e.
            It must have a non-throwing destructor.
          </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. Default is default_user_allocator_new_delete. See __<a class="link" href="pooling.html#boost_pool.pool.pooling.user_allocator" title="The UserAllocator Concept">UserAllocator</a>
            for details.
          </p>
<p>
            <span 