Groups > comp.lang.c > #20443

Re: Operator precedence.

Message-ID	<4FA79A67.5017@mindspring.com> (permalink)
Date	2012-05-07 05:48 -0400
From	pete <pfiland@mindspring.com>
Organization	PF
Newsgroups	comp.lang.c
Subject	Re: Operator precedence.
References	<76630b90-04ab-4976-b1a0-76868d85ccf5@vy9g2000pbc.googlegroups.com>

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somenath wrote:
> 
> Hi All,
> 
> While browsing through the old article in this group I have come
> across  one article by Chrish Torek.
> http://groups.google.com/group/gnu.gcc.help/browse_thread/thread/31750b84b212325/d97a0f655e96ce16?lnk=gst&q=compiler+munching+%2B++chrish+torek#d97a0f655e96ce16
> 
> In this article he said.
> 
> "Finally, let me say one last time that the Standard C grammar DOES
> NOT use operator precedence.  (At most, one can say that the grammar
> "implies" a precedence.  I believe the word "specifies" is too
> strong, despite its appearance in a non-normative footnote."
> 
> So the  following expression
> 
> 2+3*5;
> is equal to 17.  For  human * has higher precedence than + so *
> operator will be first operated on 3*5 and then the resultant will be
> added to 2. So the result will be 2+(3*5) .
> 
> Then my question is how C compiler with out bothering about precedence
> produce the same result as 2+(3*5).
> 
> I tried to explain myself the outcome of 2+3*5  the way Chris Torek
> has explained the expression   -- - x  but I am not able to construes
> how the precedence of * will be enforced by the C grammar with out
> using operator precedence.

I can't do it either.
I use the precedence table in chapter 2 of K&R instead.

-- 
pete

Thread

Operator precedence. somenath <somenathpal@gmail.com> - 2012-05-06 20:10 -0700
  Re: Operator precedence. somenath <somenathpal@gmail.com> - 2012-05-06 20:23 -0700
  Re: Operator precedence. James Kuyper <jameskuyper@verizon.net> - 2012-05-06 23:57 -0400
  Re: Operator precedence. Kaz Kylheku <kaz@kylheku.com> - 2012-05-07 03:59 +0000
  Re: Operator precedence. pete <pfiland@mindspring.com> - 2012-05-07 05:48 -0400
    Re: Operator precedence. James Kuyper <jameskuyper@verizon.net> - 2012-05-07 07:52 -0400
      Re: Operator precedence. Ben Bacarisse <ben.usenet@bsb.me.uk> - 2012-05-07 13:18 +0100
        Re: Operator precedence. James Kuyper <jameskuyper@verizon.net> - 2012-05-07 09:08 -0400
          Re: Operator precedence. Ben Bacarisse <ben.usenet@bsb.me.uk> - 2012-05-07 14:36 +0100
            Re: Operator precedence. James Kuyper <jameskuyper@verizon.net> - 2012-05-07 13:29 -0400
      Re: Operator precedence. pete <pfiland@mindspring.com> - 2012-05-07 11:24 -0400
  Re: Operator precedence. "BartC" <bc@freeuk.com> - 2012-05-07 16:35 +0100
    Re: Operator precedence. jgk@panix.com (Joe keane) - 2012-05-10 19:05 +0000
      Re: Operator precedence. "BartC" <bc@freeuk.com> - 2012-05-10 20:35 +0100
        Re: Operator precedence. James Kuyper <jameskuyper@verizon.net> - 2012-05-11 09:25 -0400
          Re: Operator precedence. "BartC" <bc@freeuk.com> - 2012-05-11 16:42 +0100
            Re: Operator precedence. James Kuyper <jameskuyper@verizon.net> - 2012-05-11 12:28 -0400
              Re: Operator precedence. "BartC" <bc@freeuk.com> - 2012-05-11 18:42 +0100
                Re: Operator precedence. James Kuyper <jameskuyper@verizon.net> - 2012-05-11 15:18 -0400
                Re: Operator precedence. "BartC" <bc@freeuk.com> - 2012-05-11 22:52 +0100
                Re: Operator precedence. James Kuyper <jameskuyper@verizon.net> - 2012-05-11 18:39 -0400
                Re: Operator precedence. Ike Naar <ike@sverige.freeshell.org> - 2012-05-11 19:20 +0000
                Re: Operator precedence. Ike Naar <ike@sverige.freeshell.org> - 2012-05-11 19:28 +0000
                Re: Operator precedence. "BartC" <bc@freeuk.com> - 2012-05-11 22:28 +0100
                Re: Operator precedence. Ike Naar <ike@sverige.freeshell.org> - 2012-05-11 21:45 +0000
              Re: Operator precedence. Keith Thompson <kst-u@mib.org> - 2012-05-12 12:11 -0700
            Re: Operator precedence. Ben Bacarisse <ben.usenet@bsb.me.uk> - 2012-05-11 17:37 +0100
        Re: Operator precedence. Ben Bacarisse <ben.usenet@bsb.me.uk> - 2012-05-11 16:24 +0100
          Re: Operator precedence. "BartC" <bc@freeuk.com> - 2012-05-11 20:14 +0100
            Re: Operator precedence. Ben Bacarisse <ben.usenet@bsb.me.uk> - 2012-05-11 20:56 +0100
              Re: Operator precedence. "BartC" <bc@freeuk.com> - 2012-05-11 22:21 +0100
                Re: Operator precedence. Ben Bacarisse <ben.usenet@bsb.me.uk> - 2012-05-12 00:05 +0100
          Re: Operator precedence. jgk@panix.com (Joe keane) - 2012-05-11 22:46 +0000
            Re: Operator precedence. Ben Bacarisse <ben.usenet@bsb.me.uk> - 2012-05-12 00:17 +0100
              Re: Operator precedence. jgk@panix.com (Joe keane) - 2012-05-12 19:35 +0000
                Re: Operator precedence. "BartC" <bc@freeuk.com> - 2012-05-12 22:39 +0100
            Re: Operator precedence. Keith Thompson <kst-u@mib.org> - 2012-05-12 16:07 -0700
              Re: Operator precedence. jgk@panix.com (Joe keane) - 2012-05-13 19:08 +0000
                Re: Operator precedence. Keith Thompson <kst-u@mib.org> - 2012-05-13 13:17 -0700
                Re: Operator precedence. jgk@panix.com (Joe keane) - 2012-05-14 21:06 +0000
                Re: Operator precedence. Keith Thompson <kst-u@mib.org> - 2012-05-14 20:42 -0700
                Re: Operator precedence. Kaz Kylheku <kaz@kylheku.com> - 2012-05-13 23:20 +0000
      Re: Operator precedence. Keith Thompson <kst-u@mib.org> - 2012-05-10 15:24 -0700

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