title: Javascript - Detecting defined variable as undefined
body: <p>For example:</p>
  
  <pre><code>var myObj = {
      yes: undefined
  }
  
  console.log(typeof myObj.yes === 'undefined') //--&gt; true
  console.log(typeof myObj.nop === 'undefined') //--&gt; true too
  </code></pre>
  
  <p>Is there a way to detect if myObj.nop is not defined as undefined ?</p>