title: C++ tuple of vectors, create tuple from elements by index
body: <p>I've got a template class, that has tuple, filled by vectors.</p>
  
  <pre><code>template&lt;typename ...Ts&gt;
  class MyClass
  {
      public:
          std::tuple&lt;std::vector&lt;Ts&gt;...&gt; vectors;
  };
  </code></pre>
  
  <p>I want to get new tuple filled by vectors element on the specified index.</p>
  
  <pre><code>template&lt;typename ...Ts&gt;
  class MyClass
  {
  public:
      std::tuple&lt;std::vector&lt;Ts&gt;...&gt; vectors;
  
      std::tuple&lt;Ts...&gt; elements(int index)
      {
          // How can I do this?
      }
  };
  </code></pre>
  
  <p>Is this even possible?</p>