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- import { Subscriber } from '../Subscriber';
- export function refCount() {
- return function refCountOperatorFunction(source) {
- return source.lift(new RefCountOperator(source));
- };
- }
- class RefCountOperator {
- constructor(connectable) {
- this.connectable = connectable;
- }
- call(subscriber, source) {
- const { connectable } = this;
- connectable._refCount++;
- const refCounter = new RefCountSubscriber(subscriber, connectable);
- const subscription = source.subscribe(refCounter);
- if (!refCounter.closed) {
- refCounter.connection = connectable.connect();
- }
- return subscription;
- }
- }
- class RefCountSubscriber extends Subscriber {
- constructor(destination, connectable) {
- super(destination);
- this.connectable = connectable;
- }
- /** @deprecated internal use only */ _unsubscribe() {
- const { connectable } = this;
- if (!connectable) {
- this.connection = null;
- return;
- }
- this.connectable = null;
- const refCount = connectable._refCount;
- if (refCount <= 0) {
- this.connection = null;
- return;
- }
- connectable._refCount = refCount - 1;
- if (refCount > 1) {
- this.connection = null;
- return;
- }
- ///
- // Compare the local RefCountSubscriber's connection Subscription to the
- // connection Subscription on the shared ConnectableObservable. In cases
- // where the ConnectableObservable source synchronously emits values, and
- // the RefCountSubscriber's downstream Observers synchronously unsubscribe,
- // execution continues to here before the RefCountOperator has a chance to
- // supply the RefCountSubscriber with the shared connection Subscription.
- // For example:
- // ```
- // Observable.range(0, 10)
- // .publish()
- // .refCount()
- // .take(5)
- // .subscribe();
- // ```
- // In order to account for this case, RefCountSubscriber should only dispose
- // the ConnectableObservable's shared connection Subscription if the
- // connection Subscription exists, *and* either:
- // a. RefCountSubscriber doesn't have a reference to the shared connection
- // Subscription yet, or,
- // b. RefCountSubscriber's connection Subscription reference is identical
- // to the shared connection Subscription
- ///
- const { connection } = this;
- const sharedConnection = connectable._connection;
- this.connection = null;
- if (sharedConnection && (!connection || sharedConnection === connection)) {
- sharedConnection.unsubscribe();
- }
- }
- }
- //# sourceMappingURL=refCount.js.map
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