JSFiddle - React, Tailwind, and code Playground

HTML

Result:
<p id="output"></p>

JavaScript

function log(x)
{
    $("#output").append(x + '<br />');
}

var myGlobal = "This is global.";
(function () {
    log('Before declaration: ' + myGlobal);
    var myGlobal = "This is local.";
    log('After declaration: ' + myGlobal);
})();