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{-# LANGUAGE MultiParamTypeClasses, FunctionalDependencies,
ExistentialQuantification, Rank2Types,
FlexibleInstances #-}
-- Arguably, the type signature for f1 should be enough to make
-- this program compile, but in 5.04 it wasn't; the
-- extra sig in f2 was needed.
--
-- This is a pretty borderline case.
module ShouldCompile where
class C t a b | t a -> b
instance C Char a Bool
data P t a = forall b. (C t a b) => MkP b
data Q t = MkQ (forall a. P t a)
f1 :: Q Char
f1 = MkQ (MkP True)
f2 :: Q Char
f2 = MkQ (MkP True :: forall a. P Char a)
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