"left">Note</th>
</tr>
<tr><td align="left" valign="top"><p>
              Starting with <a href="http://boost-spirit.com" target="_top">Spirit</a> V2.5
              (distributed with Boost V1.47) the placeholder <code class="computeroutput"><span class="identifier">_val</span></code>
              can be used in semantic actions attached to top level generator components.
              In this case <code class="computeroutput"><span class="identifier">_val</span></code> refers
              to the supplie