Re: Precedence Rules for '$' and '^'

jamin.hanson@googlemail.com schrieb:
> Hi there,
>
> I am author of lexertl (http://www.benhanson.net/lexertl.html), a
> lexer generator library, and I have recently added support for '^' and
> '$'. As position matching in regex is not described in any books I
> have looked at, does anyone know what the precedence rules should be?


I think Perl regexes are what people expect, so I'd stick with the
precedences that PCRE uses.


> If an earlier rule starts with '$', does that mean that a subsequent
> rule starting with '^' has the '^' ignored?


I didn't understand that. A concrete example might help.


Regards,
Jo
[I don't understand it either. My understanding of typical REs is
that they special case ^ at the beginning of a pattern or chunk
that could match at the beginning, and $ at the end. -John]

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