{-# LANGUAGE TypeFamilies #-}
module Data.Lens.Edit.Stateful where

import Data.Lens.Bidirectional

class Bidirectional l => Lens l where
	type C l
	missing :: l -> C l
	dputr   :: l -> (L l, C l) -> (R l, C l)
	dputl   :: l -> (R l, C l) -> (L l, C l)