"it is surprising how a glass of Italian Chardonnay can do good to the brain cells"

But it is far from surprising that providing a clear specification of what you seek will enhance the liklihood that the Monks will provide useful advice.

I mention this because your original post. The first bit of code, [/^(BAR|BAZ)$/, requires that /BA[RZ]/ NOT be the last element of your string, while the second, the negative lookahead, (?!(BAR|BAZ)).*$/, allows anything NOT /BA[RZ]/ followed by (your dot_deathstar, .* any number of any characters INCLUDING /BA[RZ]/.

Judging by other replies, I wasn't the only one confounded thereby. yet very shortly after your clarifying example (in this node's parent) you got a reasonably general answer from Anonymonk (and re that answer, I'm not sure I buy the advice to "avoid as the plague the use of capturing groups in the decomposed regexes..." but the thought process outlined in that node deserves a ++ ((and got same from me)).

In reply to Re^4: Zero-width look-ahead regexp question by ww
in thread Zero-width look-ahead regexp question by rovf

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