[chuck-dev] for loop, empty conditional statement, possible fix

[Kassen]

Szilveszter


> I would not go scientific here... :) I just wrote down a line of code which
> I expected to work... However, I've  never written down anything like:
>
> if() {} or while() {}
>
> Erm, no. :-)


> which I suspect would give a C compiler error.
>
> I should hope so, yes. If I were a parser I'd go on strike over that.


> My point is that the first and the third part of the for() statement can be
> omitted as for now (in ChucK). So I don't see a point why the second one
> shouldn't work the same way.


The one perspective I could see is that the first and third are actions, and
omiting those seems quite natural if we need no action to be taken. The
second is a condition and it's less intuitively clear what omiting it should
mean. Borrowing from C seems quite natural.

I seem to remember there were previous issues with more exotic "for" loops
in ChucK, btw. Previously there was a issue with stuffing more than one
thing (some of which could be commands that need not evaluate to true or
false, as long as the last one did), that would also crash. My memory is
hazy on this as I didn't see the use but now I do, it's probably to get
those out of the scope of any "continue" commands we might use.

Most important to me is that I don't think that anything that comes through
the parser should crash the whole VM. To be perfectly clear; I don't
disagree with anything here, I'm just trying to see whether this is or
should be part of a larger structure that I should understand. I know I can
sometimes come across like I'm arguing when doing that. I think that urge is
satisfied for now :-).

Thanks again,
Kas.
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