import { InjectionToken } from '@angular/core';
import { Queue } from './queue/queue';
import { DeferQueueItem } from './service';
import { Observable } from "rxjs";
export declare const DEFER_QUEUE_FEATURE_BAILOUT: InjectionToken<boolean>;
export declare const DEFER_QUEUE_FEATURE_CONCURRENCY: InjectionToken<number | (() => number)>;
export declare const DEFER_QUEUE_FEATURE_QUEUE: InjectionToken<Queue<DeferQueueItem>>;
export declare const DEFER_QUEUE_FEATURE_ROUTING: InjectionToken<Observable<boolean>>;
export declare const DEFER_QUEUE_FEATURE_TIMEOUT: InjectionToken<number>;
export declare const DEFER_QUEUE_FEATURE_LOGGER: InjectionToken<Pick<Console, "info" | "warn" | "error" | "debug">>;