[GHC] #10519: Can't put wildcard behind forall

[GHC]

#10519: Can't put wildcard behind forall
-------------------------------------+-------------------------------------
        Reporter:  yongqli           |                   Owner:  thomasw
            Type:  bug               |                  Status:  new
        Priority:  normal            |               Milestone:
       Component:  Compiler          |                 Version:  7.10.1-rc3
      Resolution:                    |                Keywords:
Operating System:  Unknown/Multiple  |            Architecture:
 Type of failure:  None/Unknown      |  Unknown/Multiple
      Blocked By:                    |               Test Case:
 Related Tickets:                    |                Blocking:
                                     |  Differential Revisions:  Phab:D994
-------------------------------------+-------------------------------------

Comment (by Ben Gamari <ben@…>):

 In [changeset:"f8563838603f9a60f5012c3837142c5df89b8de2/ghc"]:
 {{{
 #!CommitTicketReference repository="ghc"
 revision="f8563838603f9a60f5012c3837142c5df89b8de2"
 Fix Trac #10519

 Look through nested foralls when checking the validity of a partial type
 signature. The combination of D836 and D613 prompts this change.

 Test Plan: The test T10519 must pass

 Reviewers: simonpj, alanz, austin

 Reviewed By: simonpj, alanz, austin

 Subscribers: thomie, bgamari

 Differential Revision: https://phabricator.haskell.org/D994

 GHC Trac Issues: #10519
 }}}

--
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/10519#comment:4>
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