ss="identifier">geo</span><span class="special">::</span><span class="identifier">linear_tag</span><span class="special">,</span> <span class="identifier">geo</span><span class="special">::</span><span class="identifier">areal_tag</span><span class="special">&gt;::</span><span class="identifier">type</span> <span class="identifier">base_tag</span><span class="special">;</span>

    <span class="identifier">std</span><span class="special">::</span><span class="identifier">cout</span> <span class="special">&l