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@reactivex/rxjs

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Reactive Extensions for modern JavaScript

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import { Subject } from './Subject'; import { queue } from './scheduler/queue'; import { ObserveOnSubscriber } from './operator/observeOn'; /** * @class ReplaySubject<T> */ export class ReplaySubject extends Subject { constructor(bufferSize = Number.POSITIVE_INFINITY, windowTime = Number.POSITIVE_INFINITY, scheduler) { super(); this.scheduler = scheduler; this._events = []; this._bufferSize = bufferSize < 1 ? 1 : bufferSize; this._windowTime = windowTime < 1 ? 1 : windowTime; } next(value) { const now = this._getNow(); this._events.push(new ReplayEvent(now, value)); this._trimBufferThenGetEvents(); super.next(value); } _subscribe(subscriber) { const _events = this._trimBufferThenGetEvents(); const scheduler = this.scheduler; if (scheduler) { subscriber.add(subscriber = new ObserveOnSubscriber(subscriber, scheduler)); } const len = _events.length; for (let i = 0; i < len && !subscriber.isUnsubscribed; i++) { subscriber.next(_events[i].value); } return super._subscribe(subscriber); } _getNow() { return (this.scheduler || queue).now(); } _trimBufferThenGetEvents() { const now = this._getNow(); const _bufferSize = this._bufferSize; const _windowTime = this._windowTime; const _events = this._events; let eventsCount = _events.length; let spliceCount = 0; // Trim events that fall out of the time window. // Start at the front of the list. Break early once // we encounter an event that falls within the window. while (spliceCount < eventsCount) { if ((now - _events[spliceCount].time) < _windowTime) { break; } spliceCount++; } if (eventsCount > _bufferSize) { spliceCount = Math.max(spliceCount, eventsCount - _bufferSize); } if (spliceCount > 0) { _events.splice(0, spliceCount); } return _events; } } class ReplayEvent { constructor(time, value) { this.time = time; this.value = value; } } //# sourceMappingURL=ReplaySubject.js.map