[GHC] #11216: RebindableSyntax with pattern guards needs `fail`

[GHC]

#11216: RebindableSyntax with pattern guards needs `fail`
-------------------------------------+-------------------------------------
        Reporter:  goldfire          |                Owner:
            Type:  bug               |               Status:  patch
        Priority:  normal            |            Milestone:  8.2.1
       Component:  Compiler          |              Version:  7.11
      Resolution:                    |             Keywords:
                                     |  RebindableSyntax
Operating System:  Unknown/Multiple  |         Architecture:
                                     |  Unknown/Multiple
 Type of failure:  None/Unknown      |            Test Case:  T11216,
                                     |  T11216A
      Blocked By:                    |             Blocking:
 Related Tickets:                    |  Differential Rev(s):  Phab:D2896
       Wiki Page:                    |
-------------------------------------+-------------------------------------

Comment (by Ben Gamari <ben@…>):

 In [changeset:"8f89e76389569b73ce0d7550302641bbea438dfc/ghc" 8f89e76/ghc]:
 {{{
 #!CommitTicketReference repository="ghc"
 revision="8f89e76389569b73ce0d7550302641bbea438dfc"
 rename: Don't require 'fail' in non-monadic contexts

 Fixes #11216.
 }}}

--
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/11216#comment:7>
GHC <http://www.haskell.org/ghc/>
The Glasgow Haskell Compiler