compdata-0.13.1: Compositional Data Types
Copyright(c) 2014 Patrick Bahr
LicenseBSD3
MaintainerPatrick Bahr <paba@di.ku.dk>
Stabilityexperimental
Portabilitynon-portable (GHC Extensions)
Safe HaskellSafe-Inferred
LanguageHaskell2010

Data.Comp.Multi.Projection

Description

This module provides a generic projection function pr for arbitrary nested binary products.

Synopsis
  • pr :: forall p q a. p :< q => q a -> p a
  • type (:<) f g = Proj (ComprEmb (Elem f g)) f g
  • data (f :*: g) a = (f a) :*: (g a)
  • ffst :: (f :*: g) a -> f a
  • fsnd :: (f :*: g) a -> g a

Documentation

pr :: forall p q a. p :< q => q a -> p a Source #

This function projects the component of type e out or the compound value of type p.

type (:<) f g = Proj (ComprEmb (Elem f g)) f g infixl 5 Source #

The constraint e :< p expresses that e is a component of the type p. That is, p is formed by binary products using the type e. The occurrence of e must be unique. For example we have Int :< (Bool,(Int,Bool)) but not Bool :< (Bool,(Int,Bool)).

data (f :*: g) a infixr 8 Source #

Formal product of signatures (functors).

Constructors

(f a) :*: (g a) infixr 8 

Instances

Instances details
(Foldable f, Foldable g) => Foldable (f :*: g) Source # 
Instance details

Defined in Data.Comp.Ops

Methods

fold :: Monoid m => (f :*: g) m -> m #

foldMap :: Monoid m => (a -> m) -> (f :*: g) a -> m #

foldMap' :: Monoid m => (a -> m) -> (f :*: g) a -> m #

foldr :: (a -> b -> b) -> b -> (f :*: g) a -> b #

foldr' :: (a -> b -> b) -> b -> (f :*: g) a -> b #

foldl :: (b -> a -> b) -> b -> (f :*: g) a -> b #

foldl' :: (b -> a -> b) -> b -> (f :*: g) a -> b #

foldr1 :: (a -> a -> a) -> (f :*: g) a -> a #

foldl1 :: (a -> a -> a) -> (f :*: g) a -> a #

toList :: (f :*: g) a -> [a] #

null :: (f :*: g) a -> Bool #

length :: (f :*: g) a -> Int #

elem :: Eq a => a -> (f :*: g) a -> Bool #

maximum :: Ord a => (f :*: g) a -> a #

minimum :: Ord a => (f :*: g) a -> a #

sum :: Num a => (f :*: g) a -> a #

product :: Num a => (f :*: g) a -> a #

(Traversable f, Traversable g) => Traversable (f :*: g) Source # 
Instance details

Defined in Data.Comp.Ops

Methods

traverse :: Applicative f0 => (a -> f0 b) -> (f :*: g) a -> f0 ((f :*: g) b) #

sequenceA :: Applicative f0 => (f :*: g) (f0 a) -> f0 ((f :*: g) a) #

mapM :: Monad m => (a -> m b) -> (f :*: g) a -> m ((f :*: g) b) #

sequence :: Monad m => (f :*: g) (m a) -> m ((f :*: g) a) #

(Functor f, Functor g) => Functor (f :*: g) Source # 
Instance details

Defined in Data.Comp.Ops

Methods

fmap :: (a -> b) -> (f :*: g) a -> (f :*: g) b #

(<$) :: a -> (f :*: g) b -> (f :*: g) a #

ffst :: (f :*: g) a -> f a Source #

fsnd :: (f :*: g) a -> g a Source #