Data.Generics.Internal.Lens

Internal lens helpers. Only exported for Haddock

Documentation

newtype Identity a

Identity functor

Constructors

Identity

Fields

• runIdentity :: a

Instances

Functor Identity

Functor instance

Methods

fmap :: (a -> b) -> Identity a -> Identity b

(<$) :: a -> Identity b -> Identity a

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

Type alias for lens

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

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

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

A type and its generic representation are isomorphic

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

M1 is just a wrapper around `f p`