Control.Lens

Documentation

type Lens α β a b = Refractor ((~) (->)) Functor α β a b

type Refractor c d α β a b = forall p f. (d f, c p) => p a (f b) -> p α (f β)

type Traversal α β a b = Refractor ((~) (->)) Applicative α β a b

lens :: (α -> a) -> (b -> α -> β) -> Lens α β a b

iso :: (α -> a) -> (b -> β) -> Lens α β a b

get :: ((a -> Const a b) -> α -> Const a β) -> α -> a

set :: ((a -> Identity b) -> α -> Identity β) -> b -> α -> β

modify :: ((a -> Identity b) -> α -> Identity β) -> (a -> b) -> α -> β

fstL :: Lens (a, c) (b, c) a b

sndL :: Lens (a, b) (a, c) b c

swapL :: Lens (a, b) (c, d) (b, a) (d, c)

unitL :: Lens α α () ()