Copyright	(C) 2012 Edward Kmett
License	BSD-style (see the file LICENSE)
Maintainer	Edward Kmett <ekmett@gmail.com>
Stability	provisional
Portability	GADTs, Rank2Types
Safe Haskell	Safe
Language	Haskell2010

Control.Alternative.Free

Description

Left distributive Alternative functors for free, based on a design by Stijn van Drongelen.

Synopsis

newtype Alt f a = Alt {
- alternatives :: [ AltF f a]
}
data AltF f a where
- Ap :: f a -> Alt f (a -> b) -> AltF f b
- Pure :: a -> AltF f a
runAlt :: forall f g a. Alternative g => ( forall x. f x -> g x) -> Alt f a -> g a
liftAlt :: f a -> Alt f a
hoistAlt :: ( forall a. f a -> g a) -> Alt f b -> Alt g b

Documentation

newtype Alt f a Source #

Constructors

Alt
Fields alternatives :: [ AltF f a]

Instances

Instances details

Functor ( Alt f) Source #
Instance details Defined in Control.Alternative.Free Methods fmap :: (a -> b) -> Alt f a -> Alt f b Source # (<$) :: a -> Alt f b -> Alt f a Source #
Applicative ( Alt f) Source #
Instance details Defined in Control.Alternative.Free Methods pure :: a -> Alt f a Source # (<>) :: Alt f (a -> b) -> Alt f a -> Alt f b Source # liftA2 :: (a -> b -> c) -> Alt f a -> Alt f b -> Alt f c Source # (>) :: Alt f a -> Alt f b -> Alt f b Source # (<*) :: Alt f a -> Alt f b -> Alt f a Source #
Alternative ( Alt f) Source #
Instance details Defined in Control.Alternative.Free Methods empty :: Alt f a Source # (<\|>) :: Alt f a -> Alt f a -> Alt f a Source # some :: Alt f a -> Alt f [a] Source # many :: Alt f a -> Alt f [a] Source #
Alt ( Alt f) Source #
Instance details Defined in Control.Alternative.Free Methods (<!>) :: Alt f a -> Alt f a -> Alt f a Source # some :: Applicative ( Alt f) => Alt f a -> Alt f [a] Source # many :: Applicative ( Alt f) => Alt f a -> Alt f [a] Source #
Apply ( Alt f) Source #
Instance details Defined in Control.Alternative.Free Methods (<.>) :: Alt f (a -> b) -> Alt f a -> Alt f b Source # (.>) :: Alt f a -> Alt f b -> Alt f b Source # (<.) :: Alt f a -> Alt f b -> Alt f a Source # liftF2 :: (a -> b -> c) -> Alt f a -> Alt f b -> Alt f c Source #
Semigroup ( Alt f a) Source #
Instance details Defined in Control.Alternative.Free Methods (<>) :: Alt f a -> Alt f a -> Alt f a Source # sconcat :: NonEmpty ( Alt f a) -> Alt f a Source # stimes :: Integral b => b -> Alt f a -> Alt f a Source #
Monoid ( Alt f a) Source #
Instance details Defined in Control.Alternative.Free Methods mempty :: Alt f a Source # mappend :: Alt f a -> Alt f a -> Alt f a Source # mconcat :: [ Alt f a] -> Alt f a Source #

data AltF f a where Source #

Constructors

Ap :: f a -> Alt f (a -> b) -> AltF f b infixl 3
Pure :: a -> AltF f a

Instances

Instances details

Functor ( AltF f) Source #
Instance details Defined in Control.Alternative.Free Methods fmap :: (a -> b) -> AltF f a -> AltF f b Source # (<$) :: a -> AltF f b -> AltF f a Source #
Applicative ( AltF f) Source #
Instance details Defined in Control.Alternative.Free Methods pure :: a -> AltF f a Source # (<>) :: AltF f (a -> b) -> AltF f a -> AltF f b Source # liftA2 :: (a -> b -> c) -> AltF f a -> AltF f b -> AltF f c Source # (>) :: AltF f a -> AltF f b -> AltF f b Source # (<*) :: AltF f a -> AltF f b -> AltF f a Source #

runAlt :: forall f g a. Alternative g => ( forall x. f x -> g x) -> Alt f a -> g a Source #

Given a natural transformation from f to g , this gives a canonical monoidal natural transformation from Alt f to g .

liftAlt :: f a -> Alt f a Source #

A version of lift that can be used with any f .

hoistAlt :: ( forall a. f a -> g a) -> Alt f b -> Alt g b Source #

Given a natural transformation from f to g this gives a monoidal natural transformation from Alt f to Alt g .