import { Subject } from '../Subject';
import { ConnectableObservable } from '../observable/ConnectableObservable';
/**
 * Returns an Observable that emits the results of invoking a specified selector on items
 * emitted by a ConnectableObservable that shares a single subscription to the underlying stream.
 *
 * <img src="./img/multicast.png" width="100%">
 *
 * @param {Function} selector - a function that can use the multicasted source stream
 * as many times as needed, without causing multiple subscriptions to the source stream.
 * Subscribers to the given source will receive all notifications of the source from the
 * time of the subscription forward.
 * @returns {Observable} an Observable that emits the results of invoking the selector
 * on the items emitted by a `ConnectableObservable` that shares a single subscription to
 * the underlying stream.
 */
export declare function multicast<T>(subjectOrSubjectFactory: Subject<T> | (() => Subject<T>)): ConnectableObservable<T>;