[GHC] #14387: listToMaybe doesn't participate in foldr/build fusion

[GHC]

#14387: listToMaybe doesn't participate in foldr/build fusion
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        Reporter:  duog              |                Owner:  duog
            Type:  bug               |               Status:  patch
        Priority:  normal            |            Milestone:
       Component:  Core Libraries    |              Version:  8.2.1
      Resolution:                    |             Keywords:
Operating System:  Unknown/Multiple  |         Architecture:
                                     |  Unknown/Multiple
 Type of failure:  None/Unknown      |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:                    |  Differential Rev(s):  Phab:D4126
       Wiki Page:                    |
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Comment (by Ben Gamari <ben@…>):

 In [changeset:"4c06ccb71737b77a8165e888ad75417a425549dd/ghc" 4c06ccb/ghc]:
 {{{
 #!CommitTicketReference repository="ghc"
 revision="4c06ccb71737b77a8165e888ad75417a425549dd"
 base: Enable listToMaybe to fuse via foldr/build

 Test Plan: Consider whether this is a good idea.

 Reviewers: austin, hvr, bgamari, nomeata

 Reviewed By: bgamari, nomeata

 Subscribers: nomeata, rwbarton, thomie

 GHC Trac Issues: #14387

 Differential Revision: https://phabricator.haskell.org/D4126
 }}}

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/14387#comment:5>
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