请教这个JS代码运行后出现异常，缺少什么元素

请问这个JS代码运行后出现错误，缺少什么元素？

JScript code

(function(){    var _init = function() {        var debug = (location.hostname.indexOf('.taobao.com') == -1);        if (TB.bom.getCookie('_tb_defaultbackpop_') == 1 && !debug)            return;            var nowDate = new Date();        var nowTime =nowDate.getHours()*3600 + nowDate.getMinutes()*60 + nowDate.getSeconds();        var DAY = 24*3600;        var leaveTime = DAY - nowTime;        TB.bom.setCookie('_tb_defaultbackpop_', 1, leaveTime/DAY, document.domain, '/');            var popuped = false;        var popAd = function() {            if (popuped) return;            popuped = true;            var purl='http://www.taobao.com/promotion/defaultbackpop.html';            var w=760;            var h=480;            var adPopup = window.open('about:blank', '_blank','width='+w+',height='+h+', ...');            adPopup.blur();            adPopup.opener.focus();            adPopup.location = purl;            $E.removeListener(document.body, 'click', arguments.callee);            return adPopup;        }        try {            popAd();        } catch (e) {            popuped = false;            $E.on(document.body, 'click', popAd);        }    }    $E.on(window, 'load', _init);})();