[GHC] #15821: Implement more constant folding for Naturals

[GHC]

#15821: Implement more constant folding for Naturals
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        Reporter:  bgamari           |                Owner:  (none)
            Type:  task              |               Status:  new
        Priority:  normal            |            Milestone:  8.8.1
       Component:  Compiler          |              Version:  8.6.1
      Resolution:                    |             Keywords:  newcomer
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 martijnbastiaan):

 leonschool(@github) and I have been working on this when we discovered the
 missing foldings caused issues with the project we're working on. We've
 got a first implementation up:
 https://github.com/leonschoorl/ghc/commit/114981b040c8731702466246a0f7f6afb7874ac2
 (don't mind the trace calls, WIP!).

 @hsyl20, maybe we could work together?

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/15821#comment:4>
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