From: timr <timrandg@...>
Date: 2010-11-12T11:05:21+09:00
Subject: Re: what's an object?

On Nov 11, 12:59 am, Ammar Ali <ammarabu...@gmail.com> wrote:
> On Thu, Nov 11, 2010 at 10:51 AM, Brian Candler <b.cand...@pobox.com> wrote:
> > One other point. A local variable is not an object and never is -
>
> I think that's too general and confusing, at least to me.
>
> >> def m
> >>   a = [1,2,3]
> >>   p a.is_a?(Object)
> >>   end
> => nil
> >> m
>
> true
> => true
>
> Is there more insight behind that statement? Or am I missing something
> fundamental?
>
> Thanks,
> Ammar

Hi Ammar,
I do think the code means something different than you are
interpreting it to mean.

obj.is_a?(Object) asks if Object is listed in the ancestors of obj. It
is another way of saying obj.class.ancestors.include?(Object)

Everything you can send a message to in ruby is a descendent of
Object, so it will always be true, er, I predict. However, when you
ask a local variable (which is really a pointer to, in your case, an
instance of Array) you are asking is Object listed in the ancestors of
the Array class? It doesn't ask if a variable considers itself an
instantiated object.
Tim