wildcard function pointer non-type template parameter

Question

Templates can take non-type function pointer parameters, but there is a problem if all possible function pointer parameters are accepted, example:

void dummy()
{         


        

Answer 1

If you know the signature of the function you wish to call (and surely you do), can't you do

template<void F()>
void proxy()
{
    F();
}

void dummy() {}

int main()
{
    proxy<dummy>();
}

Answer 2

A better solution for your particular problem would be to simply take only the function type as a template argument and the item as an ordinary function argument. You can also use type deduction instead of explicitly specifying which argument types are used:

void dummy()
{
}

template <typename FT>
void proxy(FT fp)
{
  fp();
}

int main()
{
  proxy(fp);

  return 0;
}