type_mapper_type</span><span class="special">;</span>      <span class="comment">// Mapper type for the event type. </span>
  <span class="keyword">typedef</span> <span class="emphasis"><em><span class="identifier">unspecified</span></em></span>                    <a name="boost.log.sinks.basic_event_log_backend.event_category_mapper_type"></a><span class="identifier">event_category_mapper_type</span><span class="special">;</span>  <span class="comment">// Mapper type for the event category. </span>
  <span