title: Multiple inheritance in variadic template class & calling constructors
body: <p>Let's say I have this example:</p>
  
  <pre><code>//Two interfaces
  class InterfaceA {
  public:
      InterfaceA(int val);
  };
  
  class InterfaceB {
  public:
      InterfaceB(int val);
  };
  
  //Class with multiple inheritance
  template &lt;typename... Intefaces&gt;
  class Base : public Interfaces... {
  public:
      Base() : Interfaces(42) {}; // This is wrong
  }
  </code></pre>
  
  <p>How to call constructors of the "Interfaces" classes with a single argument?</p>