[GHC] #9082: Unexpected behavior involving closed type families and repeat occurrences of variables

[GHC]

#9082: Unexpected behavior involving closed type families and repeat occurrences
of variables
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        Reporter:  haasn                      |            Owner:
            Type:  bug                        |           Status:  new
        Priority:  normal                     |        Milestone:
       Component:  Compiler (Type checker)    |          Version:  7.8.2
      Resolution:                             |         Keywords:
Operating System:  Unknown/Multiple           |     Architecture:
 Type of failure:  GHC rejects valid program  |  Unknown/Multiple
       Test Case:                             |       Difficulty:  Unknown
        Blocking:                             |       Blocked By:
                                              |  Related Tickets:
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Comment (by haasn):

 Oh, while simplifying the example it seems I simplified too much, this bug
 goes away if you make ‘a’ and ‘b’ less ambiguous.

 I'll have to think a bit more about the un-simplified example that fails
 to work, I may close this ticket again.

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Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/9082#comment:1>
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