| import { SimpleOuterSubscriber, SimpleInnerSubscriber, innerSubscribe } from '../innerSubscribe'; | 
| export function mergeScan(accumulator, seed, concurrent = Number.POSITIVE_INFINITY) { | 
|     return (source) => source.lift(new MergeScanOperator(accumulator, seed, concurrent)); | 
| } | 
| export class MergeScanOperator { | 
|     constructor(accumulator, seed, concurrent) { | 
|         this.accumulator = accumulator; | 
|         this.seed = seed; | 
|         this.concurrent = concurrent; | 
|     } | 
|     call(subscriber, source) { | 
|         return source.subscribe(new MergeScanSubscriber(subscriber, this.accumulator, this.seed, this.concurrent)); | 
|     } | 
| } | 
| export class MergeScanSubscriber extends SimpleOuterSubscriber { | 
|     constructor(destination, accumulator, acc, concurrent) { | 
|         super(destination); | 
|         this.accumulator = accumulator; | 
|         this.acc = acc; | 
|         this.concurrent = concurrent; | 
|         this.hasValue = false; | 
|         this.hasCompleted = false; | 
|         this.buffer = []; | 
|         this.active = 0; | 
|         this.index = 0; | 
|     } | 
|     _next(value) { | 
|         if (this.active < this.concurrent) { | 
|             const index = this.index++; | 
|             const destination = this.destination; | 
|             let ish; | 
|             try { | 
|                 const { accumulator } = this; | 
|                 ish = accumulator(this.acc, value, index); | 
|             } | 
|             catch (e) { | 
|                 return destination.error(e); | 
|             } | 
|             this.active++; | 
|             this._innerSub(ish); | 
|         } | 
|         else { | 
|             this.buffer.push(value); | 
|         } | 
|     } | 
|     _innerSub(ish) { | 
|         const innerSubscriber = new SimpleInnerSubscriber(this); | 
|         const destination = this.destination; | 
|         destination.add(innerSubscriber); | 
|         const innerSubscription = innerSubscribe(ish, innerSubscriber); | 
|         if (innerSubscription !== innerSubscriber) { | 
|             destination.add(innerSubscription); | 
|         } | 
|     } | 
|     _complete() { | 
|         this.hasCompleted = true; | 
|         if (this.active === 0 && this.buffer.length === 0) { | 
|             if (this.hasValue === false) { | 
|                 this.destination.next(this.acc); | 
|             } | 
|             this.destination.complete(); | 
|         } | 
|         this.unsubscribe(); | 
|     } | 
|     notifyNext(innerValue) { | 
|         const { destination } = this; | 
|         this.acc = innerValue; | 
|         this.hasValue = true; | 
|         destination.next(innerValue); | 
|     } | 
|     notifyComplete() { | 
|         const buffer = this.buffer; | 
|         this.active--; | 
|         if (buffer.length > 0) { | 
|             this._next(buffer.shift()); | 
|         } | 
|         else if (this.active === 0 && this.hasCompleted) { | 
|             if (this.hasValue === false) { | 
|                 this.destination.next(this.acc); | 
|             } | 
|             this.destination.complete(); | 
|         } | 
|     } | 
| } | 
| //# sourceMappingURL=mergeScan.js.map |