I suspect that pg meant to say "should not be exposed BY the class that holds the collection." Then it makes perfect sense.

This was a very nice reminder for me, anyway, of the usefulness of OOP in certain cases. Although I enjoy the freedom, speed, and flexibility of Perl, it doesn't mean that we should not use a little more structure when it's beneficial to do so.

I must admit that OOP is a weakness of mine, but I am diligently working to improve in that area.

pg's meditation was timely for me. Your question helped expose the crux of pg's point. That's why I'm voting for both of your nodes.