C64-dev/newLang/tests/semantic/interfaces.n8

interface Shape
  method area() as word
  method scale(f as byte) as word
  method name() as char
end interface

interface Named
  method label() as char
  method show()
end interface

class Box implements Shape, Named, Display
  public method area() as word
    return 1
  end method
  public method scale(f as byte) as word
    return f
  end method
  public method name() as char
    return 'b'
  end method
  public method label() as char
    return 'l'
  end method
  public method show()
  end method
end class

interface Display
  method show()
end interface

program Main
end program