s="keyword">const</span> <span class="special">&amp;</span> <span class="identifier">a0</span><span class="special">,</span> <span class="identifier">A1</span> <span class="keyword">const</span> <span class="special">&amp;</span> <span class="identifier">a1</span><span class="special">,</span> <span class="identifier">A2</span> <span class="keyword">const</span> <span class="special">&amp;</span> <span class="identifier">a2</span><span class="special">)</span> <span class="keyword">const</span>
        <spa