inc.rb

class ActiveRecord::Base
  def self.incorporates(association_id, options = {})
    has_one(association_id)
    id = association_id.to_s
    klass = id.camelize.constantize
    obj = klass.new
    obj.attributes.each do |att|
      send :define_method, "#{att}=" do |value| 
        assoc = send("#{association_id.to_s}")
        unless assoc
          assoc = klass.new
          send("#{association_id.to_s}=",assoc)
        end
        
        assoc.send "#{att}=", value
      end
      send :define_method, "#{att}" do
        assoc = send("#{association_id.to_s}")
        
        unless assoc
          assoc = klass.new
          send("#{association_id.to_s}=",assoc)
        end
        return assoc.send "#{att}"
      end
    end
  end
end