ted value type. </span>

  <span class="comment">// member classes/structs/unions</span>

  <span class="comment">// Attribute factory implementation.</span>

  <span class="keyword">struct</span> <a class="link" href="basic_clock/impl.html" title="Struct impl">impl</a> <span class="special">:</span> <span class="keyword">public</span> <span class="identifier">attribute</span><span class="special">::</span><span class="identifier">impl</span> <span class="special">{</span>

    <span class="comment">// <a c