kan-extensions-5.2.5: Kan extensions, Kan lifts, the Yoneda lemma, and (co)density (co)monads
Copyright 2013-2016 Edward Kmett and Dan Doel
License BSD
Maintainer Edward Kmett <ekmett@gmail.com>
Stability experimental
Portability rank N types
Safe Haskell Safe-Inferred
Language Haskell2010

Data.Functor.Day.Curried

Description

Day f -| Curried f

Day f ~ Compose f when f preserves colimits / is a left adjoint. (Due in part to the strength of all functors in Hask.)

So by the uniqueness of adjoints, when f is a left adjoint, Curried f ~ Rift f

Synopsis

Right Kan lifts

newtype Curried g h a Source #

Constructors

Curried

Fields

Instances

Instances details
Functor g => Functor ( Curried g h) Source #
Instance details

Defined in Data.Functor.Day.Curried

Methods

fmap :: (a -> b) -> Curried g h a -> Curried g h b Source #

(<$) :: a -> Curried g h b -> Curried g h a Source #

( Functor g, g ~ h) => Applicative ( Curried g h) Source #
Instance details

Defined in Data.Functor.Day.Curried

toCurried :: ( forall x. Day g k x -> h x) -> k a -> Curried g h a Source #

The universal property of Curried

fromCurried :: Functor f => ( forall a. k a -> Curried f h a) -> Day f k b -> h b Source #

applied :: Functor f => Day f ( Curried f g) a -> g a Source #

This is the counit of the Day f -| Curried f adjunction

unapplied :: g a -> Curried f ( Day f g) a Source #

This is the unit of the Day f -| Curried f adjunction

adjointToCurried :: Adjunction f u => u a -> Curried f Identity a Source #

Curried f Identity a is isomorphic to the right adjoint to f if one exists.

adjointToCurried . curriedToAdjointid
curriedToAdjoint . adjointToCurriedid

curriedToAdjoint :: Adjunction f u => Curried f Identity a -> u a Source #

Curried f Identity a is isomorphic to the right adjoint to f if one exists.

composedAdjointToCurried :: ( Functor h, Adjunction f u) => u (h a) -> Curried f h a Source #

Curried f h a is isomorphic to the post-composition of the right adjoint of f onto h if such a right adjoint exists.

curriedToComposedAdjoint :: Adjunction f u => Curried f h a -> u (h a) Source #

Curried f h a is isomorphic to the post-composition of the right adjoint of f onto h if such a right adjoint exists.

curriedToComposedAdjoint . composedAdjointToCurriedid
composedAdjointToCurried . curriedToComposedAdjointid

liftCurried :: Applicative f => f a -> Curried f f a Source #

The natural isomorphism between f and Curried f f . lowerCurried . liftCurried id liftCurried . lowerCurried id

lowerCurried (liftCurried x)     -- definition
lowerCurried (Curried (<*> x))   -- definition
(<*> x) (pure id)          -- beta reduction
pure id <*> x              -- Applicative identity law
x

lowerCurried :: Applicative f => Curried f g a -> g a Source #

Lower Curried by applying pure id to the continuation.

See liftCurried .

rap :: Functor f => Curried f g (a -> b) -> Curried g h a -> Curried f h b Source #

Indexed applicative composition of right Kan lifts.