variadic_templated.cpp

#include <iostream>
#include <vector>

template <typename T>
T adder(T t) {
  return t;
}

template <typename T, typename ... Args>
T adder(T t, Args ... a) {
  std::cout << __PRETTY_FUNCTION__ << "\n";
  
  return t + adder(a...);
}

template <typename T, typename ... Is>
bool all_equal(Is ... values) {
  std::vector<T> v = { values...};
  if (v.size() <= 1) return true;
  for (int i = 1; i < v.size(); i++) {
    if (v[i] != v[i - 1]) return false;
  }
  return true;
}
template <typename T>
T map(T t) {
  return t;
}
template <typename ... T>
inline void variadic(T ... args) {
  auto list = { map(args)... };
  for (auto element : list) {
    std::cout << element << std::endl;
  }
}

template <typename Head, typename... Tail>
void print(Head const& head, Tail const&... tail){
  std::cout << head;
  if constexpr(sizeof...(tail) > 0) {
    std::cout << ", ";
    print(tail...);
  }
}

template <typename R, typename... T>
R sum(T... args) {
  return (args + ...);
}



int main(int argc, const char * argv[]) {

  std::cout << "Adder: " << adder(1, 2, 3, 4, 0) << std::endl;
  
  std::cout << "All equal: " << (all_equal<int>(1, 1, 1, 1, 1) ? "true" : "false") << std::endl;
  
  variadic(1, 2, 3, 4, 5);
  
  print(1, 2, 3, 4);
  
  std::cout << std::endl;
  
  std::cout << "Sum: " << sum<double>(3, 1 , 2, static_cast<float>(1.0), 10) << std::endl;


  return 0;
}