/**
 * Search node matching the predicate on the current depth prior to moving to the next depth level
 *
 * @param root Tree root
 * @param predicate Search condition for the target tree node
 * @returns Matching node and a tree depth where this node was found
 */
export declare function breadthFirstSearch<T extends TreeNode>(root: T, predicate: (current: TreeNode | any) => boolean, depth?: number): BreadthFirstResult<T>;
/**
 * Breadth-first tree node
 */
export declare type TreeNode = {
    child?: TreeNode[];
} & Record<any, any>;
/**
 * Bredth-first search result
 */
export interface BreadthFirstResult<T> {
    /**
     * Matching node
     */
    node: T;
    /**
     * Tree depth where this node was found
     */
    depth: number;
}