Data.Lens.Strict

Documentation

module Data.Lens.Common

State API

access :: Monad m => Lens a b -> StateT a m b

get the value of a lens into state

(~=), (!=) :: Monad m => Lens a b -> b -> StateT a m b

set a value using a lens into state

(%=), (!%=) :: Monad m => Lens a b -> (b -> b) -> StateT a m b

infix modification a value through a lens into state

(%%=), (!%%=) :: Monad m => Lens a b -> (b -> (c, b)) -> StateT a m c

infix modification of a value through a lens into state with a supplemental response

(+=), (!*=), (*=), (!-=), (-=), (!+=) :: (Monad m, Num b) => Lens a b -> b -> StateT a m b

(//=), (!/=) :: (Monad m, Fractional b) => Lens a b -> b -> StateT a m b

(&&=), (!||=), (!&&=), (||=) :: Monad m => Lens a Bool -> Bool -> StateT a m Bool

focus :: Monad m => Lens a b -> StateT b m c -> StateT a m c