On Fri, 11 May 2001 08:29:07 -0500, Tad McClellan wrote:
>On Thu, May 10, 2001 at 04:26:56PM -0700, Daniel S. Wilkerson wrote:
>
>> Flex - Put all of flex right into Perl.
>Don't we already have that in Perl 5?
Sortof.
What he is proposing, is again the age old proposal of putting the
notion of (simple) grammars into Perl's regex engine.
Part of what he proposes, namely the events, can/could be done with
embedded perl code into the regex, AKA the infamous "(?{...})"
construct. The advantage over doing this in plain perl, as you showed,
is that includes the possibility for backtracking, all without any help
from the outside.
The "(??{...})" construct might likely be used to match nested
parentheses, for example. I'm not really sure, I'm not too familiar with
this crash-prone feature.
--
Bart.
