{-# LANGUAGE GADTs #-} -- !!! deriving for GADTs which declare Haskell98 data types. -- bug reported as http://hackage.haskell.org/trac/ghc/ticket/902 module ShouldSucceed where data Maybe1 a where { Nothing1 :: Maybe1 a ; Just1 :: a -> Maybe1 a } deriving (Eq,Ord)