Method unsubscribe

src/state/Property.js:56–58

* Unsubscribes a listener from this property. * @param {function} callback The callback to unsubscribe.

(callback)

   * @param {function} callback The callback to unsubscribe.
   */
  unsubscribe(callback) {
    this.listeners = this.listeners.filter(listener => listener !== callback);
  }

  /**
   * Whether or not this property has any subscribed listeners