Lens.hs

{-# OPTIONS_GHC -Wno-redundant-constraints #-}

module Util.Lens
  ( postfixLFields
  , makeLensesWith
  , unwrappedP
  ) where

import Control.Lens (LensRules, Wrapped(..), lensField, lensRules, makeLensesWith, mappingNamer)

-- | For datatype with "myNyan" field it will create "myNyanL" lens.
postfixLFields :: LensRules
postfixLFields = lensRules & lensField .~ mappingNamer (\s -> [s++"L"])

unwrappedP :: Wrapped a => Proxy a -> Proxy (Unwrapped a)
unwrappedP _ = Proxy