method toDOM() for XML and XMLList object

toDOM.js

default xml namespace = "http://www.w3.org/1999/xhtml";
(function() {
   var parser = new DOMParser(),
       range = document.createRange();

   function toDOM(xmlns) {
     var pretty = XML.prettyPrinting;

     // disable prettyPringing temporary to avoid extra space inclusion
     XML.prettyPrinting = false;
     var doc = parser.parseFromString(
       '<root xmlns="' + xmlns + '">' + this.toXMLString() + "</root>",
       "application/xml");
     XML.prettyPrinting = pretty;

     range.selectNodeContents(
       document.importNode(doc.documentElement, true));
     var fragment = range.extractContents();
     return fragment.childNodes.length > 1 ? fragment : fragment.firstChild;
   };

   XML.prototype.function::toDOM = toDOM;
   XMLList.prototype.function::toDOM = toDOM;
 })();