interface BaseData<K> {
    id: K;
    parentId?: K;
    [key: string]: any;
}
declare class Node<K, T extends BaseData<K> = BaseData<K>> {
    readonly id: K;
    readonly parentId: K | undefined;
    readonly origin: T;
    parent: Node<K, T> | null;
    readonly children: Array<Node<K, T>>;
    constructor(data: T);
    addChildren(node: Node<K, T>): void;
}
/**
 * 数结构节点遍历
 * @example
 * ```typescript
 * const tree = new NodeTree<number>([
 *  { id: 1 },
 *  { id: 2, parentId: 1 },
 * ]);
 * const result = tree.travel(
 *  'up',
 *  tree.get(2)!,
 *  (node, result = 0) => {
 *    console.log(node);
 *    return result + node.id;
 * });
 * console.log(result);
 * // 3
 * ```
 */
export declare class NodeTree<K, T extends BaseData<K> = BaseData<K>> {
    private readonly cache;
    constructor(list?: T[]);
    private sort;
    get(id: K): Node<K, T> | undefined;
    apply(list: T[]): void;
    /**
     * 遍历节点方法
     * @param type - 向父节点 or 向子节点
     * @param node - 开始节点
     * @param handle - 遍历处理函数, 每个节点都会调用
     * @param data - 遍历处理函数的返回值
     * @returns
     */
    travel<R>(type: 'up' | 'down', node: Node<K, T>, handle: (node: Node<K, T>, result?: R) => R, data?: R): R;
}
export {};