Hmmmmm...maybe you are right. !=~ could be an issue, depending on what has most priority, =~ or !=. If it is the latter, then what the regex effectively says is, if it is not equal to $target_name in reverse...~ by itself (addressing a non-numeric string)returns a string with identical length but with all the bits of the string complemented. I don't know if that effect is changed by the presence of // though... Could I be facing a double negation? If it is the former, then I would assume it would be the rough equivalent of !~.