lementation_defined.allocator_type"></a><span class="identifier">allocator_type</span><span class="special">;</span>     
  <span class="keyword">typedef</span> <span class="identifier">base_maker</span><span class="special">::</span><span class="identifier">node_type</span>           <a name="boost.heap.skew_heap.implementation_defined.node"></a><span class="identifier">node</span><span class="special">;</span>               
  <span class="keyword">typedef</span> <span class="identifier">allocator_type</s