Re: MSIE integer overflows

>Not true: "++i" will increase i first and return the result of that

Yes, of course.

Again, I'm talking about C here, simply because I don't know JS to this level of detail. But...

document.write((i==++i) + ' ' + (i==++i) + '<BR>');

Seems like ambiguous code that might rely on unspecified behaviours. Postincrement and preincrement are gotchas in C. For example the following code:

i = 2;
printf ("%d", i++ * i++);

Often does not print 6 as you might think, but rather prints 4. The reason is that the postincrement operator increments the values before the next sequence point, not necessarily the next _operation_.

I was just pointing out that using expressions like i == ++i seems a bit suspect. I'm not certain, but I believe a C compiler is free to do both increments prior to the rest of the expression. It does seem like it should always be a tautology, though.

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Do you get the same results if you write the same code less ambiguously?

Cheers,
~ol Received on Wed May 14 18:38:22 2003