Perl's regular expressions already have a lot of optimizations in them. But if you are interested, have some time, and want to put in some serious thought, here is a link to an interesting discussion.

Don't mean to toot my horn, my post is just a good entry point into a discussion involving a lot of interesting things.

There were a few other good discussions in the same timeframe if you are willing to go look for them.

In reply to RE (tilly) 1: Regular Expression Optimizer by tilly
in thread Regular Expression Optimizer by PsychoSpunk

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