There's this (not-too-daft) idea going around that the user of a module shouldn't have to "consciously" garbage-collect instances - they should just collapse when the instance reference goes out of scope. But in this example that clearly won't work, so if there's no other way, a DESTROY method is going to be necessary.

But I would try to make the class autodestructible from the outset if at all possible - having to DESTROY is certainly going to confuse some people.