'use strict';

var define = require('define-properties');
var getPolyfill = require('./polyfill');

/* http://www.ecma-international.org/ecma-262/6.0/#sec-number.isnan */

module.exports = function shimNumberIsNaN() {
	var polyfill = getPolyfill();
	define(Number, { isNaN: polyfill }, { isNaN: function () { return Number.isNaN !== polyfill; } });
	return polyfill;
};