From: "David A. Black" <dblack@...>
Date: 2008-10-17T19:40:28+09:00
Subject: Re: help on inheritance and class methods pls?

Hi --

On Fri, 17 Oct 2008, Barbara Mcinnes wrote:

> Hi there,
>
> Hoping someone explain this to me as I'd like to understand it properly.
> I've been reading about Ruby's metaclasses, but I don't get this:
>
> class Test
>   def foo
>     puts "in foo"
>   end
> end
> => nil
>
> class Test2 < Test
>  def self.bar
>    foo
>  end
>  def method_missing(name, *args)
>    puts "in method_missing"
>  end
> end
> => nil
>
>> Test2.new.bar
> in method_missing
> => nil
>> Test2.new.foo
> in foo
> => nil
>
> why does invoking method bar on the instance find class Test2's
> method_missing instance method, but not instance method foo inherited
> from class Test?

You've got a class method Test2.bar, but you never call it. (The
program would run the same if you deleted that method.) When you send
the message 'bar' to your instance of Test2, it hits method_missing
because there's no instance method bar in Test2 or any of its
ancestors.


David

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