If you want to be able to implement nullary functions, then you need a nullary function to begin with. You are not really implementing anything besides maybe ne

If you want to be able to implement nullary functions, then you need a nullary function to begin with. You are not really implementing anything besides maybe negating the constant you got. You would also have to extend { AND, NOT } with a constant. The best you could do would change from one binary function to one binary function and a constant.