title: Print the contents of a hash in insertion order
body: <p>I have the following script</p>
  
  <pre><code>my %hash = (
               'ev2'  =&gt; 'aaaa',
               'ev1' =&gt; 'bbbb'
             );   
  
  for my $key (sort keys %hash) {
     print $key , '-' , $hash{$key},  "\n";
  } 
  </code></pre>
  
  <p>that prints </p>
  
  <pre><code>ev1 - bbbb
  ev2 - aaaa
  </code></pre>
  
  <p>I want to print the elements in the order they were added to the hash.</p>
  
  <pre><code>ev2 - aaaa  
  ev1 - bbbb
  </code></pre>
  
  <p>How can I do this?</p>