On 2/14/06, Luke Palmer <[EMAIL PROTECTED]> wrote:
> On 2/14/06, David Romano <[EMAIL PROTECTED]> wrote:
> > I don't want to just skip <B> tags wholly, because they do serve a purpose,
> > but only in a particular context. (Can <?ws> be changed back to a "default"
> > if
> > changed to include html tags?)
>
> Brackets serve as a kind of scoping for modifiers. We're also
> considering that :ws take an argument telling it what to consider to
> be whitespeace. So you could do:
>
> rule Month :w {
> [ :w(&my_ws) J a n ] # not sure about the &
> # out here we still have the default :w
> }
Ahh, okay. So am I to understand that my_ws would just return a set of
individual characters or character sequences that would be considered
whitespace? Or would my_ws do something else?
> > Would something like below be easier to decode for a human reader?
> > text:without(<date>) {
> > ^ [.*] $
> > }
>
> Well, if you could define exactly what it means, then perhaps. Does
> that mean that date appears nowhere within the matched text, or that
> it just doesn't appear at the beginning. In either case, you can make
> these rules grammar friendly by including your test at the end:
>
> rule text_no_date {
> (.*)
> { $1 !~ /<date>/ }
> }
This is what I was thinking: nowhere within the matched text...hadn't
thought about the closure at the end.
> > If that adverb were available, then I could have a rule that doesn't include
> > two other rules:
> > line:without(<date>&&<name>) {
> > ^^ [.*] $$
> > }
> >
> >
> > The rule above would match a line with a <date> or <name>, but not a line
> > with
> > both.
>
> Huh. That kind of test really wants a closure. You can't use the
> regex & because that requires that they match at the same place. You
> can't use the logical &&, because <date> isn't an expression. Of
> course, that is unless you include your own parsing rule, but that
> isn't recommended.
I see. I guess I initally thought that it would be nice to have
important information like exclusions at the beginning, rather than at
the end, of a rule. Thanks again for the explanations and pointers.
David
