anchor.diff:  (defclass* game ()
     ((game-map nil r)
      (players nil r)
  -   (head-player nil)
  +   (players-round nil)
      (turn-player nil)))
   
   (defgeneric read-map (file)
  
positive.code:    (territory (game-map container) key)))
  
  (defgeneric head-player (game)
    (:method ((game game)) (car (slot-value game 'head-player))))
  
  (defgeneric turn-player (game)
    (:method ((game game)) (car (slot-value game 'turn-player))))
  
  (defgeneric pass-head (game)
    (:method ((game game))
     (with-slots ((the-head-player head-player)) game
       (let ((head (pop the-head-player)))
         (setf the-head-player (nconc the-head-player (list head)))))
     (head-player game)))
  
  (defgeneric pass-turn (game)
    (:method ((game game))
     (with-slots ((the-turn-player turn-player)
                  (the-head-player head-player)) game
       (pop the-turn-player)
       (unless the-turn-player
         (setf the-turn-player (copy-list the-head-player))))
     (turn-player game)))
  
  (defmethod territories ((game game))
  
negative.code:             (t (read-map game-map))))
      (setf the-players (make-hash-table :test 'equalp))
      (dolist (name players) (add-player game name))  
      (setf the-players-round (copy-list players))
      (nconc the-players-round the-players-round)
      (setf the-turn-player the-players-round)))
  
  (defgeneric territory (container key)
    (:method ((container game-map) key)
  