ul>
<li>(no prefix) - Locate the required controller on the current element. Throw an error if not found.</li>
<li><code>?</code> - Attempt to locate the required controller or pass <code>null</code> to the <code>link</code> fn if not found.</li>
<li><code>^</code> - Locate the required controller by searching the element and its parents. Throw an error if not found.</li>
<li><code>^^</code> - Locate the required controller by searching the element&#39;s parents. Throw an error if not found.</li>
<li><code>