import { makeObservable, observable, action } from 'mobx'; export class Message { static _nextId = 0; id; text; author; // Person timestamp; static nextId() { return Message._nextId++; } constructor(text, author) { makeObservable(this, { text: observable, updateText: action, }); this.id = Message.nextId(); this.text = text; this.author = author; this.timestamp = new Date(); } updateText(text) { this.text = text; } }