title: Is it possible to data-bind visible to the negation ("!") of a boolean ViewModel property?
body: <p>I'd like to use a property on my ViewModel to toggle which icon to display without creating a separate computed property of the inverse. Is this possible?</p>
  
  <pre class="lang-html prettyprint-override"><code>&lt;tbody data-bind="foreach: periods"&gt;
    &lt;tr&gt;
      &lt;td&gt;
        &lt;i class="icon-search" data-bind="visible: !charted, click: $parent.pie_it"&gt;&lt;/i&gt;
        &lt;i class="icon-remove" data-bind="visible: charted, click: $parent.pie_it"&gt;&lt;/i&gt;
      &lt;/td&gt;
    &lt;/tr&gt;
  &lt;/tbody&gt;
  </code></pre>
  
  <p>My ViewModel has a property periods which is an array of month, like this:</p>
  
  
  
  <pre><code>var month = function() {
      this.charted = ko.observable(false);
  };
  </code></pre>