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Re: Unexpected output

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Ben Bacarisse wrote:
> 
> August Karlstrom <fusionfile@gmail.com> writes:
> 
> > On 2011-09-10 21:36, Mazen wrote:
> >> Hello,
> >>
> >> Following is a simple program:
> >>
> >> #include<stdio.h>
> >>
> >> int main(void) {
> >>    int i = 0, j, k;
> >>    j = k = 2;
> >>
> >>    printf("%d %d\n", i=+j, i=-j);
> >>
> >>    return 0;
> >> }
> >>
> >> The output is
> >> 2 2
> >>
> >> Shouldn't the second expression be -2 rather than 2? I'm confused.
> >> Your insights pls. Thanks!
> >
> > One obvious insight is that it's best to avoid side effects in
> > expressions if possible.
> 
> The devil is in the detail.  You presumably think that x = 1; is OK so
> what about x++? 

(x = 1) has a side effect in an expression.
I avoid side effects in arguments in function calls.

-- 
pete

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Unexpected output Mazen <neurohacks@gmail.com> - 2011-09-10 12:36 -0700
  Re: Unexpected output China Blue Corn Chips <chine.bleu@yahoo.com> - 2011-09-10 12:59 -0700
    Re: Unexpected output Eric Sosman <esosman@ieee-dot-org.invalid> - 2011-09-10 16:42 -0400
      Re: Unexpected output Mazen <neurohacks@gmail.com> - 2011-09-10 17:51 -0700
        Re: Unexpected output Joe Pfeiffer <pfeiffer@cs.nmsu.edu> - 2011-09-10 20:38 -0600
        Re: Unexpected output pete <pfiland@mindspring.com> - 2011-09-10 22:41 -0400
        Re: Unexpected output Eric Sosman <esosman@ieee-dot-org.invalid> - 2011-09-11 09:35 -0400
          Re: Unexpected output gazelle@shell.xmission.com (Kenny McCormack) - 2011-09-11 13:39 +0000
        Re: Unexpected output "BartC" <bc@freeuk.com> - 2011-09-11 15:26 +0100
      Re: Unexpected output Paul N <gw7rib@aol.com> - 2011-09-11 12:08 -0700
        Re: Unexpected output Eric Sosman <esosman@ieee-dot-org.invalid> - 2011-09-11 17:43 -0400
    Re: Unexpected output Mazen <neurohacks@gmail.com> - 2011-09-10 13:24 -0700
      Re: Unexpected output China Blue Corn Chips <chine.bleu@yahoo.com> - 2011-09-10 15:02 -0700
    Re: Unexpected output Kenneth Brody <kenbrody@spamcop.net> - 2011-09-12 10:01 -0400
  Re: Unexpected output arni <arnmin@gmail.com> - 2011-09-10 13:31 -0700
    Re: Unexpected output Eric Sosman <esosman@ieee-dot-org.invalid> - 2011-09-10 16:49 -0400
      Re: Unexpected output arni <arnmin@gmail.com> - 2011-09-10 14:13 -0700
        Re: Unexpected output Eric Sosman <esosman@ieee-dot-org.invalid> - 2011-09-10 17:26 -0400
          Re: Unexpected output Mazen <neurohacks@gmail.com> - 2011-09-10 17:59 -0700
            Re: Unexpected output Joe Pfeiffer <pfeiffer@cs.nmsu.edu> - 2011-09-10 20:52 -0600
              Re: Unexpected output China Blue Corn Chips <chine.bleu@yahoo.com> - 2011-09-10 19:55 -0700
              Re: Unexpected output Nick Keighley <nick_keighley_nospam@hotmail.com> - 2011-09-11 06:03 -0700
                Re: Unexpected output James Kuyper <jameskuyper@verizon.net> - 2011-09-11 14:04 -0400
            Re: Unexpected output Ben Bacarisse <ben.usenet@bsb.me.uk> - 2011-09-11 11:22 +0100
            Re: Unexpected output Keith Thompson <kst-u@mib.org> - 2011-09-11 11:01 -0700
              Re: Unexpected output Phil Carmody <thefatphil_demunged@yahoo.co.uk> - 2011-09-13 14:09 +0300
        Re: Unexpected output Seebs <usenet-nospam@seebs.net> - 2011-09-13 06:44 +0000
    Re: Unexpected output "Morris Keesan" <mkeesan@post.harvard.edu> - 2011-09-10 17:16 -0400
  Re: Unexpected output "BartC" <bc@freeuk.com> - 2011-09-10 23:20 +0100
  Re: Unexpected output August Karlstrom <fusionfile@gmail.com> - 2011-09-11 22:55 +0200
    Re: Unexpected output Ben Bacarisse <ben.usenet@bsb.me.uk> - 2011-09-11 22:51 +0100
      Re: Unexpected output pete <pfiland@mindspring.com> - 2011-09-11 22:25 -0400
      Re: Unexpected output August Karlstrom <fusionfile@gmail.com> - 2011-09-12 15:34 +0200
        Re: Unexpected output Ben Bacarisse <ben.usenet@bsb.me.uk> - 2011-09-12 19:55 +0100
          Re: Unexpected output August Karlstrom <fusionfile@gmail.com> - 2011-09-13 19:22 +0200

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