title: Knockout Computed not updating?
body: <p>I have the following code: </p>
  
  <pre><code>    self.isViewingFolder = ko.observable();
      self.isViewingSet = ko.observable();
      self.canEditFolder = ko.observable();
  
      self.isViewingFolder(ko.computed(function() {
          return router.activeRoute().moduleId == 'viewmodels/folder';
      }));
      self.isViewingSet(ko.computed(function () {
          return router.activeRoute().moduleId == 'viewmodels/set';
      }));
      self.canEditFolder(ko.computed(function() {
          return self.isViewingFolder() &amp;&amp; auth.isAuthenticated() &amp;&amp; !self.isPublicFolder()
      }));
  </code></pre>
  
  <p>isViewingFolder and isViewingSet are always updating as expected, though canEditFolder is only updating one time.  If I set canEditFolder to</p>
  
  <pre><code>canEditFolder(isViewingFolder())
  </code></pre>
  
  <p>Then it works, but I need logic in there so I'm using a computed observable.  Why wouldn't this be working?  </p>