export default class Stateful{#e;#t=[];constructor(e){this.#e=e}get(){return this.#e}set(e){let t=this.#e;this.#e=e;for(let s in this.#t)this.#t[s](e,t)}update(e){this.set(e(this.#e))}onUpdate(e){return this.#t.push(e),e}removeListener(e){this.#t=this.#t.filter((t=>t!==e))}}