Ah, fantastic, hadn't even thought of using grep. Thanks very much, rather an embarrassing first post. No, there wasn't any special need for Regexp other than trying to learn a bit more about them. My code now looks like this and works:

#@words is a bunch of words , $line is the line to search

if(!grep{$line !~ $_} @words) {
#success
}
[download]

(I didn't actually need the missing ones.) Thanks a lot, imp!