item">
            The dots in <code class="computeroutput"><span class="identifier">nan</span><span class="special">(...)</span></code>
            stand for an arbitrary string.
          </li>
<li class="listitem">
            <code class="computeroutput"><span class="identifier">one</span></code> stands for any string
            that <code class="computeroutput"><span class="identifier">std</span><span class="special">::</span><span class="identifier">num_get</span></code> parses as the number <code cl