[GHC] #16374: Cannot deduce constraint from itself with poly-kinded type family

[GHC]

#16374: Cannot deduce constraint from itself with poly-kinded type family
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        Reporter:  roland            |                Owner:  (none)
            Type:  bug               |               Status:  new
        Priority:  normal            |            Milestone:
       Component:  Compiler (Type    |              Version:  8.6.3
  checker)                           |             Keywords:
      Resolution:                    |  TypeErrorMessages
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 simonpj):

 * keywords:   => TypeErrorMessages


Comment:

 > It might be helpful to have GHC automatically enable -fprint-explicit-
 kinds is an ambiguous type variable occurs in a kind position, such as in
 this program.

 I totally agree.  Would anyone like to do this?

 There are a number of other [wiki:Status/TypeErrorMessages tickets about
 improving type error messages]

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/16374#comment:2>
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