[GHC] #15677: Valid hole fits and GADT type variable names

[GHC]

#15677: Valid hole fits and GADT type variable names
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        Reporter:  RyanGlScott       |                Owner:  (none)
            Type:  bug               |               Status:  new
        Priority:  normal            |            Milestone:  8.8.1
       Component:  Compiler          |              Version:  8.6.1
      Resolution:                    |             Keywords:  TypedHoles,
                                     |  GADTs
Operating System:  Unknown/Multiple  |         Architecture:
 Type of failure:  Poor/confusing    |  Unknown/Multiple
  error message                      |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:  #9091             |  Differential Rev(s):
       Wiki Page:                    |
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Comment (by Tritlo):

 Interestingly, it also works for example 1 in #9091, but not for example 2
 (possibly because a0 is made up by the type checker?). So if we fix that,
 we can at least close #9091.

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/15677#comment:4>
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