l">;</span>
  <span class="emphasis"><em><span class="identifier">unspecified</span></em></span> <a class="link" href="flat_map.html#idp36252032-bb"><span class="keyword">operator</span><span class="special">[</span><span class="special">]</span></a><span class="special">(</span><span class="keyword">const</span> <span class="identifier">key_type</span> <span class="special">&amp;</span><span class="special">)</span><span class="special">;</span>
<span class="special">}</span><span class="special">;</span><