Data.Profunctor.Sieve

Documentation

class (Profunctor p, Functor f) => Sieve p f | p -> f where

A Profunctor p is a Sieve on f if it is a subprofunctor of Star f.

That is to say it is a subset of Hom(-,f=) closed under lmap and rmap.

Alternately, you can view it as a sieve in the comma category Hask/f.

Methods

sieve :: p a b -> a -> f b

Instances

Sieve (->) Identity

(Monad m, Functor m) => Sieve (Kleisli m) m

Functor f => Sieve (Star f) f

Sieve (Forget r) (Const r)

(Sieve p f, Sieve q g) => Sieve (Procompose p q) (Compose g f)

class (Profunctor p, Functor f) => Cosieve p f | p -> f where

A Profunctor p is a Cosieve on f if it is a subprofunctor of Costar f.

That is to say it is a subset of Hom(f-,=) closed under lmap and rmap.

Alternately, you can view it as a cosieve in the comma category f/Hask.

Methods

cosieve :: p a b -> f a -> b

Instances

Cosieve (->) Identity

Functor w => Cosieve (Cokleisli w) w

Functor f => Cosieve (Costar f) f

Cosieve (Tagged *) (Proxy *)

(Cosieve p f, Cosieve q g) => Cosieve (Procompose p q) (Compose f g)