JSFiddle - React, Tailwind, and code Playground

by Sean Cannon

HTML

<div class="title">
            <h1>
                This is a Test Environment for JavaScript
            </h1>
            <h2 id="Display">
                *Null*
            </h2>
        </div>
        <div class = "body">
            <div class="buttons">
                <div class = "row1">
                    <button onclick = "calc.addNum(1)"> 1</button>
                    <button onclick = "calc.addNum(2)"> 2</button>
                    <button onclick = "calc.addNum(3)"> 3</button>
                    <button onclick = "calc.add()"> +</button>
                </div>
                <div class = "row2">    
                    <button onclick = "calc.addNum(4)"> 4</button>
                    <button onclick = "calc.addNum(5)"> 5</button>
                    <button onclick = "calc.addNum(6)"> 6</button>
                    <button onclick = "calc.subtract()"> -</button>
                </div>
                <div class = "row3">
                    <button onclick = "calc.addNum(7)"> 7</button>
                    <button onclick = "calc.addNum(8)"> 8</button>
                    <button onclick = "calc.addNum(9)"> 9</button>
                    <button onclick = "calc.multiply()"> *</button>
                </div>
                <div class = "row4">
                    <button onclick = "calc.addNum(0)"> 0</button>
                    <button onclick = "calc.divide()"> /</button>
                    <button onclick = "calc.calculate()"> =</button>
                </div>
            </div>
         </div>

    <script>
        var calc = {
    first     : undefined,
    operator  : null,
    second    : undefined,
    result    : undefined
    Displayer : document.getElementById("display")
};
        calc.addNum = function(number)
        {
            alert(number);
            if(operator == null)
            {
                this.first = this.first.concat(number);
            }
            else
            {
                this.second =...