var _typeof = typeof Symbol === "function" && typeof Symbol.iterator === "symbol" ? function (obj) { return typeof obj; } : function (obj) { return obj && typeof Symbol === "function" && obj.constructor === Symbol && obj !== Symbol.prototype ? "symbol" : typeof obj; }; /** * Converts any value to string. * * @param {*} value * @returns {String} */ export function stringify(value) { var result = void 0; switch (typeof value === 'undefined' ? 'undefined' : _typeof(value)) { case 'string': case 'number': result = '' + value; break; case 'object': result = value === null ? '' : value.toString(); break; case 'undefined': result = ''; break; default: result = value.toString(); break; } return result; } /** * Checks if given variable is defined. * * @param {*} variable Variable to check. * @returns {Boolean} */ export function isDefined(variable) { return typeof variable !== 'undefined'; } /** * Checks if given variable is undefined. * * @param {*} variable Variable to check. * @returns {Boolean} */ export function isUndefined(variable) { return typeof variable === 'undefined'; } /** * Check if given variable is null, empty string or undefined. * * @param {*} variable Variable to check. * @returns {Boolean} */ export function isEmpty(variable) { return variable === null || variable === '' || isUndefined(variable); } /** * Check if given variable is a regular expression. * * @param {*} variable Variable to check. * @returns {Boolean} */ export function isRegExp(variable) { return Object.prototype.toString.call(variable) === '[object RegExp]'; }