Subclassing built-in types

[Emiliano Molina]

Emiliano Molina wrote:
--- some stuff I was confused about ---
> Where can I find that documentation?  I've looked through the manual but 
> can't find anything relevant.  Google searches bring up articles that 
> talk about code as described in my first example but I can't find 
> anything like the second.

I received no answers to my post (not complaining) and I am curious as 
to wether it was a silly question or if there was no answer because what 
I wanted to know is not documented.

Thanks for your replies (if there are going to be any!)