[GHC] #15658: strange inferred kind with TypeInType

[GHC]

#15658: strange inferred kind with TypeInType
-------------------------------------+-------------------------------------
           Reporter:  dmwit          |             Owner:  (none)
               Type:  bug            |            Status:  new
           Priority:  normal         |         Milestone:  8.6.1
          Component:  Compiler       |           Version:  8.4.2
           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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 This type family has a strange kind to begin with:

 {{{
 {-# Language TypeFamilies , TypeInType #-}
 type family F f a :: a
 }}}

 But it gets even stranger when you ask ghci what it thinks about F:

 {{{
 > :k F
 F :: * -> forall a -> a
 }}}

 There is a forall which doesn't seem to bind any variables and hasn't got
 the customary delimiting dot.

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/15658>
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