title: Testing if property exists
body: <p>I read on <a href="http://www.php.net/manual/en/function.property-exists.php#97538" rel="noreferrer">php docs</a> that <code>isset()</code> is faster than <code>property_exists()</code> 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>