我有一个由myFirstAction触发的Angular 效果，它应该进行轮询，直到在后端创建了一个文件，然后调度另一个操作：

myEffect = createEffect(() =>
    this.actions$.pipe(
      ofType(Actions.myFirstAction),
      withLatestFrom(
        this.store.select(Selectors.fileName)
      ),
      switchMap(([payload, fileName]) =>
          this.pollTillFileCreated(fileName)),
        map(() => Actions.mySecondAction()),
        catchError((error) => {
           return of(Actions.errorAction(error));
        })
      )
    );

我的投票方式是

private pollTillFileCreated(fileName: string): Observable<boolean> {
    return timer(0, 1000).pipe(
      concatMap(() => this.service.fileExist(fileName)),
      takeWhile((doesExist: boolean) => !doesExist),
      takeLast(1)
    );
  }

虽然我可以看到HTTP调用返回doesExist: true，但mySecondAction没有被调度。