Re: C++ comma operator ?

From	Manfred <noname@add.invalid>
Newsgroups	comp.lang.c++
Subject	Re: C++ comma operator ?
Date	2022-10-01 01:03 +0200
Organization	Aioe.org NNTP Server
Message-ID	<th7skd$1rh2$1@gioia.aioe.org> (permalink)
References	<th5sej$tqvo$1@dont-email.me> <th5tfi$u0ms$1@dont-email.me>

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On 9/30/2022 7:05 AM, James Kuyper wrote:
> On 9/30/22 00:48, Lynn McGuire wrote:
>> Is this C++ statement using the comma operator ?
>>
>>         write(6, "(3(1x,i3),1x,f12.6,1x,f12.6)"), hkl(1, i), hkl(2, i),
>>           hkl(3, i), f_calc(1, i), f_calc(2, i);
>>
>> There is a large open source template library supporting this statement
>> from Fortran to C++ Fable software.
> 
> 
> 
> If write, hkl, and f_calc are macros, you cannot be sure without
> examining the macro definitions. However, if any of those three is an
> ordinary function, it seems to me that this statement does unnecessarily
> use the comma operator.
> 

"unnecessarily" is not necessarily true here: others have mentioned an 
overloaded comma operator.
/If/ this is what is actually going on here, then you might need to keep 
the sequence of commas in place, or go through some nontrivial rewrite.

Thread

C++ comma operator ? Lynn McGuire <lynnmcguire5@gmail.com> - 2022-09-29 23:48 -0500
  Re: C++ comma operator ? Lynn McGuire <lynnmcguire5@gmail.com> - 2022-09-30 00:01 -0500
    Re: C++ comma operator ? Lynn McGuire <lynnmcguire5@gmail.com> - 2022-09-30 00:03 -0500
  Re: C++ comma operator ? James Kuyper <jameskuyper@alumni.caltech.edu> - 2022-09-30 01:05 -0400
    Re: C++ comma operator ? red floyd <no.spam.here@its.invalid> - 2022-09-29 22:45 -0700
      Re: C++ comma operator ? scott@slp53.sl.home (Scott Lurndal) - 2022-09-30 15:16 +0000
        Re: C++ comma operator ? Lynn McGuire <lynnmcguire5@gmail.com> - 2022-09-30 13:53 -0500
          Re: C++ comma operator ? Gawr Gura <gawrgura@mail.hololive.com> - 2022-09-30 13:17 -0700
          Re: C++ comma operator ? scott@slp53.sl.home (Scott Lurndal) - 2022-10-01 16:56 +0000
            Re: C++ comma operator ? Lynn McGuire <lynnmcguire5@gmail.com> - 2022-10-01 13:13 -0500
            Re: C++ comma operator ? Tim Rentsch <tr.17687@z991.linuxsc.com> - 2022-10-03 02:32 -0700
              Re: C++ comma operator ? Juha Nieminen <nospam@thanks.invalid> - 2022-10-03 10:48 +0000
    Re: C++ comma operator ? Lynn McGuire <lynnmcguire5@gmail.com> - 2022-09-30 13:32 -0500
      Re: C++ comma operator ? Lynn McGuire <lynnmcguire5@gmail.com> - 2022-10-01 14:30 -0500
        Re: C++ comma operator ? James Kuyper <jameskuyper@alumni.caltech.edu> - 2022-10-02 16:08 -0400
    Re: C++ comma operator ? Manfred <noname@add.invalid> - 2022-10-01 01:03 +0200
      Re: C++ comma operator ? Lynn McGuire <lynnmcguire5@gmail.com> - 2022-09-30 23:09 -0500
  Re: C++ comma operator ? Gawr Gura <gawrgura@mail.hololive.com> - 2022-09-29 23:19 -0700
    Re: C++ comma operator ? Lynn McGuire <lynnmcguire5@gmail.com> - 2022-09-30 13:31 -0500
  Re: C++ comma operator ? Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2022-09-30 12:41 -0700
    Re: C++ comma operator ? Tim Rentsch <tr.17687@z991.linuxsc.com> - 2022-10-03 02:38 -0700
  Re: C++ comma operator ? Lynn McGuire <lynnmcguire5@gmail.com> - 2022-09-30 23:48 -0500

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