/** * Checks if the value is NaN. * * @param {unknown} value - The value to check. * @returns {value is typeof NaN} `true` if the value is NaN, `false` otherwise. * * @example * isNaN(NaN); // true * isNaN(0); // false * isNaN('NaN'); // false * isNaN(undefined); // false */ declare function isNaN(value: unknown): value is typeof NaN; export { isNaN };