text: import { connectableObservableDescriptor } from '../observable/ConnectableObservable';
  /* tslint:enable:max-line-length */
  /**
   * 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.
   *
   * ![](multicast.png)
   *
   * @param {Function|Subject} subjectOrSubjectFactory - Factory function to create an intermediate subject through
   * which the source sequence's elements will be multicast to the selector function
   * or Subject to push source elements into.
   * @param {Function} [selector] - Optional selector 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.
   * @return {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.
   * @method multicast
   * @owner Observable
   */
  export function multicast(subjectOrSubjectFactory, selector) {
      return function multicastOperatorFunction(source) {
          let subjectFactory;
          if (typeof subjectOrSubjectFactory === 'function') {
              subjectFactory = subjectOrSubjectFactory;
          }
          else {
              subjectFactory = function subjectFactory() {
                  return subjectOrSubjectFactory;
              };
          }
          if (typeof selector === 'function') {
              return source.lift(new MulticastOperator(subjectFactory, selector));
          }
          const connectable = Object.create(source, connectableObservableDescriptor);
          connectable.source = source;
          connectable.subjectFactory = subjectFactory;
          return connectable;
      };
  }
  export class MulticastOperator {
      constructor(subjectFactory, selector) {
          this.subjectFactory = subjectFactory;
          this.selector = selector;
      }
      call(subscriber, source) {
          const { selector } = this;
          const subject = this.subjectFactory();
          const subscription = selector(subject).subscribe(subscriber);
          subscription.add(source.subscribe(subject));
          return subscription;
      }
  }
  