:

    <blockquote><table border="0" cellpadding="1" cellspacing="0"
                 summary="Precedence of character class operators.">
      <tr><th>1&nbsp;&nbsp;&nbsp;&nbsp;</th>

          <td>Literal escape&nbsp;&nbsp;&nbsp;&nbsp;</td>
          <td><tt>\x</tt></td></tr>
     <tr><th>2&nbsp;&nbsp;&nbsp;&nbsp;</th>
          <td>Grouping</td>
          <td><tt>[...]</tt></td></tr>
     <tr><th>3&nbsp;&nbsp;&nbsp;&nbsp;</th>

          <td>Range</td>
          <td><tt>a-z</tt></td></tr>
      <tr><th>4&