import { IndexPath } from './indexPath.js';
import { BaseOptions } from './options.js';
export type DiagramType = 'directory' | 'box';
export type DiagramOptions<T> = BaseOptions<T> & {
    getLabel: (node: T, indexPath: IndexPath) => string;
    type?: DiagramType;
    flattenSingleChildNodes?: boolean;
};
/**
 * Generate a diagram of the tree, as a string.
 */
export declare function diagram<T>(node: T, options: DiagramOptions<T>): string;