[GHC] #15415: GHCi's :kind doesn't work with wildcards

[GHC]

#15415: GHCi's :kind doesn't work with wildcards
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        Reporter:  goldfire          |                Owner:  (none)
            Type:  bug               |               Status:  new
        Priority:  normal            |            Milestone:  8.6.1
       Component:  Compiler          |              Version:  8.5
      Resolution:                    |             Keywords:
Operating System:  Unknown/Multiple  |         Architecture:
                                     |  Unknown/Multiple
 Type of failure:  None/Unknown      |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:                    |  Differential Rev(s):
       Wiki Page:                    |
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Comment (by simonpj):

 >  I would just fix this myself, but it smells intentional. Does anyone
 know why we have all this?

 I've had a look.  Just fix it yourself... I have no idea why `tcRnType`
 should use a subtly-different interface for `tcWildCardBinders`.  I
 suspect it's accidental.

 I note also that

 * All the other calls to `tcWildCardBindersX` pass in `newWildTyVar`.  If
 that's what we want in `tcRnType` (and I bet it is) we can just remove the
 parameter from `tcWildCardBindersX` and use `newWildTyVar` directly.

 *  There is another subtle difference: only the call from `tcRnType`
 passes in some skolem-info, and the effect of that is to use
 `scopeTyVars2` which builds an implication etc. I bet this is accidental
 (and wrong) too.  We probably don't need that skolem-info at all.

 Over to you!

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/15415#comment:4>
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