Passing any function as template parameter

Question

I want to pass a function value as a template parameter to a function. Currently the best I managed to do is :

template< typename F, F f >         


        

Answer 1

You need to make a typedef for whatever function type you want to pass as a pointer, like this:

typedef int (*MyFunctionType)(int);

template 
ReturnType callFunction(FunctionTypedef functionPointer, ParameterType i)
{
  static MyFunctionType myFunctionPointer = functionPointer;
  return (*functionPointer)(i);
}
int myFunction(int i)
{
}


int main()
{
  int i = 7;
  MyFunctionType myFunctionPointer = myFunction;
  return callFunction(myFunctionPointer, i);
}

Edit: If you want to store these arbitrarily typed function pointers, then make a base class with a virtual "call function" function, and a templated derived class that implements this function.