="Caution">
<tr>
<td rowspan="2" align="center" valign="top" width="25"><img alt="[Caution]" src="../../../../images/caution.png"></td>
<th align="left">Caution</th>
</tr>
<tr><td align="left" valign="top"><p>
              The generator <code class="computeroutput"><span class="identifier">string</span><span class="special">(</span><span class="identifier">s</span><span class="special">)</span></code> up to version 2.4.1 of Spirit has
              an undocumented feature. Given argument <code class="compu