<span class="identifier">iterator_adaptor</span><span class="special">(</span><span class="identifier">Base</span> <span class="keyword">const</span><span class="special">&amp;</span> <span class="identifier">iter</span><span class="special">);</span>
    <span class="keyword">typedef</span> <span class="identifier">Base</span> <span class="identifier">base_type</span><span class="special">;</span>
    <span class="identifier">Base</span> <span class="keyword">const</span><span class="special">&amp;</span> 