Let's say I have this regex: m/foo(.*?)foo/; What I'm looking to express that I don't know how to is this: how do I make it so that $1 may not contain the substring "bar"? I've looked into ^b^a^r and ^bar both of which are wrong because they either require the string to be at least 3 characters long, don't account for different posiitons of bar within the string, or also disallow "rab" and "arb". So I want to express minimal matching of any arbitrary characters disallowing a certain subpattern. How can I do this? I've heard as a suggestion negative lookahead assertions, but I was under the impression that they were only for matching overlapping pieces of text, i.e. if you were matching: "pop" against "popop" you would use a negative lookahead assertion if you wanted more than one match to be returned. (because the first p of the second "pop" overlaps with the last p of the first match) Any suggestions?

In reply to Regex'ing backreferences by Uruk

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