lass="keyword">template</span><span class="special">&lt;</span><span class="keyword">typename</span> <span class="identifier">U1</span><span class="special">,</span> <span class="keyword">typename</span> <span class="identifier">U2</span><span class="special">,</span> <span class="special">...,</span> <span class="keyword">typename</span> <span class="identifier">UN</span><span class="special">&gt;</span>
<span class="identifier">tuple</span><span class="special">(</span><span class="keyword">const</span> <