title: In Perl, why does copying a weak reference create a normal, strong, reference?
body: <p><a href="http://search.cpan.org/perldoc/Scalar::Util::weaken" rel="noreferrer">Scalar::Util::weaken</a> says:</p>
  
  <blockquote>
    <p>NOTE: Copying a weak reference creates a normal, strong, reference.</p>
  </blockquote>
  
  <p>I can't understand why Perl handle it this way. In my applications, I use 
  <code>weaken</code> to break cycles. Sometimes i have to weaken references that would be already weak if Perl wouldn't act this way.</p>