Check if two types are of the same template

Question

I want to check if two types are of the same template. As an example I want the following snippet of code to return true because both objects are vectors despit

Answer 1

You can but it take a little of metaprog :

#include 
#include 
#include 
#include 

template  
struct CheckTypes_impl
{
    constexpr static bool check (Container1 , Container2 ) { return false; }
};

template <
    template  class Container1, class...  args1 ,  class...  args2 > 
struct CheckTypes_impl,Container1>
{
    constexpr static bool check (Container1 , Container1 ) { return true; }
};


template < 
        template  class Container1,
        class ... args1,
        template  class Container2,
        class ... args2
    > constexpr bool CheckTypes(Container1 c1, Container2 c2)
{
    return CheckTypes_impl,Container2>::check(c1,c2);
}

int main()
{
  std::vector v1(100,0);
  std::vector v2(100,0);
  std::set s;
  std::cout << CheckTypes(v1,v2)  << std::endl;
  std::cout << CheckTypes(v1,s)  << std::endl;
}

run : https://wandbox.org/permlink/OTuQfl7UBlbxgtCO

Update : You need " template class Container1, class..." because vector don't take 1 template param, but 2. In the general case you don't know how many default parameters will be used