title: Set initial value of computed or supress the first evaluation
body: <p><strong>[This seems to be impossible. I will answer this question by myself later]</strong></p>
  
  <p>This question largely continues <a href="https://stackoverflow.com/questions/36036356/">my pervious one</a>. I use <a href="https://github.com/knockout/knockout/wiki/asynchronous-dependent-observables" rel="nofollow noreferrer">"async computed"</a> approach to refresh some parts of my page. Thanks to Michael Best I <a href="https://jsfiddle.net/mbest/bpr88bp3/2/" rel="nofollow noreferrer">solved issue</a> with updates of invisible parts of UI. But one annoying thing still here. How can I set initial (default) value to computed observable? I try to avoid multiple ajax calls during page load. Instead of it I embed json into page to load everything at once. Seems trivial (common)? But I can't supress first evaluation of my async computed. So ajax call will be made in any case.
  I could use this approach:</p>
  
  <pre><code>var isFirstEval = ko.observable(true);
  updateComputed = ko.pureComputed(function () {
      updateTrigger();
      if(isFirstEval()){
          isFirstEval(false);
          result(initialValue);
      }
      else
          result(evaluator.call(owner));
  });
  </code></pre>
  
  <p>But I face <em>the same</em> issue, as in the previous question: this computed will never subscribe on <code>evaluator</code> changes, because of <a href="http://knockoutjs.com/documentation/computed-dependency-tracking.html" rel="nofollow noreferrer">approach</a> knockout uses to reevaluate computed observables.
  The <a href="https://stackoverflow.com/a/15478429/3602201">suggestion</a> from similar question works because it checks for the first evaluation <em>after</em> <code>var value = self.product() * self.quantity();</code>. So the computed is always tracking <code>product</code> and <code>quantity</code>. I can't use this approach, because I can't call <code>evaluator</code> just to care about dependency as <code>evaluator</code> can make ajax call...</p>
  
  <p><strong>Does any way exists to supress the first evaluation of computed (or pure computed)? Or maybe way to set initial value?</strong>
  Any suggestions? Other workarounds?</p>