class method self.method_missing

# File activerecord/lib/active_record/base.rb, line 1058
        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(<<-eowarn)
Calling dynamic finder with less number of arguments than the number of attributes in the method name is deprecated and will raise an ArgumentError in the next version of Rails. Please pass `nil' explicitly to the arguments that are left out.
                eowarn
            end
            if match.finder?
              options = if arguments.length > attribute_names.size
                          arguments.extract_options!
                        else
                          {}
                        end
              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 " \
                "the method name is deprecated and will raise an ArgumentError in the next version of Rails. " \
                "Please pass `nil' explicitly to the arguments that are left out."
              )
            end
            if match.scope?
              self.class_eval <<-METHOD, __FILE__, __LINE__ + 1
                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
              METHOD
              send(method_id, *arguments)
            end
          else
            super
          end
        end