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-- July 07: I'm changing this from "should_compile" to "should_fail".
-- It would generate an instance decl like
-- insance (Show (f a), Show (g a)) => Show (Pair1 f g a)
-- and that is not Haskell 98.
--
-- See Note [Exotic derived instance contexts] in TcSimplify.
-- The rule is simple: the context of a derived instance decl must
-- contain constraints of form (C tyvar) only, just as H98.
module ShouldCompile where
newtype Pair1 f g a = Pair1 {unPair1 :: (f a, g a)}
deriving (Eq, Ord, Show)
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