/** 小型 FIFO worker pool；每个 worker 同时只执行一个任务。 */
export declare class WorkerPool {
    readonly concurrency: number;
    private available;
    private waiters;
    private active;
    constructor(concurrency: number);
    run<T>(task: (workerIndex: number, queueWaitMs: number) => Promise<T>): Promise<T>;
    get activeCount(): number;
    private acquire;
    private release;
}
export declare function boundedWorkerConcurrency(value: unknown, fallback?: number, maximum?: number): number;