[GHC] #3263: Warnings for monadic values not used

[GHC]

#3263: Warnings for monadic values not used
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    Reporter:  NeilMitchell      |        Owner:  igloo           
        Type:  feature request   |       Status:  new             
    Priority:  normal            |    Milestone:                  
   Component:  Compiler          |      Version:  6.10.2          
    Severity:  normal            |   Resolution:                  
    Keywords:                    |   Difficulty:  Unknown         
    Testcase:                    |           Os:  Unknown/Multiple
Architecture:  Unknown/Multiple  |  
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Changes (by igloo):

  * owner:  => igloo

Comment:

 Re:
 {{{
 evaluate -- Returns the thing on the input. Perhaps we should provide
 force :: a -> IO () as an alternative
 }}}
 I think that actually you are meant to use the returned value rather than
 the input value, as otherwise inlining can defeat the purpose of the
 forcing. See #2273 for more.

-- 
Ticket URL: <http://hackage.haskell.org/trac/ghc/ticket/3263#comment:8>
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