title: Multiple Variadic Parameter Pack for Template Class
body: <p>I am using variadic parameter packs for policy based class design.</p>
  
  <pre><code>template &lt;APITypes APIType, class... Policies&gt;
  class IShader : public Policies... {
  
  };
  </code></pre>
  
  <p>Policies are defined when called or with defaults if none are specified. The problem comes when I need to add another variadic parameter pack:</p>
  
  <pre><code>template &lt;AttributeType... Attributes, APITypes APIType, class... Policies&gt;
  class IShader : public Policies... {
  
  };
  </code></pre>
  
  <p>This results in the error "Template parameter pack must be the last template parameter". I am planning to use the attribute pack to change the behaviour of at least one of the policies. But I can't work out how to get two variadic parameter packs in one template class.</p>