[GHC] #11621: GHC doesn't see () as a Constraint in type family

[GHC]

#11621: GHC doesn't see () as a Constraint in type family
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        Reporter:  Iceland_jack      |                Owner:  (none)
            Type:  bug               |               Status:  new
        Priority:  normal            |            Milestone:
       Component:  Compiler (Type    |              Version:  7.10.1
  checker)                           |             Keywords:
      Resolution:                    |  ConstraintKinds
Operating System:  Unknown/Multiple  |         Architecture:
                                     |  Unknown/Multiple
 Type of failure:  None/Unknown      |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:  #11715            |  Differential Rev(s):
       Wiki Page:                    |
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Changes (by simonpj):

 * keywords:   => ConstraintKinds


Comment:

 See also #13742

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Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/11621#comment:5>
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