constructor( node, parent = true ) {

		super();

		/**
		 * The node that should be cached.
		 *
		 * @type {Node}
		 */
		this.node = node;

		/**
		 * Whether this node refers to a shared parent cache or not.
		 *
		 * @type {boolean}
		 * @default true
		 */
		this.parent = parent;

		/**
		 * This flag can be used for type testing.
		 *
		 * @type {boolean}
		 * @readonly
		 * @default true
		 */
		this.isCacheNode = true;

	}
Constructs a new cache node.

@param {Node} node - The node that should be cached.
@param {boolean} [parent=true] - Whether this node refers to a shared parent cache or not.