Data.Strict.Either

Strict Either.

Same as the standard Haskell Either, but Left _|_ = Right _|_ = _|_

Documentation

data Either a b

The strict choice type.

Constructors

Left !a

Right !b

Instances

Bifunctor 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

Functor (Either a)

Methods

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

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

Foldable (Either a)

Methods

fold :: Monoid m => Either a m -> m

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

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

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

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

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

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

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

toList :: Either a a -> [a]

null :: Either a a -> Bool

length :: Either a a -> Int

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

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

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

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

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

Traversable (Either a)

Methods

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

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

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

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

Generic1 (Either a)

Associated Types

type Rep1 (Either a :: * -> *) :: * -> *

Methods

from1 :: Either a a -> Rep1 (Either a) a

to1 :: Rep1 (Either a) a -> Either a a

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

Methods

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

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

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

Methods

gfoldl :: (forall d c. Data d => c (d -> c) -> d -> c c) -> (forall g. g -> c g) -> Either a b -> c (Either a b)

gunfold :: (forall c r. Data c => c (c -> 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 c. Data c => c -> c) -> 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 b, Ord a) => Ord (Either a b)

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

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

Methods

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

readList :: ReadS [Either a b]

readPrec :: ReadPrec (Either a b)

readListPrec :: ReadPrec [Either a b]

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

Methods

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

show :: Either a b -> String

showList :: [Either a b] -> ShowS

Generic (Either a b)

Associated Types

type Rep (Either a b) :: * -> *

Methods

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

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

type Rep1 (Either a)

type Rep1 (Either a) = D1 (MetaData "Either" "Data.Strict.Either" "strict-base-0.4.0.0-1k3wDu59CS22iu6yIZo2Dn" False) ((:+:) (C1 (MetaCons "Left" PrefixI False) (S1 (MetaSel (Nothing Symbol) NoSourceUnpackedness SourceStrict DecidedStrict) (Rec0 a))) (C1 (MetaCons "Right" PrefixI False) (S1 (MetaSel (Nothing Symbol) NoSourceUnpackedness SourceStrict DecidedStrict) Par1)))

type Rep (Either a b)

type Rep (Either a b) = D1 (MetaData "Either" "Data.Strict.Either" "strict-base-0.4.0.0-1k3wDu59CS22iu6yIZo2Dn" False) ((:+:) (C1 (MetaCons "Left" PrefixI False) (S1 (MetaSel (Nothing Symbol) NoSourceUnpackedness SourceStrict DecidedStrict) (Rec0 a))) (C1 (MetaCons "Right" PrefixI False) (S1 (MetaSel (Nothing Symbol) NoSourceUnpackedness SourceStrict DecidedStrict) (Rec0 b))))

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

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

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

isRight :: Either a b -> Bool

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

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

Analogous to lefts in Data.Either.

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

Analogous to rights in Data.Either.

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

Analogous to partitionEithers in Data.Either.

Orphan instances

IsStrict (Either a b) (Either a b)

Methods

fromStrict :: Either a b -> Either a b

toStrict :: Either a b -> Either a b