JSFiddle - React, Tailwind, and code Playground

by Jon Kittell

HTML

<p id="message" onclick="write"></p>

JavaScript

function write(message) {
    document.getElementById('message').innerHTML += message + '<br/>';
}

var notAssigned;
write(notAssigned);

if (!notAssigned) {
    // write("undefined evaluates to false");
}

var person = {
    name: "Frank"
};

write("non-existent object property: " + person.age);