to_xml

# File activesupport/lib/active_support/core_ext/hash/conversions.rb, line 18
        def to_xml(options = {})
          options[:indent] ||= 2
          options.reverse_merge!({ :builder => Builder::XmlMarkup.new(:indent => options[:indent]), :root => "hash" })
          options[:builder].instruct! unless options.delete(:skip_instruct)

          options[:builder].__send__(options[:root].to_s.dasherize) do
            each do |key, value|
              case value
                when ::Hash
                  value.to_xml(options.merge({ :root => key, :skip_instruct => true }))
                when ::Array
                  value.to_xml(options.merge({ :root => key, :children => key.to_s.singularize, :skip_instruct => true}))
                else
                  type_name = XML_TYPE_NAMES[value.class.to_s]

                  options[:builder].tag!(key.to_s.dasherize, 
                    XML_FORMATTING[type_name] ? XML_FORMATTING[type_name].call(value) : value,
                    options[:skip_types] || value.nil? || type_name.nil? ? { } : { :type => type_name }
                  )
              end
            end
          end
        end