Function Returning Itself

Question

Is it possible to declare some function type func_t which returns that type, func_t?

In other words, is it possible for a function to retur

Answer 1

Assume the function definition

T f(void)
{
  return &f;
}

f() returns a value of type T, but the type of the expression &f is "pointer to function returning T". It doesn't matter what T is, the expression &f will always be of a different, incompatible type T (*)(void). Even if T is a pointer-to-function type such as Q (*)(void), the expression &f will wind up being "pointer-to-function-returning-pointer-to-function", or Q (*(*)(void))(void).

If T is an integral type that's large enough to hold a function pointer value and conversion from T (*)(void) to T and back to T (*)(void) is meaningful on your platform, you might be able to get away with something like

T f(void)
{ 
  return (T) &f;
}

but I can think of at least a couple of situations where that won't work at all. And honestly, its utility would be extremely limited compared to using something like a lookup table.

C just wasn't designed to treat functions like any other data item, and pointers to functions aren't interchangeable with pointers to object types.