Actually, after thinking about it, I don't think a symbolic ref solution would be so bad in this case, provided you take a few percautions. At the top of your subroutine, make sure $matchnum matches against /\A\d+\z/ and that $$matchnum is a defined value after the match (change your last line to $result = $$matchnum if $$matchnum;).

Though overall, you're still probably better off with the array solution.

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I wanted to explore how Perl's closures can be manipulated, and ended up creating an object system by accident.
-- Schemer

Note: All code is untested, unless otherwise stated