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@reactivex/rxjs

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Reactive Extensions for modern JavaScript

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import { Subscriber } from '../Subscriber'; /** * If the source Observable is empty it returns an Observable that emits true, otherwise it emits false. * * <img src="./img/isEmpty.png" width="100%"> * * @return {Observable} an Observable that emits a Boolean. * @method isEmpty * @owner Observable */ export function isEmpty() { return this.lift(new IsEmptyOperator()); } var IsEmptyOperator = (function () { function IsEmptyOperator() { } IsEmptyOperator.prototype.call = function (observer, source) { return source._subscribe(new IsEmptySubscriber(observer)); }; return IsEmptyOperator; }()); /** * We need this JSDoc comment for affecting ESDoc. * @ignore * @extends {Ignored} */ var IsEmptySubscriber = (function (_super) { __extends(IsEmptySubscriber, _super); function IsEmptySubscriber(destination) { _super.call(this, destination); } IsEmptySubscriber.prototype.notifyComplete = function (isEmpty) { var destination = this.destination; destination.next(isEmpty); destination.complete(); }; IsEmptySubscriber.prototype._next = function (value) { this.notifyComplete(false); }; IsEmptySubscriber.prototype._complete = function () { this.notifyComplete(true); }; return IsEmptySubscriber; }(Subscriber)); //# sourceMappingURL=isEmpty.js.map