class="keyword">public</span><span class="special">:</span>
  <span class="comment">// types</span>
  <span class="keyword">typedef</span> <span class="identifier">date_type</span><span class="special">::</span><span class="identifier">duration_type</span>                             <a name="boost.date_time.date_facet.duration_type"></a><span class="identifier">duration_type</span><span class="special">;</span>                
  <span class="keyword">typedef</span> <span class="identifier">date_type</span>