fix ruby variables

lib/vool/ivar_assignment.rb

@@ -0,0 +1,12 @@
+module Vool
+
+  class IvarAssignment < Assignment
+
+    def to_mom( compiler )
+      to = Mom::SlotDefinition.new(:message ,[ :receiver , @name])
+      from = @value.slot_definition(compiler)
+      return chain_assign( Mom::SlotLoad.new(to,from) , compiler)
+    end
+
+  end
+end