n class="identifier">http</span><span class="special">::</span><span class="identifier">basic_fields</span><span class="special">&lt;</span><span class="identifier">Allocator</span><span class="special">&gt;&gt;</span> <span class="keyword">const</span><span class="special">&amp;</span> <span class="identifier">req</span><span class="special">);</span>
</pre>
                          </td>
<td>
                            <p>
                              <span class="emphasis"><em>&lt;not available&gt;</e