[GHC] #5591: Type constructor variables not injective

[GHC]

#5591: Type constructor variables not injective
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  Reporter:  daniel.is.fischer                           |          Owner:  simonpj         
      Type:  bug                                         |         Status:  closed          
  Priority:  normal                                      |      Milestone:  7.6.2           
 Component:  Compiler (Type checker)                     |        Version:  7.2.1           
Resolution:  fixed                                       |       Keywords:                  
        Os:  Unknown/Multiple                            |   Architecture:  Unknown/Multiple
   Failure:  None/Unknown                                |     Difficulty:  Unknown         
  Testcase:  indexed-ypes/should_compile/T5591a, T5591b  |      Blockedby:                  
  Blocking:                                              |        Related:                  
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Changes (by morabbin):

 * cc: andy.adamsmoran@… (added)


Comment:

 Is this related to #6018? Brent's
 [http://stackoverflow.com/questions/7866375/why-does-ghc-think-that-this-
 type-variable-is-not-injective/ stack overflow] comment seems to imply it
 is.

-- 
Ticket URL: <http://hackage.haskell.org/trac/ghc/ticket/5591#comment:9>
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