Testing if property exists
<p>I read on <a href="http://www.php.net/manual/en/function.property-exists.php#97538">php docs</a> that isset is faster than property_exists and we should use a combination of both like</p>

<pre><code>if (isset($this-&gt;$fld) || property_exists($this, $fld)) { 
</code></pre>

<p>But why can't I just use isset then?</p>

<pre><code>if (isset($this-&gt;$fld)) {
</code></pre>
