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Re: Need your experience: is "(void)param;" to avoid unused variable warnings well known for you?

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On Monday, April 2, 2012 6:39:50 AM UTC-5, F.Zwarts wrote:
> I have never seen this trick. Why don't you use the standard C++ way? Remove 
> the name of the parameter and the compiler will stop complaining. Less code, 
> better readability. The "(void)param" makes me wonder what the purpose is. 
> You will need comments to explain why it is used. If the parameter name is 
> omitted, it is immediately clear that it is not used in the function. No 
> comments needed. For the reason why it is not used in the function, comments 
> may be needed in both cases.
> 
> void someFunction(int)
> {
> 
> //
> }

Usually this only a problem in #ifdef'ed code.  E.g.

void someFunction(int wparam)
{
#ifdef _WIN32
  ...
#else
  // Only need this parameter on Windows.
  (void)wparam;
#endif
}

This works on most compilers but the only technique that I know of that works on all compilers is this:

namespace my {
  template <typename T> inline void unused(const T&) {}
}

...

  my::unused(wparam);


Mike

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Need your experience: is "(void)param;" to avoid unused variable warnings well known for you? Qi <no@no.com> - 2012-04-02 19:16 +0800
  Re: Need your experience: is "(void)param;" to avoid unused variable warnings well known for you? "Fred Zwarts \(KVI\)" <F.Zwarts@KVI.nl> - 2012-04-02 13:39 +0200
    Re: Need your experience: is "(void)param;" to avoid unused variable warnings well known for you? Victor Bazarov <v.bazarov@comcast.invalid> - 2012-04-02 09:49 -0400
      Re: Need your experience: is "(void)param;" to avoid unused variable warnings well known for you? Qi <no@no.com> - 2012-04-02 22:01 +0800
        Re: Need your experience: is "(void)param;" to avoid unused variable warnings well known for you? Victor Bazarov <v.bazarov@comcast.invalid> - 2012-04-02 11:50 -0400
        Re: Need your experience: is "(void)param;" to avoid unused variable warnings well known for you? Paul N <gw7rib@aol.com> - 2012-04-02 12:54 -0700
      Re: Need your experience: is "(void)param;" to avoid unused variable warnings well known for you? Juha Nieminen <nospam@thanks.invalid> - 2012-04-03 05:27 +0000
        Re: Need your experience: is "(void)param;" to avoid unused variable warnings well known for you? Jorgen Grahn <grahn+nntp@snipabacken.se> - 2012-04-03 08:02 +0000
          Re: Need your experience: is "(void)param;" to avoid unused variable warnings well known for you? Juha Nieminen <nospam@thanks.invalid> - 2012-04-03 14:19 +0000
    Re: Need your experience: is "(void)param;" to avoid unused variable warnings well known for you? Mike McCarty <mcmccarty@gmail.com> - 2012-04-02 06:43 -0700
  Re: Need your experience: is "(void)param;" to avoid unused variable warnings well known for you? GM <GM@no.spam.it> - 2012-04-02 14:41 +0200
  Re: Need your experience: is "(void)param;" to avoid unused variable warnings well known for you? bartek szurgot <basz@no.spam> - 2012-04-02 16:55 +0200
    Re: Need your experience: is "(void)param;" to avoid unused variable warnings well known for you? Juha Nieminen <nospam@thanks.invalid> - 2012-04-03 05:28 +0000
      Re: Need your experience: is "(void)param;" to avoid unused variable warnings well known for you? Qi <no@no.com> - 2012-04-03 13:54 +0800
        Re: Need your experience: is "(void)param;" to avoid unused variable warnings well known for you? Juha Nieminen <nospam@thanks.invalid> - 2012-04-03 14:09 +0000
          Re: Need your experience: is "(void)param;" to avoid unused variable warnings well known for you? Robert Wessel <robertwessel2@yahoo.com> - 2012-04-03 11:21 -0500
            Re: Need your experience: is "(void)param;" to avoid unused variable warnings well known for you? bartek szurgot <basz@no.spam> - 2012-04-04 17:39 +0200
  Re: Need your experience: is "(void)param;" to avoid unused variable warnings well known for you? Jorgen Grahn <grahn+nntp@snipabacken.se> - 2012-04-02 15:13 +0000
  Re: Need your experience: is "(void)param;" to avoid unused variable warnings well known for you? "MikeWhy" <boat042-nospam@yahoo.com> - 2012-04-02 11:37 -0500
    Re: Need your experience: is "(void)param;" to avoid unused variable warnings well known for you? Qi <no@no.com> - 2012-04-03 10:29 +0800
      Re: Need your experience: is "(void)param;" to avoid unused variable warnings well known for you? "Alf P. Steinbach" <alf.p.steinbach+usenet@gmail.com> - 2012-04-03 06:00 +0200
        Re: Need your experience: is "(void)param;" to avoid unused variable warnings well known for you? Qi <no@no.com> - 2012-04-03 13:56 +0800
  Re: Need your experience: is "(void)param;" to avoid unused variable warnings well known for you? goran.pusic@gmail.com - 2012-04-02 04:25 -0700
    Re: Need your experience: is "(void)param;" to avoid unused variable warnings well known for you? scott@slp53.sl.home (Scott Lurndal) - 2012-04-02 22:01 +0000
  Re: Need your experience: is "(void)param;" to avoid unused variable warnings well known for you? Öö Tiib <ootiib@hot.ee> - 2012-04-02 07:37 -0700
  Re: Need your experience: is "(void)param;" to avoid unused variable warnings well known for you? Dombo <dombo@disposable.invalid> - 2012-04-03 19:35 +0200
  Re: Need your experience: is "(void)param;" to avoid unused variable warnings well known for you? Stuart Redmann <DerTopper@web.de> - 2012-04-04 11:56 -0700
  Re: Need your experience: is "(void)param;" to avoid unused variable warnings well known for you? Qi <no@no.no> - 2012-04-05 14:17 +0800

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