[GHC] #11607: ApplicativeDo easily foiled with `pure`

[GHC]

#11607: ApplicativeDo easily foiled with `pure`
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        Reporter:  bgamari           |                Owner:  bgamari
            Type:  bug               |               Status:  patch
        Priority:  high              |            Milestone:  8.0.1
       Component:  Compiler (Type    |              Version:  8.0.1-rc2
  checker)                           |
      Resolution:                    |             Keywords:  ApplicativeDo
Operating System:  Unknown/Multiple  |         Architecture:
 Type of failure:  GHC rejects       |  Unknown/Multiple
  valid program                      |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:                    |  Differential Rev(s):  Phab:D1931
       Wiki Page:                    |
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Changes (by bgamari):

 * status:  new => patch
 * differential:   => Phab:D1931


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Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/11607#comment:3>
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