HarmonyOS语法错误有哪些？

type ObserverFactory<T> = () => T; 
class ObserverManager { 
  private observerMap: Map<string, MObserver[]> = new Map<string, MObserver[]>(); 
  constructor() { 
  } 
  public getObservers<T extends MObserver>(observerFactory: ObserverFactory<T>): T[] { 
    const observerList: T[] = []; 
    this.observerMap.forEach((observers) => { 
      observers.forEach((observer) => { 
        if (observer instanceof observerFactory) { 
          observerList.push(observer as T); 
        } 
      }); 
    }); 
    return observerList; 
  } 
} 
// 假设 MObserver 是所有观察者的基类 
class MObserver { 
  // 基本的观察者类可以包含一些通用的方法或属性 
}