                      <a name="boost.signals2.signal.group_compare_type"></a><span class="identifier">group_compare_type</span><span class="special">;</span>         
  <span class="keyword">typedef</span> <span class="identifier">SlotFunction</span>                                                                       <a name="boost.signals2.signal.slot_function_type"></a><span class="identifier">slot_function_type</span><span class="special">;</span>         
  <span class="keyword">typedef</span> <span c