@reactivex/rxjs
Version:
Reactive Extensions for modern JavaScript
128 lines • 4.45 kB
JavaScript
;
var __extends = (this && this.__extends) || (function () {
var extendStatics = function (d, b) {
extendStatics = Object.setPrototypeOf ||
({ __proto__: [] } instanceof Array && function (d, b) { d.__proto__ = b; }) ||
function (d, b) { for (var p in b) if (b.hasOwnProperty(p)) d[p] = b[p]; };
return extendStatics(d, b);
}
return function (d, b) {
extendStatics(d, b);
function __() { this.constructor = d; }
d.prototype = b === null ? Object.create(b) : (__.prototype = b.prototype, new __());
};
})();
Object.defineProperty(exports, "__esModule", { value: true });
var isArray_1 = require("../util/isArray");
var fromArray_1 = require("./fromArray");
var OuterSubscriber_1 = require("../OuterSubscriber");
var subscribeToResult_1 = require("../util/subscribeToResult");
/**
* Returns an Observable that mirrors the first source Observable to emit an item.
*
* ## Example
* ### Subscribes to the observable that was the first to start emitting.
*
* ```ts
* import { race, interval } from 'rxjs';
* import { mapTo } from 'rxjs/operators';
*
* const obs1 = interval(1000).pipe(mapTo('fast one'));
* const obs2 = interval(3000).pipe(mapTo('medium one'));
* const obs3 = interval(5000).pipe(mapTo('slow one'));
*
* race(obs3, obs1, obs2)
* .subscribe(
* winner => console.log(winner)
* );
*
* // result:
* // a series of 'fast one'
* ```
*
* @param {...Observables} ...observables sources used to race for which Observable emits first.
* @return {Observable} an Observable that mirrors the output of the first Observable to emit an item.
* @static true
* @name race
* @owner Observable
*/
function race() {
var observables = [];
for (var _i = 0; _i < arguments.length; _i++) {
observables[_i] = arguments[_i];
}
// if the only argument is an array, it was most likely called with
// `race([obs1, obs2, ...])`
if (observables.length === 1) {
if (isArray_1.isArray(observables[0])) {
observables = observables[0];
}
else {
return observables[0];
}
}
return fromArray_1.fromArray(observables, undefined).lift(new RaceOperator());
}
exports.race = race;
var RaceOperator = /** @class */ (function () {
function RaceOperator() {
}
RaceOperator.prototype.call = function (subscriber, source) {
return source.subscribe(new RaceSubscriber(subscriber));
};
return RaceOperator;
}());
exports.RaceOperator = RaceOperator;
/**
* We need this JSDoc comment for affecting ESDoc.
* @ignore
* @extends {Ignored}
*/
var RaceSubscriber = /** @class */ (function (_super) {
__extends(RaceSubscriber, _super);
function RaceSubscriber(destination) {
var _this = _super.call(this, destination) || this;
_this.hasFirst = false;
_this.observables = [];
_this.subscriptions = [];
return _this;
}
RaceSubscriber.prototype._next = function (observable) {
this.observables.push(observable);
};
RaceSubscriber.prototype._complete = function () {
var observables = this.observables;
var len = observables.length;
if (len === 0) {
this.destination.complete();
}
else {
for (var i = 0; i < len && !this.hasFirst; i++) {
var observable = observables[i];
var subscription = subscribeToResult_1.subscribeToResult(this, observable, undefined, i);
if (this.subscriptions) {
this.subscriptions.push(subscription);
}
this.add(subscription);
}
this.observables = null;
}
};
RaceSubscriber.prototype.notifyNext = function (_outerValue, innerValue, outerIndex) {
if (!this.hasFirst) {
this.hasFirst = true;
for (var i = 0; i < this.subscriptions.length; i++) {
if (i !== outerIndex) {
var subscription = this.subscriptions[i];
subscription.unsubscribe();
this.remove(subscription);
}
}
this.subscriptions = null;
}
this.destination.next(innerValue);
};
return RaceSubscriber;
}(OuterSubscriber_1.OuterSubscriber));
exports.RaceSubscriber = RaceSubscriber;
//# sourceMappingURL=race.js.map