s="special">,</span> <span class="identifier">data</span><span class="special">&gt;</span>   <span class="identifier">m_</span><span class="special">;</span>

   <span class="keyword">friend</span> <span class="keyword">bool</span> <span class="keyword">operator</span> <span class="special">&lt;(</span><span class="keyword">const</span> <span class="identifier">data</span> <span class="special">&amp;</span><span class="identifier">l</span><span class="special">,</span> <span class="keyword">const</span> <sp