Get yourself a copy of RFC 2822. (Don't forget to allow for obsolete addresses; not everyone has read this RFC yet.) If you have access to the O'Reilly book Mastering Regular Expressions, there's a regex in the back of the book that does an incomplete job of checking email addresses, but is about as close as you can get with a plain regex. (Be warned, it's 6598 characters.)

Why don't you want to use a module?

Update: If you want to do email verification by hand, the best advice I can give you is to study RFC 2822 thoroughly. You'll also find Text::Balanced useful for pulling apart the address.

--
The hell with paco, vote for Erudil!
:wq

In reply to Re: email check by FoxtrotUniform
in thread email check by mr2

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