{-# LANGUAGE DeriveGeneric #-} module Main where import GHC.Generics hiding (C, D) import GShow -- We should be able to generate a generic representation for these types data D a = D0 | D1 { d11 :: a, d12 :: (D a) } deriving Generic -- Example values d0 :: D Char d0 = D0 d1 = D1 (Just 'p') D0 d2 :: D (Int,Float) d2 = D1 (3,0.14) D0 -- Generic instances instance (GShow a) => GShow (D a) -- Tests main = mapM_ putStrLn [gshow d0, gshow d1, gshow d2]