title: Check if a field/propertry exists in a variable of type object
body: <p>I am using Zend_Search_Lucene, to index my website. My site indexes are not entirely similar. Some have, few fields, and some have many fields. I am trying to create a similar index through different types of table, that's why i am encountering this kind of error.</p>
  
  <p>Now, when I display the result. I call some fields, which are not present in all the result which generates the error. i tried to check it with <code>isset</code> but it seems it totally skips the row.</p>
  
  <pre><code>foreach ($hits as $hit) {
      $content .= '&lt;div class="searchResult"&gt;';
        $content .= '&lt;h2&gt;';           
          $title = array();
          if(isset($hit -&gt; name)) $title[] = $hit -&gt; name;
          if(isset($hit -&gt; title)) $title[] = $hit -&gt; title;
              // This is the part where i get fatal error.
          $content .= implode(" &amp;raquo; ",$title);
        $content .= '&lt;/h2&gt;';
        $content .= '&lt;p&gt;'.$this-&gt;content.'&lt;/p&gt;';
      $content .= '&lt;/div&gt;';
  }
  </code></pre>
  
  <p>How to check if there is anything such as <code>$hit -&gt; name</code> is present in <code>$hit</code></p>