 <span class="special">&gt;</span><span class="special">,</span> <span class="identifier">metadata_type</span> <span class="special">=</span> <span class="special">{</span><span class="special">}</span><span class="special">,</span> 
             <span class="identifier">allocator_type</span> <span class="special">=</span> <span class="special">{</span><span class="special">}</span><span class="special">)</span><span class="special">;</span>
  <a class="link" href="category.html#idm14284-bb"><span class="id