Method for

src/array-observation.js:135–143

* Searches for observer or creates a new one associated with given array instance * @param taskQueue * @param array instance for which observer is searched * @returns ModifyArrayObserver always the same instance for any given array instance

(taskQueue, array)

   * @returns ModifyArrayObserver always the same instance for any given array instance
   */
  static for(taskQueue, array) {
    if (!('__array_observer__' in array)) {
      Reflect.defineProperty(array, '__array_observer__', {
        value: ModifyArrayObserver.create(taskQueue, array),
        enumerable: false, configurable: false
      });
    }
    return array.__array_observer__;
  }

  static create(taskQueue, array) {
    return new ModifyArrayObserver(taskQueue, array);