Control.Compose

TypeCompose-0.0: Type composition classes & instances

Control.Compose

Portability	portable
Stability	experimental
Maintainer	conal@conal.net

Description

Various type constructor compositions and instances for them. References: [1] "Applicative Programming with Effects" http://www.soi.city.ac.uk/~ross/papers/Applicative.html

Synopsis

class Cofunctor acc where

cofmap :: (a -> b) -> acc b -> acc a

newtype Compose g f a = Comp {

unComp :: g (f a)

}

onComp :: (g (f a) -> g' (f' a')) -> Compose g f a -> Compose g' f' a'

newtype StaticArrow f (~>) a b = Static {

unStatic :: f (a ~> b)

}

newtype Flip (~>) b a = Flip (a ~> b)

newtype ArrowAp (~>) f a b = ArrowAp {

unArrowAp :: f a ~> f b

}

newtype App f a = App {

unApp :: f a

}

Documentation

class Cofunctor acc where

Source

Often useful for acceptors (consumers, sinks) of values.

Methods

cofmap :: (a -> b) -> acc b -> acc a

Source

Instances

Arrow ~> => Cofunctor (Flip ~> b)

(Cofunctor g, Functor f) => Cofunctor (Compose g f)

newtype Compose g f a

Source

Composition of type constructors: unary & unary. Called "g . f" in [1], section 5, but GHC won't parse that, nor will it parse any infix type operators in an export list. Haddock won't parse any type infixes at all.

Constructors

Comp

unComp :: g (f a)

Instances

(Functor g, Functor f) => Functor (Compose g f)

(Applicative g, Applicative f) => Applicative (Compose g f)

(Cofunctor g, Functor f) => Cofunctor (Compose g f)

(Applicative (Compose g f), Monoid a) => Monoid (Compose g f a)

onComp :: (g (f a) -> g' (f' a')) -> Compose g f a -> Compose g' f' a'

Source

Apply a function within the Comp constructor.

newtype StaticArrow f (~>) a b