anchor.diff:  
   
   
  +(defun find-shortest-path (from to successors)
  +  "
  +RETURN: The shortest path of length>0 from FROM to TO if it exists, or NIL.
  +"
  +  ;; breadth first search
  +  (loop
  +     :with processed = '()
  +     :for paths = (list (list from)) :then new-paths
  +     :for new-paths = (remove-if (lambda (head) (member head processed))
  +                                 (mapcan (lambda (path)
  +                                           (mapcar (lambda (new-node) (cons new-node path))
  +                                                   (funcall successors (first path))))
  +                                         paths)
  +                                 :key (function first))
  +     :for shortest-path = (find to new-paths :key (function first))
  +     :do (setf paths     (nconc paths new-paths)
  +               processed (nconc (delete-duplicates (mapcar (function first) new-paths)) processed))
  +     :until (or shortest-path (endp new-paths))
  +     :finally (return (reverse shortest-path))))
  +
  +
  +(defun find-cycles (objects successors)
  +  (remove nil (mapcar (lambda (cycle) (find-shortest-path cycle cycle successors)) objects)))
  +
  +(defun print-cycle (path)
  +  (format t "~%There is a cycle going ~%from ~A"  (first path))
  +  (dolist (node (rest path))
  +    (format t "~%  to ~A" node))
  +  (format t " !!!~%"))
  +
  +;; (mapc (function print-cycle) (find-cycles (list-all-packages)
  +;;                                           (function package-use-list)))
   
   
   
  
positive.code:       ((>= index (array-dimension vector 0)))
      (setf (aref vector index) (funcall constructor index)))
    vector)
  
  
  (defun undisplace-array (array)
  
negative.code:    "DISTINCT-FLOAT-TYPES" "FLOAT-TYPECASE" "FLOAT-CTYPECASE" "FLOAT-ETYPECASE"
     "+EPSILON" "-EPSILON"
     ;; 14 - CONSES
     "MAXIMIZE" "TOPOLOGICAL-SORT" "TRANSITIVE-CLOSURE" 
     "COMPUTE-CLOSURE" ; deprecated, renamed to transitive-closure
     "FIND-CYCLES" "FIND-SHORTEST-PATH"
     ;; 15 - ARRAYS
     "VECTOR-INIT" "UNDISPLACE-ARRAY" "DICHOTOMY-SEARCH"
     ;; 16 - STRINGS
  