D语言使用final和static函数的接口

import std.stdio;

// Base class
interface Shape {
   public:
      void setWidth(int w);
      void setHeight(int h);

      static void myfunction1() {
         writeln("This is a static method");
      }
      final void myfunction2() {
         writeln("This is a final method");
      }
}

// Derived class
class Rectangle: Shape {
   int width;
   int height; 

   public:
      void setWidth(int w) {
         width = w;
      }
      void setHeight(int h) {
         height = h;
      }
      int getArea() {
         return (width * height);
      }
}

void main() {
   Rectangle rect = new Rectangle();

   rect.setWidth(5);
   rect.setHeight(7);

   // Print the area of the object.
   writeln("Total area: ", rect.getArea());
   rect.myfunction1();
   rect.myfunction2();
}