type Data = number | string | boolean | null | undefined | Date | Data[] | {
    [key: string]: Data;
};
type FormatKey = ((key: string) => string);
declare function deepClone<I extends Data, O extends Data = I>(value: I, formatKey?: FormatKey, refs?: Map<I, O>): O;
declare namespace deepClone {
    var formatKeys: typeof import("./deep-clone").formatKeys;
}
export default deepClone;
export declare function formatKeys(format: FormatKey): <I extends Data, O extends Data = I>(value: I) => O;