I would suggest Regexp::Common:

use warnings;
use strict;
use Data::Dump;
use Regexp::Common qw/balanced/;

"(a a (a a)(a a))(b b(b)b b)" =~ /$RE{balanced}{-parens=>'()'}/;

dd $&, $';  # ("(a a (a a)(a a))", "(b b(b)b b)")

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Though of course there are plenty of other solutions, including Parse::RecDescent, though that might be a little overkill if this is all you're doing. See e.g. regex for nested "<"/">', and note that Text::Balanced is a core module.

In reply to Re: Matching nested parens by haukex
in thread Matching nested parens by BernieC

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