[GHC] #4370: Bring back monad comprehensions

[GHC]

#4370: Bring back monad comprehensions
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        Reporter:  simonpj           |                Owner:
            Type:  feature request   |               Status:  patch
        Priority:  normal            |            Milestone:  ⊥
       Component:  Compiler          |              Version:  6.12.3
      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:D2247
       Wiki Page:                    |
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Changes (by bgamari):

 * status:  new => patch
 * differential:   => Phab:D2247


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Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/4370#comment:70>
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