nk" href="any.html#idp18638896-bb"><span class="identifier">swap</span></a><span class="special">(</span><a class="link" href="any.html" title="Class any">any</a> <span class="special">&amp;</span><span class="special">)</span><span class="special">;</span>

  <span class="comment">// <a class="link" href="any.html#idp18641472-bb">queries</a></span>
  <span class="keyword">bool</span> <a class="link" href="any.html#idp18641712-bb"><span class="identifier">empty</span></a><span class="special">(</span><span 