import type { FieldKey, FieldOptions } from 'nukak/type';
export declare function clone<T>(value: T): T;
export declare function hasKeys<T>(obj: T): boolean;
export declare function getKeys<T>(obj: T): string[];
export declare function getFieldKeys<E>(fields: {
    [K in FieldKey<E>]?: FieldOptions;
}): FieldKey<E>[];