javascript: serialize xml cross browser

gistfile1.js

/**
 * serialize xml to a string cross browser
 */

function xmlStringify(xmlNode) {
  // https://developer.mozilla.org/en-US/docs/XMLSerializer
  if (typeof XMLSerializer !== 'undefined') {
    return (new XMLSerializer()).serializeToString(xmlNode);
  }

  // IE
  if (xmlNode.xml) {
    return xmlNode.xml;
  }
  
  throw 'no method available to stringify xml';
}