[GHC] #7804: Ambiguity check too eager in presence of RankNTypes and TypeFamilies

[GHC]

#7804: Ambiguity check too eager in presence of RankNTypes and TypeFamilies
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  Reporter:  goldfire                            |          Owner:                  
      Type:  bug                                 |         Status:  closed          
  Priority:  normal                              |      Milestone:                  
 Component:  Compiler                            |        Version:  7.7             
Resolution:  fixed                               |       Keywords:  AmbiguityCheck  
        Os:  Unknown/Multiple                    |   Architecture:  Unknown/Multiple
   Failure:  GHC rejects valid program           |     Difficulty:  Unknown         
  Testcase:  indexed-types/should_compile/T7804  |      Blockedby:                  
  Blocking:                                      |        Related:                  
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Changes (by simonpj):

  * status:  new => closed
  * difficulty:  => Unknown
  * resolution:  => fixed
  * testcase:  => indexed-types/should_compile/T7804


Comment:

 Quite right!  This was trickier than I thought and, as the comment says,
 I'm still not happy.  But this program should be fine, and it is now.

 Simon

-- 
Ticket URL: <http://hackage.haskell.org/trac/ghc/ticket/7804#comment:2>
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