There are no hard and fast rules for helper methods. The minimilists would say you shouldn't have any at all, but Perl is not a minimilistic language.

That doesn't mean you need to go overboard with writing helper methods. The only guideline is: implement the ones you expect to be used a lot. You often won't know what will be used a lot until you actually use the module, so there is no sense spending too much time on helper methods in the first version of the module.

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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