/** @hidden */
export declare function checkString(candidate: {}): boolean;
/** @hidden */
export declare function checkNumber(candidate: {}): boolean;
/**
 * Check if the given amount is valid.
 *
 * **Note:** a valid amount means that it can be embedded into a block `balance`.
 *
 * @param amount - The amount to check
 * @returns Valid
 */
export declare function checkAmount(amount: string): boolean;
/**
 * Check if the given seed is valid.
 *
 * **Note:** it only checks the format of the seed.
 *
 * @param seed - The seed to check
 * @returns Valid
 */
export declare function checkSeed(seed: string): boolean;
/**
 * Check if the given threshold is valid.
 *
 * **Note:** it only checks the format of the threshold.
 *
 * @param threshold - The threshold to check
 * @returns Valid
 */
export declare function checkThreshold(threshold: string): boolean;
/**
 * Check if the given index is valid.
 *
 * **Note:** it only checks the format of the index.
 *
 * @param index- The index to check
 * @returns Valid
 */
export declare function checkIndex(index: number): boolean;
/**
 * Check if the given hash is valid.
 *
 * **Note:** it only checks the format of the hash.
 *
 * @param hash - The hash to check
 * @returns Valid
 */
export declare function checkHash(hash: string): boolean;
/**
 * Check if the given public or secret key is valid.
 *
 * **Note:** it only checks the format of the key.
 * It does not check whether or not the key does exist on the network.
 *
 * @param key - The key to check
 * @returns Valid
 */
export declare function checkKey(key: string): boolean;
/**
 * Check if the given address is valid.
 *
 * **Note:** it checks the format and the checksum of the address.
 * It does not check whether or not the address does exist on the network.
 *
 * @param address - The address to check
 * @returns Valid
 */
export declare function checkAddress(address: string): boolean;
/**
 * Check if the given work is valid.
 *
 * **Note:** it only checks the format of the work, not its difficulty.
 *
 * @param work - The work to check
 * @returns Valid
 */
export declare function checkWork(work: string): boolean;
/**
 * Check if the given signature is valid.
 *
 * **Note:** it only checks the format of the signature.
 *
 * @param signature - The signature to check
 * @returns Valid
 */
export declare function checkSignature(signature: string): boolean;