gistfile1.rb

module ActsAsHistorical
  extend ActiveSupport::Concern
 
  included do
  end

  module ClassMethods
    def acts_as_historical(options = {})
      has_many :histories, :as => :historical, :dependent => :destroy
      include MyInstanceMethods
    end
  end

  module MyInstanceMethods

    module ArrayProxy
      def <<(entry)
        @__parent__.add_history(entry)
        super
      end
    end

    def add_history(text)
      histories.create(:entry => text)
    end

    def clear_history
      histories.destroy_all
    end

    def history
      histories.map(&:entry).tap { |h| h.extend(ArrayProxy).instance_variable_set(:@__parent__, self) }
    end

  end

end