export declare function randomString(keys?: number): {
    error: null;
    result: string;
};
export declare function generateSecureRandomPin(length?: number): Promise<{
    error: string | null;
    result: string | null;
}>;
export declare function generateSecureRandomBase64(): Promise<{
    error: string | null;
    result: string | null;
}>;
export declare function randomCrockford(keys?: number): {
    error: null;
    result: string;
};