Re: Argh! Regular expressions in Lua

[Gavin Wraith <gavin@...>]

In message <ek2212$mj6$1@sea.gmane.org> you wrote:


> I might, as the subject interest me, but it would be a waste of time if:
> - Roberto already tried and concluded it is too costly. I doubt being 
> able to do better...

Same here.

Also I am guilty of not paying enough attention to the interaction
between captures and alternation. Alternations within a capture, OK,
but captures within an alternation present a problem. With < ... >
as notation for a capture, and {...} for a pattern variable,
what would

   "{x}|<{y}>"

mean? If y is a subpattern of x, e.g.

    "fool|<foo>"

what then? Simply bunging in a capture syntax to the full Kleene syntax
does not make very much sense. At least with the Lua syntax positions
inside the pattern correspond to positions inside the string. That is
broken by the alternation operation.

-- 
Gavin Wraith (gavin@wra1th.plus.com)
Home page: http://www.wra1th.plus.com/