/** Recursive object extending. */
declare function deepExtend<T extends object>(target: T): T;
declare function deepExtend<T extends object, U extends object>(target: T, source: U): T & U;
declare function deepExtend<T extends object, U extends object, V extends object>(
    target: T,
    source1: U,
    source2: V,
): T & U & V;
declare function deepExtend<T extends object, U extends object, V extends object, W extends object>(
    target: T,
    source1: U,
    source2: V,
    source3: W,
): T & U & V & W;
declare function deepExtend(target: object, ...sources: object[]): object;
declare namespace deepExtend {}
export = deepExtend;