"Gavin Sinclair" <gsinclair / soyabean.com.au> wrote in message
news:038401c25b30$0bb7ade0$c32386cb / nosedog...
> I suppose that most math calculations would be isolated to a couple of classes.
> These could all "include Math", thus simplifying the call.
>
> Is this good style?  Is it the Ruby way?  Is there any performance hit by

Well it is very reasonable (I personally I try to avoid this
as much as possible, probably without good reason)
You will eventually get some performance  degradation if
the including module contains a looot of (private)
instance_methods ...

> including the same module in two classes?

- there is almost none I  believe ...

>
> BTW my question remains unanswered.  Christoph mentioned namespaces as if they
> were different from modules, and I don't know what he was talking about.

Yes they would be different (Ruby does not have them yet?)
- for one  thing you cannot uninclude modules - something
I definitely would expect from namespaces.

Anyway I am a bit lost what Ruby namespace are
supposed to be in detail - Matz himself was talking them
without providing the latter, leaving plenty of room for
useful(less?) speculations.
Keiju Ishitsuka's  ``scope_in_state'' pure Ruby extension
fills this gap but I am not sure if this module matches Matz
expectations  (nor mine;-) .

/Christoph