Thanks for your answer, the thing I don't understand is how it makes the difference when the engine fails. In both cases, the match occurred. In the first case,how is it possible that it doesn't try to match ABC again? After all, it matched once, failed and thus gets another chance to match exactly 3 characters at the position it failed.

Is it different because \w{2,}? has a sort of counter that remembers how long was the last attempt? And so it extends the match when it tries to run again because matching a longer chain is seen as a "new match that didn't occur here before"?

In reply to Re^2: regex backtracking question by aeqr
in thread regex backtracking question by aeqr

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