I think David's on to something good here. A major problem with
holding the bracket-matching possibilities in a special variable
(or a pair of them) is that one can't figure out what the RE is
going to do just by looking at it -- you have to look elsewhere.
Nathan Wiger wrote:
>I think it's cool too, I don't like the @^g and ^@G either. But I worry
>about the double-meaning of the []'s in your solution, and the fact that
>these:
>
> /\m[...]...\M/;
> /\d[...]...\D/;
>
>Will work so differently.
Yes. Things that look similar should act similar. Things that act
differently should look different.
>But, how about a new ?m operator?
>
> /(?m<<|[).*?(?M>>|])/;
>
>Then the ?M matches pairs with the previous ?m, if there was one that
>was matched. The | character separates or'ed sets consistent with other
>regex patterns.
Ah, this is a neat idea!
Unfortunately, as Richard Proctor pointed out, ?m is taken. Perhaps
(?[list|of|openers) and (?]list|of|closers) ?
Does that look too bizarre, with the lone square bracket in each?
Or does that serve to make it mnemonic (which is my intention)?
And --- can-of-worms time --- we're only intending the list elements
to be constant characters, but that syntax *looks* like it can take a
regular expression for any of the list elements, so people are going
to try to do that someday. I cannot imagine what someone would want
do use a regexp in such a construct, but abuses of the language are
not limited to *my* imagination :-)
(?[list|of|openers) would match any expression in the alternation
list. Subsequently, (?]list|of|closers) would match the *corresponding*
expression, but would keep track of the nesting level of the originally-
matching open-bracket expression.
Sound about right?
----------------------------------------------------------------------
Eric J. Roode, [EMAIL PROTECTED] print scalar reverse sort
Senior Software Engineer 'tona ', 'reh', 'ekca', 'lre',
Myxa Corporation '.r', 'h ', 'uj', 'p ', 'ts';
