Create a class based on user input
<p>It's not safe to require $input . '.php'. To then institate a class. How can I make it secure, without needing to use say a whitelist of classes that can be inistiated.</p>

<p>Ex 1. (bad code).</p>

<pre><code>&lt;?php

$input = $_GET['controller'];

require $input . '.php';

new $input;

?&gt;
</code></pre>
