profunctors-4.4.1: Profunctors

Data.Profunctor.Rep

Description

Synopsis

# Representable Profunctors

class (Functor (Rep p), Strong p) => Representable p where Source

A `Profunctor` `p` is `Representable` if there exists a `Functor` `f` such that `p d c` is isomorphic to `d -> f c`.

Associated Types

type Rep p :: * -> * Source

Methods

tabulate :: (d -> Rep p c) -> p d c Source

rep :: p d c -> d -> Rep p c Source

Instances

 Representable (->) (Monad m, Functor m) => Representable (Kleisli m) Representable (Forget r) Functor f => Representable (UpStar f) (Representable p, Representable q) => Representable (Procompose p q) The composition of two `Representable` `Profunctor`s is `Representable` by the composition of their representations.

tabulated :: (Representable p, Representable q) => Iso (d -> Rep p c) (d' -> Rep q c') (p d c) (q d' c') Source

`tabulate` and `rep` form two halves of an isomorphism.

This can be used with the combinators from the `lens` package.

``tabulated` :: `Representable` p => `Iso'` (d -> `Rep` p c) (p d c)`

firstRep :: Representable p => p a b -> p (a, c) (b, c) Source

Default definition for `first'` given that p is `Representable`.

secondRep :: Representable p => p a b -> p (c, a) (c, b) Source

Default definition for `second'` given that p is `Representable`.

# Corepresentable Profunctors

class (Functor (Corep p), Profunctor p) => Corepresentable p where Source

A `Profunctor` `p` is `Corepresentable` if there exists a `Functor` `f` such that `p d c` is isomorphic to `f d -> c`.

Associated Types

type Corep p :: * -> * Source

Methods

cotabulate :: (Corep p d -> c) -> p d c Source

corep :: p d c -> Corep p d -> c Source

Instances

 Corepresentable (->) Functor w => Corepresentable (Cokleisli w) Corepresentable (Tagged *) Functor f => Corepresentable (DownStar f) (Corepresentable p, Corepresentable q) => Corepresentable (Procompose p q)

cotabulated :: (Corepresentable p, Corepresentable q) => Iso (Corep p d -> c) (Corep q d' -> c') (p d c) (q d' c') Source

`cotabulate` and `corep` form two halves of an isomorphism.

This can be used with the combinators from the `lens` package.

``cotabulated` :: `Corep` f p => `Iso'` (f d -> c) (p d c)`