[GHC] #13872: Strange Typeable error message involving TypeInType

[GHC]

#13872: Strange Typeable error message involving TypeInType
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        Reporter:  RyanGlScott       |                Owner:  (none)
            Type:  bug               |               Status:  new
        Priority:  normal            |            Milestone:
       Component:  Compiler (Type    |              Version:  8.0.1
  checker)                           |             Keywords:  TypeInType,
      Resolution:                    |  Typeable
Operating System:  Unknown/Multiple  |         Architecture:
 Type of failure:  Poor/confusing    |  Unknown/Multiple
  error message                      |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:                    |  Differential Rev(s):
       Wiki Page:                    |
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Comment (by bgamari):

 `<>` is what the type pretty-printer calls `Coercion` types. AFAICT it's
 not entirely trivial making this `Typeable`, since the constructor's
 actual kind does indeed contain a coercion.

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Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/13872#comment:1>
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