e for the implementation. </span>
  <span class="keyword">typedef</span> <span class="identifier">ImplSetT</span><span class="special">::</span><span class="identifier">key_type</span>                                           <a name="boost.icl.separate_interval_set.key_type"></a><span class="identifier">key_type</span><span class="special">;</span>               <span class="comment">// key type of the implementing container </span>
  <span class="keyword">typedef</span> <span class="identifier">ImplSetT<