[GHC] #11719: Cannot use higher-rank kinds with type families

[GHC]

#11719: Cannot use higher-rank kinds with type families
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        Reporter:  ocharles          |                Owner:  (none)
            Type:  bug               |               Status:  new
        Priority:  normal            |            Milestone:  8.8.1
       Component:  Compiler (Type    |              Version:  8.0.1-rc2
  checker)                           |
      Resolution:                    |             Keywords:  TypeInType
Operating System:  Unknown/Multiple  |         Architecture:
                                     |  Unknown/Multiple
 Type of failure:  GHC rejects       |            Test Case:
  valid program                      |  dependent/should_compile/T11719
      Blocked By:                    |             Blocking:
 Related Tickets:  #13913, #14268    |  Differential Rev(s):
       Wiki Page:                    |
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Comment (by goldfire):

 comment:23 is a feature request. The use of a type variable in a type
 family equation -- even on the left-hand side -- is an occurrence, not a
 binding site. Type families aren't functions! So I think it's OK as is,
 myself.

 Someday, we'll just have type-level functions, and then all of this will
 be better. :)

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/11719#comment:24>
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