Tom writes:
> I'm not sure whether C does so, but I believe that Perl does NOT
> promise that auto-increments will be executed in the "expected"
> left-to-right order. Thus, if a single expression includes more than
> one auto-increment working on the same variable, generally you can't
> be sure what Perl will do with it. As you found.
In the C standard, the behaviour for
int a = 1, b;
b = ++a + a++;
is *undefined*.
Perfectly standards-compliant C compilers can perform any of the
following actions with equal validity:
* the compiler can dump core, and produce no output.
* at run time, the program can halt printing "Do not be a loser!"
* it can return "42"
* it can return '2' (1 + 1) and then increment a twice.
* it can - through blind stupid luck - return 5
See the comp.lang.c faq Questions 3.2 et seq. and comp.lang.c faq
question 11.33
Short answer: In C, Don't Do That. By extension, don't do it in Perl.
-- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
Lawrence Statton - [EMAIL PROTECTED] s/aba/c/g
Computer software consists of only two components: ones and
zeros, in roughly equal proportions. All that is required is to
sort them into the correct order.
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