or();
            var parser = new DOMParser();
            var xsltDom = parser.parseFromString(xslt, "application/xml");
            // TODO: check errors .documentElement.nodeName == "parsererror"
            var xmlDom = parser.parseFromString(xml, "application/xml");
            processor.importStylesheet(xsltDom);
            if (typeof params !== 'undefined') {
                params.forEach(function(value, key) {
                    processor.setParameter("", key, value);
                });
       