1function $(el) {
2  return document.getElementById(el);
3}
4
5function $F(el) {
6  return $(el).value;
7}
8
9function bind(obj, func) {
10  return function() {
11    return func.apply(obj, arguments);
12  };
13}
14
15function childNodeWithClass(node, className) {
16  var expression = ".//*[@class='" + className + "']";
17  return document.evaluate(expression, node,
18      null, XPathResult.ANY_TYPE, null).iterateNext();
19}