>tail_variate</span><span class="special">&lt;</span> <span class="identifier">VariateType</span><span class="special">,</span> <span class="identifier">VariateTag</span><span class="special">,</span> <span class="identifier">LeftRight</span> <span class="special">&gt;</span><span class="special">&gt;</span> <span class="special">:</span>
  <span class="keyword">public</span> <span class="identifier">boost</span><span class="special">::</span><span class="identifier">accumulators</span><span class="special"