Question

In C++ I’m trying to make a simple state machine for a game, based on classes.

stateMan.setState<mainMenuState>();

I have a class with the declaration as:

class stateManager
{
  ...
  template <class T>
  void setState(void);
}

And the test code as:

template <class T>
void stateManager::setState<T>(void)
{
  T* blah = new T;
  delete blah;
}

And obviously this doesn’t work since function template partial specialization ‘setState<T>’ is not allowed.

Would there be a better way to do this besides doing it non-OO?

Answer 1

The definition of the member function template should be this:

template <class T>
void stateManager::setState(void)
{
   //...
}

That is, it should be simply setState instead of setState<T>. The latter syntax is used in function template specialization. Since T is a type parameter, the specialization would be considered as function partial template specialization which is not allowed.