JSFiddle - React, Tailwind, and code Playground

HTML

<script src="http://cdnjs.cloudflare.com/ajax/libs/lodash.js/0.8.2/lodash.min.js"></script>

JavaScript

var a = ['a0'];
a[3] = 'a3';
_.each(a, console.log, console);
a.forEach(console.log, console);