{-# LANGUAGE CPP #-} {-# LANGUAGE ScopedTypeVariables #-} {-# LANGUAGE TemplateHaskell #-} {-# LANGUAGE TypeOperators #-} #if MIN_VERSION_template_haskell(2,12,0) {-# LANGUAGE InstanceSigs #-} {-# LANGUAGE TypeApplications #-} #endif {-| Module: GH27Spec Copyright: (C) 2019 Ryan Scott License: BSD-style (see the file LICENSE) Maintainer: Ryan Scott Portability: Template Haskell A regression test for https://github.com/haskell-compat/deriving-compat/issues/27. -} module GH27Spec where import Prelude () import Prelude.Compat import Test.Hspec #if MIN_VERSION_template_haskell(2,12,0) import Data.Deriving.Via import Data.Functor.Const newtype Age = MkAge Int $(deriveVia [t| forall a. Show Age `Via` Const Int a |]) #endif main :: IO () main = hspec spec spec :: Spec spec = pure ()