truct</span> <a class="link" href="complement_base.html" title="Struct template complement_base">complement_base</a> <span class="special">:</span>
  <span class="keyword">public</span> <span class="identifier">std</span><span class="special">::</span><span class="identifier">unary_function</span><span class="special">&lt;</span> <span class="identifier">Arg</span><span class="special">,</span> <span class="identifier">typeof</span><span class="special">(</span><span class="special">~</span><span class="ide