The regex engine matches "leftmost longest" and not "longest leftmost". The non-greedy modifier changes "longest" to "shortest" but doesn't change "leftmost" nor make "leftmost" no longer trump "longest"/"shortest". ("leftmost" refers to how close to the start of the string is the beginning of the matched substring.)

The long match is indeed the leftmost possible match. The ? would change the quantifier so that you got the shortest of the leftmost possible matches instead of the longest of the leftmost possible matches.

You can read about sexeger (or search for more threads: sexeger sexeger) to see how sometimes it can be useful or at least fun to reverse your string and your regex so that you get the substring with the "rightmost" ending point and can choose between longest/shortest as the regex engine moves leftward (with respect to the original string).

For your particular case, I'd just use rindex and then substr.

- tye        

In reply to Re^2: Non-greedy regex behaves greedily (leftmost) by tye
in thread Non-greedy regex behaves greedily by fourmi

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