# having dealt with edge cases check for the valid chars
return 0 unless m/^[A-Za-z0-9\.\-]+\z/;
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Depending on the reason for testing the input, you may want to allow underscores in there so that things like dear_raed.blogspot.com get through — that's technically invalid but is in use; it works for me at home but not in the office.

Smylers