[GHC] #4507: Data.List.sum and Data.List.product unnecessarily inefficient

[GHC]

#4507: Data.List.sum and Data.List.product unnecessarily inefficient
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  Reporter:  pozorvlak       |          Owner:                                 
      Type:  bug             |         Status:  closed                         
  Priority:  normal          |      Milestone:                                 
 Component:  libraries/base  |        Version:  7.0.1                          
Resolution:  wontfix         |       Keywords:  Data.List, sum, product, foldl'
  Testcase:                  |      Blockedby:                                 
Difficulty:                  |             Os:  Unknown/Multiple               
  Blocking:                  |   Architecture:  Unknown/Multiple               
   Failure:  None/Unknown    |  
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Comment(by igloo):

 Replying to [comment:2 pozorvlak]:
 > I am confused. The Haskell 2010 Language Report section on Data.List
 (http://www.haskell.org/onlinereport/haskell2010/haskellch20.html#x28-23100020.3)
 doesn't say anything about the strictness of sum or product that I can
 see: the Haskell 1998 Report doesn't mention Data.List at all. Where
 should I be looking? Note that I'm talking about the sum and product
 defined in Data.List, not the ones in the Prelude.

 I'm sure they're intended to be the same.

 It's unfortunate that H2010 no longer has reference implementations for
 the functions it defines.

-- 
Ticket URL: <http://hackage.haskell.org/trac/ghc/ticket/4507#comment:3>
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