[GHC] #13511: ApplicativeDo return case doesn't handle lets

[GHC]

#13511: ApplicativeDo return case doesn't handle lets
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        Reporter:  mnislaih          |                Owner:  (none)
            Type:  feature request   |               Status:  new
        Priority:  normal            |            Milestone:  8.4.1
       Component:  Compiler          |              Version:  8.0.2
      Resolution:                    |             Keywords:  ApplicativeDo
Operating System:  Unknown/Multiple  |         Architecture:
                                     |  Unknown/Multiple
 Type of failure:  None/Unknown      |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:                    |  Differential Rev(s):
       Wiki Page:                    |
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Comment (by simonmar):

 It depends what you mean by "doesn't handle".  It does have some
 heuristics to collect let bindings and prevent them from causing spurious
 dependencies, but that's aimed more at using Applicative with Monad,
 rather than the Applicative-only context.

 If there's a way to expand the desugaring that would also be simple to
 describe, then I wouldn't be averse to adding it.

--
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/13511#comment:9>
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