export declare class Lock {
	protected _callbacks: Function[];
	protected _counter: number;
	protected _parent?: Lock;
	constructor(parent?: Lock, locked?: number | boolean);
	/** the number of times this Lock is currently locked */
	get count(): number;
	/** the number of callbacks waiting for this Lock */
	get waiting(): number;
	/**
	 * Locks this lock, unlock the returned lock once you're done with this resource.
	 * @returns a new lock
	 */
	lock(): Lock;
	/** Unlocks this lock. */
	unlock(): Promise<void>;
	/** Alias of .unlock() */
	release(): Promise<void>;
	/** release lock after {delay=0} ms */
	release_async(delay?: number): void;
	/** Gets a promise which resolves when this lock is unlocked. */
	get promise(): Promise<void>;
	/** Will be called when the lock is unlocked. */
	set callback(callback: Function);
	/** Waits for this lock to be unlocked, then locks. */
	wait_and_lock(): Promise<Lock>;
	/**
	 * Attempt to lock synchronously (if not locked)
	 * @returns a Lock upon success, does not throw on failure
	 */
	try_lock_sync(): Lock | void;
	/** @returns `>= 1` if lock is locked, `0` otherwise */
	get locked(): number;
}
export default Lock;