#7347: Existential data constructors should not be promoted
    Reporter:  simonpj           |       Owner:                  
        Type:  bug               |      Status:  new             
    Priority:  normal            |   Milestone:                  
   Component:  Compiler          |     Version:  7.6.1           
    Keywords:                    |          Os:  Unknown/Multiple
Architecture:  Unknown/Multiple  |     Failure:  None/Unknown    
  Difficulty:  Unknown           |    Testcase:                  
   Blockedby:                    |    Blocking:                  
     Related:                    |  

Comment(by kosmikus):

 I'm sorry. I was confused by the fact that if I load a file containing
 data Ex = forall a. MkEx a
 into GHCi, I get this:
 *Main> :kind 'MkEx
 'MkEx :: * -> Ex
 But I note now that this is because I didn't say `PolyKinds` in GHCi.
 Indeed, then I get:
 *Main> :set -XPolyKinds
 *Main> :kind 'MkEx
 'MkEx :: k -> Ex
 So I thought GHC would not promote to an existential quantification on the
 type level, but it actually does. So yes, I was wrong, and this is indeed

Ticket URL: <http://hackage.haskell.org/trac/ghc/ticket/7347#comment:7>
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