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{-# LANGUAGE ImpredicativeTypes #-}
-- Tests SPECIAL CASE 2 in GHC.Tc.Gen.Bind.tcMonoBinds
-- See Note [Special case for non-recursive pattern bindings]
--
-- Doesn't have any useful effect until we have
-- ImpredicativeTypes, but does no harm either
module T18323 where
ids :: [forall a. a -> a]
ids = [id]
combine :: (forall a . [a] -> a)
-> [forall a. a -> a]
-> ((forall a . [a] -> a), [forall a. a -> a])
combine x y = (x,y)
-- This works
works = let t = combine head ids
in (fst t) (snd t) True
-- But this does not typecheck, and it could
breaks = let (x,y) = combine head ids
in x y True
-- And nor does this, but it could too
breaks2 = let (t) = combine head ids
in (fst t) (snd t) True
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