base-4.10.1.0: Basic libraries

Copyright	(c) Andy Gill 2001 (c) Oregon Graduate Institute of Science and Technology 2001
License	BSD-style (see the file LICENSE)
Maintainer	ross@soi.city.ac.uk
Stability	experimental
Portability	portable
Safe Haskell	Trustworthy
Language	Haskell2010

Data.Functor.Identity

Description

The identity functor and monad.

This trivial type constructor serves two purposes:

It can be used with functions parameterized by functor or monad classes.
It can be used as a base monad to which a series of monad transformers may be applied to construct a composite monad. Most monad transformer modules include the special case of applying the transformer to Identity . For example, State s is an abbreviation for StateT s Identity .

Since: 4.8.0.0

Synopsis

newtype Identity a = Identity {
- runIdentity :: a
}

Documentation

newtype Identity a Source #

Identity functor and monad. (a non-strict monad)

Since: 4.8.0.0

Constructors

Fields

runIdentity :: a

Instances

Monad Identity Source #

Since: 4.8.0.0

Methods

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

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

return :: a -> Identity a Source #

fail :: String -> Identity a Source #

Functor Identity Source #

Since: 4.8.0.0

Methods

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

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

MonadFix Identity Source #

Since: 4.8.0.0

Methods

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

Applicative Identity Source #

Since: 4.8.0.0

Methods

pure :: a -> Identity a Source #

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

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

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

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

Foldable Identity Source #

Since: 4.8.0.0

Methods

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

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

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

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

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

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

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

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

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

null :: Identity a -> Bool Source #

length :: Identity a -> Int Source #

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

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

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

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

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

Traversable Identity Source #

Methods

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

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

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

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

MonadZip Identity Source #

Since: 4.8.0.0

Methods

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

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

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

Show1 Identity Source #

Since: 4.9.0.0

Methods

liftShowsPrec :: (Int -> a -> ShowS) -> ([a] -> ShowS) -> Int -> Identity a -> ShowS Source #

liftShowList :: (Int -> a -> ShowS) -> ([a] -> ShowS) -> [Identity a] -> ShowS Source #

Read1 Identity Source #

Since: 4.9.0.0

Methods

liftReadsPrec :: (Int -> ReadS a) -> ReadS [a] -> Int -> ReadS (Identity a) Source #

liftReadList :: (Int -> ReadS a) -> ReadS [a] -> ReadS [Identity a] Source #

liftReadPrec :: ReadPrec a -> ReadPrec [a] -> ReadPrec (Identity a) Source #

liftReadListPrec :: ReadPrec a -> ReadPrec [a] -> ReadPrec [Identity a] Source #

Ord1 Identity Source #

Since: 4.9.0.0

Methods

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

Eq1 Identity Source #

Since: 4.9.0.0

Methods

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

Bounded a => Bounded (Identity a) Source #

Methods

minBound :: Identity a Source #

maxBound :: Identity a Source #

Enum a => Enum (Identity a) Source #

Methods

succ :: Identity a -> Identity a Source #

pred :: Identity a -> Identity a Source #

toEnum :: Int -> Identity a Source #

fromEnum :: Identity a -> Int Source #

enumFrom :: Identity a -> [Identity a] Source #

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

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

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

Eq a => Eq (Identity a) Source #

Methods

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

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

Floating a => Floating (Identity a) Source #

Methods

pi :: Identity a Source #

exp :: Identity a -> Identity a Source #

log :: Identity a -> Identity a Source #

sqrt :: Identity a -> Identity a Source #

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

logBase :: Identity a -> Identity a -> Identity a Source #

sin :: Identity a -> Identity a Source #

cos :: Identity a -> Identity a Source #

tan :: Identity a -> Identity a Source #

asin :: Identity a -> Identity a Source #

acos :: Identity a -> Identity a Source #

atan :: Identity a -> Identity a Source #

sinh :: Identity a -> Identity a Source #

cosh :: Identity a -> Identity a Source #

tanh :: Identity a -> Identity a Source #

asinh :: Identity a -> Identity a Source #

acosh :: Identity a -> Identity a Source #

atanh :: Identity a -> Identity a Source #

log1p :: Identity a -> Identity a Source #

expm1 :: Identity a -> Identity a Source #

log1pexp :: Identity a -> Identity a Source #

log1mexp :: Identity a -> Identity a Source #

Fractional a => Fractional (Identity a) Source #

Methods

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

recip :: Identity a -> Identity a Source #

fromRational :: Rational -> Identity a Source #

Integral a => Integral (Identity a) Source #

Methods

quot :: Identity a -> Identity a -> Identity a Source #

rem :: Identity a -> Identity a -> Identity a Source #

div :: Identity a -> Identity a -> Identity a Source #

mod :: Identity a -> Identity a -> Identity a Source #

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

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

toInteger :: Identity a -> Integer Source #

Data a => Data (Identity a) Source #

Since: 4.9.0.0

Methods

gfoldl :: (forall d b. Data d => c (d -> b) -> d -> c b) -> (forall g. g -> c g) -> Identity a -> c (Identity a) Source #

gunfold :: (forall b r. Data b => c (b -> r) -> c r) -> (forall r. r -> c r) -> Constr -> c (Identity a) Source #

toConstr :: Identity a -> Constr Source #

dataTypeOf :: Identity a -> DataType Source #

dataCast1 :: Typeable (* -> *) t => (forall d. Data d => c (t d)) -> Maybe (c (Identity a)) Source #

dataCast2 :: Typeable (* -> * -> *) t => (forall d e. (Data d, Data e) => c (t d e)) -> Maybe (c (Identity a)) Source #

gmapT :: (forall b. Data b => b -> b) -> Identity a -> Identity a Source #

gmapQl :: (r -> r' -> r) -> r -> (forall d. Data d => d -> r') -> Identity a -> r Source #

gmapQr :: (r' -> r -> r) -> r -> (forall d. Data d => d -> r') -> Identity a -> r Source #

gmapQ :: (forall d. Data d => d -> u) -> Identity a -> [u] Source #

gmapQi :: Int -> (forall d. Data d => d -> u) -> Identity a -> u Source #

gmapM :: Monad m => (forall d. Data d => d -> m d) -> Identity a -> m (Identity a) Source #

gmapMp :: MonadPlus m => (forall d. Data d => d -> m d) -> Identity a -> m (Identity a) Source #

gmapMo :: MonadPlus m => (forall d. Data d => d -> m d) -> Identity a -> m (Identity a) Source #

Num a => Num (Identity a) Source #

Methods

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

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

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

negate :: Identity a -> Identity a Source #

abs :: Identity a -> Identity a Source #

signum :: Identity a -> Identity a Source #

fromInteger :: Integer -> Identity a Source #

Ord a => Ord (Identity a) Source #

Methods

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

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

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

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

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

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

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

Read a => Read (Identity a) Source #

This instance would be equivalent to the derived instances of the Identity newtype if the runIdentity field were removed

Since: 4.8.0.0

Methods

readsPrec :: Int -> ReadS (Identity a) Source #

readList :: ReadS [Identity a] Source #

readPrec :: ReadPrec (Identity a) Source #

readListPrec :: ReadPrec [Identity a] Source #

Real a => Real (Identity a) Source #

Methods

toRational :: Identity a -> Rational Source #

RealFloat a => RealFloat (Identity a) Source #

Methods

floatRadix :: Identity a -> Integer Source #

floatDigits :: Identity a -> Int Source #

floatRange :: Identity a -> (Int, Int) Source #

decodeFloat :: Identity a -> (Integer, Int) Source #

encodeFloat :: Integer -> Int -> Identity a Source #

exponent :: Identity a -> Int Source #

significand :: Identity a -> Identity a Source #

scaleFloat :: Int -> Identity a -> Identity a Source #

isNaN :: Identity a -> Bool Source #

isInfinite :: Identity a -> Bool Source #

isDenormalized :: Identity a -> Bool Source #

isNegativeZero :: Identity a -> Bool Source #

isIEEE :: Identity a -> Bool Source #

atan2 :: Identity a -> Identity a -> Identity a Source #

RealFrac a => RealFrac (Identity a) Source #

Methods

properFraction :: Integral b => Identity a -> (b, Identity a) Source #

truncate :: Integral b => Identity a -> b Source #

round :: Integral b => Identity a -> b Source #

ceiling :: Integral b => Identity a -> b Source #

floor :: Integral b => Identity a -> b Source #

Show a => Show (Identity a) Source #

This instance would be equivalent to the derived instances of the Identity newtype if the runIdentity field were removed

Since: 4.8.0.0

Methods

showsPrec :: Int -> Identity a -> ShowS Source #

show :: Identity a -> String Source #

showList :: [Identity a] -> ShowS Source #

Ix a => Ix (Identity a) Source #

Methods

range :: (Identity a, Identity a) -> [Identity a] Source #

index :: (Identity a, Identity a) -> Identity a -> Int Source #

unsafeIndex :: (Identity a, Identity a) -> Identity a -> Int

inRange :: (Identity a, Identity a) -> Identity a -> Bool Source #

rangeSize :: (Identity a, Identity a) -> Int Source #

unsafeRangeSize :: (Identity a, Identity a) -> Int

IsString a => IsString (Identity a) Source #

Methods

fromString :: String -> Identity a Source #

Generic (Identity a) Source #

Associated Types

type Rep (Identity a) :: * -> * Source #

Methods

from :: Identity a -> Rep (Identity a) x Source #

to :: Rep (Identity a) x -> Identity a Source #

Semigroup a => Semigroup (Identity a) Source #

Since: 4.9.0.0

Methods

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

sconcat :: NonEmpty (Identity a) -> Identity a Source #

stimes :: Integral b => b -> Identity a -> Identity a Source #

Monoid a => Monoid (Identity a) Source #

Methods

mempty :: Identity a Source #

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

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

FiniteBits a => FiniteBits (Identity a) Source #

Methods

finiteBitSize :: Identity a -> Int Source #

countLeadingZeros :: Identity a -> Int Source #

countTrailingZeros :: Identity a -> Int Source #

Bits a => Bits (Identity a) Source #

Methods

(.&.) :: Identity a -> Identity a -> Identity a Source #

(.|.) :: Identity a -> Identity a -> Identity a Source #

xor :: Identity a -> Identity a -> Identity a Source #

complement :: Identity a -> Identity a Source #

shift :: Identity a -> Int -> Identity a Source #

rotate :: Identity a -> Int -> Identity a Source #

zeroBits :: Identity a Source #

bit :: Int -> Identity a Source #

setBit :: Identity a -> Int -> Identity a Source #

clearBit :: Identity a -> Int -> Identity a Source #

complementBit :: Identity a -> Int -> Identity a Source #

testBit :: Identity a -> Int -> Bool Source #

bitSizeMaybe :: Identity a -> Maybe Int Source #

bitSize :: Identity a -> Int Source #

isSigned :: Identity a -> Bool Source #

shiftL :: Identity a -> Int -> Identity a Source #

unsafeShiftL :: Identity a -> Int -> Identity a Source #

shiftR :: Identity a -> Int -> Identity a Source #

unsafeShiftR :: Identity a -> Int -> Identity a Source #

rotateL :: Identity a -> Int -> Identity a Source #

rotateR :: Identity a -> Int -> Identity a Source #

popCount :: Identity a -> Int Source #

Storable a => Storable (Identity a) Source #

Methods

sizeOf :: Identity a -> Int Source #

alignment :: Identity a -> Int Source #

peekElemOff :: Ptr (Identity a) -> Int -> IO (Identity a) Source #

pokeElemOff :: Ptr (Identity a) -> Int -> Identity a -> IO () Source #

peekByteOff :: Ptr b -> Int -> IO (Identity a) Source #

pokeByteOff :: Ptr b -> Int -> Identity a -> IO () Source #

peek :: Ptr (Identity a) -> IO (Identity a) Source #

poke :: Ptr (Identity a) -> Identity a -> IO () Source #

Generic1 * Identity Source #

Associated Types

type Rep1 Identity (f :: Identity -> *) :: k -> * Source #

Methods

from1 :: f a -> Rep1 Identity f a Source #

to1 :: Rep1 Identity f a -> f a Source #

type Rep (Identity a) Source #

type Rep (Identity a) = D1 * (MetaData "Identity" "Data.Functor.Identity" "base" True) (C1 * (MetaCons "Identity" PrefixI True) (S1 * (MetaSel (Just Symbol "runIdentity") NoSourceUnpackedness NoSourceStrictness DecidedLazy) (Rec0 * a)))

type Rep1 * Identity Source #

type Rep1 * Identity = D1 * (MetaData "Identity" "Data.Functor.Identity" "base" True) (C1 * (MetaCons "Identity" PrefixI True) (S1 * (MetaSel (Just Symbol "runIdentity") NoSourceUnpackedness NoSourceStrictness DecidedLazy) Par1))