Re: [Boost-bugs] [Boost C++ Libraries] #4720: [function][patch] function wrapper with no exception safety guarantee

Subject: Re: [Boost-bugs] [Boost C++ Libraries] #4720: [function][patch] function wrapper with no exception safety guarantee
From: Boost C++ Libraries (noreply_at_[hidden])
Date: 2010-10-08 08:14:24

#4720: [function][patch] function wrapper with no exception safety guarantee
-------------------------------+--------------------------------------------
  Reporter:  djwalker          |       Owner:  dgregor 
      Type:  Feature Requests  |      Status:  new     
 Milestone:  To Be Determined  |   Component:  function
   Version:  Boost 1.44.0      |    Severity:  Problem 
Resolution:                    |    Keywords:          
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Comment (by peter.myerscough-jackopson@…):

 I like the concept of an entirely separate ''unsafe_function'', but I am
 also aware that the patch of #4646 would also enable benefits when the
 normal function object is used, for example a common idiom of using
 function objects is
 {{{
 if( funcObj )
 {
    funcObj(); // could be funcObj->unchecked_invoke();
 }
 }}}
 which would benefit from being an unchecked_invoke(), but I suppose that
 it may be simpler / cleaner to maintain the calling operator and allow an
 optimizer to remove the repeated checking of the funcObj's validity, but
 this does rely on the optimiser, which both gcc and msvc++ do.

 I think it would be worth placing some boost assertions in place of the
 previous checks so that debug code will catch and highlight the failure
 point.

-- 
Ticket URL: <https://svn.boost.org/trac/boost/ticket/4720#comment:1>
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