lass="number">0</span></code>. In
        general, unless mandated by the Standard, Pool interfaces will always prefer
        to <code class="computeroutput"><span class="keyword">return</span> <span class="number">0</span></code>
        instead of throwing an exception.
      </p>
<h6>
<a name="boost_pool.pool.interfaces.h4"></a>
        <span class="phrase"><a name="boost_pool.pool.interfaces.ordered_versus_unordered"></a></span><a class="link" href="interfaces.html#boost_pool.pool.interfaces.ordered_ve