Abstract/Base struct in C++?

Question

I'm making a chess game and I would like to have an array of pieces.

If I'm correct, in Java you can have an abstract Piece class and have King or Queen extend that class. If I were to make an array of Pieces I could place a King piece somewhere in that array and a Queen piece at another spot because both King and Queen extend Piece.

Is there any way to do that with structures in C++?

Answer 1

Yes. You can create an abstract base class in C++. Simply set one or more of the methods to be pure virtual:

class Piece {
    public:
        Piece ();
        virtual ~Piece ();
        virtual void SomeMethod () = 0;  // This method is not implemented in the base class, making it a pure virtual method. Subclasses must implement it
 };

You can then create sub-classes that implement the pure virtual methods

class King : public Piece {
    // ... the rest of the class definition
    virtual void SomeMethod (); // You need to actually implement this
};