c++ - Trying to define types with variadic templates -

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I'm new to varied templates, so stay here with me.

I am trying to bring my dimensional analysis library to the 21st century and to C +11, I would like the ability to define a type of type, not an example, it is basically that What do I want to say: 

  Velocity_dimension = make_dimension & lt; 1, 0, -1, 0, 0, 0, 0>;   
 The result should be of the following:  
  velocity_dimension = std :: tuple & lt; Std :: ratio & lt; 1>, std :: ratio & lt; 0 & gt; , Std :: Ratio & lt; -1 & gt; std :: ratio & lt; 0>, std :: ratio & lt; 0>, std :: ratio & lt; 0>, std :: ratio & lt; 0 & gt; & Gt ;;   
 I am struggling to wrap my mind about varied templates and how to get the interface. I am trying to experiment with:  
  template & lt; Typename t, typename ... args & gt; Make_list = std :: tuple & lt; Using the Std :: Ratio & lt; T & gt;, make_list & lt; ARG & gt; ... & gt; & Gt; ;   
 I think that just tells me how much I do not understand how these things should work.  
  
 
 
 You want something that takes a number into a variable number of integers, not type, Therefore, the template parameter list should not contain  typename .  
 Similarly  std :: proportion & lt; T & gt; Template logic must be an integer in , no type.  
 Your recursive  make_list  will not work because you can not specialize in an alias template, so there is no way to end the recursive. You can do something like this with a class template and can provide partial expertise to finish the recurring, but there is no need to do this.  
 I think you want:  
  template & lt; int ... I & gt; Make_dimension = std :: tuple & lt; Using the std :: ratio, & lt; I & gt; ... & gt ;;   
 It packs a parameter pack of integers, then it returns the  std :: ratio  and wrapping a lot in the tubal. / P> 
 Packs expansion pattern here  std :: ratio  I> ...  which means that each element in the  i  parameter pack  I  to  std :: ratio  i> gt; , so if there is a pack then  1, 2, 3  then the extension is  std :: ratio & lt; 1>, std :: ratio & lt; 2>, std :: ratio & lt; 3 & gt;

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