[GHC] #2037: Inner type declaration causes GHC panic

[GHC]

#2037: Inner type declaration causes GHC panic
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    Reporter:  basvandijk  |       Owner:                         
        Type:  bug         |      Status:  new                    
    Priority:  normal      |   Component:  Compiler (Type checker)
     Version:  6.8.2       |    Severity:  blocker                
    Keywords:              |    Testcase:                         
Architecture:  x86         |          Os:  Linux                  
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 I get a GHC panic when compiling the attached module.

 Sorry for the big module but I wasn't able to isolate this to a single
 simple function.

 If I comment the ''inner'' type of 'unify' on line 112 the module compiles
 just fine. So it probably has to do with
 [http://www.haskell.org/ghc/docs/latest/html/users_guide/other-type-
 extensions.html#scoped-type-variables lexically-scoped type variables].

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Ticket URL: <http://hackage.haskell.org/trac/ghc/ticket/2037>
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