Data.Generics.Internal.Lens

Internal lens helpers. Only exported for Haddock

Documentation

type Lens' s a = forall f. Functor f => (a -> f a) -> s -> f s

Type alias for lens

type Prism' s a = forall p f. (Choice p, Applicative f) => p a (f a) -> p s (f s)

Type alias for prism

type Iso' s a = forall p f. (Profunctor p, Functor f) => p a (f a) -> p s (f s)

(^.) :: s -> ((a -> Const a a) -> s -> Const a s) -> a infixl 8

Getting

set :: ((a -> Identity b) -> s -> Identity t) -> b -> s -> t

Setting

first :: Lens' ((a :*: b) x) (a x)

Lens focusing on the first element of a product

second :: Lens' ((a :*: b) x) (b x)

Lens focusing on the second element of a product

left :: Prism' ((a :+: b) x) (a x)

right :: Prism' ((a :+: b) x) (b x)

combine :: Lens' (s x) a -> Lens' (t x) a -> Lens' ((s :+: t) x) a

prism :: (a -> s) -> (s -> Either s a) -> Prism' s a

repIso :: Generic a => Iso' a (Rep a x)

A type and its generic representation are isomorphic

mIso :: Iso' (M1 i c f p) (f p)

M1 is just a wrapper around `f p`

mLens :: Lens' (M1 i c f p) (f p)

repLens :: Generic a => Lens' a (Rep a x)

sumIso :: Iso' ((a :+: b) x) (Either (a x) (b x))

_Left :: Prism' (Either a c) a

_Right :: Prism' (Either c a) a

data Coyoneda f b

Constructors

Coyoneda (a -> b) (f a)

Instances

Functor (Coyoneda f)

Methods

fmap :: (a -> b) -> Coyoneda f a -> Coyoneda f b

(<$) :: a -> Coyoneda f b -> Coyoneda f a

inj :: Functor f => Coyoneda f a -> f a

proj :: Functor f => f a -> Coyoneda f a

ravel :: Functor f => ((a -> Coyoneda f b) -> s -> Coyoneda f t) -> (a -> f b) -> s -> f t