Copyright	(C) 2011-2016 Edward Kmett
License	BSD-style (see the file LICENSE)
Maintainer	Edward Kmett <ekmett@gmail.com>
Stability	provisional
Portability	portable
Safe Haskell	Trustworthy
Language	Haskell2010

Data.Distributive.Generic

Description

Synopsis

class GDistributive g where
- gcollect :: Functor f => (a -> g b) -> f a -> g (f b)
genericCollect :: (Functor f, Generic1 g, GDistributive (Rep1 g)) => (a -> g b) -> f a -> g (f b)
genericDistribute :: (Functor f, Generic1 g, GDistributive (Rep1 g)) => f (g a) -> g (f a)

Documentation

class GDistributive g where #

Methods

gcollect :: Functor f => (a -> g b) -> f a -> g (f b) #

Instances details

GDistributive Par1 #
Instance details Defined in Data.Distributive.Generic Methods gcollect :: Functor f => (a -> Par1 b) -> f a -> Par1 (f b) #
GDistributive (U1 :: Type -> Type) #
Instance details Defined in Data.Distributive.Generic Methods gcollect :: Functor f => (a -> U1 b) -> f a -> U1 (f b) #
Distributive f => GDistributive (Rec1 f) #
Instance details Defined in Data.Distributive.Generic Methods gcollect :: Functor f0 => (a -> Rec1 f b) -> f0 a -> Rec1 f (f0 b) #
(GDistributive a, GDistributive b) => GDistributive (a :*: b) #
Instance details Defined in Data.Distributive.Generic Methods gcollect :: Functor f => (a0 -> (a :: b) b0) -> f a0 -> (a :: b) (f b0) #
GDistributive f => GDistributive (M1 i c f) #
Instance details Defined in Data.Distributive.Generic Methods gcollect :: Functor f0 => (a -> M1 i c f b) -> f0 a -> M1 i c f (f0 b) #
(Distributive a, GDistributive b) => GDistributive (a :.: b) #
Instance details Defined in Data.Distributive.Generic Methods gcollect :: Functor f => (a0 -> (a :.: b) b0) -> f a0 -> (a :.: b) (f b0) #

genericCollect :: (Functor f, Generic1 g, GDistributive (Rep1 g)) => (a -> g b) -> f a -> g (f b) #

collect derived from a Generic1 type

This can be used to easily produce a Distributive instance for a type with a Generic1 instance,

data V2 a = V2 a a deriving (Show, Functor, Generic1)
instance Distributive V2' where collect = genericCollect

distribute derived from a Generic1 type

It's often more efficient to use genericCollect instead.