[GHC] #9293: GHCI :unset -XLanguageExtension returns "don't know how to reverse -XLanguageExtension"

[GHC]

#9293: GHCI :unset -XLanguageExtension returns "don't know how to reverse
-XLanguageExtension"
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              Reporter:  jfeltz            |            Owner:  leroux
                  Type:  bug               |           Status:  patch
              Priority:  normal            |        Milestone:
             Component:  GHCi              |          Version:  7.8.2
            Resolution:                    |         Keywords:  newcomer
      Operating System:  Unknown/Multiple  |     Architecture:  x86
       Type of failure:  None/Unknown      |       Difficulty:  Unknown
             Test Case:  T9293             |       Blocked By:
              Blocking:                    |  Related Tickets:
Differential Revisions:  Phab:D516         |
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Comment (by Austin Seipp <austin@…>):

 In [changeset:"3e4f49b04e6e97256b4d34221e209e1051bf06ae/ghc"]:
 {{{
 #!CommitTicketReference repository="ghc"
 revision="3e4f49b04e6e97256b4d34221e209e1051bf06ae"
 Fixes ghci :unset -X<ext> so that it doesn't fail to reverse option.
 (fixes trac #9293)

 Summary: ghci unset could not reverse language extensions.

 Reviewers: hvr, thomie, austin

 Reviewed By: hvr, thomie, austin

 Subscribers: goldfire, hvr, thomie, carter

 Differential Revision: https://phabricator.haskell.org/D516

 GHC Trac Issues: #9293
 }}}

--
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/9293#comment:6>
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