What is meaning of returning by reference reference `&&`
<blockquote>
  <p><strong>Possible Duplicate:</strong><br>
  <a href="http://stackoverflow.com/questions/5481539/what-does-t-mean-in-c11">What does T&amp;&amp; mean in C++11?</a>  </p>
</blockquote>



<p>The following code is NOT correct:</p>

<pre><code>widget&amp;&amp; f() {
   widget w;
   ...
   return w;
}
</code></pre>

<p>Question> What does <code>&amp;&amp;</code> mean? Can you give me a valid example that illustrates the usage of <code>&amp;&amp;</code>?</p>

<p>Note: I have searched <code>c++ return by reference reference</code> or <code>c++ &amp;&amp;</code> without getting any useful information.</p>
