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From: "BartC" <bc@freeuk.com>
Newsgroups: comp.programming
Subject: Re: Pre And Post Increment Operator Output
Date: Fri, 22 Jun 2012 21:35:16 +0100
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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