Retention</a>,
    blockCall: @escaping <a href="https://developer.apple.com/documentation/swift/sendable?language=swift">@Sendable</a> <a href="../other-apis.html?swift#rbblockcallback">RbBlockCallback</a>
) throws -&gt; <a href="../types/rbobject13.html?swift">RbObject</a></code></pre>
  </div>



            </div>
            
  <h5>Parameters</h5>
  <table class="j2-param-table">
    <tbody>
      
      <tr>
        <td><code>symbol</code></td>
        <td><p>The symbol for the name of the method to c