glean/util/Glean/Util/HKD.hs (17 lines of code) (raw):

{- Copyright (c) Meta Platforms, Inc. and affiliates. All rights reserved. This source code is licensed under the BSD-style license found in the LICENSE file in the root directory of this source tree. -} {-# LANGUAGE TypeFamilies #-} -- | Useful for options, parsing, see -- <http://reasonablypolymorphic.com/blog/higher-kinded-data/> module Glean.Util.HKD ( HKD, Identity ) where import Data.Functor.Identity ( Identity ) -- | Closed type family type family HKD f a where HKD Identity a = a HKD f a = f a