method_missing

# File activerecord/lib/active_record/base.rb, line 1045
        def method_missing(method_id, *arguments, &block)
          if match = DynamicFinderMatch.match(method_id)
            attribute_names = match.attribute_names
            super unless all_attributes_exists?(attribute_names)
            if !arguments.first.is_a?(Hash) && arguments.size < attribute_names.size
              ActiveSupport::Deprecation.warn(Calling dynamic finder with less number of arguments than the number of attributes in method name is deprecated and will raise an ArguementError in the next version of Rails. Please passing `nil' to the argument you want it to be nil.)
            end
            if match.finder?
              options = arguments.extract_options!
              relation = options.any? ? scoped(options) : scoped
              relation.send :find_by_attributes, match, attribute_names, *arguments
            elsif match.instantiator?
              scoped.send :find_or_instantiator_by_attributes, match, attribute_names, *arguments, &block
            end
          elsif match = DynamicScopeMatch.match(method_id)
            attribute_names = match.attribute_names
            super unless all_attributes_exists?(attribute_names)
            if arguments.size < attribute_names.size
              ActiveSupport::Deprecation.warn(
                "Calling dynamic scope with less number of arguments than the number of attributes in "                  "method name is deprecated and will raise an ArguementError in the next version of Rails. "                  "Please passing `nil' to the argument you want it to be nil."
              )
            end
            if match.scope?
              self.class_eval                 def self.#{method_id}(*args)                                    # def self.scoped_by_user_name_and_password(*args)                  attributes = Hash[[:#{attribute_names.join(',:')}].zip(args)] #   attributes = Hash[[:user_name, :password].zip(args)]                                                                                #                  scoped(:conditions => attributes)                             #   scoped(:conditions => attributes)                end                                                             # end, __FILE__, __LINE__ + 1
              send(method_id, *arguments)
            end
          else
            super
          end
        end