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- import { defaultIfEmpty as higherOrder } from '../operators/defaultIfEmpty';
- /* tslint:enable:max-line-length */
- /**
- * Emits a given value if the source Observable completes without emitting any
- * `next` value, otherwise mirrors the source Observable.
- *
- * <span class="informal">If the source Observable turns out to be empty, then
- * this operator will emit a default value.</span>
- *
- * <img src="./img/defaultIfEmpty.png" width="100%">
- *
- * `defaultIfEmpty` emits the values emitted by the source Observable or a
- * specified default value if the source Observable is empty (completes without
- * having emitted any `next` value).
- *
- * @example <caption>If no clicks happen in 5 seconds, then emit "no clicks"</caption>
- * var clicks = Rx.Observable.fromEvent(document, 'click');
- * var clicksBeforeFive = clicks.takeUntil(Rx.Observable.interval(5000));
- * var result = clicksBeforeFive.defaultIfEmpty('no clicks');
- * result.subscribe(x => console.log(x));
- *
- * @see {@link empty}
- * @see {@link last}
- *
- * @param {any} [defaultValue=null] The default value used if the source
- * Observable is empty.
- * @return {Observable} An Observable that emits either the specified
- * `defaultValue` if the source Observable emits no items, or the values emitted
- * by the source Observable.
- * @method defaultIfEmpty
- * @owner Observable
- */
- export function defaultIfEmpty(defaultValue = null) {
- return higherOrder(defaultValue)(this);
- }
- //# sourceMappingURL=defaultIfEmpty.js.map
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