in reply to Determining if you have balanced delimiters

Your ARRRGH is correct. I believe your code will incorrectly pass the string "(()" because the second "(" qualifies for "." in the middle.

What you need is a dot that doesn't match any of your other items of interest. Perhaps (untested): 

$middle = "(?:(?!$left|$right|$escape$left|$escape$right).)";

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-- Randal L. Schwartz, Perl hacker

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Re (tilly) 2: Determining if you have balanced delimiters
by tilly (Archbishop) on Nov 21, 2000 at 17:58 UTC
    No, it works. It was supposed to do that. :-)

    The idea is that it repeatedly matches a pair and removes it while it can. When it is done, it then checks if any were left over.

[reply]
      Well, in that case, it's another problem, since the dot can match the escape character, so it'll incorrectly blast "(\)".

      I knew it was something. {grin}

      -- Randal L. Schwartz, Perl hacker

[reply]
        Did you test it?

        It recognizes "(\)" as unbalanced. OTOH he *didn't* bother to have an escape escape an escape. So "(\\)" is still unbalanced.

        But that could be a question of definition, not a bug.

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