s a constructor parameter to the underlying
            pool. Must be greater than 0.
          </p>
<p>
            <span class="emphasis"><em>UserAllocator</em></span>
          </p>
<p>
            Defines the method that the underlying pool will use to allocate memory
            from the system. See User Allocators for details.
          </p>
<p>
            <span class="bold"><strong>Example:</strong></span> struct MyPoolTag { };
          </p>
<pre class="programlisting"><span class="keyword">typedef