e conversion">conversion</a><span class="special">&lt;</span> <span class="identifier">Combiner</span> <span class="special">&gt;</span>   <a name="boost.icl.version.base_type"></a><span class="identifier">base_type</span><span class="special">;</span>    
  <span class="keyword">typedef</span> <span class="identifier">base_type</span><span class="special">::</span><span class="identifier">argument_type</span> <a name="boost.icl.version.argument_type"></a><span class="identifier">argument_type</span><span c