s="identifier">member</span></code>
      (if any). The constructor template is marked both <code class="computeroutput"><span class="keyword">constexpr</span></code>
      and <code class="computeroutput"><span class="keyword">explicit</span></code>. The former will
      be ignored if the corresponding inner constructor call (of <code class="computeroutput"><span class="identifier">member</span></code>)
      does not have the marker. The latter binds the other way; always taking effect,
      even when t