[GHC] #13337: GHC doesn't think a type is of kind *, despite having evidence for it

[GHC]

#13337: GHC doesn't think a type is of kind *, despite having evidence for it
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        Reporter:  RyanGlScott       |                Owner:  (none)
            Type:  bug               |               Status:  new
        Priority:  normal            |            Milestone:
       Component:  Compiler (Type    |              Version:  8.0.2
  checker)                           |
      Resolution:                    |             Keywords:
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 goldfire):

 For your first example: this infelicity is by design, though I can't find
 documentation in the manual. Equality assumptions (such as your `k ~
 Type`) come into scope only in an expression of that type, not later on in
 the same type. This design significantly eased the implementation.

 The second example should work -- that's a bug.

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Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/13337#comment:1>
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