[GHC] #15521: Provide a strict version of sum

[GHC]

#15521: Provide a strict version of sum
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        Reporter:  dnadales          |                Owner:  (none)
            Type:  feature request   |               Status:  new
        Priority:  normal            |            Milestone:  8.6.1
       Component:  Prelude           |              Version:  8.4.3
      Resolution:                    |             Keywords:
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 ulysses4ever):

 Maybe the HR argument is not that important, because the
 [http://hackage.haskell.org/package/base-4.11.1.0/docs/src/Data.Foldable.html#sum
 actual definition] is far from HR anyway. Just some code could brake if
 you change the semantics (see above).

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/15521#comment:4>
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