[GHC] #10085: Type families cause wrapper types to disappear without cause

[GHC]

#10085: Type families cause wrapper types to disappear without cause
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        Reporter:  tathougies        |                   Owner:
            Type:  bug               |                  Status:  new
        Priority:  normal            |               Milestone:
       Component:  Compiler (Type    |                 Version:  7.8.3
  checker)                           |                Keywords:
      Resolution:                    |            Architecture:
Operating System:  Unknown/Multiple  |  Unknown/Multiple
 Type of failure:  GHC rejects       |               Test Case:
  valid program                      |                Blocking:
      Blocked By:                    |  Differential Revisions:
 Related Tickets:                    |
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Comment (by glguy):

 There may be other issues here, but a significant one is that you're
 partially applying a type synonym family. This check was missing in 7.8
 but is fixed for 7.10

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Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/10085#comment:1>
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