title: Regex extracts one symbol more than needed
body: <p>I need to extract number from string: </p>
  
  <pre><code>var ss = klase.match(/[col-lg-]\d+/);
  </code></pre>
  
  <p>However, it extracts <code>-1</code> for example instead of just <code>1</code>.</p>
  
  <p>Why it is so ?</p>
  
  <p>String example: <code>draggable ui-draggable ui-draggable-handle dragged col-lg-8</code></p>