al">&gt;</span> <span class="identifier">ConstRingIterator</span><span class="special">;</span>

<span class="keyword">namespace</span> <span class="identifier">boost</span>
<span class="special">{</span>
    <span class="comment">// Specialize metafunctions. We must include the range.hpp header.</span>
    <span class="comment">// We must open the 'boost' namespace.</span>

    <span class="keyword">template</span> <span class="special">&lt;&gt;</span>
    <span class="keyword">struct</span> <span class="i