JSFiddle - React, Tailwind, and code Playground

by Bhesh Gurung

JavaScript

function isDefined(varName) {     
    if(typeof window[varName] === 'undefined') {         
        return true;     
    }     
    return false; 
}  

var hello1; 
var hello2 = '';  

alert('hello1' + isDefined('hello1')); 
alert('hello2' + isDefined('hello2')); 
alert('hello3' + isDefined('hello3'));