title: How do I get window number from CFTypeRef in cocoa?
body: <pre><code>CFTypeRef focusedWindow;
  AXUIElementCopyAttributeValue(
          frontMostApp, kAXFocusedWindowAttribute, (CFTypeRef *)&amp;focusedWindow
  );
  </code></pre>
  
  <p>in this case, How do I get window number from <code>focusedWindow</code>?</p>
  
  <p>Window number is like <code>[[NSApp mainWindow] windowNumber]</code></p>