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- import { concatMap as higherOrderConcatMap } from '../operators/concatMap';
- /* tslint:enable:max-line-length */
- /**
- * Projects each source value to an Observable which is merged in the output
- * Observable, in a serialized fashion waiting for each one to complete before
- * merging the next.
- *
- * <span class="informal">Maps each value to an Observable, then flattens all of
- * these inner Observables using {@link concatAll}.</span>
- *
- * <img src="./img/concatMap.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 new inner Observable is
- * concatenated with the previous inner Observable.
- *
- * __Warning:__ if source values arrive endlessly and faster than their
- * corresponding inner Observables can complete, it will result in memory issues
- * as inner Observables amass in an unbounded buffer waiting for their turn to
- * be subscribed to.
- *
- * Note: `concatMap` is equivalent to `mergeMap` with concurrency parameter set
- * to `1`.
- *
- * @example <caption>For each click event, tick every second from 0 to 3, with no concurrency</caption>
- * var clicks = Rx.Observable.fromEvent(document, 'click');
- * var result = clicks.concatMap(ev => Rx.Observable.interval(1000).take(4));
- * result.subscribe(x => console.log(x));
- *
- * // Results in the following:
- * // (results are not concurrent)
- * // For every click on the "document" it will emit values 0 to 3 spaced
- * // on a 1000ms interval
- * // one click = 1000ms-> 0 -1000ms-> 1 -1000ms-> 2 -1000ms-> 3
- *
- * @see {@link concat}
- * @see {@link concatAll}
- * @see {@link concatMapTo}
- * @see {@link exhaustMap}
- * @see {@link mergeMap}
- * @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
- * @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 values from each projected inner
- * Observable sequentially.
- * @method concatMap
- * @owner Observable
- */
- export function concatMap(project, resultSelector) {
- return higherOrderConcatMap(project, resultSelector)(this);
- }
- //# sourceMappingURL=concatMap.js.map
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