ve_constructible</span><span class="special">&lt;</span> <span class="identifier">channel_attribute</span> <span class="special">&gt;</span><span class="special">::</span><span class="identifier">value</span><span class="special">)</span><span class="special">)</span><span class="special">;</span>
  <span class="keyword">template</span><span class="special">&lt;</span><span class="keyword">typename</span> ArgsT<span class="special">&gt;</span> <span class="keyword">explicit</span> <a class="link" href="basi