[GHC] #13399: Location of `forall` matters with higher-rank kind polymorphism

[GHC]

#13399: Location of `forall` matters with higher-rank kind polymorphism
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        Reporter:  crockeea          |                Owner:  (none)
            Type:  bug               |               Status:  new
        Priority:  normal            |            Milestone:
       Component:  Compiler          |              Version:  8.0.2
      Resolution:                    |             Keywords:  TypeInType
Operating System:  Unknown/Multiple  |         Architecture:
 Type of failure:  GHC rejects       |  Unknown/Multiple
  valid program                      |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:                    |  Differential Rev(s):
       Wiki Page:                    |
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Comment (by RyanGlScott):

 Thanks Richard, that's a tremendously helpful explanation. So to recap,
 there are three bugs:

 * crockeea was unable to figure out that this is expected behavior. We
 should document this behavior of higher-rank kinds.
 * There is a bug in how higher-rank kinds are pretty-printed (comment:5)
 * Type synonyms don't obey the "one-equation-rule" (as defined in
 comment:6)

 Should we open separate tickets for the last two?

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Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/13399#comment:7>
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