Static variable inside template function

Question

In C++, if you define this function in header.hpp

void incAndShow()
{
  static int myStaticVar = 0;
  std::cout << ++myStaticVar << \" \" <<         


        

Answer 1

Templates are instantiated as needed, which means that compiler (linker as well in this case?) will make sure that you don't end up with multiple instances of the same template as well as only those instances of templates that you need - in your case only incAndShow<int>() is instantiated and nothing else (otherwise compiler would have to try to instantiate for every type which does not make sense).

So I assume that the same methods it uses to figure out for which type to instantiate template prevents it from instantiating twice for the same type e.g. only one instance of incAndShow<int>()

This is different from non template code.