anchor.diff:  				empty-rank
   				empty-rank
   				(list 1 0 0 0 0 0 0 1)))))
  +(print (position-board (aref knight-positions 33)))
  +(print (position-board (make-bb (list 
  +				empty-rank
  +				empty-rank
  +				empty-rank
  +				empty-rank
  +				empty-rank
  +				empty-rank
  +				empty-rank
  +				(list 1 0 0 0 0 0 0 1)))))
  +(print (position-board (aref line-up 33)))
  
positive.code: 	       (mapcar #'make-bb (mapcar #'position-list-to-board-list king-moves-list))))
  (print (integer-length 4))
  (print (logxor 4 (ash 1 (- (integer-length 4) 1))))
  (print (position-list (make-bb (list 
  				empty-rank
  				empty-rank
  
negative.code: 	   (incf mj)))
      moves))
  
  (defun gen-diag-down-left (i j)
    (let ((moves))
      (let ((mi (+ i 1))
  	  (mj (- j 1)))
  