title: Remove leading zeroes but not all zeroes
body: <p>How can I remove all the leading zeroes but leave a final zero if the value only contains zeroes?</p>
  
  <p>for example:</p>
  
  <pre><code>my $number = "0000";
  </code></pre>
  
  <p>I would like to have:</p>
  
  <pre><code>my $number = "0";
  </code></pre>
  
  <p>I tried:</p>
  
  <pre><code>$number =~ s/^0*//; 
  </code></pre>
  
  <p>but this of course removes all the zeroes in this case.</p>