[GHC] #14670: -XRebindableSyntax needs return?

[GHC]

#14670: -XRebindableSyntax needs return?
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        Reporter:  jackkelly         |                Owner:  (none)
            Type:  bug               |               Status:  new
        Priority:  normal            |            Milestone:  8.6.1
       Component:  Compiler          |              Version:  8.2.2
      Resolution:                    |             Keywords:
                                     |  RebindableSyntax
Operating System:  Unknown/Multiple  |         Architecture:
                                     |  Unknown/Multiple
 Type of failure:  GHC rejects       |            Test Case:
  valid program                      |  rebindable/T14670
      Blocked By:                    |             Blocking:
 Related Tickets:                    |  Differential Rev(s):
       Wiki Page:                    |
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Comment (by dfeuer):

 I see that in `compiler/rename/RnExpr.hs` there's a "TODO: I don't know
 how to get this right for rebindable syntax", but I don't think any of
 that is supposed to be used without `ApplicativeDo`. I haven't yet been
 able to find a place where `ApplicativeDo` checking obviously leaks out
 elsewhere.

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/14670#comment:2>
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