Expression SFINAE to overload on type of passed function pointer

Question

In this example a function is passed to an implicitly instantiated function template.

// Function that will be passed as argument
int foo() { return 0; }

//         


        

Answer 1

The closest you can get is probably this:

struct sfoo
{
  template
  void operator() (args&&... a)
  { 
    foo(std::forward(a)...);
  }
};

and pass sfoo (or sfoo()) instead of foo around.

That is, create a function object type that encapsulates the entire overload set in the templatized operator().

Then instead of overload resolution over a template argument, which does not exist, you get a template instantiation over the same argument, which is OK.