></span>: Nothing. </p>
</li>
<li class="listitem">
<pre class="literallayout"><a name="idp65844208-bb"></a><span class="identifier">unordered_set_base_hook</span><span class="special">(</span><span class="keyword">const</span> <a class="link" href="unordered_set_base_hook.html" title="Class template unordered_set_base_hook">unordered_set_base_hook</a> <span class="special">&amp;</span><span class="special">)</span><span class="special">;</span></pre>
<p><span class="bold"><strong>Effects</strong></span>: I