69 lines
2.8 KiB
JavaScript
69 lines
2.8 KiB
JavaScript
|
/** PURE_IMPORTS_START .._operators_mergeMap PURE_IMPORTS_END */
|
||
|
|
import { mergeMap as higherOrderMergeMap } from '../operators/mergeMap';
|
||
|
|
/* tslint:enable:max-line-length */
|
||
|
|
/**
|
||
|
|
* Projects each source value to an Observable which is merged in the output
|
||
|
|
* Observable.
|
||
|
|
*
|
||
|
|
* <span class="informal">Maps each value to an Observable, then flattens all of
|
||
|
|
* these inner Observables using {@link mergeAll}.</span>
|
||
|
|
*
|
||
|
|
* <img src="./img/mergeMap.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 Observable, and then merging those resulting Observables and
|
||
|
|
* emitting the results of this merger.
|
||
|
|
*
|
||
|
|
* @example <caption>Map and flatten each letter to an Observable ticking every 1 second</caption>
|
||
|
|
* var letters = Rx.Observable.of('a', 'b', 'c');
|
||
|
|
* var result = letters.mergeMap(x =>
|
||
|
|
* Rx.Observable.interval(1000).map(i => x+i)
|
||
|
|
* );
|
||
|
|
* result.subscribe(x => console.log(x));
|
||
|
|
*
|
||
|
|
* // Results in the following:
|
||
|
|
* // a0
|
||
|
|
* // b0
|
||
|
|
* // c0
|
||
|
|
* // a1
|
||
|
|
* // b1
|
||
|
|
* // c1
|
||
|
|
* // continues to list a,b,c with respective ascending integers
|
||
|
|
*
|
||
|
|
* @see {@link concatMap}
|
||
|
|
* @see {@link exhaustMap}
|
||
|
|
* @see {@link merge}
|
||
|
|
* @see {@link mergeAll}
|
||
|
|
* @see {@link mergeMapTo}
|
||
|
|
* @see {@link mergeScan}
|
||
|
|
* @see {@link switchMap}
|
||
|
|
*
|
||
|
|
* @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
|
||
|
|
* @param {number} [concurrent=Number.POSITIVE_INFINITY] Maximum number of input
|
||
|
|
* Observables being subscribed to concurrently.
|
||
|
|
* @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 merging the results of the Observables obtained
|
||
|
|
* from this transformation.
|
||
|
|
* @method mergeMap
|
||
|
|
* @owner Observable
|
||
|
|
*/
|
||
|
|
export function mergeMap(project, resultSelector, concurrent) {
|
||
|
|
if (concurrent === void 0) {
|
||
|
|
concurrent = Number.POSITIVE_INFINITY;
|
||
|
|
}
|
||
|
|
return higherOrderMergeMap(project, resultSelector, concurrent)(this);
|
||
|
|
}
|
||
|
|
//# sourceMappingURL=mergeMap.js.map
|