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173 lines
6.5 KiB
173 lines
6.5 KiB
"use strict"; |
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var __extends = (this && this.__extends) || function (d, b) { |
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for (var p in b) if (b.hasOwnProperty(p)) d[p] = b[p]; |
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function __() { this.constructor = d; } |
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d.prototype = b === null ? Object.create(b) : (__.prototype = b.prototype, new __()); |
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}; |
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var subscribeToResult_1 = require('../util/subscribeToResult'); |
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var OuterSubscriber_1 = require('../OuterSubscriber'); |
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/* tslint:enable:max-line-length */ |
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/** |
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* Projects each source value to an Observable which is merged in the output |
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* Observable. |
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* |
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* <span class="informal">Maps each value to an Observable, then flattens all of |
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* these inner Observables using {@link mergeAll}.</span> |
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* |
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* <img src="./img/mergeMap.png" width="100%"> |
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* |
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* Returns an Observable that emits items based on applying a function that you |
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* supply to each item emitted by the source Observable, where that function |
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* returns an Observable, and then merging those resulting Observables and |
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* emitting the results of this merger. |
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* |
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* @example <caption>Map and flatten each letter to an Observable ticking every 1 second</caption> |
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* var letters = Rx.Observable.of('a', 'b', 'c'); |
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* var result = letters.mergeMap(x => |
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* Rx.Observable.interval(1000).map(i => x+i) |
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* ); |
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* result.subscribe(x => console.log(x)); |
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* |
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* // Results in the following: |
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* // a0 |
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* // b0 |
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* // c0 |
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* // a1 |
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* // b1 |
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* // c1 |
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* // continues to list a,b,c with respective ascending integers |
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* |
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* @see {@link concatMap} |
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* @see {@link exhaustMap} |
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* @see {@link merge} |
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* @see {@link mergeAll} |
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* @see {@link mergeMapTo} |
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* @see {@link mergeScan} |
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* @see {@link switchMap} |
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* |
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* @param {function(value: T, ?index: number): ObservableInput} project A function |
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* that, when applied to an item emitted by the source Observable, returns an |
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* Observable. |
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* @param {function(outerValue: T, innerValue: I, outerIndex: number, innerIndex: number): any} [resultSelector] |
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* A function to produce the value on the output Observable based on the values |
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* and the indices of the source (outer) emission and the inner Observable |
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* emission. The arguments passed to this function are: |
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* - `outerValue`: the value that came from the source |
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* - `innerValue`: the value that came from the projected Observable |
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* - `outerIndex`: the "index" of the value that came from the source |
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* - `innerIndex`: the "index" of the value from the projected Observable |
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* @param {number} [concurrent=Number.POSITIVE_INFINITY] Maximum number of input |
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* Observables being subscribed to concurrently. |
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* @return {Observable} An Observable that emits the result of applying the |
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* projection function (and the optional `resultSelector`) to each item emitted |
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* by the source Observable and merging the results of the Observables obtained |
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* from this transformation. |
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* @method mergeMap |
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* @owner Observable |
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*/ |
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function mergeMap(project, resultSelector, concurrent) { |
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if (concurrent === void 0) { concurrent = Number.POSITIVE_INFINITY; } |
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return function mergeMapOperatorFunction(source) { |
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if (typeof resultSelector === 'number') { |
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concurrent = resultSelector; |
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resultSelector = null; |
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} |
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return source.lift(new MergeMapOperator(project, resultSelector, concurrent)); |
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}; |
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} |
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exports.mergeMap = mergeMap; |
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var MergeMapOperator = (function () { |
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function MergeMapOperator(project, resultSelector, concurrent) { |
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if (concurrent === void 0) { concurrent = Number.POSITIVE_INFINITY; } |
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this.project = project; |
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this.resultSelector = resultSelector; |
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this.concurrent = concurrent; |
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} |
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MergeMapOperator.prototype.call = function (observer, source) { |
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return source.subscribe(new MergeMapSubscriber(observer, this.project, this.resultSelector, this.concurrent)); |
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}; |
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return MergeMapOperator; |
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}()); |
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exports.MergeMapOperator = MergeMapOperator; |
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/** |
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* We need this JSDoc comment for affecting ESDoc. |
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* @ignore |
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* @extends {Ignored} |
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*/ |
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var MergeMapSubscriber = (function (_super) { |
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__extends(MergeMapSubscriber, _super); |
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function MergeMapSubscriber(destination, project, resultSelector, concurrent) { |
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if (concurrent === void 0) { concurrent = Number.POSITIVE_INFINITY; } |
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_super.call(this, destination); |
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this.project = project; |
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this.resultSelector = resultSelector; |
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this.concurrent = concurrent; |
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this.hasCompleted = false; |
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this.buffer = []; |
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this.active = 0; |
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this.index = 0; |
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} |
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MergeMapSubscriber.prototype._next = function (value) { |
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if (this.active < this.concurrent) { |
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this._tryNext(value); |
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} |
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else { |
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this.buffer.push(value); |
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} |
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}; |
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MergeMapSubscriber.prototype._tryNext = function (value) { |
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var result; |
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var index = this.index++; |
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try { |
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result = this.project(value, index); |
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} |
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catch (err) { |
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this.destination.error(err); |
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return; |
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} |
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this.active++; |
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this._innerSub(result, value, index); |
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}; |
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MergeMapSubscriber.prototype._innerSub = function (ish, value, index) { |
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this.add(subscribeToResult_1.subscribeToResult(this, ish, value, index)); |
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}; |
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MergeMapSubscriber.prototype._complete = function () { |
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this.hasCompleted = true; |
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if (this.active === 0 && this.buffer.length === 0) { |
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this.destination.complete(); |
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} |
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}; |
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MergeMapSubscriber.prototype.notifyNext = function (outerValue, innerValue, outerIndex, innerIndex, innerSub) { |
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if (this.resultSelector) { |
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this._notifyResultSelector(outerValue, innerValue, outerIndex, innerIndex); |
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} |
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else { |
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this.destination.next(innerValue); |
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} |
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}; |
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MergeMapSubscriber.prototype._notifyResultSelector = function (outerValue, innerValue, outerIndex, innerIndex) { |
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var result; |
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try { |
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result = this.resultSelector(outerValue, innerValue, outerIndex, innerIndex); |
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} |
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catch (err) { |
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this.destination.error(err); |
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return; |
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} |
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this.destination.next(result); |
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}; |
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MergeMapSubscriber.prototype.notifyComplete = function (innerSub) { |
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var buffer = this.buffer; |
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this.remove(innerSub); |
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this.active--; |
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if (buffer.length > 0) { |
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this._next(buffer.shift()); |
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} |
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else if (this.active === 0 && this.hasCompleted) { |
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this.destination.complete(); |
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} |
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}; |
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return MergeMapSubscriber; |
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}(OuterSubscriber_1.OuterSubscriber)); |
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exports.MergeMapSubscriber = MergeMapSubscriber; |
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//# sourceMappingURL=mergeMap.js.map
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