Data.Profunctor.Ran

Documentation

newtype Ran p q a b

This represents the right Kan extension of a Profunctor q along a Profunctor p in a limited version of the 2-category of Profunctors where the only object is the category Hask, 1-morphisms are profunctors composed and compose with Profunctor composition, and 2-morphisms are just natural transformations.

Constructors

Ran

Fields

runRan :: forall x. p x a -> q x b

Instances

(~) (* -> * -> *) p q => Category * (Ran p q)

Ran p p forms a Monad in the Profunctor 2-category, which is isomorphic to a Haskell Category instance.

Category * p => ProfunctorComonad (Ran p)

ProfunctorFunctor (Ran p)

(Profunctor p, Profunctor q) => Profunctor (Ran p q)

Profunctor q => Functor (Ran p q a)

decomposeRan :: Procompose (Ran q p) q :-> p

The 2-morphism that defines a right Kan extension.

Note: When q is left adjoint to Ran q (->) then decomposeRan is the counit of the adjunction.

precomposeRan :: Profunctor q => Procompose q (Ran p (->)) :-> Ran p q

curryRan :: (Procompose p q :-> r) -> p :-> Ran q r

uncurryRan :: (p :-> Ran q r) -> Procompose p q :-> r