JSFiddle - React, Tailwind, and code Playground

by basarat

HTML

<style>
    html, body {
        width: 100%;
        height: 100%;
        font-family:'Lucida Console';
        background: #575757;
        color: white;
        margin: 0px;
        overflow-y: hidden;
    }
    #console {
        width: 95%;
        height:90%;
        padding: 10px;
        overflow-y: auto;
    }
    #console div {
        margin-top: 5px;
    }
</style>
<div id="console"></div>
<script>
    var panel = document.querySelector("#console");
    var print = function(m) {
        var newline = document.createElement("div");
        newline.innerHTML = "&gt; " + JSON.stringify(m);
        this.panel.appendChild(newline);
    };
</script>

JavaScript

var adder = {
    increment: 1,
    add: function (value) {
        return this.increment + value;
    }
}

var oldAdd = adder.add;
adder.add = function(value){
    print('someone is calling with value: ' + value);
    return oldAdd.apply(adder,arguments);
}

// Intercepted!
adder.add(3);