ord">private</span><span class="special">:</span>
    <span class="keyword">static</span> <span class="identifier">pool</span><span class="special">&lt;</span><span class="identifier">size_type</span><span class="special">&gt;</span> <span class="identifier">p</span><span class="special">;</span> <span class="comment">// exposition only!</span>

    <span class="identifier">singleton_pool</span><span class="special">();</span>

  <span class="keyword">public</span><span class="special">:</span>
    <span cl