title: Optional named parameter in Play Framework
body: <p>In Rails I can say:</p>
  
  <pre><code>get 'path1/:path2/(:path3)' =&gt; "controller#action"
  </code></pre>
  
  <p>where <code>path3</code> is an optional <strong>named</strong> parameter and there is a slash before it. In Play Framework I only found the way to do something like this but only for parameters with <code>?</code>.</p>
  
  <p>How do I do that in Play Framework?</p>