/**
 * @ Author: Hanrea
 * @ version: 2023-03-06 13:14:21
 * @ copyright: Vecmat (c) - <hi(at)vecmat.com>
 */
import { IObjExt } from "./type.js";
/**
 * Checks if fn is a Class
 *
 * @param {IObjExt} obj
 * @returns {boolean}
 */
export declare function isClass(func: IObjExt): boolean;
/**
 * Checks if value is a string that contains only numbers
 *
 * @param {string} str
 * @returns {*}  {boolean}
 */
export declare function isNumberString(str: string): boolean;
/**
 * Checks if value is a standard JSON object,
 * must be a plain object or array
 *
 * @param {IObjExt} value
 * @returns {*}  {boolean}
 */
export declare function isJSONObj(value: IObjExt): boolean;
/**
 * Checks if value is a standard JSON string,
 * must be a string, and can be deserialized as an plain object or array
 *
 * @param {string} value
 * @returns {*}  {boolean}
 */
export declare function isJSONStr(value: string): boolean;
/**
 * Checks value is empty,
 * undefined, null, '', NaN, [], {} and any empty string(including spaces, tabs, formfeeds, etc.), returns true
 *
 * @param {*} value
 * @returns {*}  {boolean}
 */
export declare function isEmpty(value: any): boolean;
/**
 * Checks value is empty,
 * do not consider empty objects, empty arrays, spaces, tabs, form breaks, etc.
 *
 * @param {*} value
 * @returns {*}  {boolean}
 */
export declare function isTrueEmpty(value: any): boolean;