d</span><span class="special">(</span><span class="identifier">i</span><span class="special">));</span>
      <span class="identifier">assert</span><span class="special">(</span><span class="identifier">omap</span><span class="special">.</span><span class="identifier">equal_range</span><span class="special">(</span><span class="identifier">i</span><span class="special">).</span><span class="identifier">first</span> <span class="special">!=</span> <span class="identifier">omap</span><span class="special">.</