Copyright | (C) 2013-2015 Edward Kmett and Dan Doel |
---|---|
License | BSD-style (see the file LICENSE) |
Maintainer | Edward Kmett <ekmett@gmail.com> |
Stability | provisional |
Portability | Rank2Types, TFs |
Safe Haskell | Safe |
Language | Haskell2010 |
Synopsis
- newtype Ran p q a b = Ran {
- runRan :: forall x. p x a -> q x b
- decomposeRan :: Procompose (Ran q p) q :-> p
- 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
- newtype Codensity p a b = Codensity {
- runCodensity :: forall x. p x a -> p x b
- decomposeCodensity :: Procompose (Codensity p) p a b -> p a b
Documentation
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.
Instances
Category p => ProfunctorComonad (Ran p) Source # | |
Defined in Data.Profunctor.Ran proextract :: Profunctor p0 => Ran p p0 :-> p0 Source # produplicate :: Profunctor p0 => Ran p p0 :-> Ran p (Ran p p0) Source # | |
ProfunctorFunctor (Ran p) Source # | |
Defined in Data.Profunctor.Ran | |
p ~ q => Category (Ran p q :: * -> * -> *) Source # |
|
(Profunctor p, Profunctor q) => Profunctor (Ran p q) Source # | |
Defined in Data.Profunctor.Ran dimap :: (a -> b) -> (c -> d) -> Ran p q b c -> Ran p q a d Source # lmap :: (a -> b) -> Ran p q b c -> Ran p q a c Source # rmap :: (b -> c) -> Ran p q a b -> Ran p q a c Source # (#.) :: Coercible c b => q0 b c -> Ran p q a b -> Ran p q a c Source # (.#) :: Coercible b a => Ran p q b c -> q0 a b -> Ran p q a c Source # | |
Profunctor q => Functor (Ran p q a) Source # | |
decomposeRan :: Procompose (Ran q p) q :-> p Source #
The 2-morphism that defines a right Kan extension.
Note: When q
is left adjoint to
then Ran
q (->)decomposeRan
is the counit
of the adjunction.
precomposeRan :: Profunctor q => Procompose q (Ran p (->)) :-> Ran p q Source #
uncurryRan :: (p :-> Ran q r) -> Procompose p q :-> r Source #
newtype Codensity p a b Source #
This represents the right Kan extension of a Profunctor
p
along itself. This provides a generalization of the "difference list" trick to profunctors.
Codensity | |
|
Instances
Profunctor p => Profunctor (Codensity p) Source # | |
Defined in Data.Profunctor.Ran dimap :: (a -> b) -> (c -> d) -> Codensity p b c -> Codensity p a d Source # lmap :: (a -> b) -> Codensity p b c -> Codensity p a c Source # rmap :: (b -> c) -> Codensity p a b -> Codensity p a c Source # (#.) :: Coercible c b => q b c -> Codensity p a b -> Codensity p a c Source # (.#) :: Coercible b a => Codensity p b c -> q a b -> Codensity p a c Source # | |
Category (Codensity p :: * -> * -> *) Source # | |
Profunctor p => Functor (Codensity p a) Source # | |
decomposeCodensity :: Procompose (Codensity p) p a b -> p a b Source #