@reactivex/rxjs
Version:
Reactive Extensions for modern JavaScript
223 lines • 9.02 kB
JavaScript
"use strict";
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 Subscriber_1 = require("../Subscriber");
var Observable_1 = require("../Observable");
var OuterSubscriber_1 = require("../OuterSubscriber");
var subscribeToResult_1 = require("../util/subscribeToResult");
/* tslint:disable:max-line-length */
/**
* Delays the emission of items from the source Observable by a given time span
* determined by the emissions of another Observable.
*
* <span class="informal">It's like {@link delay}, but the time span of the
* delay duration is determined by a second Observable.</span>
*
* 
*
* `delayWhen` time shifts each emitted value from the source Observable by a
* time span determined by another Observable. When the source emits a value,
* the `delayDurationSelector` function is called with the source value as
* argument, and should return an Observable, called the "duration" Observable.
* The source value is emitted on the output Observable only when the duration
* Observable emits a value or completes.
* The completion of the notifier triggering the emission of the source value
* is deprecated behavior and will be removed in future versions.
*
* Optionally, `delayWhen` takes a second argument, `subscriptionDelay`, which
* is an Observable. When `subscriptionDelay` emits its first value or
* completes, the source Observable is subscribed to and starts behaving like
* described in the previous paragraph. If `subscriptionDelay` is not provided,
* `delayWhen` will subscribe to the source Observable as soon as the output
* Observable is subscribed.
*
* ## Example
* Delay each click by a random amount of time, between 0 and 5 seconds
* ```ts
* import { fromEvent, interval } from 'rxjs';
* import { delayWhen } from 'rxjs/operators';
*
* const clicks = fromEvent(document, 'click');
* const delayedClicks = clicks.pipe(
* delayWhen(event => interval(Math.random() * 5000)),
* );
* delayedClicks.subscribe(x => console.log(x));
* ```
*
* @see {@link delay}
* @see {@link throttle}
* @see {@link throttleTime}
* @see {@link debounce}
* @see {@link debounceTime}
* @see {@link sample}
* @see {@link sampleTime}
* @see {@link audit}
* @see {@link auditTime}
*
* @param {function(value: T, index: number): Observable} delayDurationSelector A function that
* returns an Observable for each value emitted by the source Observable, which
* is then used to delay the emission of that item on the output Observable
* until the Observable returned from this function emits a value.
* @param {Observable} subscriptionDelay An Observable that triggers the
* subscription to the source Observable once it emits any value.
* @return {Observable} An Observable that delays the emissions of the source
* Observable by an amount of time specified by the Observable returned by
* `delayDurationSelector`.
* @method delayWhen
* @owner Observable
*/
function delayWhen(delayDurationSelector, subscriptionDelay) {
if (subscriptionDelay) {
return function (source) {
return new SubscriptionDelayObservable(source, subscriptionDelay)
.lift(new DelayWhenOperator(delayDurationSelector));
};
}
return function (source) { return source.lift(new DelayWhenOperator(delayDurationSelector)); };
}
exports.delayWhen = delayWhen;
var DelayWhenOperator = /** @class */ (function () {
function DelayWhenOperator(delayDurationSelector) {
this.delayDurationSelector = delayDurationSelector;
}
DelayWhenOperator.prototype.call = function (subscriber, source) {
return source.subscribe(new DelayWhenSubscriber(subscriber, this.delayDurationSelector));
};
return DelayWhenOperator;
}());
/**
* We need this JSDoc comment for affecting ESDoc.
* @ignore
* @extends {Ignored}
*/
var DelayWhenSubscriber = /** @class */ (function (_super) {
__extends(DelayWhenSubscriber, _super);
function DelayWhenSubscriber(destination, delayDurationSelector) {
var _this = _super.call(this, destination) || this;
_this.delayDurationSelector = delayDurationSelector;
_this.completed = false;
_this.delayNotifierSubscriptions = [];
_this.index = 0;
return _this;
}
DelayWhenSubscriber.prototype.notifyNext = function (outerValue, _innerValue, _outerIndex, _innerIndex, innerSub) {
this.destination.next(outerValue);
this.removeSubscription(innerSub);
this.tryComplete();
};
DelayWhenSubscriber.prototype.notifyError = function (error, innerSub) {
this._error(error);
};
DelayWhenSubscriber.prototype.notifyComplete = function (innerSub) {
var value = this.removeSubscription(innerSub);
if (value) {
this.destination.next(value);
}
this.tryComplete();
};
DelayWhenSubscriber.prototype._next = function (value) {
var index = this.index++;
try {
var delayNotifier = this.delayDurationSelector(value, index);
if (delayNotifier) {
this.tryDelay(delayNotifier, value);
}
}
catch (err) {
this.destination.error(err);
}
};
DelayWhenSubscriber.prototype._complete = function () {
this.completed = true;
this.tryComplete();
this.unsubscribe();
};
DelayWhenSubscriber.prototype.removeSubscription = function (subscription) {
subscription.unsubscribe();
var subscriptionIdx = this.delayNotifierSubscriptions.indexOf(subscription);
if (subscriptionIdx !== -1) {
this.delayNotifierSubscriptions.splice(subscriptionIdx, 1);
}
return subscription.outerValue;
};
DelayWhenSubscriber.prototype.tryDelay = function (delayNotifier, value) {
var notifierSubscription = subscribeToResult_1.subscribeToResult(this, delayNotifier, value);
if (notifierSubscription && !notifierSubscription.closed) {
var destination = this.destination;
destination.add(notifierSubscription);
this.delayNotifierSubscriptions.push(notifierSubscription);
}
};
DelayWhenSubscriber.prototype.tryComplete = function () {
if (this.completed && this.delayNotifierSubscriptions.length === 0) {
this.destination.complete();
}
};
return DelayWhenSubscriber;
}(OuterSubscriber_1.OuterSubscriber));
/**
* We need this JSDoc comment for affecting ESDoc.
* @ignore
* @extends {Ignored}
*/
var SubscriptionDelayObservable = /** @class */ (function (_super) {
__extends(SubscriptionDelayObservable, _super);
function SubscriptionDelayObservable(source, subscriptionDelay) {
var _this = _super.call(this) || this;
_this.source = source;
_this.subscriptionDelay = subscriptionDelay;
return _this;
}
/** @deprecated This is an internal implementation detail, do not use. */
SubscriptionDelayObservable.prototype._subscribe = function (subscriber) {
this.subscriptionDelay.subscribe(new SubscriptionDelaySubscriber(subscriber, this.source));
};
return SubscriptionDelayObservable;
}(Observable_1.Observable));
/**
* We need this JSDoc comment for affecting ESDoc.
* @ignore
* @extends {Ignored}
*/
var SubscriptionDelaySubscriber = /** @class */ (function (_super) {
__extends(SubscriptionDelaySubscriber, _super);
function SubscriptionDelaySubscriber(parent, source) {
var _this = _super.call(this) || this;
_this.parent = parent;
_this.source = source;
_this.sourceSubscribed = false;
return _this;
}
SubscriptionDelaySubscriber.prototype._next = function (unused) {
this.subscribeToSource();
};
SubscriptionDelaySubscriber.prototype._error = function (err) {
this.unsubscribe();
this.parent.error(err);
};
SubscriptionDelaySubscriber.prototype._complete = function () {
this.unsubscribe();
this.subscribeToSource();
};
SubscriptionDelaySubscriber.prototype.subscribeToSource = function () {
if (!this.sourceSubscribed) {
this.sourceSubscribed = true;
this.unsubscribe();
this.source.subscribe(this.parent);
}
};
return SubscriptionDelaySubscriber;
}(Subscriber_1.Subscriber));
//# sourceMappingURL=delayWhen.js.map