On Mon, 21 May 2001, Yukihiro Matsumoto wrote:
> |Please see the program listing in [ruby-talk:12558], and:
> |	1. Explain why that program works.
> Sorry, I don't get your point.  The code is:
> and because of "Foo.dup", it is not repeated inclusion.

You are perfectly right. I forgot about the .dup and the rest was just a
big hallucination.

> |Not only this piece of code does not find out whether there was already a
> |singleton class associated to that object... but, according to page 243 of
> |the Pickaxe book, this actually creates a singleton class for the object.
> |Which leaves this question doubly unanswered. 
> Oops...  singleton_methods do the job for most of the cases,
> unless you really want to know existance of empty singleton
> class, which usually can be ignored.

Such "empty" singleton classes could be ignored if it weren't for
foo.extend Bar, or class<<foo; include Bar; end, isn't it?

matju