From: Robert Klemme <bob.news@...>
Date: 2004-06-22T17:08:12+09:00
Subject: Re: A question about Class and Object


"Sam Sungshik Kong" <ssk@chol.nospam.net> schrieb im Newsbeitrag
news:paHBc.6843$_e1.3669@newssvr27.news.prodigy.com...
> Hello!
>
> I found a strange thing.
>
> Object.class
> =>Class
> Class.class
> =>Class
>
> As you see, Object and Class are of same type.
>
> Object.methods.length
> =>73
> Class.methods.length
> =>74
> Class.methods - Object.methods
> =>["nesting"]
>
> I expected that Object has same methods as Class but it's not.
> Can somebody explain and teach me please?

There is also a general answer in Ruby: even if two instances belong to
the same class they need not have the same number of methods, because
methods can be defined on a per instance basis.  Consider:

irb(main):015:0> class Foo; def test; "test"; end; end
=> nil
irb(main):016:0> f1 = Foo.new
=> #<Foo:0x1016f920>
irb(main):017:0> f2 = Foo.new
=> #<Foo:0x1016c788>
irb(main):018:0> class << f2; def test2; "test2"; end; end
=> nil
irb(main):019:0> f1.class
=> Foo
irb(main):020:0> f2.class
=> Foo
irb(main):021:0> f1.methods.grep(/test/)
=> ["test"]
irb(main):022:0> f2.methods.grep(/test/)
=> ["test2", "test"]
irb(main):023:0> f2.methods - f1.methods
=> ["test2"]

Regards

    robert