title: AnyEvent timer question
body: <p>How could I make "visible" the timer? This example returns (intependent from the sleep-time always) <code>2</code> (I expected something similar to the sleep-time).</p>
  
  <pre><code>#!/usr/local/bin/perl
  use warnings;
  use 5.014;
  use AnyEvent;
  
  my $c = 0;
  my $cv = AnyEvent-&gt;condvar;
  
  my $once_per_second = AnyEvent-&gt;timer (
      after =&gt; 0,
      interval =&gt; 1,
      cb =&gt; sub {
          $c++;
          $cv-&gt;send;
      },
  );
  
  sleep 5;
  
  $cv-&gt;recv;
  
  say $c;
  </code></pre>