ord">using</span> <span class="identifier">karma</span><span class="special">::</span><span class="identifier">double_</span><span class="special">;</span>
    <span class="keyword">using</span> <span class="identifier">karma</span><span class="special">::</span><span class="identifier">generate_delimited</span><span class="special">;</span>
    <span class="keyword">using</span> <span class="identifier">ascii</span><span class="special">::</span><span class="identifier">space</span><span class="special">;<