constructor( parent = null ) {

		/**
		 * The id of the cache.
		 *
		 * @type {number}
		 * @readonly
		 */
		this.id = _id$5 ++;

		/**
		 * A weak map for managing node data.
		 *
		 * @type {WeakMap<Node, Object>}
		 */
		this.nodesData = new WeakMap();

		/**
		 * Reference to a parent node cache.
		 *
		 * @type {?NodeCache}
		 * @default null
		 */
		this.parent = parent;

	}
Constructs a new node cache.

@param {?NodeCache} parent - A reference to a parent cache.