>&lt;&gt;::</span><span class="identifier">type</span></code>
                    is <code class="computeroutput"><span class="identifier">mpl</span><span class="special">::</span><span class="identifier">true_</span></code>
                  </p>
                </td>
<td>
                  <p>
                    Call the member function <code class="computeroutput"><span class="identifier">attr</span><span class="special">.</span><span class="identifier">clear</span><span class="special">()</span></code>