>quoted_string_class</span> <span class="special">{};</span>
    <span class="keyword">struct</span> <span class="identifier">person_class</span> <span class="special">:</span> <span class="identifier">x3</span><span class="special">::</span><span class="identifier">annotate_on_success</span> <span class="special">{};</span>
    <span class="keyword">struct</span> <span class="identifier">employee_class</span> <span class="special">:</span> <span class="identifier">error_handler</span><span class="special">