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Re: To use Perl like conditional assignment in C

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Uno wrote:
> 
> On 9/24/2011 4:48 AM, pete wrote:
> > Ya Shou wrote:
> >>
> >> Hello,
> >>
> >> I want to assign an uncertain value to a variable, this variable with
> >> values in the configuration file, reads the configuration file
> >> through a function to return to the read configuration value, if not
> >> configured or the value of non-compliance, will return 0 for failure,
> >> when this, I will to give it a default value assigned.
> >>
> >> However, I found it seem impossible to achieve this in C, but much
> >> easier to implement in Perl, see below:
> >>
> >> cfgval = loadConfig () || DEFAULT_VAL;
> >>
> >> In C '||' operator does not return the value of the expression which
> >> is true, but returns 1 or 0, so that I can not be used in a similar
> >> way. I considered a program in C is:
> >>
> >> cfgval = loadConfig ()? loadConfig (): DEFAULT_VAL;
> >>
> >> And however, this approach to involve a duplication of code, it is
> >> ugly, the other will call loadConfig function twice, inefficient and
> >> likely to cause unnecessary accidents.
> >>
> >> Of course, if / else statement can achieve this functionality, but
> >> this method requires an additional variable, and not look simple. As
> >> follows:
> >>
> >> int loadval = loadConfig ();
> >> if (loadval! = 0) {
> >>     cfgval = loadval;
> >> } else {
> >>     cfgval = DEFAULT_VAL;
> >> }
> >>
> >> Or
> >>
> >> int loadval;
> >> cfgval = (loadval! = 0)? loadval: DEFAULT_VAL;
> >>
> >> I would like to ask you is, in this case, there is nothing more
> >> beautiful realization?
> >
> >      cfgval = loadConfig ();
> >      if (cfgval == 0) {
> >          cfgval = DEFAULT_VAL;
> >      }
> >
> 
> pete,
> 
> you just posted another syntax other than c tonight in clc; watch it,
> there, revolutionary.

I don't think that I did that.

-- 
pete

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Thread

To use Perl like conditional assignment in C Ya Shou <shouyatf@gmail.com> - 2011-09-24 04:06 -0700
  Re: To use Perl like conditional assignment in C Willem <willem@toad.stack.nl> - 2011-09-24 11:13 +0000
  Re: To use Perl like conditional assignment in C pete <pfiland@mindspring.com> - 2011-09-24 07:48 -0400
    Re: To use Perl like conditional assignment in C Uno <merrilljensen@q.com> - 2011-09-24 21:58 -0700
      Re: To use Perl like conditional assignment in C pete <pfiland@mindspring.com> - 2011-09-25 08:44 -0400
        Re: To use Perl like conditional assignment in C Uno <merrilljensen@q.com> - 2011-09-26 21:52 -0700
          Re: To use Perl like conditional assignment in C pete <pfiland@mindspring.com> - 2011-09-27 21:14 -0400
            Re: To use Perl like conditional assignment in C Keith Thompson <kst-u@mib.org> - 2011-09-27 19:56 -0700
      Re: To use Perl like conditional assignment in C Nick Keighley <nick_keighley_nospam@hotmail.com> - 2011-09-25 06:53 -0700
      Re: To use Perl like conditional assignment in C "J. J. Farrell" <jjf@bcs.org.uk> - 2011-09-26 04:40 +0100
  Re: To use Perl like conditional assignment in C Eric Sosman <esosman@ieee-dot-org.invalid> - 2011-09-24 09:04 -0400
    Re: To use Perl like conditional assignment in C Willem <willem@toad.stack.nl> - 2011-09-24 14:06 +0000
    Re: To use Perl like conditional assignment in C Ya Shou <shouyatf@gmail.com> - 2011-09-26 21:10 -0700
    Re: To use Perl like conditional assignment in C Jorgen Grahn <grahn+nntp@snipabacken.se> - 2011-09-29 22:08 +0000
  Re: To use Perl like conditional assignment in C "BartC" <bc@freeuk.com> - 2011-09-26 01:37 +0100

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