# File lib/active_record/validations.rb, line 79
    def add_on_blank(attributes, msg = @@default_error_messages[:blank])
      for attr in [attributes].flatten
        value = @base.respond_to?(attr.to_s) ? @base.send(attr.to_s) : @base[attr.to_s]
        add(attr, msg) if value.blank?
      end
    end