From: "Eric D." <p57mafuvev6oldk@...>
Date: 2006-02-01T04:29:45+09:00
Subject: question about class variables and instance variables

Hello,

I've some difficolties with instance variables and classe variables

With :

   class A
       def foo
          @foo
       end
       def bar
          @@bar
       end
    end

    a = A.new

---------                  ------------                  ------------
|       |                  |          |                  |          |  
|  a    |--(instance_of)->-|    A     |--(instance_of)->-|  Class   |
|       |                  |          |                  |          |
---------                  ------------                  ------------

a is an instance of A which itself is an instance of Class
@foo is an instance variable, so it is stored in box "a"
@@bar is a class variable, so it is stored in box "A"


if I do something like the following :

   class A
      def A.strange
         @strange
      end
   end

Where is stored my @strange ? I had the hypothesis that @strange in the 
"A" context was equivalent to @@strange in the "a" context but the 
following code prove me to be wrong :

  class A
      def A.strange
         @strange
      end
      def strange=( val )
         @@strange = val
      end
  end

  a = A.new
  a.strange= 2
  p A.strange # output is nil, not 2


Could someone explain me where to place this @strange ? in which box 
could I store it ?




Thanks in advance
--
Eric D.

-- 
Posted via http://www.ruby-forum.com/.