import { Observable } from 'rxjs';
export declare const createPollObservable: <TResult>(fetch$: Observable<TResult>, pollIn: number | Observable<number>) => Observable<TResult>;
/**
 * Must be called from an injection context (a constructor, a factory function or a field initializer).
 * Find more at https://angular.io/errors/NG0203
 */
export declare function viewDestroyed(): Observable<void>;
