/**
 * 是否为有效的IP v4
 *
 * @param {string} val
 * @returns {boolean}
 * @example
 *
 * isValidIPV4('172.16.0.0');
 * // => true
 *
 * isValidIPV4('127.0.0.0');
 * // => true
 *
 */
export declare function isValidIPV4(val: string): boolean;