Safe Haskell	Safe
Language	Haskell2010

Data.Strict.Either

Description

The strict variant of the standard Haskell Either type and the corresponding variants of the functions from Data.Either.

Note that the strict Either type is not an applicative functor, and therefore also no monad. The reasons are the same as the ones for the strict Maybe type, which are explained in Data.Maybe.Strict.

Synopsis

data Either a b
- = Left !a
- | Right !b
either :: (a -> c) -> (b -> c) -> Either a b -> c
isLeft :: Either a b -> Bool
isRight :: Either a b -> Bool
fromLeft :: Either a b -> a
fromRight :: Either a b -> b
lefts :: [Either a b] -> [a]
rights :: [Either a b] -> [b]
partitionEithers :: [Either a b] -> ([a], [b])

Documentation

data Either a b Source #

The strict choice type.

Constructors

Left !a

Right !b

Instances

Instances details

Assoc Either Source #

Instance details

Defined in Data.Strict.Either

Methods

assoc :: Either (Either a b) c -> Either a (Either b c) #

unassoc :: Either a (Either b c) -> Either (Either a b) c #

Swap Either Source #

Instance details

Defined in Data.Strict.Either

Methods

swap :: Either a b -> Either b a #

Bifoldable Either Source #

Instance details

Defined in Data.Strict.Either

Methods

bifold :: Monoid m => Either m m -> m #

bifoldMap :: Monoid m => (a -> m) -> (b -> m) -> Either a b -> m #

bifoldr :: (a -> c -> c) -> (b -> c -> c) -> c -> Either a b -> c #

bifoldl :: (c -> a -> c) -> (c -> b -> c) -> c -> Either a b -> c #

Bifunctor Either Source #

Instance details

Defined in Data.Strict.Either

Methods

bimap :: (a -> b) -> (c -> d) -> Either a c -> Either b d #

first :: (a -> b) -> Either a c -> Either b c #

second :: (b -> c) -> Either a b -> Either a c #

Bitraversable Either Source #

Instance details

Defined in Data.Strict.Either

Methods

bitraverse :: Applicative f => (a -> f c) -> (b -> f d) -> Either a b -> f (Either c d) #

Eq2 Either Source #

Instance details

Defined in Data.Strict.Either

Methods

liftEq2 :: (a -> b -> Bool) -> (c -> d -> Bool) -> Either a c -> Either b d -> Bool #

Ord2 Either Source #

Instance details

Defined in Data.Strict.Either

Methods

liftCompare2 :: (a -> b -> Ordering) -> (c -> d -> Ordering) -> Either a c -> Either b d -> Ordering #

Read2 Either Source #

Instance details

Defined in Data.Strict.Either

Methods

liftReadsPrec2 :: (Int -> ReadS a) -> ReadS [a] -> (Int -> ReadS b) -> ReadS [b] -> Int -> ReadS (Either a b) #

liftReadList2 :: (Int -> ReadS a) -> ReadS [a] -> (Int -> ReadS b) -> ReadS [b] -> ReadS [Either a b] #

liftReadPrec2 :: ReadPrec a -> ReadPrec [a] -> ReadPrec b -> ReadPrec [b] -> ReadPrec (Either a b) #

liftReadListPrec2 :: ReadPrec a -> ReadPrec [a] -> ReadPrec b -> ReadPrec [b] -> ReadPrec [Either a b] #

Show2 Either Source #

Instance details

Defined in Data.Strict.Either

Methods

liftShowsPrec2 :: (Int -> a -> ShowS) -> ([a] -> ShowS) -> (Int -> b -> ShowS) -> ([b] -> ShowS) -> Int -> Either a b -> ShowS #

liftShowList2 :: (Int -> a -> ShowS) -> ([a] -> ShowS) -> (Int -> b -> ShowS) -> ([b] -> ShowS) -> [Either a b] -> ShowS #

NFData2 Either Source #

Instance details

Defined in Data.Strict.Either

Methods

liftRnf2 :: (a -> ()) -> (b -> ()) -> Either a b -> () #

Hashable2 Either Source #

Instance details

Defined in Data.Strict.Either

Methods

liftHashWithSalt2 :: (Int -> a -> Int) -> (Int -> b -> Int) -> Int -> Either a b -> Int #

Generic1 (Either a :: Type -> Type) Source #

Instance details

Defined in Data.Strict.Either

Associated Types

type Rep1 (Either a) :: k -> Type #

Methods

from1 :: forall (a0 :: k). Either a a0 -> Rep1 (Either a) a0 #

to1 :: forall (a0 :: k). Rep1 (Either a) a0 -> Either a a0 #

Foldable (Either e) Source #

Instance details

Defined in Data.Strict.Either

Methods

fold :: Monoid m => Either e m -> m #

foldMap :: Monoid m => (a -> m) -> Either e a -> m #

foldMap' :: Monoid m => (a -> m) -> Either e a -> m #

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

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

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

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

foldr1 :: (a -> a -> a) -> Either e a -> a #

foldl1 :: (a -> a -> a) -> Either e a -> a #

toList :: Either e a -> [a] #

null :: Either e a -> Bool #

length :: Either e a -> Int #

elem :: Eq a => a -> Either e a -> Bool #

maximum :: Ord a => Either e a -> a #

minimum :: Ord a => Either e a -> a #

sum :: Num a => Either e a -> a #

product :: Num a => Either e a -> a #

Eq a => Eq1 (Either a) Source #

Instance details

Defined in Data.Strict.Either

Methods

liftEq :: (a0 -> b -> Bool) -> Either a a0 -> Either a b -> Bool #

Ord a => Ord1 (Either a) Source #

Instance details

Defined in Data.Strict.Either

Methods

liftCompare :: (a0 -> b -> Ordering) -> Either a a0 -> Either a b -> Ordering #

Read a => Read1 (Either a) Source #

Instance details

Defined in Data.Strict.Either

Methods

liftReadsPrec :: (Int -> ReadS a0) -> ReadS [a0] -> Int -> ReadS (Either a a0) #

liftReadList :: (Int -> ReadS a0) -> ReadS [a0] -> ReadS [Either a a0] #

liftReadPrec :: ReadPrec a0 -> ReadPrec [a0] -> ReadPrec (Either a a0) #

liftReadListPrec :: ReadPrec a0 -> ReadPrec [a0] -> ReadPrec [Either a a0] #

Show a => Show1 (Either a) Source #

Instance details

Defined in Data.Strict.Either

Methods

liftShowsPrec :: (Int -> a0 -> ShowS) -> ([a0] -> ShowS) -> Int -> Either a a0 -> ShowS #

liftShowList :: (Int -> a0 -> ShowS) -> ([a0] -> ShowS) -> [Either a a0] -> ShowS #

Traversable (Either e) Source #

Instance details

Defined in Data.Strict.Either

Methods

traverse :: Applicative f => (a -> f b) -> Either e a -> f (Either e b) #

sequenceA :: Applicative f => Either e (f a) -> f (Either e a) #

mapM :: Monad m => (a -> m b) -> Either e a -> m (Either e b) #

sequence :: Monad m => Either e (m a) -> m (Either e a) #

Functor (Either a) Source #

Instance details

Defined in Data.Strict.Either

Methods

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

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

NFData a => NFData1 (Either a) Source #

Instance details

Defined in Data.Strict.Either

Methods

liftRnf :: (a0 -> ()) -> Either a a0 -> () #

Hashable a => Hashable1 (Either a) Source #

Instance details

Defined in Data.Strict.Either

Methods

liftHashWithSalt :: (Int -> a0 -> Int) -> Int -> Either a a0 -> Int #

(Data a, Data b) => Data (Either a b) Source #

Instance details

Defined in Data.Strict.Either

Methods

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 :: forall r r'. (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) #

Semigroup (Either a b) Source #

Instance details

Defined in Data.Strict.Either

Methods

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

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

stimes :: Integral b0 => b0 -> Either a b -> Either a b #

Generic (Either a b) Source #

Instance details

Defined in Data.Strict.Either

Associated Types

type Rep (Either a b) :: Type -> Type #

Methods

from :: Either a b -> Rep (Either a b) x #

to :: Rep (Either a b) x -> Either a b #

(Read a, Read b) => Read (Either a b) Source #

Instance details

Defined in Data.Strict.Either

Methods

readsPrec :: Int -> ReadS (Either a b) #

readList :: ReadS [Either a b] #

readPrec :: ReadPrec (Either a b) #

readListPrec :: ReadPrec [Either a b] #

(Show a, Show b) => Show (Either a b) Source #

Instance details

Defined in Data.Strict.Either

Methods

showsPrec :: Int -> Either a b -> ShowS #

show :: Either a b -> String #

showList :: [Either a b] -> ShowS #

(Binary a, Binary b) => Binary (Either a b) Source #

Instance details

Defined in Data.Strict.Either

Methods

put :: Either a b -> Put #

get :: Get (Either a b) #

putList :: [Either a b] -> Put #

(NFData a, NFData b) => NFData (Either a b) Source #

Instance details

Defined in Data.Strict.Either

Methods

rnf :: Either a b -> () #

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

Instance details

Defined in Data.Strict.Either

Methods

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

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

(Ord a, Ord b) => Ord (Either a b) Source #

Instance details

Defined in Data.Strict.Either

Methods

compare :: Either a b -> Either a b -> Ordering #

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

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

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

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

max :: Either a b -> Either a b -> Either a b #

min :: Either a b -> Either a b -> Either a b #

(Hashable a, Hashable b) => Hashable (Either a b) Source #

Instance details

Defined in Data.Strict.Either

Methods

hashWithSalt :: Int -> Either a b -> Int #

hash :: Either a b -> Int #

Strict (Either a b) (Either a b) Source #

Instance details

Defined in Data.Strict.Classes

Methods

toStrict :: Either0 a b -> Either a b Source #

toLazy :: Either a b -> Either0 a b Source #

type Rep1 (Either a :: Type -> Type) Source #

Instance details

Defined in Data.Strict.Either

type Rep1 (Either a :: Type -> Type) = D1 ('MetaData "Either" "Data.Strict.Either" "strict-0.5-5T7sRWGrQEO6S9uwM3LoD6" 'False) (C1 ('MetaCons "Left" 'PrefixI 'False) (S1 ('MetaSel ('Nothing :: Maybe Symbol) 'NoSourceUnpackedness 'SourceStrict 'DecidedStrict) (Rec0 a)) :+: C1 ('MetaCons "Right" 'PrefixI 'False) (S1 ('MetaSel ('Nothing :: Maybe Symbol) 'NoSourceUnpackedness 'SourceStrict 'DecidedStrict) Par1))

type Rep (Either a b) Source #

Instance details

Defined in Data.Strict.Either

type Rep (Either a b) = D1 ('MetaData "Either" "Data.Strict.Either" "strict-0.5-5T7sRWGrQEO6S9uwM3LoD6" 'False) (C1 ('MetaCons "Left" 'PrefixI 'False) (S1 ('MetaSel ('Nothing :: Maybe Symbol) 'NoSourceUnpackedness 'SourceStrict 'DecidedStrict) (Rec0 a)) :+: C1 ('MetaCons "Right" 'PrefixI 'False) (S1 ('MetaSel ('Nothing :: Maybe Symbol) 'NoSourceUnpackedness 'SourceStrict 'DecidedStrict) (Rec0 b)))

either :: (a -> c) -> (b -> c) -> Either a b -> c Source #

Case analysis: if the value is Left a, apply the first function to a; if it is Right b, apply the second function to b.

isLeft :: Either a b -> Bool Source #

Yields True iff the argument is of the form Left _.

isRight :: Either a b -> Bool Source #

Yields True iff the argument is of the form Right _.

fromLeft :: Either a b -> a Source #

Extracts the element out of a Left and throws an error if the argument is a Right .

fromRight :: Either a b -> b Source #

Extracts the element out of a Right and throws an error if the argument is a Left .

lefts :: [Either a b] -> [a] Source #

Analogous to lefts in Data.Either.

rights :: [Either a b] -> [b] Source #

Analogous to rights in Data.Either.

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

Analogous to partitionEithers in Data.Either.