Ruby code:

    # Allows access to the object attributes, which are held in the <tt>@attributes</tt> hash, as though they
    # were first-class methods. So a Person class with a name attribute can use Person#name and
    # Person#name= and never directly use the attributes hash -- except for multiple assigns with
    # ActiveRecord#attributes=. A Milestone class can also ask Milestone#completed? to test that
    # the completed attribute is not +nil+ or 0.
    #
    # It's also possible to instantiate related objects, so a Client class belonging to the clients
    # table with a +master_id+ foreign key can instantiate master through Client#master.
    def method_missing(method_id, *args, &block)
      method_name = method_id.to_s

      if self.class.private_method_defined?(method_name)
        raise NoMethodError.new("Attempt to call private method", method_name, args)
      end

      # If we haven't generated any methods yet, generate them, then
      # see if we've created the method we're looking for.
      if !self.class.generated_methods?
        self.class.define_attribute_methods
        if self.class.generated_methods.include?(method_name)
          return self.send(method_id, *args, &block)
        end
      end
      
      if self.class.primary_key.to_s == method_name
        id
      elsif md = self.class.match_attribute_method?(method_name)
        attribute_name, method_type = md.pre_match, md.to_s
        if @attributes.include?(attribute_name)
          __send__("attribute#{method_type}", attribute_name, *args, &block)
        else
          super
        end
      elsif @attributes.include?(method_name)
        read_attribute(method_name)
      else
        super
      end
    end