((moving-rectangle player)
(standing-rectangle door)
(collision collision))
-
- (cond ((find (dungeon standing-rectangle) (keys moving-rectangle))
+ (cond ((find-if #'(lambda (x) (string= x (dungeon standing-rectangle))) (keys moving-rectangle))
(setf (keys moving-rectangle) (delete (dungeon standing-rectangle) (keys moving-rectangle) :count 1))
(setf (visible standing-rectangle) nil)
(setf (active standing-rectangle) nil)