title: How to get canvas widget name from command?
body: <p>I try to make popup menus that are in part defined by the widget that it was opened on. I can't seem to find a way to find which widget the menu is opened on. For example:</p>
  
  <pre><code>.f.canvas bind all &lt;3&gt; {
    puts stderr "%W just gives me '.f.canvas'"
  }
  </code></pre>
  
  <p>The widget name would be used for lookup in another table to change properties of the object related to the specific widget.</p>