[GHC] #10114: Kind mismatches with AnyK in rank-2 types

[GHC]

#10114: Kind mismatches with AnyK in rank-2 types
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        Reporter:  cam               |                   Owner:
            Type:  bug               |                  Status:  new
        Priority:  normal            |               Milestone:
       Component:  Compiler          |                 Version:  7.8.4
      Resolution:                    |                Keywords:
Operating System:  Unknown/Multiple  |            Architecture:
 Type of failure:  GHC rejects       |  Unknown/Multiple
  valid program                      |               Test Case:
      Blocked By:                    |                Blocking:
 Related Tickets:                    |  Differential Revisions:
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Comment (by simonpj):

 NB the [https://downloads.haskell.org/~ghc/latest/docs/html/users_guide
 /kind-polymorphism.html rule for kind generalisation in 7.8.2 of the user
 manual].
 {{{
 f1 :: (forall a.      Proxy a) -> Int    -- Means  f :: forall k. (forall
 (a:k). Proxy k a) -> Int
 f2 :: (forall (a::k). Proxy a) -> Int    -- Means  f :: (forall k. forall
 (a:k). Proxy k a) -> Int
 }}}
 (Richard's new branch, which collapses types and kinds, allows explicit
 kind quantification, so we can then control this more explicitly.)

 So maybe the same should be true for `T`:
 {{{
 type T = forall f a. f a       -- Means type T k = forall (f::k->*)
 (a::k). f a
 type T = forall f (a::k). f a  -- Means type T = forall k (f::k->*)
 (a::k). f a
 }}}

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Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/10114#comment:9>
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