I can only refer you to the article that MeowChow mentioned. Taking a look at Tom Christiansen's list of benefits that someone who rolls their own RE usually misses, you get zero out of 3 of them.

RE's are not always the right answer...

UPDATE
Changed the link because the page moved. (Thanks footpad.)

In reply to Re (tilly) 2: Validating Numbers in CGI Script? by tilly
in thread Validating Numbers in CGI Script? by footpad

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