A supplementary reply, this time in the form of a question.

I am trying to understand your third method that uses the recursive regular expression. What I think it is doing is finding balanced "01" pairs in the same way as the Camel book example finds balanced "()" pairs. What I want to know is, how does the regular expression know when to stop recursing? Is the "?" quantifier something to do with it? It seems to me that the regular expression is consuming characters from both ends of the string at the same time. Am I missing something obvious?

Cheers,

JohnGG

In reply to Re^2: A (non) reg-ex question by johngg
in thread A (non) reg-ex question by Ido

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