title: How to check if isset one after another until done
body: <p>I would like to test an <code>isset($_COOKIE['x'])</code> so that it loops until it founds a free spot.
  For example:</p>
  
  <pre><code>if(isset($_COOKIE['x']) {
      if(isset($_COOKIE['x2']) {
          if(isset($_COOKIE['x3']) {
              //etc
          }
      }
  } else {
      //do something
  }
  </code></pre>
  
  <p>And so on and so forth. How would this be possible to create? </p>