 <span class="identifier">T</span><span class="special">&amp;</span> <span class="identifier">attr</span><span class="special">,</span> <span class="keyword">bool</span> <span class="identifier">full_match</span> <span class="special">=</span> <span class="keyword">true</span><span class="special">)</span>
<span class="special">{</span>
    <span class="keyword">using</span> <span class="identifier">boost</span><span class="special">::</span><span class="identifier">spirit</span><span class="special">::</sp