -> m (Identity a) # | |
Data a => Data (ForeignPtr a) | Since: base-4.8.0.0 |
Defined in Data.Data gfoldl :: (forall d b. Data d => c (d -> b) -> d -> c b) -> (forall g. g -> c g) -> ForeignPtr a -> c (ForeignPtr a) # gunfold :: (forall b r. Data b => c (b -> r) -> c r) -> (forall r. r -> c r) -> Constr -> c (ForeignPtr a) # toConstr :: ForeignPtr a -> Constr # dataTypeOf :: ForeignPtr a -> DataType # dataCast1 :: Typeable t => (forall d. Data d => c (t d)) -> Maybe (c (ForeignPtr a)) # dataCast2 :: Typeable t => (forall d e. (Data d, Data e) => c (t d e)) -> Maybe (c (ForeignPtr a)) # gmapT :: (forall b. Data b => b -> b) -> ForeignPtr a -> ForeignPtr a # gmapQl :: (r -> r' -> r) -> r -> (forall d. Data d => d -> r') -> ForeignPtr a -> r # gmapQr :: (r' -> r -> r) -> r -> (forall d. Data d => d -> r') -> ForeignPtr a -> r # gmapQ :: (forall d. Data d => d -> u) -> ForeignPtr a -> [u] # gmapQi :: Int -> (forall d. Data d => d -> u) -> ForeignPtr a -> u # gmapM :: Monad m => (forall d. Data d => d -> m d) -> ForeignPtr a -> m (ForeignPtr a) # gmapMp :: MonadPlus m => (forall d. Data d => d -> m d) -> ForeignPtr a -> m (ForeignPtr a) # gmapMo :: MonadPlus m => (forall d. Data d => d -> m d) -> ForeignPtr a -> m (ForeignPtr a) # | |
Data a => Data (First a) | Since: base-4.8.0.0 |
Defined in Data.Data gfoldl :: (forall d b. Data d => c (d -> b) -> d -> c b) -> (forall g. g -> c g) -> First a -> c (First a) # gunfold :: (forall b r. Data b => c (b -> r) -> c r) -> (forall r. r -> c r) -> Constr -> c (First a) # toConstr :: First a -> Constr # dataTypeOf :: First a -> DataType # dataCast1 :: Typeable t => (forall d. Data d => c (t d)) -> Maybe (c (First a)) # dataCast2 :: Typeable t => (forall d e. (Data d, Data e) => c (t d e)) -> Maybe (c (First a)) # gmapT :: (forall b. Data b => b -> b) -> First a -> First a # gmapQl :: (r -> r' -> r) -> r -> (forall d. Data d => d -> r') -> First a -> r # gmapQr :: (r' -> r -> r) -> r -> (forall d. Data d => d -> r') -> First a -> r # gmapQ :: (forall d. Data d => d -> u) -> First a -> [u] # gmapQi :: Int -> (forall d. Data d => d -> u) -> First a -> u # gmapM :: Monad m => (forall d. Data d => d -> m d) -> First a -> m (First a) # gmapMp :: MonadPlus m => (forall d. Data d => d -> m d) -> First a -> m (First a) # gmapMo :: MonadPlus m => (forall d. Data d => d -> m d) -> First a -> m (First a) # | |
Data a => Data (Last a) | Since: base-4.8.0.0 |
Defined in Data.Data gfoldl :: (forall d b. Data d => c (d -> b) -> d -> c b) -> (forall g. g -> c g) -> Last a -> c (Last a) # gunfold :: (forall b r. Data b => c (b -> r) -> c r) -> (forall r. r -> c r) -> Constr -> c (Last a) # toConstr :: Last a -> Constr # dataTypeOf :: Last a -> DataType # dataCast1 :: Typeable t => (forall d. Data d => c (t d)) -> Maybe (c (Last a)) # dataCast2 :: Typeable t => (forall d e. (Data d, Data e) => c (t d e)) -> Maybe (c (Last a)) # gmapT :: (forall b. Data b => b -> b) -> Last a -> Last a # gmapQl :: (r -> r' -> r) -> r -> (forall d. Data d => d -> r') -> Last a -> r # gmapQr :: (r' -> r -> r) -> r -> (forall d. Data d => d -> r') -> Last a -> r # gmapQ :: (forall d. Data d => d -> u) -> Last a -> [u] # gmapQi :: Int -> (forall d. Data d => d -> u) -> Last a -> u # gmapM :: Monad m => (forall d. Data d => d -> m d) -> Last a -> m (Last a) # gmapMp :: MonadPlus m => (forall d. Data d => d -> m d) -> Last a -> m (Last a) # gmapMo :: MonadPlus m => (forall d. Data d => d -> m d) -> Last a -> m (Last a) # | |
Data a => Data (Dual a) | Since: base-4.8.0.0 |
Defined in Data.Data gfoldl :: (forall d b. Data d => c (d -> b) -> d -> c b) -> (forall g. g -> c g) -> Dual a -> c (Dual a) # gunfold :: (forall b r. Data b => c (b -> r) -> c r) -> (forall r. r -> c r) -> Constr -> c (Dual a) # toConstr :: Dual a -> Constr # dataTypeOf :: Dual a -> DataType # dataCast1 :: Typeable t => (forall d. Data d => c (t d)) -> Maybe (c (Dual a)) # dataCast2 :: Typeable t => (forall d e. (Data d, Data e) => c (t d e)) -> Maybe (c (Dual a)) # gmapT :: (forall b. Data b => b -> b) -> Dual a -> Dual a # gmapQl :: (r -> r' -> r) -> r -> (forall d. Data d => d -> r') -> Dual a -> r # gmapQr :: (r' -> r -> r) -> r -> (forall d. Data d => d -> r') -> Dual a -> r # gmapQ :: (forall d. Data d => d -> u) -> Dual a -> [u] # gmapQi :: Int -> (forall d. Data d => d -> u) -> Dual a -> u # gmapM :: Monad m => (forall d. Data d => d -> m d) -> Dual a -> m (Dual a) # gmapMp :: MonadPlus m => (forall d. Data d => d -> m d) -> Dual a -> m (Dual a) # gmapMo :: MonadPlus m => (forall d. Data d => d -> m d) -> Dual a -> m (Dual a) # | |
Data a => Data (Sum a) | Since: base-4.8.0.0 |
Defined in Data.Data gfoldl :: (forall d b. Data d => c (d -> b) -> d -> c b) -> (forall g. g -> c g) -> Sum a -> c (Sum a) # gunfold :: (forall b r. Data b => c (b -> r) -> c r) -> (forall r. r -> c r) -> Constr -> c (Sum a) # dataTypeOf :: Sum a -> DataType # dataCast1 :: Typeable t => (forall d. Data d => c (t d)) -> Maybe (c (Sum a)) # dataCast2 :: Typeable t => (forall d e. (Data d, Data e) => c (t d e)) -> Maybe (c (Sum a)) # gmapT :: (forall b. Data b => b -> b) -> Sum a -> Sum a # gmapQl :: (r -> r' -> r) -> r -> (forall d. Data d => d -> r') -> Sum a -> r # gmapQr :: (r' -> r -> r) -> r -> (forall d. Data d => d -> r') -> Sum a -> r # gmapQ :: (forall d. Data d => d -> u) -> Sum a -> [u] # gmapQi :: Int -> (forall d. Data d => d -> u) -> Sum a -> u # gmapM :: Monad m => (forall d. Data d => d -> m d) -> Sum a -> m (Sum a) # gmapMp :: MonadPlus m => (forall d. Data d => d -> m d) -> Sum a -> m (Sum a) # gmapMo :: MonadPlus m => (forall d. Data d => d -> m d) -> Sum a -> m (Sum a) # | |
Data a => Data (Product a) | Since: base-4.8.0.0 |
Defined in Data.Data gfoldl :: (forall d b. Data d => c (d -> b) -> d -> c b) -> (forall g. g -> c g) -> Product a -> c (Product a) # gunfold :: (forall b r. Data b => c (b -> r) -> c r) -> (forall r. r -> c r) -> Constr -> c (Product a) # toConstr :: Product a -> Constr # dataTypeOf :: Product a -> DataType # dataCast1 :: Typeable t => (forall d. Data d => c (t d)) -> Maybe (c (Product a)) # dataCast2 :: Typeable t => (forall d e. (Data d, Data e) => c (t d e)) -> Maybe (c (Product a)) # gmapT :: (forall b. Data b => b -> b) -> Product a -> Product a # gmapQl :: (r -> r' -> r) -> r -> (forall d. Data d => d -> r') -> Product a -> r # gmapQr :: (r' -> r -> r) -> r -> (forall d. Data d => d -> r') -> Product a -> r # gmapQ :: (forall d. Data d => d -> u) -> Product a -> [u] # gmapQi :: Int -> (forall d. Data d => d -> u) -> Product a -> u # gmapM :: Monad m => (forall d. Data d => d -> m d) -> Product a -> m (Product a) # gmapMp :: MonadPlus m => (forall d. Data d => d -> m d) -> Product a -> m (Product a) # gmapMo :: MonadPlus m => (forall d. Data d => d -> m d) -> Product a -> m (Product a) # | |
Data a => Data (NonEmpty a) | Since: base-4.9.0.0 |
Defined in Data.Data gfoldl :: (forall d b. Data d => c (d -> b) -> d -> c b) -> (forall g. g -> c g) -> NonEmpty a -> c (NonEmpty a) # gunfold :: (forall b r. Data b => c (b -> r) -> c r) -> (forall r. r -> c r) -> Constr -> c (NonEmpty a) # toConstr :: NonEmpty a -> Constr # dataTypeOf :: NonEmpty a -> DataType # dataCast1 :: Typeable t => (forall d. Data d => c (t d)) -> Maybe (c (NonEmpty a)) # dataCast2 :: Typeable t => (forall d e. (Data d, Data e) => c (t d e)) -> Maybe (c (NonEmpty a)) # gmapT :: (forall b. Data b => b -> b) -> NonEmpty a -> NonEmpty a # gmapQl :: (r -> r' -> r) -> r -> (forall d. Data d => d -> r') -> NonEmpty a -> r # gmapQr :: (r' -> r -> r) -> r -> (forall d. Data d => d -> r') -> NonEmpty a -> r # gmapQ :: (forall d. Data d => d -> u) -> NonEmpty a -> [u] # gmapQi :: Int -> (forall d. Data d => d -> u) -> NonEmpty a -> u # gmapM :: Monad m => (forall d. Data d => d -> m d) -> NonEmpty a -> m (NonEmpty a) # gmapMp :: MonadPlus m => (forall d. Data d => d -> m d) -> NonEmpty a -> m (NonEmpty a) # gmapMo :: MonadPlus m => (forall d. Data d => d -> m d) -> NonEmpty a -> m (NonEmpty a) # | |
(Data a, Data b) => Data (Either a b) | Since: base-4.0.0.0 |
Defined in Data.Data gfoldl :: (forall d b0. Data d => c (d -> b0) -> d -> c b0) -> (forall g. g -> c g) -> Either a b -> c (Either a b) # gunfold :: (forall b0 r. Data b0 => c (b0 -> r) -> c r) -> (forall r. r -> c r) -> Constr -> c (Either a b) # toConstr :: Either a b -> Constr # dataTypeOf :: Either a b -> DataType # dataCast1 :: Typeable t => (forall d. Data d => c (t d)) -> Maybe (c (Either a b)) # dataCast2 :: Typeable t => (forall d e. (Data d, Data e) => c (t d e)) -> Maybe (c (Either a b)) # gmapT :: (forall b0. Data b0 => b0 -> b0) -> Either a b -> Either a b # gmapQl :: (r -> r' -> r) -> r -> (forall d. Data d => d -> r') -> Either a b -> r # gmapQr :: (r' -> r -> r) -> r -> (forall d. Data d => d -> r') -> Either a b -> r # gmapQ :: (forall d. Data d => d -> u) -> Either a b -> [u] # gmapQi :: Int -> (forall d. Data d => d -> u) -> Either a b -> u # gmapM :: Monad m => (forall d. Data d => d -> m d) -> Either a b -> m (Either a b) # gmapMp :: MonadPlus m => (forall d. Data d => d -> m d) -> Either a b -> m (Either a b) # gmapMo :: MonadPlus m => (forall d. Data d => d -> m d) -> Either a b -> m (Either a b) # | |
Data p => Data (V1 p) | Since: base-4.9.0.0 |
Defined in Data.Data gfoldl :: (forall d b. Data d => c (d -> b) -> d -> c b) -> (forall g. g -> c g) -> V1 p -> c (V1 p) # gunfold :: (forall b r. Data b => c (b -> r) -> c r) -> (forall r. r -> c r) -> Constr -> c (V1 p) # dataTypeOf :: V1 p -> DataType # dataCast1 :: Typeable t => (forall d. Data d => c (t d)) -> Maybe (c (V1 p)) # dataCast2 :: Typeable t => (forall d e. (Data d, Data e) => c (t d e)) -> Maybe (c (V1 p)) # gmapT :: (forall b. Data b => b -> b) -> V1 p -> V1 p # gmapQl :: (r -> r' -> r) -> r -> (forall d. Data d => d -> r') -> V1 p -> r # gmapQr :: (r' -> r -> r) -> r -> (forall d. Data d => d -> r') -> V1 p -> r # gmapQ :: (forall d. Data d => d -> u) -> V1 p -> [u] # gmapQi :: Int -> (forall d. Data d => d -> u) -> V1 p -> u # gmapM :: Monad m => (forall d. Data d => d -> m d) -> V1 p -> m (V1 p) # gmapMp :: MonadPlus m => (forall d. Data d => d -> m d) -> V1 p -> m (V1 p) # gmapMo :: MonadPlus m => (forall d. Data d => d -> m d) -> V1 p -> m (V1 p) # | |
Data p => Data (U1 p) | Since: base-4.9.0.0 |
Defined in Data.Data gfoldl :: (forall d b. Data d => c (d -> b) -> d -> c b) -> (forall g. g -> c g) -> U1 p -> c (U1 p) # gunfold :: (forall b r. Data b => c (b -> r) -> c r) -> (forall r. r -> c r) -> Constr -> c (U1 p) # dataTypeOf :: U1 p -> DataType # dataCast1 :: Typeable t => (forall d. Data d => c (t d)) -> Maybe (c (U1 p)) # dataCast2 :: Typeable t => (forall d e. (Data d, Data e) => c (t d e)) -> Maybe (c (U1 p)) # gmapT :: (forall b. Data b => b -> b) -> U1 p -> U1 p # gmapQl :: (r -> r' -> r) -> r -> (forall d. Data d => d -> r') -> U1 p -> r # gmapQr :: (r' -> r -> r) -> r -> (forall d. Data d => d -> r') -> U1 p -> r # gmapQ :: (forall d. Data d => d -> u) -> U1 p -> [u] # gmapQi :: Int -> (forall d. Data d => d -> u) -> U1 p -> u # gmapM :: Monad m => (forall d. Data d => d -> m d) -> U1 p -> m (U1 p) # gmapMp :: MonadPlus m => (forall d. Data d => d -> m d) -> U1 p -> m (U1 p) # gmapMo :: MonadPlus m => (forall d. Data d => d -> m d) -> U1 p -> m (U1 p) # | |
(Data a, Data b) => Data (a, b) | Since: base-4.0.0.0 |
Defined in Data.Data gfoldl :: (forall d b0. Data d => c (d -> b0) -> d -> c b0) -> (forall g. g -> c g) -> (a, b) -> c (a, b) # gunfold :: (forall b0 r. Data b0 => c (b0 -> r) -> c r) -> (forall r. r -> c r) -> Constr -> c (a, b) # toConstr :: (a, b) -> Constr # dataTypeOf :: (a, b) -> DataType # dataCast1 :: Typeable t => (forall d. Data d => c (t d)) -> Maybe (c (a, b)) # dataCast2 :: Typeable t => (forall d e. (Data d, Data e) => c (t d e)) -> Maybe (c (a, b)) # gmapT :: (forall b0. Data b0 => b0 -> b0) -> (a, b) -> (a, b) # gmapQl :: (r -> r' -> r) -> r -> (forall d. Data d => d -> r') -> (a, b) -> r # gmapQr :: (r' -> r -> r) -> r -> (forall d. Data d => d -> r') -> (a, b) -> r # gmapQ :: (forall d. Data d => d -> u) -> (a, b) -> [u] # gmapQi :: Int -> (forall d. Data d => d -> u) -> (a, b) -> u # gmapM :: Monad m => (forall d. Data d => d -> m d) -> (a, b) -> m (a, b) # gmapMp :: MonadPlus m => (forall d. Data d => d -> m d) -> (a, b) -> m (a, b) # gmapMo :: MonadPlus m => (forall d. Data d => d -> m d) -> (a, b) -> m (a, b) # | |
(Data a, Data b, Ix a) => Data (Array a b) | Since: base-4.8.0.0 |
Defined in Data.Data gfoldl :: (forall d b0. Data d => c (d -> b0) -> d -> c b0) -> (forall g. g -> c g) -> Array a b -> c (Array a b) # gunfold :: (forall b0 r. Data b0 => c (b0 -> r) -> c r) -> (forall r. r -> c r) -> Constr -> c (Array a b) # toConstr :: Array a b -> Constr # dataTypeOf :: Array a b -> DataType # dataCast1 :: Typeable t => (forall d. Data d => c (t d)) -> Maybe (c (Array a b)) # dataCast2 :: Typeable t => (forall d e. (Data d, Data e) => c (t d e)) -> Maybe (c (Array a b)) # gmapT :: (forall b0. Data b0 => b0 -> b0) -> Array a b -> Array a b # gmapQl :: (r -> r' -> r) -> r -> (forall d. Data d => d -> r') -> Array a b -> r # gmapQr :: (r' -> r -> r) -> r -> (forall d. Data d => d -> r') -> Array a b -> r # gmapQ :: (forall d. Data d => d -> u) -> Array a b -> [u] # gmapQi :: Int -> (forall d. Data d => d -> u) -> Array a b -> u # gmapM :: Monad m => (forall d. Data d => d -> m d) -> Array a b -> m (Array a b) # gmapMp :: MonadPlus m => (forall d. Data d => d -> m d) -> Array a b -> m (Array a b) # gmapMo :: MonadPlus m => (forall d. Data d => d -> m d) -> Array a b -> m (Array a b) # | |
(Data a, Data b) => Data (Arg a b) | |
Defined in Data.Semigroup gfoldl :: (forall d b0. Data d => c (d -> b0) -> d -> c b0) -> (forall g. g -> c g) -> Arg a b -> c (Arg a b) # gunfold :: (forall b0 r. Data b0 => c (b0 -> r) -> c r) -> (forall r. r -> c r) -> Constr -> c (Arg a b) # toConstr :: Arg a b -> Constr # dataTypeOf :: Arg a b -> DataType # dataCast1 :: Typeable t => (forall d. Data d => c (t d)) -> Maybe (c (Arg a b)) # dataCast2 :: Typeable t => (forall d e. (Data d, Data e) => c (t d e)) -> Maybe (c (Arg a b)) # gmapT :: (forall b0. Data b0 => b0 -> b0) -> Arg a b -> Arg a b # gmapQl :: (r -> r' -> r) -> r -> (forall d. Data d => d -> r') -> Arg a b -> r # gmapQr :: (r' -> r -> r) -> r -> (forall d. Data d => d -> r') -> Arg a b -> r # gmapQ :: (forall d. Data d => d -> u) -> Arg a b -> [u] # gmapQi :: Int -> (forall d. Data d => d -> u) -> Arg a b -> u # gmapM :: Monad m => (forall d. Data d => d -> m d) -> Arg a b -> m (Arg a b) # gmapMp :: MonadPlus m => (forall d. Data d => d -> m d) -> Arg a b -> m (Arg a b) # gmapMo :: MonadPlus m => (forall d. Data d => d -> m d) -> Arg a b -> m (Arg a b) # | |
Data t => Data (Proxy t) | Since: base-4.7.0.0 |
Defined in Data.Data gfoldl :: (forall d b. Data d => c (d -> b) -> d -> c b) -> (forall g. g -> c g) -> Proxy t -> c (Proxy t) # gunfold :: (forall b r. Data b => c (b -> r) -> c r) -> (forall r. r -> c r) -> Constr -> c (Proxy t) # toConstr :: Proxy t -> Constr # dataTypeOf :: Proxy t -> DataType # dataCast1 :: Typeable t0 => (forall d. Data d => c (t0 d)) -> Maybe (c (Proxy t)) # dataCast2 :: Typeable t0 => (forall d e. (Data d, Data e) => c (t0 d e)) -> Maybe (c (Proxy t)) # gmapT :: (forall b. Data b => b -> b) -> Proxy t -> Proxy t # gmapQl :: (r -> r' -> r) -> r -> (forall d. Data d => d -> r') -> Proxy t -> r # gmapQr :: (r' -> r -> r) -> r -> (forall d. Data d => d -> r') -> Proxy t -> r # gmapQ :: (forall d. Data d => d -> u) -> Proxy t -> [u] # gmapQi :: Int -> (forall d. Data d => d -> u) -> Proxy t -> u # gmapM :: Monad m => (forall d. Data d => d -> m d) -> Proxy t -> m (Proxy t) # gmapMp :: MonadPlus m => (forall d. Data d => d -> m d) -> Proxy t -> m (Proxy t) # gmapMo :: MonadPlus m => (forall d. Data d => d -> m d) -> Proxy t -> m (Proxy t) # | |
(Data (f p), Typeable f, Data p) => Data (Rec1 f p) | Since: base-4.9.0.0 |
Defined in Data.Data gfoldl :: (forall d b. Data d => c (d -> b) -> d -> c b) -> (forall g. g -> c g) -> Rec1 f p -> c (Rec1 f p) # gunfold :: (forall b r. Data b => c (b -> r) -> c r) -> (forall r. r -> c r) -> Constr -> c (Rec1 f p) # toConstr :: Rec1 f p -> Constr # dataTypeOf :: Rec1 f p -> DataType # dataCast1 :: Typeable t => (forall d. Data d => c (t d)) -> Maybe (c (Rec1 f p)) # dataCast2 :: Typeable t => (forall d e. (Data d, Data e) => c (t d e)) -> Maybe (c (Rec1 f p)) # gmapT :: (forall b. Data b => b -> b) -> Rec1 f p -> Rec1 f p # gmapQl :: (r -> r' -> r) -> r -> (forall d. Data d => d -> r') -> Rec1 f p -> r # gmapQr :: (r' -> r -> r) -> r -> (forall d. Data d => d -> r') -> Rec1 f p -> r # gmapQ :: (forall d. Data d => d -> u) -> Rec1 f p -> [u] # gmapQi :: Int -> (forall d. Data d => d -> u) -> Rec1 f p -> u # gmapM :: Monad m => (forall d. Data d => d -> m d) -> Rec1 f p -> m (Rec1 f p) # gmapMp :: MonadPlus m => (forall d. Data d => d -> m d) -> Rec1 f p -> m (Rec1 f p) # gmapMo :: MonadPlus m => (forall d. Data d => d -> m d) -> Rec1 f p -> m (Rec1 f p) # | |
(Data a, Data b, Data c) => Data (a, b, c) | Since: base-4.0.0.0 |
Defined in Data.Data gfoldl :: (forall d b0. Data d => c0 (d -> b0) -> d -> c0 b0) -> (forall g. g -> c0 g) -> (a, b, c) -> c0 (a, b, c) # gunfold :: (forall b0 r. Data b0 => c0 (b0 -> r) -> c0 r) -> (forall r. r -> c0 r) -> Constr -> c0 (a, b, c) # toConstr :: (a, b, c) -> Constr # dataTypeOf :: (a, b, c) -> DataType # dataCast1 :: Typeable t => (forall d. Data d => c0 (t d)) -> Maybe (c0 (a, b, c)) # dataCast2 :: Typeable t => (forall d e. (Data d, Data e) => c0 (t d e)) -> Maybe (c0 (a, b, c)) # gmapT :: (forall b0. Data b0 => b0 -> b0) -> (a, b, c) -> (a, b, c) # gmapQl :: (r -> r' -> r) -> r -> (forall d. Data d => d -> r') -> (a, b, c) -> r # gmapQr :: (r' -> r -> r) -> r -> (forall d. Data d => d -> r') -> (a, b, c) -> r # gmapQ :: (forall d. Data d => d -> u) -> (a, b, c) -> [u] # gmapQi :: Int -> (forall d. Data d => d -> u) -> (a, b, c) -> u # gmapM :: Monad m => (forall d. Data d => d -> m d) -> (a, b, c) -> m (a, b, c) # gmapMp :: MonadPlus m => (forall d. Data d => d -> m d) -> (a, b, c) -> m (a, b, c) # gmapMo :: MonadPlus m => (forall d. Data d => d -> m d) -> (a, b, c) -> m (a, b, c) # | |
(Typeable k, Data a, Typeable b) => Data (Const a b) | Since: base-4.10.0.0 |
Defined in Data.Data gfoldl :: (forall d b0. Data d => c (d -> b0) -> d -> c b0) -> (forall g. g -> c g) -> Const a b -> c (Const a b) # gunfold :: (forall b0 r. Data b0 => c (b0 -> r) -> c r) -> (forall r. r -> c r) -> Constr -> c (Const a b) # toConstr :: Const a b -> Constr # dataTypeOf :: Const a b -> DataType # dataCast1 :: Typeable t => (forall d. Data d => c (t d)) -> Maybe (c (Const a b)) # dataCast2 :: Typeable t => (forall d e. (Data d, Data e) => c (t d e)) -> Maybe (c (Const a b)) # gmapT :: (forall b0. Data b0 => b0 -> b0) -> Const a b -> Const a b # gmapQl :: (r -> r' -> r) -> r -> (forall d. Data d => d -> r') -> Const a b -> r # gmapQr :: (r' -> r -> r) -> r -> (forall d. Data d => d -> r') -> Const a b -> r # gmapQ :: (forall d. Data d => d -> u) -> Const a b -> [u] # gmapQi :: Int -> (forall d. Data d => d -> u) -> Const a b -> u # gmapM :: Monad m => (forall d. Data d => d -> m d) -> Const a b -> m (Const a b) # gmapMp :: MonadPlus m => (forall d. Data d => d -> m d) -> Const a b -> m (Const a b) # gmapMo :: MonadPlus m => (forall d. Data d => d -> m d) -> Const a b -> m (Const a b) # | |
(Data (f a), Data a, Typeable f) => Data (Alt f a) | Since: base-4.8.0.0 |
Defined in Data.Data gfoldl :: (forall d b. Data d => c (d -> b) -> d -> c b) -> (forall g. g -> c g) -> Alt f a -> c (Alt f a) # gunfold :: (forall b r. Data b => c (b -> r) -> c r) -> (forall r. r -> c r) -> Constr -> c (Alt f a) # toConstr :: Alt f a -> Constr # dataTypeOf :: Alt f a -> DataType # dataCast1 :: Typeable t => (forall d. Data d => c (t d)) -> Maybe (c (Alt f a)) # dataCast2 :: Typeable t => (forall d e. (Data d, Data e) => c (t d e)) -> Maybe (c (Alt f a)) # gmapT :: (forall b. Data b => b -> b) -> Alt f a -> Alt f a # gmapQl :: (r -> r' -> r) -> r -> (forall d. Data d => d -> r') -> Alt f a -> r # gmapQr :: (r' -> r -> r) -> r -> (forall d. Data d => d -> r') -> Alt f a -> r # gmapQ :: (forall d. Data d => d -> u) -> Alt f a -> [u] # gmapQi :: Int -> (forall d. Data d => d -> u) -> Alt f a -> u # gmapM :: Monad m => (forall d. Data d => d -> m d) -> Alt f a -> m (Alt f a) # gmapMp :: MonadPlus m => (forall d. Data d => d -> m d) -> Alt f a -> m (Alt f a) # gmapMo :: MonadPlus m => (forall d. Data d => d -> m d) -> Alt f a -> m (Alt f a) # | |
(Coercible a b, Data a, Data b) => Data (Coercion a b) | Since: base-4.7.0.0 |
Defined in Data.Data gfoldl :: (forall d b0. Data d => c (d -> b0) -> d -> c b0) -> (forall g. g -> c g) -> Coercion a b -> c (Coercion a b) # gunfold :: (forall b0 r. Data b0 => c (b0 -> r) -> c r) -> (forall r. r -> c r) -> Constr -> c (Coercion a b) # toConstr :: Coercion a b -> Constr # dataTypeOf :: Coercion a b -> DataType # dataCast1 :: Typeable t => (forall d. Data d => c (t d)) -> Maybe (c (Coercion a b)) # dataCast2 :: Typeable t => (forall d e. (Data d, Data e) => c (t d e)) -> Maybe (c (Coercion a b)) # gmapT :: (forall b0. Data b0 => b0 -> b0) -> Coercion a b -> Coercion a b # gmapQl :: (r -> r' -> r) -> r -> (forall d. Data d => d -> r') -> Coercion a b -> r # gmapQr :: (r' -> r -> r) -> r -> (forall d. Data d => d -> r') -> Coercion a b -> r # gmapQ :: (forall d. Data d => d -> u) -> Coercion a b -> [u] # gmapQi :: Int -> (forall d. Data d => d -> u) -> Coercion a b -> u # gmapM :: Monad m => (forall d. Data d => d -> m d) -> Coercion a b -> m (Coercion a b) # gmapMp :: MonadPlus m => (forall d. Data d => d -> m d) -> Coercion a b -> m (Coercion a b) # gmapMo :: MonadPlus m => (forall d. Data d => d -> m d) -> Coercion a b -> m (Coercion a b) # | |
(a ~ b, Data a) => Data (a :~: b) | Since: base-4.7.0.0 |
Defined in Data.Data gfoldl :: (forall d b0. Data d => c (d -> b0) -> d -> c b0) -> (forall g. g -> c g) -> (a :~: b) -> c (a :~: b) # gunfold :: (forall b0 r. Data b0 => c (b0 -> r) -> c r) -> (forall r. r -> c r) -> Constr -> c (a :~: b) # toConstr :: (a :~: b) -> Constr # dataTypeOf :: (a :~: b) -> DataType # dataCast1 :: Typeable t => (forall d. Data d => c (t d)) -> Maybe (c (a :~: b)) # dataCast2 :: Typeable t => (forall d e. (Data d, Data e) => c (t d e)) -> Maybe (c (a :~: b)) # gmapT :: (forall b0. Data b0 => b0 -> b0) -> (a :~: b) -> a :~: b # gmapQl :: (r -> r' -> r) -> r -> (forall d. Data d => d -> r') -> (a :~: b) -> r # gmapQr :: (r' -> r -> r) -> r -> (forall d. Data d => d -> r') -> (a :~: b) -> r # gmapQ :: (forall d. Data d => d -> u) -> (a :~: b) -> [u] # gmapQi :: Int -> (forall d. Data d => d -> u) -> (a :~: b) -> u # gmapM :: Monad m => (forall d. Data d => d -> m d) -> (a :~: b) -> m (a :~: b) # gmapMp :: MonadPlus m => (forall d. Data d => d -> m d) -> (a :~: b) -> m (a :~: b) # gmapMo :: MonadPlus m => (forall d. Data d => d -> m d) -> (a :~: b) -> m (a :~: b) # | |
(Typeable i, Data p, Data c) => Data (K1 i c p) | Since: base-4.9.0.0 |
Defined in Data.Data gfoldl :: (forall d b. Data d => c0 (d -> b) -> d -> c0 b) -> (forall g. g -> c0 g) -> K1 i c p -> c0 (K1 i c p) # gunfold :: (forall b r. Data b => c0 (b -> r) -> c0 r) -> (forall r. r -> c0 r) -> Constr -> c0 (K1 i c p) # toConstr :: K1 i c p -> Constr # dataTypeOf :: K1 i c p -> DataType # dataCast1 :: Typeable t => (forall d. Data d => c0 (t d)) -> Maybe (c0 (K1 i c p)) # dataCast2 :: Typeable t => (forall d e. (Data d, Data e) => c0 (t d e)) -> Maybe (c0 (K1 i c p)) # gmapT :: (forall b. Data b => b -> b) -> K1 i c p -> K1 i c p # gmapQl :: (r -> r' -> r) -> r -> (forall d. Data d => d -> r') -> K1 i c p -> r # gmapQr :: (r' -> r -> r) -> r -> (forall d. Data d => d -> r') -> K1 i c p -> r # gmapQ :: (forall d. Data d => d -> u) -> K1 i c p -> [u] # gmapQi :: Int -> (forall d. Data d => d -> u) -> K1 i c p -> u # gmapM :: Monad m => (forall d. Data d => d -> m d) -> K1 i c p -> m (K1 i c p) # gmapMp :: MonadPlus m => (forall d. Data d => d -> m d) -> K1 i c p -> m (K1 i c p) # gmapMo :: MonadPlus m => (forall d. Data d => d -> m d) -> K1 i c p -> m (K1 i c p) # | |
(Typeable f, Typeable g, Data p, Data (f p), Data (g p)) => Data ((f :+: g) p) | Since: base-4.9.0.0 |
Defined in Data.Data gfoldl :: (forall d b. Data d => c (d -> b) -> d -> c b) -> (forall g0. g0 -> c g0) -> (f :+: g) p -> c ((f :+: g) p) # gunfold :: (forall b r. Data b => c (b -> r) -> c r) -> (forall r. r -> c r) -> Constr -> c ((f :+: g) p) # toConstr :: (f :+: g) p -> Constr # dataTypeOf :: (f :+: g) p -> DataType # dataCast1 :: Typeable t => (forall d. Data d => c (t d)) -> Maybe (c ((f :+: g) p)) # dataCast2 :: Typeable t => (forall d e. (Data d, Data e) => c (t d e)) -> Maybe (c ((f :+: g) p)) # gmapT :: (forall b. Data b => b -> b) -> (f :+: g) p -> (f :+: g) p # gmapQl :: (r -> r' -> r) -> r -> (forall d. Data d => d -> r') -> (f :+: g) p -> r # gmapQr :: (r' -> r -> r) -> r -> (forall d. Data d => d -> r') -> (f :+: g) p -> r # gmapQ :: (forall d. Data d => d -> u) -> (f :+: g) p -> [u] # gmapQi :: Int -> (forall d. Data d => d -> u) -> (f :+: g) p -> u # gmapM :: Monad m => (forall d. Data d => d -> m d) -> (f :+: g) p -> m ((f :+: g) p) # gmapMp :: MonadPlus m => (forall d. Data d => d -> m d) -> (f :+: g) p -> m ((f :+: g) p) # gmapMo :: MonadPlus m => (forall d. Data d => d -> m d) -> (f :+: g) p -> m ((f :+: g) p) # | |
(Typeable f, Typeable g, Data p, Data (f p), Data (g p)) => Data ((f :*: g) p) | Since: base-4.9.0.0 |
Defined in Data.Data gfoldl :: (forall d b. Data d => c (d -> b) -> d -> c b) -> (forall g0. g0 -> c g0) -> (f :*: g) p -> c ((f :*: g) p) # gunfold :: (forall b r. Data b => c (b -> r) -> c r) -> (forall r. r -> c r) -> Constr -> c ((f :*: g) p) # toConstr :: (f :*: g) p -> Constr # dataTypeOf :: (f :*: g) p -> DataType # dataCast1 :: Typeable t => (forall d. Data d => c (t d)) -> Maybe (c ((f :*: g) p)) # dataCast2 :: Typeable t => (forall d e. (Data d, Data e) => c (t d e)) -> Maybe (c ((f :*: g) p)) # gmapT :: (forall b. Data b => b -> b) -> (f :*: g) p -> (f :*: g) p # gmapQl :: (r -> r' -> r) -> r -> (forall d. Data d => d -> r') -> (f :*: g) p -> r # gmapQr :: (r' -> r -> r) -> r -> (forall d. Data d => d -> r') -> (f :*: g) p -> r # gmapQ :: (forall d. Data d => d -> u) -> (f :*: g) p -> [u] # gmapQi :: Int -> (forall d. Data d => d -> u) -> (f :*: g) p -> u # gmapM :: Monad m => (forall d. Data d => d -> m d) -> (f :*: g) p -> m ((f :*: g) p) # gmapMp :: MonadPlus m => (forall d. Data d => d -> m d) -> (f :*: g) p -> m ((f :*: g) p) # gmapMo :: MonadPlus m => (forall d. Data d => d -> m d) -> (f :*: g) p -> m ((f :*: g) p) # | |
(Data a, Data b, Data c, Data d) => Data (a, b, c, d) | Since: base-4.0.0.0 |
Defined in Data.Data gfoldl :: (forall d0 b0. Data d0 => c0 (d0 -> b0) -> d0 -> c0 b0) -> (forall g. g -> c0 g) -> (a, b, c, d) -> c0 (a, b, c, d) # gunfold :: (forall b0 r. Data b0 => c0 (b0 -> r) -> c0 r) -> (forall r. r -> c0 r) -> Constr -> c0 (a, b, c, d) # toConstr :: (a, b, c, d) -> Constr # dataTypeOf :: (a, b, c, d) -> DataType # dataCast1 :: Typeable t => (forall d0. Data d0 => c0 (t d0)) -> Maybe (c0 (a, b, c, d)) # dataCast2 :: Typeable t => (forall d0 e. (Data d0, Data e) => c0 (t d0 e)) -> Maybe (c0 (a, b, c, d)) # gmapT :: (forall b0. Data b0 => b0 -> b0) -> (a, b, c, d) -> (a, b, c, d) # gmapQl :: (r -> r' -> r) -> r -> (forall d0. Data d0 => d0 -> r') -> (a, b, c, d) -> r # gmapQr :: (r' -> r -> r) -> r -> (forall d0. Data d0 => d0 -> r') -> (a, b, c, d) -> r # gmapQ :: (forall d0. Data d0 => d0 -> u) -> (a, b, c, d) -> [u] # gmapQi :: Int -> (forall d0. Data d0 => d0 -> u) -> (a, b, c, d) -> u # gmapM :: Monad m => (forall d0. Data d0 => d0 -> m d0) -> (a, b, c, d) -> m (a, b, c, d) # gmapMp :: MonadPlus m => (forall d0. Data d0 => d0 -> m d0) -> (a, b, c, d) -> m (a, b, c, d) # gmapMo :: MonadPlus m => (forall d0. Data d0 => d0 -> m d0) -> (a, b, c, d) -> m (a, b, c, d) # | |
(Typeable i, Typeable j, Typeable a, Typeable b, a ~~ b) => Data (a :~~: b) | Since: base-4.10.0.0 |
Defined in Data.Data gfoldl :: (forall d b0. Data d => c (d -> b0) -> d -> c b0) -> (forall g. g -> c g) -> (a :~~: b) -> c (a :~~: b) # gunfold :: (forall b0 r. Data b0 => c (b0 -> r) -> c r) -> (forall r. r -> c r) -> Constr -> c (a :~~: b) # toConstr :: (a :~~: b) -> Constr # dataTypeOf :: (a :~~: b) -> DataType # dataCast1 :: Typeable t => (forall d. Data d => c (t d)) -> Maybe (c (a :~~: b)) # dataCast2 :: Typeable t => (forall d e. (Data d, Data e) => c (t d e)) -> Maybe (c (a :~~: b)) # gmapT :: (forall b0. Data b0 => b0 -> b0) -> (a :~~: b) -> a :~~: b # gmapQl :: (r -> r' -> r) -> r -> (forall d. Data d => d -> r') -> (a :~~: b) -> r # gmapQr :: (r' -> r -> r) -> r -> (forall d. Data d => d -> r') -> (a :~~: b) -> r # gmapQ :: (forall d. Data d => d -> u) -> (a :~~: b) -> [u] # gmapQi :: Int -> (forall d. Data d => d -> u) -> (a :~~: b) -> u # gmapM :: Monad m => (forall d. Data d => d -> m d) -> (a :~~: b) -> m (a :~~: b) # gmapMp :: MonadPlus m => (forall d. Data d => d -> m d) -> (a :~~: b) -> m (a :~~: b) # gmapMo :: MonadPlus m => (forall d. Data d => d -> m d) -> (a :~~: b) -> m (a :~~: b) # | |
(Data p, Data (f p), Typeable c, Typeable i, Typeable f) => Data (M1 i c f p) | Since: base-4.9.0.0 |
Defined in Data.Data gfoldl :: (forall d b. Data d => c0 (d -> b) -> d -> c0 b) -> (forall g. g -> c0 g) -> M1 i c f p -> c0 (M1 i c f p) # gunfold :: (forall b r. Data b => c0 (b -> r) -> c0 r) -> (forall r. r -> c0 r) -> Constr -> c0 (M1 i c f p) # toConstr :: M1 i c f p -> Constr # dataTypeOf :: M1 i c f p -> DataType # dataCast1 :: Typeable t => (forall d. Data d => c0 (t d)) -> Maybe (c0 (M1 i c f p)) # dataCast2 :: Typeable t => (forall d e. (Data d, Data e) => c0 (t d e)) -> Maybe (c0 (M1 i c f p)) # gmapT :: (forall b. Data b => b -> b) -> M1 i c f p -> M1 i c f p # gmapQl :: (r -> r' -> r) -> r -> (forall d. Data d => d -> r') -> M1 i c f p -> r # gmapQr :: (r' -> r -> r) -> r -> (forall d. Data d => d -> r') -> M1 i c f p -> r # gmapQ :: (forall d. Data d => d -> u) -> M1 i c f p -> [u] # gmapQi :: Int -> (forall d. Data d => d -> u) -> M1 i c f p -> u # gmapM :: Monad m => (forall d. Data d => d -> m d) -> M1 i c f p -> m (M1 i c f p) # gmapMp :: MonadPlus m => (forall d. Data d => d -> m d) -> M1 i c f p -> m (M1 i c f p) # gmapMo :: MonadPlus m => (forall d. Data d => d -> m d) -> M1 i c f p -> m (M1 i c f p) # | |
(Typeable f, Typeable g, Data p, Data (f (g p))) => Data ((f :.: g) p) | Since: base-4.9.0.0 |
Defined in Data.Data gfoldl :: (forall d b. Data d => c (d -> b) -> d -> c b) -> (forall g0. g0 -> c g0) -> (f :.: g) p -> c ((f :.: g) p) # gunfold :: (forall b r. Data b => c (b -> r) -> c r) -> (forall r. r -> c r) -> Constr -> c ((f :.: g) p) # toConstr :: (f :.: g) p -> Constr # dataTypeOf :: (f :.: g) p -> DataType # dataCast1 :: Typeable t => (forall d. Data d => c (t d)) -> Maybe (c ((f :.: g) p)) # dataCast2 :: Typeable t => (forall d e. (Data d, Data e) => c (t d e)) -> Maybe (c ((f :.: g) p)) # gmapT :: (forall b. Data b => b -> b) -> (f :.: g) p -> (f :.: g) p # gmapQl :: (r -> r' -> r) -> r -> (forall d. Data d => d -> r') -> (f :.: g) p -> r # gmapQr :: (r' -> r -> r) -> r -> (forall d. Data d => d -> r') -> (f :.: g) p -> r # gmapQ :: (forall d. Data d => d -> u) -> (f :.: g) p -> [u] # gmapQi :: Int -> (forall d. Data d => d -> u) -> (f :.: g) p -> u # gmapM :: Monad m => (forall d. Data d => d -> m d) -> (f :.: g) p -> m ((f :.: g) p) # gmapMp :: MonadPlus m => (forall d. Data d => d -> m d) -> (f :.: g) p -> m ((f :.: g) p) # gmapMo :: MonadPlus m => (forall d. Data d => d -> m d) -> (f :.: g) p -> m ((f :.: g) p) # | |
(Data a, Data b, Data c, Data d, Data e) => Data (a, b, c, d, e) | Since: base-4.0.0.0 |
Defined in Data.Data gfoldl :: (forall d0 b0. Data d0 => c0 (d0 -> b0) -> d0 -> c0 b0) -> (forall g. g -> c0 g) -> (a, b, c, d, e) -> c0 (a, b, c, d, e) # gunfold :: (forall b0 r. Data b0 => c0 (b0 -> r) -> c0 r) -> (forall r. r -> c0 r) -> Constr -> c0 (a, b, c, d, e) # toConstr :: (a, b, c, d, e) -> Constr # dataTypeOf :: (a, b, c, d, e) -> DataType # dataCast1 :: Typeable t => (forall d0. Data d0 => c0 (t d0)) -> Maybe (c0 (a, b, c, d, e)) # dataCast2 :: Typeable t => (forall d0 e0. (Data d0, Data e0) => c0 (t d0 e0)) -> Maybe (c0 (a, b, c, d, e)) # gmapT :: (forall b0. Data b0 => b0 -> b0) -> (a, b, c, d, e) -> (a, b, c, d, e) # gmapQl :: (r -> r' -> r) -> r -> (forall d0. Data d0 => d0 -> r') -> (a, b, c, d, e) -> r # gmapQr :: (r' -> r -> r) -> r -> (forall d0. Data d0 => d0 -> r') -> (a, b, c, d, e) -> r # gmapQ :: (forall d0. Data d0 => d0 -> u) -> (a, b, c, d, e) -> [u] # gmapQi :: Int -> (forall d0. Data d0 => d0 -> u) -> (a, b, c, d, e) -> u # gmapM :: Monad m => (forall d0. Data d0 => d0 -> m d0) -> (a, b, c, d, e) -> m (a, b, c, d, e) # gmapMp :: MonadPlus m => (forall d0. Data d0 => d0 -> m d0) -> (a, b, c, d, e) -> m (a, b, c, d, e) # gmapMo :: MonadPlus m => (forall d0. Data d0 => d0 -> m d0) -> (a, b, c, d, e) -> m (a, b, c, d, e) # | |
(Data a, Data b, Data c, Data d, Data e, Data f) => Data (a, b, c, d, e, f) | Since: base-4.0.0.0 |
Defined in Data.Data gfoldl :: (forall d0 b0. Data d0 => c0 (d0 -> b0) -> d0 -> c0 b0) -> (forall g. g -> c0 g) -> (a, b, c, d, e, f) -> c0 (a, b, c, d, e, f) # gunfold :: (forall b0 r. Data b0 => c0 (b0 -> r) -> c0 r) -> (forall r. r -> c0 r) -> Constr -> c0 (a, b, c, d, e, f) # toConstr :: (a, b, c, d, e, f) -> Constr # dataTypeOf :: (a, b, c, d, e, f) -> DataType # dataCast1 :: Typeable t => (forall d0. Data d0 => c0 (t d0)) -> Maybe (c0 (a, b, c, d, e, f)) # dataCast2 :: Typeable t => (forall d0 e0. (Data d0, Data e0) => c0 (t d0 e0)) -> Maybe (c0 (a, b, c, d, e, f)) # gmapT :: (forall b0. Data b0 => b0 -> b0) -> (a, b, c, d, e, f) -> (a, b, c, d, e, f) # gmapQl :: (r -> r' -> r) -> r -> (forall d0. Data d0 => d0 -> r') -> (a, b, c, d, e, f) -> r # gmapQr :: (r' -> r -> r) -> r -> (forall d0. Data d0 => d0 -> r') -> (a, b, c, d, e, f) -> r # gmapQ :: (forall d0. Data d0 => d0 -> u) -> (a, b, c, d, e, f) -> [u] # gmapQi :: Int -> (forall d0. Data d0 => d0 -> u) -> (a, b, c, d, e, f) -> u # gmapM :: Monad m => (forall d0. Data d0 => d0 -> m d0) -> (a, b, c, d, e, f) -> m (a, b, c, d, e, f) # gmapMp :: MonadPlus m => (forall d0. Data d0 => d0 -> m d0) -> (a, b, c, d, e, f) -> m (a, b, c, d, e, f) # gmapMo :: MonadPlus m => (forall d0. Data d0 => d0 -> m d0) -> (a, b, c, d, e, f) -> m (a, b, c, d, e, f) # | |
(Data a, Data b, Data c, Data d, Data e, Data f, Data g) => Data (a, b, c, d, e, f, g) | Since: base-4.0.0.0 |
Defined in Data.Data gfoldl :: (forall d0 b0. Data d0 => c0 (d0 -> b0) -> d0 -> c0 b0) -> (forall g0. g0 -> c0 g0) -> (a, b, c, d, e, f, g) -> c0 (a, b, c, d, e, f, g) # gunfold :: (forall b0 r. Data b0 => c0 (b0 -> r) -> c0 r) -> (forall r. r -> c0 r) -> Constr -> c0 (a, b, c, d, e, f, g) # toConstr :: (a, b, c, d, e, f, g) -> Constr # dataTypeOf :: (a, b, c, d, e, f, g) -> DataType # dataCast1 :: Typeable t => (forall d0. Data d0 => c0 (t d0)) -> Maybe (c0 (a, b, c, d, e, f, g)) # dataCast2 :: Typeable t => (forall d0 e0. (Data d0, Data e0) => c0 (t d0 e0)) -> Maybe (c0 (a, b, c, d, e, f, g)) # gmapT :: (forall b0. Data b0 => b0 -> b0) -> (a, b, c, d, e, f, g) -> (a, b, c, d, e, f, g) # gmapQl :: (r -> r' -> r) -> r -> (forall d0. Data d0 => d0 -> r') -> (a, b, c, d, e, f, g) -> r # gmapQr :: (r' -> r -> r) -> r -> (forall d0. Data d0 => d0 -> r') -> (a, b, c, d, e, f, g) -> r # gmapQ :: (forall d0. Data d0 => d0 -> u) -> (a, b, c, d, e, f, g) -> [u] # gmapQi :: Int -> (forall d0. Data d0 => d0 -> u) -> (a, b, c, d, e, f, g) -> u # gmapM :: Monad m => (forall d0. Data d0 => d0 -> m d0) -> (a, b, c, d, e, f, g) -> m (a, b, c, d, e, f, g) # gmapMp :: MonadPlus m => (forall d0. Data d0 => d0 -> m d0) -> (a, b, c, d, e, f, g) -> m (a, b, c, d, e, f, g) # gmapMo :: MonadPlus m => (forall d0. Data d0 => d0 -> m d0) -> (a, b, c, d, e, f, g) -> m (a, b, c, d, e, f, g) # |
The class Typeable
allows a concrete representation of a type to
be calculated.
typeRep#
Representable types of kind *
.
This class is derivable in GHC with the DeriveGeneric
flag on.
A Generic
instance must satisfy the following laws:
from
.to
≡id
to
.from
≡id
Instances
List operations
drop
n xs
returns the suffix of xs
after the first n
elements, or []
if n >
:length
xs
drop 6 "Hello World!" == "World!" drop 3 [1,2,3,4,5] == [4,5] drop 3 [1,2] == [] drop 3 [] == [] drop (-1) [1,2] == [1,2] drop 0 [1,2] == [1,2]
It is an instance of the more general genericDrop
,
in which n
may be of any integral type.
take
n
, applied to a list xs
, returns the prefix of xs
of length n
, or xs
itself if n >
:length
xs
take 5 "Hello World!" == "Hello" take 3 [1,2,3,4,5] == [1,2,3] take 3 [1,2] == [1,2] take 3 [] == [] take (-1) [1,2] == [] take 0 [1,2] == []
It is an instance of the more general genericTake
,
in which n
may be of any integral type.
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] == []
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],[])
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])
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 (
when take
n xs, drop
n xs)n
is not _|_
(splitAt _|_ xs = _|_
).
splitAt
is an instance of the more general genericSplitAt
,
in which n
may be of any integral type.
filter :: (a -> Bool) -> [a] -> [a] #
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]
lookup :: Eq a => a -> [(a, b)] -> Maybe b #
lookup
key assocs
looks up a key in an association list.
partition :: (a -> Bool) -> [a] -> ([a], [a]) #
The partition
function takes a predicate a list and returns
the pair of lists of elements which do and do not satisfy the
predicate, respectively; i.e.,
partition p xs == (filter p xs, filter (not . p) xs)
>>>
partition (`elem` "aeiou") "Hello World!"
("eoo","Hll Wrld!")
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.
intersperse :: a -> [a] -> [a] #
The intersperse
function takes an element and a list and
`intersperses' that element between the elements of the list.
For example,
>>>
intersperse ',' "abcde"
"a,b,c,d,e"
intercalate :: [a] -> [[a]] -> [a] #
intercalate
xs xss
is equivalent to (
.
It inserts the list concat
(intersperse
xs xss))xs
in between the lists in xss
and concatenates the
result.
>>>
intercalate ", " ["Lorem", "ipsum", "dolor"]
"Lorem, ipsum, dolor"
Zipping
zipWith7 :: (a -> b -> c -> d -> e -> f -> g -> h) -> [a] -> [b] -> [c] -> [d] -> [e] -> [f] -> [g] -> [h] #
unzip :: [(a, b)] -> ([a], [b]) #
unzip
transforms a list of pairs into a list of first components
and a list of second components.
NonEmpty
lists
Non-empty (and non-strict) list type.
Since: base-4.9.0.0
a :| [a] infixr 5 |
Instances
Monad NonEmpty | Since: base-4.9.0.0 |
Functor NonEmpty | Since: base-4.9.0.0 |
Applicative NonEmpty | Since: base-4.9.0.0 |
Foldable NonEmpty | Since: base-4.9.0.0 |
Defined in Data.Foldable fold :: Monoid m => NonEmpty m -> m # foldMap :: Monoid m => (a -> m) -> NonEmpty a -> m # foldr :: (a -> b -> b) -> b -> NonEmpty a -> b # foldr' :: (a -> b -> b) -> b -> NonEmpty a -> b # foldl :: (b -> a -> b) -> b -> NonEmpty a -> b # foldl' :: (b -> a -> b) -> b -> NonEmpty a -> b # foldr1 :: (a -> a -> a) -> NonEmpty a -> a # foldl1 :: (a -> a -> a) -> NonEmpty a -> a # elem :: Eq a => a -> NonEmpty a -> Bool # maximum :: Ord a => NonEmpty a -> a # minimum :: Ord a => NonEmpty a -> a # | |
Traversable NonEmpty | Since: base-4.9.0.0 |
Eq a => Eq (NonEmpty a) | |
Data a => Data (NonEmpty a) | Since: base-4.9.0.0 |
Defined in Data.Data gfoldl :: (forall d b. Data d => c (d -> b) -> d -> c b) -> (forall g. g -> c g) -> NonEmpty a -> c (NonEmpty a) # gunfold :: (forall b r. Data b => c (b -> r) -> c r) -> (forall r. r -> c r) -> Constr -> c (NonEmpty a) # toConstr :: NonEmpty a -> Constr # dataTypeOf :: NonEmpty a -> DataType # dataCast1 :: Typeable t => (forall d. Data d => c (t d)) -> Maybe (c (NonEmpty a)) # dataCast2 :: Typeable t => (forall d e. (Data d, Data e) => c (t d e)) -> Maybe (c (NonEmpty a)) # gmapT :: (forall b. Data b => b -> b) -> NonEmpty a -> NonEmpty a # gmapQl :: (r -> r' -> r) -> r -> (forall d. Data d => d -> r') -> NonEmpty a -> r # gmapQr :: (r' -> r -> r) -> r -> (forall d. Data d => d -> r') -> NonEmpty a -> r # gmapQ :: (forall d. Data d => d -> u) -> NonEmpty a -> [u] # gmapQi :: Int -> (forall d. Data d => d -> u) -> NonEmpty a -> u # gmapM :: Monad m => (forall d. Data d => d -> m d) -> NonEmpty a -> m (NonEmpty a) # gmapMp :: MonadPlus m => (forall d. Data d => d -> m d) -> NonEmpty a -> m (NonEmpty a) # gmapMo :: MonadPlus m => (forall d. Data d => d -> m d) -> NonEmpty a -> m (NonEmpty a) # | |
Ord a => Ord (NonEmpty a) | |
Read a => Read (NonEmpty a) | |
Show a => Show (NonEmpty a) | |
Generic (NonEmpty a) | |
Semigroup (NonEmpty a) | Since: base-4.9.0.0 |
Generic1 NonEmpty | |
type Rep (NonEmpty a) | |
Defined in GHC.Generics type Rep (NonEmpty a) = D1 (MetaData "NonEmpty" "GHC.Base" "base" False) (C1 (MetaCons ":|" (InfixI LeftAssociative 9) False) (S1 (MetaSel (Nothing :: Maybe Symbol) NoSourceUnpackedness NoSourceStrictness DecidedLazy) (Rec0 a) :*: S1 (MetaSel (Nothing :: Maybe Symbol) NoSourceUnpackedness NoSourceStrictness DecidedLazy) (Rec0 [a]))) | |
type Rep1 NonEmpty | |
Defined in GHC.Generics type Rep1 NonEmpty = D1 (MetaData "NonEmpty" "GHC.Base" "base" False) (C1 (MetaCons ":|" (InfixI LeftAssociative 9) False) (S1 (MetaSel (Nothing :: Maybe Symbol) NoSourceUnpackedness NoSourceStrictness DecidedLazy) Par1 :*: S1 (MetaSel (Nothing :: Maybe Symbol) NoSourceUnpackedness NoSourceStrictness DecidedLazy) (Rec1 []))) |
Read
and Show
Conversion of values to readable String
s.
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 thand
(associativity is ignored). Thus, ifd
is0
then the result is never surrounded in parentheses; ifd
is11
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,
produces the stringshow
(Leaf 1 :^: Leaf 2 :^: Leaf 3)"Leaf 1 :^: (Leaf 2 :^: Leaf 3)"
.
:: Int | the operator precedence of the enclosing
context (a number from |
-> a | the value to be converted to a |
-> 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.
Instances
Show Bool | |
Show Char | Since: base-2.1 |
Show Int | Since: base-2.1 |
Show Int8 | Since: base-2.1 |
Show Int16 | Since: base-2.1 |
Show Int32 | Since: base-2.1 |
Show Int64 | Since: base-2.1 |
Show Integer | Since: base-2.1 |
Show Ordering | |
Show Word | Since: base-2.1 |
Show Word8 | Since: base-2.1 |
Show Word16 | Since: base-2.1 |
Show Word32 | Since: base-2.1 |
Show Word64 | Since: base-2.1 |
Show RuntimeRep | |
Defined in GHC.Show showsPrec :: Int -> RuntimeRep -> ShowS # show :: RuntimeRep -> String # showList :: [RuntimeRep] -> ShowS # | |
Show VecCount | |
Show VecElem | |
Show CallStack | Since: base-4.9.0.0 |
Show SomeTypeRep | Since: base-4.10.0.0 |
Defined in Data.Typeable.Internal showsPrec :: Int -> SomeTypeRep -> ShowS # show :: SomeTypeRep -> String # showList :: [SomeTypeRep] -> ShowS # | |
Show () | |
Show TyCon | Since: base-2.1 |
Show Module | Since: base-4.9.0.0 |
Show TrName | Since: base-4.9.0.0 |
Show KindRep | |
Show TypeLitSort | |
Defined in GHC.Show showsPrec :: Int -> TypeLitSort -> ShowS # show :: TypeLitSort -> String # showList :: [TypeLitSort] -> ShowS # | |
Show HandleType | Since: base-4.1.0.0 |
Show DataType | |
Show Constr | Since: base-4.0.0.0 |
Show DataRep | |
Show ConstrRep | |
Show Fixity | |
Show HandlePosn | Since: base-4.1.0.0 |
Defined in GHC.IO.Handle showsPrec :: Int -> HandlePosn -> ShowS # show :: HandlePosn -> String # showList :: [HandlePosn] -> ShowS # | |
Show Handle | Since: base-4.1.0.0 |
Show BufferMode | |
Defined in GHC.IO.Handle.Types showsPrec :: Int -> BufferMode -> ShowS # show :: BufferMode -> String # showList :: [BufferMode] -> ShowS # | |
Show Newline | |
Show NewlineMode | |
Defined in GHC.IO.Handle.Types showsPrec :: Int -> NewlineMode -> ShowS # show :: NewlineMode -> String # showList :: [NewlineMode] -> ShowS # | |
Show SeekMode | |
Show TextEncoding | Since: base-4.3.0.0 |
Defined in GHC.IO.Encoding.Types showsPrec :: Int -> TextEncoding -> ShowS # show :: TextEncoding -> String # showList :: [TextEncoding] -> ShowS # | |
Show CodingProgress | |
Defined in GHC.IO.Encoding.Types showsPrec :: Int -> CodingProgress -> ShowS # show :: CodingProgress -> String # showList :: [CodingProgress] -> ShowS # | |
Show MaskingState | |
Defined in GHC.IO showsPrec :: Int -> MaskingState -> ShowS # show :: MaskingState -> String # showList :: [MaskingState] -> ShowS # | |
Show All | |
Show Any | |
Show Fixity | |
Show Associativity | |
Defined in GHC.Generics showsPrec :: Int -> Associativity -> ShowS # show :: Associativity -> String # showList :: [Associativity] -> ShowS # | |
Show SourceUnpackedness | |
Defined in GHC.Generics showsPrec :: Int -> SourceUnpackedness -> ShowS # show :: SourceUnpackedness -> String # showList :: [SourceUnpackedness] -> ShowS # | |
Show SourceStrictness | |
Defined in GHC.Generics showsPrec :: Int -> SourceStrictness -> ShowS # show :: SourceStrictness -> String # showList :: [SourceStrictness] -> ShowS # | |
Show DecidedStrictness | |
Defined in GHC.Generics showsPrec :: Int -> DecidedStrictness -> ShowS # show :: DecidedStrictness -> String # showList :: [DecidedStrictness] -> ShowS # | |
Show IOMode | |
Show Lexeme | |
Show Number | |
Show GeneralCategory | |
Defined in GHC.Unicode showsPrec :: Int -> GeneralCategory -> ShowS # show :: GeneralCategory -> String # showList :: [GeneralCategory] -> ShowS # | |
Show SrcLoc | |
Show a => Show [a] | Since: base-2.1 |
Show a => Show (Maybe a) | |
Show a => Show (Ratio a) | Since: base-2.0.1 |
Show p => Show (Par1 p) | |
Show a => Show (Min a) | |
Show a => Show (Max a) | |
Show a => Show (First a) | |
Show a => Show (Last a) | |
Show m => Show (WrappedMonoid m) | |
Defined in Data.Semigroup showsPrec :: Int -> WrappedMonoid m -> ShowS # show :: WrappedMonoid m -> String # showList :: [WrappedMonoid m] -> ShowS # | |
Show a => Show (Option a) | |
Show a => Show (ZipList a) | |
Show a => Show (Dual a) | |
Show a => Show (Sum a) | |
Show a => Show (Product a) | |
Show a => Show (Down a) | Since: base-4.7.0.0 |
Show a => Show (NonEmpty a) | |
(Show a, Show b) => Show (Either a b) | |
Show (V1 p) | Since: base-4.9.0.0 |
Show (U1 p) | Since: base-4.9.0.0 |
Show (TypeRep a) | |
(Show a, Show b) => Show (a, b) | Since: base-2.1 |
(Ix a, Show a, Show b) => Show (Array a b) | Since: base-2.1 |
(Show a, Show b) => Show (Arg a b) | |
Show (f p) => Show (Rec1 f p) | |
Show (URec Char p) | |
Show (URec Double p) | |
Show (URec Float p) | |
Show (URec Int p) | |
Show (URec Word p) | |
(Show a, Show b, Show c) => Show (a, b, c) | Since: base-2.1 |
Show a => Show (Const a b) | This instance would be equivalent to the derived instances of the
Since: base-4.8.0.0 |
Show (f a) => Show (Alt f a) | |
Show c => Show (K1 i c p) | |
(Show (f p), Show (g p)) => Show ((f :+: g) p) | |
(Show (f p), Show (g p)) => Show ((f :*: g) p) | |
(Show a, Show b, Show c, Show d) => Show (a, b, c, d) | Since: base-2.1 |
Show (f p) => Show (M1 i c f p) | |
Show (f (g p)) => Show ((f :.: g) p) | |
(Show a, Show b, Show c, Show d, Show e) => Show (a, b, c, d, e) | Since: base-2.1 |
(Show a, Show b, Show c, Show d, Show e, Show f) => Show (a, b, c, d, e, f) | Since: base-2.1 |
(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 |
(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 |
(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 |
(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 |
(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 |
(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 |
(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 |
(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 |
(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 |
utility function converting a Char
to a show function that
simply prepends the character unchanged.
showString :: String -> ShowS #
utility function converting a String
to a show function that
simply prepends the string unchanged.
Parsing of String
s, 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:
instanceRead
T wherereadPrec
= ...readListPrec
=readListPrecDefault
:: Int | the operator precedence of the enclosing
context (a number from |
-> 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.
Instances
Read Bool | Since: base-2.1 |
Read Char | Since: base-2.1 |
Read Double | Since: base-2.1 |
Read Float | Since: base-2.1 |
Read Int | Since: base-2.1 |
Read Int8 | Since: base-2.1 |
Read Int16 | Since: base-2.1 |
Read Int32 | Since: base-2.1 |
Read Int64 | Since: base-2.1 |
Read Integer | Since: base-2.1 |
Read Ordering | Since: base-2.1 |
Read Word | Since: base-4.5.0.0 |
Read Word8 | Since: base-2.1 |
Read Word16 | Since: base-2.1 |
Read Word32 | Since: base-2.1 |
Read Word64 | Since: base-2.1 |
Read () | Since: base-2.1 |
Read BufferMode | |
Defined in GHC.IO.Handle.Types readsPrec :: Int -> ReadS BufferMode # readList :: ReadS [BufferMode] # readPrec :: ReadPrec BufferMode # readListPrec :: ReadPrec [BufferMode] # | |
Read Newline | |
Read NewlineMode | |
Defined in GHC.IO.Handle.Types readsPrec :: Int -> ReadS NewlineMode # readList :: ReadS [NewlineMode] # readPrec :: ReadPrec NewlineMode # readListPrec :: ReadPrec [NewlineMode] # | |
Read SeekMode | |
Read All | |
Read Any | |
Read Fixity | |
Read Associativity | |
Defined in GHC.Generics readsPrec :: Int -> ReadS Associativity # readList :: ReadS [Associativity] # | |
Read SourceUnpackedness | |
Defined in GHC.Generics | |
Read SourceStrictness | |
Defined in GHC.Generics | |
Read DecidedStrictness | |
Defined in GHC.Generics | |
Read IOMode | |
Read Lexeme | Since: base-2.1 |
Read GeneralCategory | |
Defined in GHC.Read | |
Read a => Read [a] | Since: base-2.1 |
Read a => Read (Maybe a) | Since: base-2.1 |
(Integral a, Read a) => Read (Ratio a) | Since: base-2.1 |
Read p => Read (Par1 p) | |
Read a => Read (Min a) | |
Read a => Read (Max a) | |
Read a => Read (First a) | |
Read a => Read (Last a) | |
Read m => Read (WrappedMonoid m) | |
Defined in Data.Semigroup readsPrec :: Int -> ReadS (WrappedMonoid m) # readList :: ReadS [WrappedMonoid m] # readPrec :: ReadPrec (WrappedMonoid m) # readListPrec :: ReadPrec [WrappedMonoid m] # | |
Read a => Read (Option a) | |
Read a => Read (ZipList a) | |
Read a => Read (Dual a) | |
Read a => Read (Sum a) | |
Read a => Read (Product a) | |
Read a => Read (Down a) | Since: base-4.7.0.0 |
Read a => Read (NonEmpty a) | |
(Read a, Read b) => Read (Either a b) | |
Read (V1 p) | Since: base-4.9.0.0 |
Read (U1 p) | Since: base-4.9.0.0 |
(Read a, Read b) => Read (a, b) | Since: base-2.1 |
(Ix a, Read a, Read b) => Read (Array a b) | Since: base-2.1 |
(Read a, Read b) => Read (Arg a b) | |
Read (f p) => Read (Rec1 f p) | |
(Read a, Read b, Read c) => Read (a, b, c) | Since: base-2.1 |
Read a => Read (Const a b) | This instance would be equivalent to the derived instances of the
Since: base-4.8.0.0 |
Read (f a) => Read (Alt f a) | |
Read c => Read (K1 i c p) | |
(Read (f p), Read (g p)) => Read ((f :+: g) p) | |
(Read (f p), Read (g p)) => Read ((f :*: g) p) | |
(Read a, Read b, Read c, Read d) => Read (a, b, c, d) | Since: base-2.1 |
Read (f p) => Read (M1 i c f p) | |
Read (f (g p)) => Read ((f :.: g) p) | |
(Read a, Read b, Read c, Read d, Read e) => Read (a, b, c, d, e) | Since: base-2.1 |
(Read a, Read b, Read c, Read d, Read e, Read f) => Read (a, b, c, d, e, f) | Since: base-2.1 |
(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 |
(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 |
(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 |
(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 |
(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 |
(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 |
(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 |
(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 |
(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 |
Defined in GHC.Read |
IO
and MonadIO
A value of type
is a computation which, when performed,
does some I/O before returning a value of type IO
aa
.
There is really only one way to "perform" an I/O action: bind it to
Main.main
in your program. When your program is run, the I/O will
be performed. It isn't possible to perform I/O from an arbitrary
function, unless that function is itself in the IO
monad and called
at some point, directly or indirectly, from Main.main
.
IO
is a monad, so IO
actions can be combined using either the do-notation
or the >>
and >>=
operations from the Monad
class.
Instances
Monad IO | Since: base-2.1 |
Functor IO | Since: base-2.1 |
MonadFail IO | Since: base-4.9.0.0 |
Defined in Control.Monad.Fail | |
Applicative IO | Since: base-2.1 |
MonadIO IO | Since: base-4.9.0.0 |
Defined in Control.Monad.IO.Class | |
Alternative IO | Since: base-4.9.0.0 |
MonadPlus IO | Since: base-4.9.0.0 |
Semigroup a => Semigroup (IO a) | Since: base-4.10.0.0 |
Monoid a => Monoid (IO a) | Since: base-4.9.0.0 |
Standard input/output
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]])
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
).
FilePath
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.
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
.
writeFile :: FilePath -> String -> IO () #
The computation writeFile
file str
function writes the string str
,
to the file file
.
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]])
Common miscellaneous verbs
const x
is a unary function which evaluates to x
for all inputs.
>>>
const 42 "hello"
42
>>>
map (const 42) [0..3]
[42,42,42,42]
flip :: (a -> b -> c) -> b -> a -> c #
takes its (first) two arguments in the reverse order of flip
ff
.
>>>
flip (++) "hello" "world"
"worldhello"
($) :: (a -> b) -> a -> b infixr 0 #
Application operator. This operator is redundant, since ordinary
application (f x)
means the same as (f
. However, $
x)$
has
low, right-associative binding precedence, so it sometimes allows
parentheses to be omitted; for example:
f $ g $ h x = f (g (h x))
It is also useful in higher-order situations, such as
,
or map
($
0) xs
.zipWith
($
) fs xs
($!) :: (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.
until :: (a -> Bool) -> (a -> a) -> a -> a #
yields the result of applying until
p ff
until p
holds.
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.
Intentionally partial functions
error :: HasCallStack => [Char] -> a #
error
stops execution and displays an error message.
errorWithoutStackTrace :: [Char] -> a #
A variant of error
that does not produce a stack trace.
Since: base-4.9.0.0
undefined :: HasCallStack => a #