export declare function removeFallback<Prev, Next extends Prev>(prev: Prev[], next: Prev[], fallback: Next[]): (Prev & Next)[];
export declare function removeFallback<Prev, Next extends Prev>(prev: Prev, next: Prev, fallback: Next): Prev & Next;
export declare function mergeFallback<Prev, Next extends Prev>(prev: Prev[], fallback: Next[]): (Prev & Next)[];
export declare function mergeFallback<Prev, Next extends Prev>(prev: Prev, fallback: Next): Prev & Next;