1 var isNumber = require('./isNumber');
4 * Checks if `value` is `NaN`.
6 * **Note:** This method is not the same as [`isNaN`](https://es5.github.io/#x15.1.2.4)
7 * which returns `true` for `undefined` and other non-numeric values.
12 * @param {*} value The value to check.
13 * @returns {boolean} Returns `true` if `value` is `NaN`, else `false`.
19 * _.isNaN(new Number(NaN));
28 function isNaN(value) {
29 // An `NaN` primitive is the only value that is not equal to itself.
30 // Perform the `toStringTag` check first to avoid errors with some ActiveX objects in IE.
31 return isNumber(value) && value != +value;
34 module.exports = isNaN;