[GHC] #14968: QuantifiedConstraints: Can't be RHS of type family instances

[GHC]

#14968: QuantifiedConstraints: Can't be RHS of type family instances
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        Reporter:  josef             |                Owner:  (none)
            Type:  bug               |               Status:  new
        Priority:  normal            |            Milestone:
       Component:  Compiler (Type    |              Version:  8.5
  checker)                           |             Keywords:
      Resolution:                    |  QuantifiedConstraints
Operating System:  Unknown/Multiple  |         Architecture:
                                     |  Unknown/Multiple
 Type of failure:  None/Unknown      |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:  #9269             |  Differential Rev(s):
       Wiki Page:                    |
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Changes (by RyanGlScott):

 * related:   => #9269


Comment:

 This is a particular occurrence of a more general restriction, which is
 explained in https://ghc.haskell.org/trac/ghc/ticket/9269#comment:1. So
 yes, there are fundamental difficulties here that have yet to be worked
 out.

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/14968#comment:1>
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