kitchensink/examples/node_modules/is-number-object/index.js

Dispatch's awesome components and style guide

'use strict';

var numToStr = Number.prototype.toString;
var tryNumberObject = function tryNumberObject(value) {
	try {
		numToStr.call(value);
		return true;
	} catch (e) {
		return false;
	}
};
var toStr = Object.prototype.toString;
var numClass = '[object Number]';
var hasToStringTag = typeof Symbol === 'function' && typeof Symbol.toStringTag === 'symbol';

module.exports = function isNumberObject(value) {
	if (typeof value === 'number') { return true; }
	if (typeof value !== 'object') { return false; }
	return hasToStringTag ? tryNumberObject(value) : toStr.call(value) === numClass;
};