Re^3: check if string contains anything other than alphanumeric

[FunkyMonk]

If a character class starts with ^, it is a negated character class. That is, it will match any character that is not in the class. So, /[^a-zA-Z0-9]/ will match any character that is not a letter or digit.

See perlretut for a tutorial on regexps and perlre for the details.

update: My 200^th node :)