[GHC] #11982: Typechecking fails for parallel monad comprehensions with polymorphic let (GHC 7.10.3 through 8.6.3)

[GHC]

#11982: Typechecking fails for parallel monad comprehensions with polymorphic let
(GHC 7.10.3 through 8.6.3)
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        Reporter:  simonpj           |                Owner:  josefs
            Type:  bug               |               Status:  new
        Priority:  normal            |            Milestone:
       Component:  Compiler          |              Version:  7.10.3
      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):
       Wiki Page:                    |
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Comment (by Ben Gamari <ben@…>):

 In [changeset:"def84a10dd9db34d86284cb0b8358261034eecc4/ghc" def84a1/ghc]:
 {{{
 #!CommitTicketReference repository="ghc"
 revision="def84a10dd9db34d86284cb0b8358261034eecc4"
 testsuite: Add tests from #11982
 }}}

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Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/11982#comment:21>
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