ype</span><span class="special">::</span><span class="identifier">value_type</span> <span class="special">&gt;</span> <span class="special">&amp;</span><span class="special">,</span> 
                      <span class="identifier">Ptree</span> <span class="special">&amp;</span><span class="special">,</span> <span class="keyword">int</span> <span class="special">=</span> <span class="number">0</span><span class="special">)</span><span class="special">;</span>
      <span class="keyword">template</span><span 