Function DOMTokenList

js/classlist_polyfill.js:12–20

(el)

      join = prototype.join;

  function DOMTokenList(el) {
    this.el = el;
    // The className needs to be trimmed and split on whitespace
    // to retrieve a list of classes.
    var classes = el.className.replace(/^\s+|\s+$/g, '').split(/\s+/);
    for (var i = 0; i < classes.length; i++) {
      push.call(this, classes[i]);
    }
  }

  DOMTokenList.prototype = {
    add: function (token) {