forEach.js

if (!Array.prototype.forEach) {
  Array.prototype.forEach = function(callback, thisArg) {
    if (this === null) {
      throw new TypeError('Array.prototype.forEach called on null or undefined');
    }
    if (typeof callback !== "function") {
      throw new TypeError(callback + ' is not a function');
    }
    var O = Object(this), len = O.length >>> 0, k = 0, value;
    if (arguments.length > 1) {
      value = thisArg;
    }
    while (k < len) {
      if (k in O) {
        callback.call(value, O[k], k, O);
      }
      k++;
    }
  };
}