an><span class="identifier">invalid_argument</span></code>
                    </p>
                  </td>
<td>
                    <p>
                      <code class="computeroutput"><span class="special">!</span> <span class="keyword">this</span><span class="special">-&gt;</span><span class="identifier">is_array</span><span class="special">()</span></code>
                    </p>
                  </td>
</tr></tbody>
</table></div>
</div>
<table xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/do