[GHC] #11450: Associated types at wrong type in instance

[GHC]

#11450: Associated types at wrong type in instance
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        Reporter:  simonpj           |                Owner:
            Type:  bug               |               Status:  new
        Priority:  high              |            Milestone:  8.0.1
       Component:  Compiler          |              Version:  7.10.3
      Resolution:                    |             Keywords:
Operating System:  Unknown/Multiple  |         Architecture:
                                     |  Unknown/Multiple
 Type of failure:  None/Unknown      |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:                    |  Differential Rev(s):
       Wiki Page:                    |
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Comment (by simonpj):

 Yes to comment:11.  I still say that the args to the type family should be
 identical to in the icnstance header, in the positions that are linked by
 the class decl.  No wildcards.

 As to comment:13, yes that's right.  We do allow that generality.  (But we
 don't in the default decl of an associated type, in a class decl; I was
 confused.)

 Summary of long thread: the Description of this ticket is still right!

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Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/11450#comment:15>
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