import type { ObservableInput } from 'rxjs';
import { ObservableState } from './observableState';
/**
 * Make this stream a ObservableState stream of its source.
 *
 * @param name The unique name of this stream
 * @param source$ The source of this stream
 */
export declare const persistentDerivedStream: <State>(name: string, source$: ObservableInput<State>, initialState: State) => ObservableState<State>;