/**
 * Converts `data` into a suitable `Uint8Array` representation.
 * When `data` is a `string`, it must be a hexadecimal string.
 * The hexadecimal string may optionally start with `0x`.
 *
 * When `data` is an `ArrayLike<number>`, it is converted to a `Uint8Array`.
 * If `data` is a `Uint8Array`, it is returned as-is.
 *
 * If `data` is a `string` and it is not a valid hexadecimal string,
 * it throws an `Error`.
 *
 * @param data the data to convert to `Uint8Array`
 * @returns the `Uint8Array` representation of `data`
 */
export declare function arrayify(data: Uint8Array | ArrayLike<number> | string): Uint8Array;
/**
 * Converts `data` into a hexadecimal string without the `0x` prefix.
 *
 * @param data the `Uint8Array` to convert to a hexadecimal string
 * @returns the hexadecimal string representation of `data`
 */
export declare function hexlify(data: Uint8Array): string;