The regex in the while works by removing all balanced pairs of parentheses, from the inside-out. Your code with the "print" should print 1111111 for both strings. The difference is that at the end, the first string will become 'aio' and the second will become 'aio)'. Something like: 
@foo = ('a(b(c)d(e(f)g)h)i(j(k)l(m)n)o',
        'a(b(c)d(e(f)g)h)i(j(k)l(m)n)o');

for (@foo) {
   print "\'$_\' has ";
   while s/[(][^()][)]//;        # get rid of matched ()
   print "un" if /[()]/;         # see if any unmatched
   print "balanced parentheses"
}

[download]
should work.

In reply to Re: getting a return code from a looping regular expression by BlaisePascal
in thread getting a return code from a looping regular expression by princepawn

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