As numerous people have mentioned, the Komodo IDE includes a regex debugger based on mark-jason dominus's backend. I'd like to toot my own horn and point out a purl perl alternative:

ReBug: A regular expression debugger in perl...I gave a talk on it at TPC5. The paper, and the application can be found here:

http://perl.jall.org/rebug/

In reply to Re: Regular Expression GUI? by Mongo
in thread Regular Expression GUI? by major tom

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