Since the monastary was so helpful with my last question, here's a followup/further question. I was trying to implement the 
(??{CODE})

[download]
sequence for a matching regexp to match a string with balanced braces using this recursion regexp: 
$np = qr{
          \{
          (?:
             (?> [^{}]+ )
           |
             (??{ $np })
          )*
          \}
        }x;

[download]
It turned out the problem I had was that I was using an old version of perl that didn't support the delayed interpolation sequence. So no problem, I upgraded and all is fine and dandy etc. But here's my question: Lets say that the sequence didn't exist, or that I'm using perl circa Billy Idol or something. I know that without this newer form of perl recursion a standard regex wouldn't be able to make this type of nested brace match(or so I've been told by coders more knowledgable than I). So my thinking went like this: When I finally decided I needed some monk advice for my previous problem, I had already invested a lot of time and energy into what I had hoped would be a handy and useful program. How could I have at least come close to the function of the newer sequence without using it? By this I mean, if I was unable to use the delayed interpolation sequence and had to replace the regex with some "old fashioned" code, what would my options be? I was very worried about this problem until my salvation yesterday, now its only a "what if" question for people who are in the know. Don't worry, everything is working fine :-) I was just wondering what, say, the author of the recdescent module did to achieve similar effect back in the dark ages.

In reply to Balancing braces without (??{}) by tshabet

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