[GHC] #11098: PartialTypeSignatures mishandles type variables that begin with an underscore

[GHC]

#11098: PartialTypeSignatures mishandles type variables that begin with an
underscore
-------------------------------------+-------------------------------------
        Reporter:  goldfire          |                Owner:  msosn
            Type:  bug               |               Status:  closed
        Priority:  normal            |            Milestone:  8.0.1
       Component:  Template Haskell  |              Version:  7.10.2
      Resolution:  fixed             |             Keywords:
Operating System:  Unknown/Multiple  |         Architecture:
                                     |  Unknown/Multiple
 Type of failure:  None/Unknown      |            Test Case:  T11098,
                                     |  NamedWildcardsAsTyVars,
                                     |  NamedWildcardExplicitForall
      Blocked By:                    |             Blocking:
 Related Tickets:                    |  Differential Rev(s):  Phab:D1576
       Wiki Page:                    |
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Comment (by Simon Peyton Jones <simonpj@…>):

 In [changeset:"575a98e4d245c1e60526ed6d6711d96cea08e9d2/ghc"
 575a98e4/ghc]:
 {{{
 #!CommitTicketReference repository="ghc"
 revision="575a98e4d245c1e60526ed6d6711d96cea08e9d2"
 Refactor named wildcards (again)

 Michal's work on #10982, #11098, refactored the handling of named
 wildcards by making them more like ordinary type variables.

 This patch takes the same idea to its logical conclusion, resulting
 in a much tidier, tighter implementation.

 Read Note [The wildcard story for types] in HsTypes.

 Changes:

  * Named wildcards are ordinary type variables, throughout

  * HsType no longer has a data constructor for named wildcards
    (was NamedWildCard in HsWildCardInfo).  Named wildcards are
    simply HsTyVars

  * Similarly named wildcards disappear from Template Haskell

  * I refactored RnTypes to avoid polluting LocalRdrEnv with something
    as narrow as named wildcards.  Instead the named wildcard set is
    carried in RnTyKiEnv.

 There is a submodule update for Haddock.
 }}}

--
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/11098#comment:11>
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