window.onload = function (){ 
document.body.clientWidth; 
var elems = document.querySelectorAll('[data-insert]'); 
Array.from(elems).forEach(function (e){ 
var parent, ref; 
switch (e.dataset.insert){ 
case 'start': parent = e; 
ref = e.firstChild; 
break ; 
case 'end': parent = e; 
ref = null ; 
break ; 
case 'before': parent = e.parentNode; 
ref = e; 
break ; 
case 'after': parent = e.parentNode; 
ref = e.nextSibling; 
break ; 
} 
var elem, textnode; 
if ('text' in e.dataset) { 
textnode = document.createTextNode(e.dataset.text); 
} 
if ('tag' in e.dataset) { 
elem = _AN_Call_createelement('createElement', document, e.dataset.tag); 
if (textnode) { 
_AN_Call_appendchild('appendChild', elem, textnode); 
} 
} 
parent.insertBefore(elem? elem: textnode, ref); 
} 
); 
} 
;