(define t (set (lambda (i j) (if (< i j) -1 (if (> i j) 1 0))))) ; if you want to sort integers

(define empty (car t)) (define empty? (cadr t))(define mem (caddr t))(define t (cdddr t))
(define add (car t)) (define singleton (cadr t))(define remove (caddr t))(define t (cdddr t))
(define union (car t)) (define inter (cadr t))(define diff (caddr t))(define t (cdddr t))
(define compare (car t)) (define equal (cadr t))(define subset (caddr t))(define t (cdddr t))
(define iter (car t)) (define fold (cadr t))(define for_all (caddr t))(define t (cdddr t))
(define exists (car t)) (define filter (cadr t))(define partition (caddr t))(define t (cdddr t))
(define cardinal (car t)) (define elements (cadr t))(define min_elt (caddr t))(define t (cdddr t))
(define max_elt (car t)) (define choose (cadr t))(define split (caddr t))