[GHC] #14845: TypeInType, index GADT by constraint witness

[GHC]

#14845: TypeInType, index GADT by constraint witness
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        Reporter:  Iceland_jack      |                Owner:  (none)
            Type:  feature request   |               Status:  new
        Priority:  normal            |            Milestone:
       Component:  Compiler          |              Version:  8.5
      Resolution:                    |             Keywords:  TypeInType
Operating System:  Unknown/Multiple  |         Architecture:
                                     |  Unknown/Multiple
 Type of failure:  None/Unknown      |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:  #13895            |  Differential Rev(s):
       Wiki Page:                    |
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Comment (by goldfire):

 OK. Then we can just reword the error message. :)

 Note that problem isn't that it's a GADT constructor. The problem is that
 it's a constrained constructor and constraints don't promote.

 Ryan, you find it far easier than I to actually get patches sent off --
 would you mind tweaking this message? Thanks!

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/14845#comment:9>
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