lenz-mtl-0.1: mtl operations with Van Laarhoven lenses
Control.Monad.Reader.Lens
asks :: MonadReader α m => ((a -> Const a b) -> α -> Const a β) -> m a Source #
local :: MonadReader α m => Lens α α a b -> (a -> b) -> m c -> m c Source #
localM :: MonadReader α m => Lens α α a b -> (a -> m b) -> m c -> m c Source #