/**
 * A mutex (mutual exclusion) is a lock which enforces limited access to a resource in asynchronous/multi-threaded environments.
 *
 * Acquiring this lock returns a release function function (via promise) which needs to be called to release the lock again.
 */
interface MutexInterface {
  /**
   * acquires the lock and returns a Promise with the release function to be called when the lock shall be released.
   * This release function needs to be called or the lock will never release and execution of subsequent consumers will not take place.
   * Always think about possible error states and release the lock accordingly.
   */
  acquire(): Promise<Mutex.ReleaseFunction>;

  /**
   * release the lock and execute the next consumer.
   */
  release(): void;

  /**
   * release the lock and do not allow any current consumers to execute.
   */
  reset(): void;

  isLocked(): boolean;
}

declare namespace Mutex {
  type ReleaseFunction = () => void;
}