import type { Union } from 'ts-toolbelt';
/**
 * This method is like `defaults` except that it recursively assigns
 * default properties.
 *
 * **Note:** This method mutates `object`.
 *
 * @param object The destination object.
 * @param sources The source objects.
 * @return Returns `object`.
 * @example
 *
 * defaultsDeep({ 'a': { 'b': 2 } }, { 'a': { 'b': 1, 'c': 3 } })
 * // => { 'a': { 'b': 2, 'c': 3 } }
 */
export declare const defaultsDeep: <T extends object, S extends object[]>(object: T, ...sources: S) => T & Union.IntersectOf<S[number]>;