Value as the key
<p>I have an array like this:</p>

<pre><code>$options[0] = 1;
$options[1] = 2;
$options[2] = 3;
$options[3] = 'something';
</code></pre>

<p>How can I have the value of each array element put as the key, so the array looks like this:</p>

<pre><code>$options[1] = 1;
$options[2] = 2;
$options[3] = 3;
$options['something'] = 'something';
</code></pre>

<p>Is there a built in function for this?</p>
