[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 f-a):

 Thanks ulysses4ever

 Replying to [comment:2 ulysses4ever]:
 > Also, Haskell Report (the Haskell standard) says that `sum` should
 behave lazily (AFAIK). So, changing the behavior of `sum` seems a bit of
 extreme to me. I'd rather argue for adding `sum' / product'` to `Prelude`.

 I thought the same, but:


 {{{
 -- from page 192 of the "Haskell 2010 Language Report"
 sum :: Num a => [a] -> a
     The sum function computes the sum of a finite list of numbers.
 }}}

 Is mandatory laziness stated somewhere else?

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/15521#comment:3>
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