Data.Type.Disjunction

Two type combinators for working with disjunctions: A branch combinator '(:|:)', and a choice combinator '(:+:)'.

These are analogous to '(|||)' and '(+++)' from Arrow, respectively.

Documentation

data f :|: g :: k -> * where infixr 4

Constructors

L :: !(f a) -> (f :|: g) a

R :: !(g a) -> (f :|: g) a

Instances

Bifunctor1 k k k ((:|:) k)

Traversable1 k k ((:|:) k f)

Foldable1 k k ((:|:) k f)

Functor1 k k ((:|:) k f)

(Witness p q (f a), Witness p q (g a)) => Witness p q ((:|:) k f g a)

(Read1 k f, Read1 k g) => Read1 k ((:|:) k f g)

(Show1 k f, Show1 k g) => Show1 k ((:|:) k f g)

(Ord1 k f, Ord1 k g) => Ord1 k ((:|:) k f g)

(Eq1 k f, Eq1 k g) => Eq1 k ((:|:) k f g)

(Eq (f a), Eq (g a)) => Eq ((:|:) k f g a)

(Ord (f a), Ord (g a)) => Ord ((:|:) k f g a)

(Read (f a), Read (g a)) => Read ((:|:) k f g a)

(Show (f a), Show (g a)) => Show ((:|:) k f g a)

type WitnessC p q ((:|:) k f g a) = (Witness p q (f a), Witness p q (g a))

(>|<) :: (f a -> r) -> (g a -> r) -> (f :|: g) a -> r infixr 2

data f :+: g :: Either k l -> * where infixr 4

Constructors

L' :: !(f a) -> (f :+: g) (Left a)

R' :: !(g b) -> (f :+: g) (Right b)

Instances

Bifunctor1 k k (Either k k) ((:+:) k k)

Witness p q (g b) => Witness p q ((:+:) k k f g (Right k k b))

Witness p q (f a) => Witness p q ((:+:) k k f g (Left k k a))

Traversable1 k (Either k k) ((:+:) k k f)

Foldable1 k (Either k k) ((:+:) k k f)

Functor1 k (Either k k) ((:+:) k k f)

(Read1 k f, Read1 k1 g) => Read1 (Either k k) ((:+:) k k f g)

(Show1 k f, Show1 k1 g) => Show1 (Either k k) ((:+:) k k f g)

(Ord1 k f, Ord1 k1 g) => Ord1 (Either k k) ((:+:) k k f g)

(Eq1 k f, Eq1 k1 g) => Eq1 (Either k k) ((:+:) k k f g)

Known k1 g b => Known (Either k k) ((:+:) k k f g) (Right k k b)

Known k1 f a => Known (Either k k) ((:+:) k k f g) (Left k k a)

(Eq (f (FromLeft k k1 e)), Eq (g (FromRight k1 k e))) => Eq ((:+:) k k f g e)

(Ord (f (FromLeft k k1 e)), Ord (g (FromRight k1 k e))) => Ord ((:+:) k k f g e)

(Show (f (FromLeft k k1 e)), Show (g (FromRight k1 k e))) => Show ((:+:) k k f g e)

type WitnessC p q ((:+:) k k1 f g (Right k k1 b)) = Witness p q (g b)

type WitnessC p q ((:+:) k1 k f g (Left k1 k a)) = Witness p q (f a)

type KnownC (Either k k1) ((:+:) k k1 f g) (Right k k1 b) = Known k1 g b

type KnownC (Either k1 k) ((:+:) k1 k f g) (Left k1 k a) = Known k1 f a

(>+<) :: (forall a. (e ~ Left a) => f a -> r) -> (forall b. (e ~ Right b) => g b -> r) -> (f :+: g) e -> r infixr 2