ss="link" href="../child_c.html" title="Function child_c">proto::child_c</a><span class="special">&lt;</span><span class="number">0</span><span class="special">&gt;</span><span class="special">(</span><span class="identifier">expr</span><span class="special">)</span><span class="special">,</span> <span class="special">...</span> <a class="link" href="../child_c.html" title="Function child_c">proto::child_c</a><span class="special">&lt;</span><span class="identifier">N</span><span class="special">&gt;</span>