import type { ZeroXString, Signature, Payload } from './interface';
/**
 * RLP encode a payload into a digest
 * @param payload Payload to encode
 * @returns RLP encoded payload
 */
export declare function encodePayload(payload: Payload): Uint8Array<ArrayBufferLike>;
/**
 * Sign a message using the provided private key
 * @param payload Payload to sign
 * @param privateKey Private key to sign with
 * @returns Signature object with r, s, v components
 */
export declare function signMessage(payload: Payload, privateKey: ZeroXString): Promise<Signature>;
export declare function toHex(value: any): ZeroXString;