First, watch out for the 'dot' in your set, which Perl interprets as "stuff" (i.e. not a linefeed ('\n'), unless you're using crazy regexp options like /s). You probably mean literal-dot ('\.') instead.

Secondly, I'm not sure why you're using a negative match assertion ('!~') instead of a positive one ('=~'). It seems to be the opposite of what you're looking for:      if ($entry =~ /^([a-zA-Z0-9\@_\.]*)$/) { This code memorizes the entire e-mail address, which is apparently what you intended by using the brackets in your regexp. As a note, though, since you are memorizing the entire thing, why bother to do this instead of just using $entry?

Note: On the subject of e-mail address matching regexps, you will have to be more open-minded about what can appear in these. For example, many characters other than the ones you specified are actually valid in the e-mail address part of the name. I would modify it so that the checks on the e-mail address part are more liberal, and further, that instead of using the star operator (0 or more), which has the unfortunate effect of validating a zero-length string(!), that I would demand at least one character on each side.     if ($entry =~ /^([a-zA-Z0-9_\.\-\!\%\#]+\@[a-zA-Z0-9_\.]+)$/) { Here's some e-mail addresses which could be used to test any modifications: 
 qw [
      abc@123.it
      a@b
      tech-support@super.net
      user_144@z.com
      webmaster@estherdyson.museum
 ];

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Tip: It is probably a good practice to "escape" all non-alphanumeric characters in your regexps until you know which ones are safe. As you found out, a seemingly inert '@' was interpreted otherwise, and the unassuming '.' means a whole lot more than just dot inside a regexp.

In reply to Re: @ in regex, or not? by tadman
in thread @ in regex, or not? by JPaul

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