[GHC] #13538: Weird kind inference problems with closed type families

[GHC]

#13538: Weird kind inference problems with closed type families
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        Reporter:  achirkin          |                Owner:  (none)
            Type:  bug               |               Status:  new
        Priority:  normal            |            Milestone:
       Component:  Compiler (Type    |              Version:  8.0.2
  checker)                           |
      Resolution:                    |             Keywords:
Operating System:  Unknown/Multiple  |         Architecture:
 Type of failure:  Incorrect         |  Unknown/Multiple
  error/warning at compile-time      |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:                    |  Differential Rev(s):
       Wiki Page:                    |
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Comment (by RyanGlScott):

 Interestingly, your program typechecks in GHC 8.2.1 and HEAD. I don't know
 what commit fixed it, though.

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Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/13538#comment:1>
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