[GHC] #14386: GHC doesn't allow Coercion between partly-saturated type constructors

[GHC]

#14386: GHC doesn't allow Coercion between partly-saturated type constructors
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        Reporter:  Iceland_jack      |                Owner:  (none)
            Type:  bug               |               Status:  new
        Priority:  normal            |            Milestone:
       Component:  Compiler          |              Version:  8.3
      Resolution:                    |             Keywords:  roles
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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Comment (by goldfire):

 This seems to be yet another way representational equality could,
 theoretically, expand.

 Note that, unlike certain other problems, this isn't a limitation of the
 solver, but of the definition of the equality relation itself. It might be
 helpful to maintain a list of such deficiencies.

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/14386#comment:6>
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