[GHC] #15810: Kind inference error in classes

[GHC]

#15810: Kind inference error in classes
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        Reporter:  goldfire          |                Owner:  (none)
            Type:  bug               |               Status:  new
        Priority:  normal            |            Milestone:
       Component:  Compiler          |              Version:  8.6.1
      Resolution:                    |             Keywords:
Operating System:  Unknown/Multiple  |         Architecture:
                                     |  Unknown/Multiple
 Type of failure:  None/Unknown      |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:                    |  Differential Rev(s):  Phab:D5305
       Wiki Page:                    |
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Comment (by goldfire):

 Did you mean for the last example in comment:4 to be different than the
 first? I presume you did.

 We allow

 {{{#!hs
 data T a where
   MkT :: T (a :: k)
 }}}

 today. That `k` is also locally quantified.

 I can see the argument for rejecting the original program, but it's
 inconsistent to reject that while accepting the datatype equivalent.

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/15810#comment:5>
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