#|
(defun equiv (list set)
  (let ((new-symb (gensym)))
    (dolist (elt set list)
      (setf list (substitute new-symb
                             elt
                             list)))))
|#

(defun equiv (list set)
  (let ((new-symb (intern 
                   (morph::concatstrings
                    (mapcar #'(lambda (s) (format nil "~S:" s)) set)))))
    (dolist (elt set list)
      (setf list (substitute new-symb
                             elt
                             list)))))

#|
(equiv '(1 2 3 4 5 6 5 4 3 2 1) '(1 2 5))
|#

(defun equival1 (set list1 &optional other-lists)
  (let ((new-symb (intern 
                   (morph::concatstrings
                    (mapcar #'(lambda (s) (format nil "~S:" s)) set))))
        (r (append (list list1) other-lists)))
    (if other-lists
      (dotimes (n (length r) r)
        (dolist (elt set)
          (setf (nth n r) (substitute new-symb
                                      elt
                                      (nth n r)))))
      (equiv list1 set))))

(om::defmethod! equival ((set list) (seq1 list) &rest other-lists)
  :initvals '(nil nil nil)
  :icon 128
  (equival1 set seq1 other-lists))

(om::defmethod! ldl-equival ((set list) (l-seq list))
  :initvals '(nil nil)
  :icon 128
  (equival1 set (car l-seq) (cdr l-seq)))

#|
(defvar a '(3- 1 5 3- 2 1 2 1 s 1 5 3- 2 1 s 3- 2 1 5 2 3- 5 3- 2 1 3- 2 1 5 2 1 2 1 s 1 5 3- 2 1 1 s 3- 2 1 5 1 5 5 3- 1 3- 2 1 5 3- 2 1 3- 2 1 1 5 3- 2 1 s 3- 2 1 3- 5 5 3- 2 1 2 1 soupirs 3- 2 1 3- 5 3 2 1 2 1 s 1 3 5 3- 2 1 s 3 2 1 3- 5 3 2 1 3n 2 1 5 5 3n 2 1 3 2 1 5 3- 2 1 soupirs))
(defvar b '(1 3 1 s 3 1 5 3 2 1 3 3 3 1 1 5 5 3 3 3 1 s 5 3 1 1 3 1 s 3 3 1 5 3 1 3 3 3 1 5 5 5 3 3 1 s 5 3 1 s 3 1 s 3 2 1 3 3 2 1 3 3 3 1 5 5 1 3 s soupirs 5 3 1 s 3- 1 s 3 1 5 3 1 3 3 3 1 5 3 3 3 s 5 3 1 1 3 1 s 3 3 1 7 1 s 3 1 3 1 7 1 3 3 s 3 3 s 3 1 7 1 3 1 3 1 7 1 7 s 3 1 3 5 3 3 1 3 5 5 3 s 5 4 1 1 4 1 s 4 1 4 4 1 4 4 5 4 1 4 5 6- 4 6- ?))

(equival '(3 3- 3n) a)
(equival '(3 3- 3n) a b)
(morph::ldl-distance (list a b) 1 1 0 "rel" "short")
(morph::ldl-distance (equival '(3 3- 3n) a b) 1 1 0 "rel" "short")
|#