Front page | perl.perl5.porters |
Postings from August 2010
karl williamson wrote:
>Here's my reasoning for excluding from consideration most of these. I've
>scanned the tokenizer code, and there appear to be heuristics to decide
>if something is an interpolated variable, the end of the pattern, and the
>boundaries of character classes. So it seems a lot less dangerous to
>exclude $ % @ ; [ ]
$ % @ I agree with.
Why do you include semicolon? I don't see a problem with it.
Brackets I think should be OK here if they're used in a paired way.
So not suitable for our current job, but potentially available for
something else.
> Also, quotes as you said, " ' `
>And, since / is the common regex delimiter, excluding it seems like a
>good idea for human confusability issues,
I'd exclude / here, because we've got to leave some character that's
always available as a delimiter, and since / is the standard delimiter
I'd pick that one. But " ' ` are *not* commonly quote characters for
regexps, so I don't think it's necessary to exclude them. Indeed,
' is already used as a metacharacter in (?'NAME'pattern).
> as well as anything that is a
>paired delimiter, so } is out.
Yes, save that for paired usage. {} pairs are already used in several
parts of regexp syntax, and I wouldn't want to use either of them in
any other way. Both for mnemonic reasons and to avoid screwing up {}
quoting of regexps.
> Similar concerns get rid of \
Yes.
> I'd
>rather keep _ in reserve as it is a word character,
I was thinking _ would be a fairly good choice for our current use.
The spacer uses you suggest, or at least some of them, would probably be
better served by space characters and /x. But I don't object to keeping
our hands off _ for now.
>I'd rather not use ^, again for human usability issues, as that often is
>the first thing in a pattern.
I don't see a problem with (?^...) meaning something that has nothing
to do with the ^ anchor.
> A comma doesn't seem to me to convey the
>right meaning,
Agreed. Would be fine for some other use.
> I didn't want to use tilde
>because of the visual confusability with -,
As previously noted, I disagree with this being a problem.
> and not * because of a
>number of things that start like (*PRUNE),
I don't think that should stop us. (?*...) is quite distinct from (*...).
> so that left the period.
Period is fine.
For our present purpose, I'd be happy with any of
_ ^ ~ * .
-zefram
Thread Previous
|
Thread Next