Data.Profunctor.Lift

Documentation

newtype Lift p q a b

This represents the left Kan lift 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

Lift

Fields

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

Instances

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

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

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

Profunctor p => Functor (Lift p q a)

decomposeLift :: Procompose (Lift p q) p a b -> q a b

The 2-morphism that defines a left Kan lift.

Note: When p is right adjoint to Lift p (->) then decomposeLift is the counit of the adjunction.