#include <iostream>
using namespace std;


template <typename T> class Stack {
  typedef typename T::ThisDoesntExist StaticAssert; // T::NotExisting doesn't exist at all!
};


void f1(Stack<char>); // No instantiation, compiles

class Exercise {
  //Stack<double> &rsd; // No instantiation, compiles (references don't need instantiation, are similar to pointers in this)

  Stack<int>    si; // Instantiation! Doesn't compile!!
};


int main(){

  Stack<char> *sc; // No Instantiation, this compiles successfully since a pointer doesn't need instantiation

  //f1(*sc); // Instantiation of char! Doesn't compile!!

  //int iObj = sizeof(Stack< std::string >); // Instantiation of std::string, doesn't compile!!

}