import type { FlatObject } from './types';
/**
 * Converting a nested structure to a flat one
 * Property names are transformed into a path {a: {b: 0}} => {'a.b': 0}
 * @param value {object|*} Source objects for conversion
 * @param separator
 * @param [path] {string} Base path for forming keys of the flat object. Used for recursion.
 * @param [clearUndefined] {boolean} Flag indicating whether to add undefined values to the result
 * @param [result] {object} Result - flat object. Passed by reference for recursion
 * @returns {{}}
 */
export declare function flat<V, S extends string = '.', P extends string = '', R = FlatObject<V, S>>(value: V, separator?: S, clearUndefined?: boolean, path?: P, result?: R): R;