From: "Ara.T.Howard" <Ara.T.Howard@...>
Date: 2004-02-14T08:24:55+09:00
Subject: inheritence of class vars


am i the only one suprised by this?

    ~/eg/ruby > cat class_vars.rb 

      class A
        class << self
          def x= value
            @@x = value 
          end
          def x
            @@x
          end
        end
      end
      class B < A; end

      A.x = 'forty-two'
      B.x = 42
      p A.x
      p B.x

      class A
        class << self
          def x= value
            @x = value 
          end
          def x
            @x
          end
        end
      end

      A.x = 'forty-two'
      B.x = 42
      p A.x
      p B.x


    ~/eg/ruby > ruby class_vars.rb 

      42
      42
      "forty-two"
      42

i see it, but don't believe it...  is it _correct_ to say that:

  iff you want a subclass to have it's own copy of a 'class var' - use instance vars

  * by 'class var' i mean _not_ an instance var.  obviously there are two
    types       

i don't know how i made it this long without that biting me, doh!

-a
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