On Dec 20, 2011, at 12:26 PM, Khat Harr wrote:

> An instance variable is prefaced by @, where a class variable is 
> prefaced by @@.  Here's a small example:
> 
> class Thingy
>  @@thingies = 0
>  def initialize(name)
>    @my_name = name
>    @@thingies += 1
>    puts "A new thingy is here!"
>  end
> 
>  def whatsMyName
>    puts "This thingy is named '#{@my_name}'."
>  end
> 
>  def howMany?
>    puts "So far you have created #{@@thingies} thingies."
>  end
> end
> 
> The @@thingies class variable is shared by all instances of the class. 
> Changing that variable in any one of the classes will change it for all 
> of them.
> 
> Is this what you were looking for?

I think he is  looking for class instance variables.

class Foo
  @class_ivar = 3

  def self.class_ivar() @class_ivar; end

  def bar(a)
    puts "#{a} + #{self.class.class_ivar} = #{a + self.class.class_ivar}"
  end
end

foo = Foo.new
foo.bar(6) # 6 + 3 = 9

cr