import { Observable } from '../Observable'; import { OperatorFunction, ObservedValueOf } from '../../internal/types'; import { mergeMap } from './mergeMap'; import { ObservableInput } from '../types'; /* tslint:disable:max-line-length */ export function mergeMapTo<T, O extends ObservableInput<any>>(innerObservable: O, concurrent?: number): OperatorFunction<any, ObservedValueOf<O>>; /** @deprecated */ export function mergeMapTo<T, R, O extends ObservableInput<any>>(innerObservable: O, resultSelector: (outerValue: T, innerValue: ObservedValueOf<O>, outerIndex: number, innerIndex: number) => R, concurrent?: number): OperatorFunction<T, R>; /* tslint:enable:max-line-length */ /** * Projects each source value to the same Observable which is merged multiple * times in the output Observable. * * <span class="informal">It's like {@link mergeMap}, but maps each value always * to the same inner Observable.</span> * *  * * Maps each source value to the given Observable `innerObservable` regardless * of the source value, and then merges those resulting Observables into one * single Observable, which is the output Observable. * * ## Example * For each click event, start an interval Observable ticking every 1 second * ```ts * import { fromEvent, interval } from 'rxjs'; * import { mergeMapTo } from 'rxjs/operators'; * * const clicks = fromEvent(document, 'click'); * const result = clicks.pipe(mergeMapTo(interval(1000))); * result.subscribe(x => console.log(x)); * ``` * * @see {@link concatMapTo} * @see {@link merge} * @see {@link mergeAll} * @see {@link mergeMap} * @see {@link mergeScan} * @see {@link switchMapTo} * * @param {ObservableInput} innerObservable An Observable to replace each value from * the source Observable. * @param {number} [concurrent=Number.POSITIVE_INFINITY] Maximum number of input * Observables being subscribed to concurrently. * @return {Observable} An Observable that emits items from the given * `innerObservable` * @method mergeMapTo * @owner Observable */ export function mergeMapTo<T, R, O extends ObservableInput<any>>( innerObservable: O, resultSelector?: ((outerValue: T, innerValue: ObservedValueOf<O>, outerIndex: number, innerIndex: number) => R) | number, concurrent: number = Number.POSITIVE_INFINITY ): OperatorFunction<T, ObservedValueOf<O>|R> { if (typeof resultSelector === 'function') { return mergeMap(() => innerObservable, resultSelector, concurrent); } if (typeof resultSelector === 'number') { concurrent = resultSelector; } return mergeMap(() => innerObservable, concurrent); }