title: Can I reference other properties during object declaration in JavaScript?
body: <p>I am trying to do something like this:</p>
  
  <pre><code>var obj = {
      a: 5,
      b: this.a + 1
  }
  </code></pre>
  
  <p>(instead of 5 there is a function which I don't want to execute twice that returns a number)</p>
  
  <p>I can rewrite it to assign <code>obj.b</code> later from <code>obj.a</code>, but can I do it right away during declaration?</p>