Shim .forEach => ECMAScript before v5

js: foreEach shim MDN

// Shim .forEach()
if ( !Array.prototype.forEach ) {
  Array.prototype.forEach = function(fn, scope) {
    for (var i = 0, len = this.length; i < len; ++i) {
      fn.call(scope || this, this[i], i, this);
    }
  }
}