<!DOCTYPE html>
<html>
<head>
<script>

function boom()
{
  var a = document.createElementNS("http://www.w3.org/1999/xhtml", "datalist");
  var b = document.createElementNS("http://www.w3.org/1999/xhtml", "option");

  a.appendChild(b);
  b.expando = a.options;
}

</script>
</head>
<body onload="boom();"></body>
</html>