From: Arlen Christian Mart Cuss <celtic@...>
Date: 2007-08-17T00:17:55+09:00
Subject: Re: Subject: What *exactly* does an instance variable in the top	level do / mean?


On Fri, 2007-08-17 at 00:09 +0900, Pito Salas wrote:
> Here's an example:
> 
> ---------------
> @tl_instance = "hello ruby"
> puts @tl_instance
> 
> def tl_method
>    puts "from tl_method -- @tl_instance: #{@tl_instance}"
> end
> 
> tl_method
> 
> class Tl_class
>    def tlc_method
>      puts "from tlc_method -- @tl_instance: #{@tl_instance}"
>    end
> end
> 
> Tl_class.new.tlc_method
> ------------
> 
> In tlc_method, I am unable to access @tl_instance. Presumably because
> it's an instance variable in some other class not Tl_class. But who's
> instance variable is it? Kernel? If so, how do I access it?

celtic@sohma:~$ ruby
puts "Self is #{self}"
puts "Self is of #{self.class}"
@i = 32
puts self.instance_variable_get('@i')
puts instance_variable_get('@i')
Self is main
Self is of Object
32
32
celtic@sohma:~$ 

You get the same results if you enter these in irb. The scope is an
Object called `main', and all instance variables belong to it -- not,
say, a class like Kernel.

Cheers,
  Arlen.