[GHC] #13913: Can't apply higher-ranked kind in type family

[GHC]

#13913: Can't apply higher-ranked kind in type family
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        Reporter:  RyanGlScott       |                Owner:  (none)
            Type:  bug               |               Status:  new
        Priority:  normal            |            Milestone:
       Component:  Compiler (Type    |              Version:  8.0.1
  checker)                           |
      Resolution:                    |             Keywords:
Operating System:  Unknown/Multiple  |         Architecture:
 Type of failure:  GHC rejects       |  Unknown/Multiple
  valid program                      |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:                    |  Differential Rev(s):
       Wiki Page:                    |
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Comment (by goldfire):

 I believe this is a dup of #11719. My recent [https://github.com/ghc-
 proposals/ghc-proposals/pull/55 proposal] around adding explicit `forall`s
 to type family equations will introduce a workaround. Perhaps a simple
 case like this, though, could be made to work.

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Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/13913#comment:1>
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