JSFiddle - React, Tailwind, and code Playground

by Khalil Zhang

JavaScript

var obj2String = Object.prototype.toString;

var num1 = Number(1);
document.write('typeof num1 : ' + typeof num1 + '<br/>');
document.write('obj2String.call(num1): ' + obj2String.call(num1) + '<br/>');
document.write('num1  instanceof Number: ' + (num1 instanceof Number) + '<br />');
document.write('num1 instanceof Object: ' + (num1 instanceof Object) + '<br /><br />');

var num2 = new Number(2);
document.write('typeof num2 : ' + typeof num2 + '<br/>');
document.write('obj2String.call(num2): ' + obj2String.call(num2) + '<br/>');
document.write('num2 instanceof Number: ' + (num2 instanceof Number) + '<br />');
document.write('num2 instanceof Object: ' + (num2 instanceof Object) + '<br /><br />');


var obj1 = Object(1);
document.write('typeof obj1: ' + typeof obj1 + '<br/>');
document.write('obj2String.call(obj1): ' + obj2String.call(obj1) + '<br/>');
document.write('obj1 instanceof Number: ' + (obj1 instanceof Number) + '<br />');
document.write('obj1 instanceof Object: ' + (obj1 instanceof Object) + '<br /><br />');

var obj2 = new Object(2);
document.write('typeof obj2 : ' + typeof obj2 + '<br/>');
document.write('obj2String.call(obj2): ' + obj2String.call(obj2) + '<br/>');
document.write('obj2 instanceof Number: ' + (obj2 instanceof Number) + '<br />');
document.write('obj2 instanceof Object: ' + (obj2 instanceof Object) + '<br /><br />');

//if the value is a native ECMAScript object, do not create a new object but //simply return value.
var a = [];
document.write("a === new Object(a): " + (a === new Object(a)) + '<br/>');
document.write("a === Object(a): " + (a === Object(a)) + "<br/>");