[GHC] #15793: Type family doesn't reduce with visible kind application

[GHC]

#15793: Type family doesn't reduce with visible kind application
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        Reporter:  Iceland_jack      |                Owner:  (none)
            Type:  bug               |               Status:  closed
        Priority:  normal            |            Milestone:
       Component:  Compiler          |              Version:  8.6.1
      Resolution:  invalid           |             Keywords:
                                     |  TypeApplications
Operating System:  Unknown/Multiple  |         Architecture:
                                     |  Unknown/Multiple
 Type of failure:  None/Unknown      |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:                    |  Differential Rev(s):
       Wiki Page:                    |
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Changes (by goldfire):

 * status:  new => closed
 * resolution:   => invalid


Comment:

 This is expected behavior. Your `F2` has an arity of 0 and so takes no
 argument, visible or otherwise. See related discussion in #11719.

 We don't yet have the syntax to declare a type family whose argument is
 both invisible and non-dependent. This would work fine internally, but
 there's just no way to say it.

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/15793#comment:1>
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