title: JQuery undefined object attribute still causes error even when not called
body: <p>I'm iterating through an api object and certain results do not have a specific attribute. I used this to make a placeholder if the attribute was missing:</p>
  
  <pre><code>if (data.track[i].image == undefined) {
      urlstring = "path/to/image";
  } else {
    urlstring = data.track[i].image[4][0];
  }
  </code></pre>
  
  <p>Unfortunately, I still get the error <code>Uncaught TypeError: Cannot read property '0' of undefined</code>, even though the else clause shouldn't trigger if the attribute is undefined.</p>