e</span><span class="special">()-&gt;</span><span class="identifier">next</span><span class="special">();</span> <span class="special">}</span>
<span class="special">};</span>
</pre>
<p>
          Note the use of <code class="computeroutput"><span class="identifier">node_iter</span><span class="special">::</span><span class="identifier">iterator_adaptor_</span></code>
          here: because <code class="computeroutput"><span class="identifier">iterator_adaptor</span></code>
          defines a nested <code