[GHC] #14729: normaliseType is not well-kinded

[GHC]

#14729: normaliseType is not well-kinded
-------------------------------------+-------------------------------------
           Reporter:  goldfire       |             Owner:  (none)
               Type:  bug            |            Status:  new
           Priority:  normal         |         Milestone:
          Component:  Compiler       |           Version:  8.2.2
           Keywords:                 |  Operating System:  Unknown/Multiple
       Architecture:                 |   Type of failure:  None/Unknown
  Unknown/Multiple                   |
          Test Case:                 |        Blocked By:
           Blocking:                 |   Related Tickets:
Differential Rev(s):                 |         Wiki Page:
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 Suppose we have

 {{{
 Proxy :: forall k. k -> Type

 type family F a
 type instance F Int = Bool
 }}}

 and we're trying to normalise the target

 {{{
 Proxy (F Int) x
 }}}

 Clearly, for this target to be well kinded, we need `x :: F Int`.
 Currently, the output of `normaliseType` is `Proxy Bool x`, which is just
 plain wrong.

 I need to implement logic like in `flatten_args` on
 [https://github.com/goldfirere/ghc my branch] in `normaliseType` to fix
 this.

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/14729>
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