[GHC] #7938: Unbound kind variable can appear in RHS of associated type

[GHC]

#7938: Unbound kind variable can appear in RHS of associated type
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        Reporter:  goldfire          |            Owner:  goldfire
            Type:  bug               |           Status:  new
        Priority:  normal            |        Milestone:
       Component:  Compiler          |          Version:  7.7
      Resolution:                    |         Keywords:
Operating System:  Unknown/Multiple  |     Architecture:  Unknown/Multiple
 Type of failure:  GHC accepts       |       Difficulty:  Easy (less than 1
  invalid program                    |  hour)
       Test Case:                    |       Blocked By:
        Blocking:                    |  Related Tickets:
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Changes (by goldfire):

 * difficulty:   => Easy (less than 1 hour)
 * version:  7.6.3 => 7.7


Comment:

 With the changes to kind inference that came with closed type families,
 the exact code above fails to compile, as expected. However, if we change
 the declaration of `Bar` to be `type Bar a :: k`, the code still compiles.
 Looking into this now.

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/7938#comment:1>
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