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- import { switchMap as higherOrderSwitchMap } from '../operators/switchMap';
- /* tslint:enable:max-line-length */
- /**
- * Projects each source value to an Observable which is merged in the output
- * Observable, emitting values only from the most recently projected Observable.
- *
- * <span class="informal">Maps each value to an Observable, then flattens all of
- * these inner Observables using {@link switch}.</span>
- *
- * <img src="./img/switchMap.png" width="100%">
- *
- * Returns an Observable that emits items based on applying a function that you
- * supply to each item emitted by the source Observable, where that function
- * returns an (so-called "inner") Observable. Each time it observes one of these
- * inner Observables, the output Observable begins emitting the items emitted by
- * that inner Observable. When a new inner Observable is emitted, `switchMap`
- * stops emitting items from the earlier-emitted inner Observable and begins
- * emitting items from the new one. It continues to behave like this for
- * subsequent inner Observables.
- *
- * @example <caption>Rerun an interval Observable on every click event</caption>
- * var clicks = Rx.Observable.fromEvent(document, 'click');
- * var result = clicks.switchMap((ev) => Rx.Observable.interval(1000));
- * result.subscribe(x => console.log(x));
- *
- * @see {@link concatMap}
- * @see {@link exhaustMap}
- * @see {@link mergeMap}
- * @see {@link switch}
- * @see {@link switchMapTo}
- *
- * @param {function(value: T, ?index: number): ObservableInput} project A function
- * that, when applied to an item emitted by the source Observable, returns an
- * Observable.
- * @param {function(outerValue: T, innerValue: I, outerIndex: number, innerIndex: number): any} [resultSelector]
- * A function to produce the value on the output Observable based on the values
- * and the indices of the source (outer) emission and the inner Observable
- * emission. The arguments passed to this function are:
- * - `outerValue`: the value that came from the source
- * - `innerValue`: the value that came from the projected Observable
- * - `outerIndex`: the "index" of the value that came from the source
- * - `innerIndex`: the "index" of the value from the projected Observable
- * @return {Observable} An Observable that emits the result of applying the
- * projection function (and the optional `resultSelector`) to each item emitted
- * by the source Observable and taking only the values from the most recently
- * projected inner Observable.
- * @method switchMap
- * @owner Observable
- */
- export function switchMap(project, resultSelector) {
- return higherOrderSwitchMap(project, resultSelector)(this);
- }
- //# sourceMappingURL=switchMap.js.map
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