Re: Pre And Post Increment Operator Output

From	"BartC" <bc@freeuk.com>
Newsgroups	comp.programming
Subject	Re: Pre And Post Increment Operator Output
Date	2012-06-22 21:35 +0100
Organization	A noiseless patient Spider
Message-ID	<js2l17$cd9$1@dont-email.me> (permalink)
References	<8404c4f1-a3b7-46b7-ad9c-17de265f9aee@googlegroups.com><js02hp$jsl$1@dont-email.me> <js03uf$sb3$1@dont-email.me><js092m$pov$1@dont-email.me> <lnipek8bri.fsf@nuthaus.mib.org><js1gf5$l7v$1@dont-email.me><0.06d3eacd14619c86d384.20120622143458BST.87ehp7o4fx.fsf@bsb.me.uk><js21jb$963$1@dont-email.me><7MudnTZhnIs6EnnSnZ2dnUVZ_qCdnZ2d@earthlink.com><js27pl$h7c$1@dont-email.me> <0.0b3aeb4b00dfdccbd115.20120622205336BST.87395nnmwv.fsf@bsb.me.uk>

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"Ben Bacarisse" <ben.usenet@bsb.me.uk> wrote in message
news:0.0b3aeb4b00dfdccbd115.20120622205336BST.87395nnmwv.fsf@bsb.me.uk...
> "BartC" <bc@freeuk.com> writes:
>> "Patricia Shanahan" <pats@acm.org> wrote in message
>>> On 6/22/2012 8:02 AM, BartC wrote:

>>>> result of i=(++i)+(++i)+(++i), when i starts at 0

>>> In Java, i does have a specified resulting value. The effect will be the
>>> same as i=3*i+6.
>>
>> So it ends up with i=6, when i starts at zero. The case for '6' is
>> improving..
>
> The case for 6 in Java is rock-solid.
>
> <snip>
>> I suggested in comp.lang.c that the result of the above ought to be 6,
>> in line with the original poster's expectations, (before going on to
>> explain why it might not be in C), for which I was castigated and even
>> called evil.
>
> Way to go BartC.

Maybe the OP in the original thread had a Java background. Or maybe he just
decided the common-sense result was 6, and wanted to know why C didn't
agree.

But I give up; you win. Clearly if someone sees such an expression, even
before they go anywhere near an actual programming language, they have to
assume that *expecting* a result such as 94613277, is just as plausible as
expecting it to be as 6.

(BTW how did Java, a C derivative, end up with well-defined semantics for
this kind of expression? And why isn't the result 94613227, but... 6? Why
choose 6? Because, after all, you guys keep telling me that i = 
(++i)+(++i)+(++i) is completely meaningless. Or is it conceivable that 6 
does, after all, actually make more sense than 94613277..)

Anyway, I'll leave you guys to it.

-- 
Bartc

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Thread

Re: Pre And Post Increment Operator Output "BartC" <bc@freeuk.com> - 2012-06-22 16:02 +0100
  Re: Pre And Post Increment Operator Output Patricia Shanahan <pats@acm.org> - 2012-06-22 08:30 -0700
    Re: Pre And Post Increment Operator Output "BartC" <bc@freeuk.com> - 2012-06-22 17:49 +0100
      Re: Pre And Post Increment Operator Output Patricia Shanahan <pats@acm.org> - 2012-06-22 10:36 -0700
        Re: Pre And Post Increment Operator Output "Chris Uppal" <chris.uppal@metagnostic.REMOVE-THIS.org> - 2012-06-23 09:57 +0100
      Re: Pre And Post Increment Operator Output Ben Bacarisse <ben.usenet@bsb.me.uk> - 2012-06-22 20:53 +0100
        Re: Pre And Post Increment Operator Output "BartC" <bc@freeuk.com> - 2012-06-22 21:35 +0100
          Re: Pre And Post Increment Operator Output Ben Bacarisse <ben.usenet@bsb.me.uk> - 2012-06-22 23:19 +0100
            Re: Pre And Post Increment Operator Output "BartC" <bc@freeuk.com> - 2012-06-23 01:15 +0100
  Re: Pre And Post Increment Operator Output Ben Bacarisse <ben.usenet@bsb.me.uk> - 2012-06-22 17:44 +0100

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