doc.createElem('meta'); Uncaught ReferenceError: doc is not defined
<script>
//手机淘宝显示
var metaEl = doc.createElem('meta');
var scale = isRetina ?0.5 :1;
metaEl.setAttribute('name','viewport');
metaEl.setAttribute('content','initial-scale='+scale+',maximum-scale='+scale+',minimum-scale='+scale+',user-scalable=no');
if(docEl.firstElementChild){
document.documentElement.firstElementChild.appendChild(metaEl);
}else{
var wrap = doc.createElem('div');
wrap.appendChild(metaEl);
document.write(wrap.innerHTML);
}
</script>
