/**
 * @author Jörn Heinemann <joernheinemann@gmx.de>
 * @since 2021/09/16
 */
/**
 * Mix of:
 * - https://stackoverflow.com/a/51086893/12177973
 * - https://github.com/mgtitimoli/await-mutex/blob/master/src/mutex.js
 */
export declare class Mutex {
    private current;
    constructor();
    lock(): Promise<() => void>;
}