From: Paul Lutus <nospam@...>
Date: 2006-11-13T17:10:05+09:00
Subject: Re: regular expression too big

Peter Schrammel wrote:

>> When you post an question like this, it is always a good idea to
> reveal the
>> purpose as well as the method.
>> 
>>
> 
> First of all: Thanks for the replies, I think I have enough input to
> chew on.
> 
> And to reveal the purpose:
> I'd like to match a LOT of words/strings (words with spaces) and
> sometimes regexes against a lot of small and medium size( < 10000 byte )
> strings.

If you are going to compare strings to strings as well as strings to
regexes, maybe a two-tiered scheme would be better. First tier, simple
textual comparison using a hash of strings. Second tier, regexes.

This removes the ambiguity that a particular data string might pass a string
comparison but fail any of the provided regexes, or the opposite. It will
also be much faster than a gigantic list of strings and regexes, all
presented to the regex engine as though they were all regular expressions,
even though some are simple string comparisons.

I think this (e.g speed improvement) would have been true in Perl also.

-- 
Paul Lutus
http://www.arachnoid.com