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How long has it been that regexes have returned anything predictable from non-matching parenthesis within regexes that match?

With a regex like /A(.)?B/, perl used to fill $1 with whatever the last attempt at a match was, and so the result was not undefined, but unpredictable. So on a string like 'AB', you'd end up with 'B' in $1, and although it might be non-intuitive, it was actually conceptually correct, because the string does match /A(B)?B/, and it was up to the programmer to use something more sensible, like </code>/A((.)?)B/</code>, and only depend on the inner parenthesis if the outer ones contain something besides the empty string.

But now I guess perl just does (or will do) the right thing :)


In reply to Being intuitive, conceptually correct, and just doing the right thing by runrig
in thread Being pretentious, and getting away with it. by japhy

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