// A slightly more realistic use of type selection.

#include <iostream>
#include <type_traits>

// Conditional is a syntactial embellishment of the application of underlying conditional template.
// We are using a template alias:
template<bool B, typename T, typename F>
using Conditional = typename std::conditional<B, T, F>::type;                       

constexpr long int LIMIT = 5000;

constexpr bool large(int n){
  return n > LIMIT;
}

int main() {
  using namespace std;

  const long int SZ = 1234;
  using FloatingPointT = Conditional<large(SZ),double,float>;                     // select type - float is selected in this 
                                                                                  // particular context.
  FloatingPointT x = 1234.5678;

  cout << "sizeof(double) = " << sizeof(double) << endl;                          // 8
  cout << "sizeof(float) = " << sizeof(float) << endl;                            // 4
  cout << "sizeof(FloatingPointT) = " << sizeof(FloatingPointT) << endl;          // 4

  return 0;
}