title: C++ typedef to variadic template parameter
body: <p>I want to typedef a variadic template parameter like the attached code shows. It is possible to achive that?</p>
  
  <pre><code>template &lt;typename... T&gt;
  class Test
  {
  public:
      typedef T Arg;
  };
  
  template &lt;typename T&gt;
  class X
  {
  public:
      X(T::Arg arg);
  };
  </code></pre>