import { Observable } from 'rxjs';
export declare class RequestPool {
    private readonly maxParallel;
    private readonly runnerQueue;
    private runningCount;
    constructor({ maxParallel }: {
        maxParallel: number;
    });
    queue<T>(request: Observable<T>): Observable<T>;
    private flushQueue;
}
export declare function maxParallelByHttpVersion(http_2?: number, http_1?: number): number;