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var isNumber = require('./isNumber');
/** * Checks if `value` is `NaN`. * * **Note:** This method is based on * [`Number.isNaN`](https://mdn.io/Number/isNaN) and is not the same as * global [`isNaN`](https://mdn.io/isNaN) which returns `true` for * `undefined` and other non-number values. * * @static * @memberOf _ * @since 0.1.0 * @category Lang * @param {*} value The value to check. * @returns {boolean} Returns `true` if `value` is `NaN`, else `false`. * @example * * _.isNaN(NaN); * // => true * * _.isNaN(new Number(NaN)); * // => true * * isNaN(undefined); * // => true * * _.isNaN(undefined); * // => false */function isNaN(value) {  // An `NaN` primitive is the only value that is not equal to itself.  // Perform the `toStringTag` check first to avoid errors with some  // ActiveX objects in IE.  return isNumber(value) && value != +value;}
module.exports = isNaN;