+++ /dev/null
-import { async } from '../scheduler/async';
-import { isDate } from '../util/isDate';
-import { Operator } from '../Operator';
-import { Subscriber } from '../Subscriber';
-import { Subscription } from '../Subscription';
-import { Notification } from '../Notification';
-import { Observable } from '../Observable';
-import { MonoTypeOperatorFunction, PartialObserver, SchedulerAction, SchedulerLike, TeardownLogic } from '../types';
-
-/**
- * Delays the emission of items from the source Observable by a given timeout or
- * until a given Date.
- *
- * <span class="informal">Time shifts each item by some specified amount of
- * milliseconds.</span>
- *
- * ![](delay.png)
- *
- * If the delay argument is a Number, this operator time shifts the source
- * Observable by that amount of time expressed in milliseconds. The relative
- * time intervals between the values are preserved.
- *
- * If the delay argument is a Date, this operator time shifts the start of the
- * Observable execution until the given date occurs.
- *
- * ## Examples
- * Delay each click by one second
- * ```ts
- * import { fromEvent } from 'rxjs';
- * import { delay } from 'rxjs/operators';
- *
- * const clicks = fromEvent(document, 'click');
- * const delayedClicks = clicks.pipe(delay(1000)); // each click emitted after 1 second
- * delayedClicks.subscribe(x => console.log(x));
- * ```
- *
- * Delay all clicks until a future date happens
- * ```ts
- * import { fromEvent } from 'rxjs';
- * import { delay } from 'rxjs/operators';
- *
- * const clicks = fromEvent(document, 'click');
- * const date = new Date('March 15, 2050 12:00:00'); // in the future
- * const delayedClicks = clicks.pipe(delay(date)); // click emitted only after that date
- * delayedClicks.subscribe(x => console.log(x));
- * ```
- *
- * @see {@link debounceTime}
- * @see {@link delayWhen}
- *
- * @param {number|Date} delay The delay duration in milliseconds (a `number`) or
- * a `Date` until which the emission of the source items is delayed.
- * @param {SchedulerLike} [scheduler=async] The {@link SchedulerLike} to use for
- * managing the timers that handle the time-shift for each item.
- * @return {Observable} An Observable that delays the emissions of the source
- * Observable by the specified timeout or Date.
- * @method delay
- * @owner Observable
- */
-export function delay<T>(delay: number|Date,
- scheduler: SchedulerLike = async): MonoTypeOperatorFunction<T> {
- const absoluteDelay = isDate(delay);
- const delayFor = absoluteDelay ? (+delay - scheduler.now()) : Math.abs(<number>delay);
- return (source: Observable<T>) => source.lift(new DelayOperator(delayFor, scheduler));
-}
-
-class DelayOperator<T> implements Operator<T, T> {
- constructor(private delay: number,
- private scheduler: SchedulerLike) {
- }
-
- call(subscriber: Subscriber<T>, source: any): TeardownLogic {
- return source.subscribe(new DelaySubscriber(subscriber, this.delay, this.scheduler));
- }
-}
-
-interface DelayState<T> {
- source: DelaySubscriber<T>;
- destination: PartialObserver<T>;
- scheduler: SchedulerLike;
-}
-
-/**
- * We need this JSDoc comment for affecting ESDoc.
- * @ignore
- * @extends {Ignored}
- */
-class DelaySubscriber<T> extends Subscriber<T> {
- private queue: Array<DelayMessage<T>> = [];
- private active: boolean = false;
- private errored: boolean = false;
-
- private static dispatch<T>(this: SchedulerAction<DelayState<T>>, state: DelayState<T>): void {
- const source = state.source;
- const queue = source.queue;
- const scheduler = state.scheduler;
- const destination = state.destination;
-
- while (queue.length > 0 && (queue[0].time - scheduler.now()) <= 0) {
- queue.shift().notification.observe(destination);
- }
-
- if (queue.length > 0) {
- const delay = Math.max(0, queue[0].time - scheduler.now());
- this.schedule(state, delay);
- } else {
- this.unsubscribe();
- source.active = false;
- }
- }
-
- constructor(destination: Subscriber<T>,
- private delay: number,
- private scheduler: SchedulerLike) {
- super(destination);
- }
-
- private _schedule(scheduler: SchedulerLike): void {
- this.active = true;
- const destination = this.destination as Subscription;
- destination.add(scheduler.schedule<DelayState<T>>(DelaySubscriber.dispatch, this.delay, {
- source: this, destination: this.destination, scheduler: scheduler
- }));
- }
-
- private scheduleNotification(notification: Notification<T>): void {
- if (this.errored === true) {
- return;
- }
-
- const scheduler = this.scheduler;
- const message = new DelayMessage(scheduler.now() + this.delay, notification);
- this.queue.push(message);
-
- if (this.active === false) {
- this._schedule(scheduler);
- }
- }
-
- protected _next(value: T) {
- this.scheduleNotification(Notification.createNext(value));
- }
-
- protected _error(err: any) {
- this.errored = true;
- this.queue = [];
- this.destination.error(err);
- this.unsubscribe();
- }
-
- protected _complete() {
- this.scheduleNotification(Notification.createComplete());
- this.unsubscribe();
- }
-}
-
-class DelayMessage<T> {
- constructor(public readonly time: number,
- public readonly notification: Notification<T>) {
- }
-}