[GHC] #5600: Instantiation of a rank 2 type fails for type synonyms

[GHC]

#5600: Instantiation of a rank 2 type fails for type synonyms
---------------------------------+------------------------------------------
    Reporter:  paba              |       Owner:                         
        Type:  bug               |      Status:  new                    
    Priority:  normal            |   Component:  Compiler (Type checker)
     Version:  7.2.1             |    Keywords:                         
    Testcase:                    |   Blockedby:                         
          Os:  Unknown/Multiple  |    Blocking:                         
Architecture:  Unknown/Multiple  |     Failure:  None/Unknown           
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Comment(by kosmikus):

 AFAICS, GHC is correct to reject this program. You are trying to pass a
 function of type
 {{{
 forall a. F () -> b
 }}}
 in a position where
 {{{
 forall a. g a -> b
 }}}
 is expected.

-- 
Ticket URL: <http://hackage.haskell.org/trac/ghc/ticket/5600#comment:2>
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