Multiple subtyping

[Joel Christensen]

Hi,

Has anyone had much experience with multiple subtyping.

//Org: based on page 232 (6.13.1) in The D Programming Language book
//#save(); without storeShape does not work
import std.stdio;

class Shape {
        void shape() {
                writeln( "Shape" );
        }
}

class DataBase {
        void save() {
                writeln( "I'm the top - save" );
        }
}

class StoreShape : Shape {
        private class MyDataBase : DataBase {
                override void save() {
                        super.save();
                        writeln( "Data base: save" );
                }
        }
        
        private MyDataBase _store;
        alias _store this;
        
        this() {
                _store = this.new MyDataBase;
        }
}

void main() {
        auto storeShape = new StoreShape;
        
        with( storeShape ) {
                shape();
                storeShape.save(); //#save(); without storeShape. does not work
        }
}

- Joel