(test-group "absento tests"
  ; Tests commented out are for general absento; this implementation only supports
  ; absento where the first argument is a ground atom.

  ;(test "test 0"
  ;(run* (q) (absento q q))
  ;'())

  ;(test "test 1"
  ;(run* (q)
  ;(fresh (a b c)
  ;(== a b)
  ;(absento b c)
  ;(== c b)
  ;(== `(,a ,b ,c) q)))
  ;'())

  ;(test "test 2"
  ;(run* (q)
  ;(fresh (a)
  ;(absento q a)
  ;(absento `((,q ,q) 3 (,q ,q)) `(,a 3 ,a))))
  ;'(_.0))

  ;(test "test 3"
  ;(run* (q)
  ;(fresh (a b)
  ;(absento q a)
  ;(absento `(3 ,a) `(,b ,a))
  ;(== 3 b)))
  ;'())

  ;(test "test 4"
  ;(run* (q)
  ;(fresh (a b)
  ;(absento q a)
  ;(absento `(3 ,a) `(,q ,a))
  ;(== 3 b)))
  ;'((_.0 (=/= ((_.0 3))))))

  ;(test "test 5"
  ;(run* (q)
  ;(fresh (a b)
  ;(numbero a)
  ;(numbero b)
  ;(absento '(3 3) `(,a ,b))
  ;(=/= a b)
  ;(== `(,a ,b) q)))
  ;'(((_.0 _.1) (=/= ((_.0 _.1))) (num _.0 _.1))))

  ;(test "test 6"
  ;(run* (q) (fresh (a) (absento q a) (== q a)))
  ;'())

  ;(test "test 7"
  ;(run* (q)
  ;(fresh (a b c)
  ;(absento '(3 . 4) c)
  ;(== `(,a . ,b) c)
  ;(== q `(,a . ,b))))
  ;'(((_.0 . _.1) (=/= ((_.0 3) (_.1 4))) (absento ((3 . 4) _.0) ((3 . 4) _.1)))))

  ;; (test "test 8"
  ;;   (run* (q)
  ;;     (fresh (a b)
  ;;       (absento 5 a)
  ;;       (symbolo b)
  ;;       (== `(,q ,b) a)))
  ;;   '((_.0 (absento (5 _.0)))))

  ;; (test "test 9"
  ;;   (run* (q)
  ;;     (fresh (a b)
  ;;       (absento 5 a)
  ;;       (== `(,q ,b) a)))
  ;;   '((_.0 (absento (5 _.0)))))

  ;(test "test 10"
  ;(run* (q) (fresh (a) (absento `(3 . ,a) q) (absento q `(3 . ,a))))
  ;'((_.0 (=/= ((_.0 3))))))

  ;(test "test 11"
  ;(run* (q)
  ;(fresh (a b c d e f)
  ;(absento `(,a . ,b) q)
  ;(absento q `(,a . ,b))
  ;(== `(,c . ,d) a)
  ;(== `(3 . ,e) c)
  ;(== `(,f . 4) d)))
  ;'((_.0 (=/= ((_.0 3)) ((_.0 4))))))

  ;(test "test 12"
  ;(run* (q)
  ;(fresh (a b c)
  ;(absento `(,3 . ,a) `(,b . ,c))
  ;(numbero b)
  ;(== `(,a ,b ,c) q)))
  ;'(((_.0 _.1 _.2) (=/= ((_.0 _.2) (_.1 3))) (num _.1) (absento ((3 . _.0) _.2)))))

  ;(test "test 13"
  ;(run* (q)
  ;(fresh (a b c)
  ;(== `(,a . ,b) q)
  ;(absento '(3 . 4) q)
  ;(numbero a)
  ;(numbero b)))
  ;'(((_.0 . _.1) (=/= ((_.0 3) (_.1 4))) (num _.0 _.1))))

  ;(test "test 14"
  ;(run* (q)
  ;(fresh (a b)
  ;(absento '(3 . 4) `(,a . ,b))
  ;(== `(,a . ,b) q)))
  ;'(((_.0 . _.1) (=/= ((_.0 3) (_.1 4))) (absento ((3 . 4) _.0) ((3 . 4) _.1)))))

  ;(test "test 15"
  ;(run* (q)
  ;(absento q `(3 . (4 . 5))))
  ;'((_.0 (=/= ((_.0 3))
  ;((_.0 4))
  ;((_.0 5))
  ;((_.0 (3 . (4 . 5))))
  ;((_.0 (4 . 5)))))))

  ;(test "test 16"
  ;(run* (q)
  ;(fresh (a b x)
  ;(absento a b)
  ;(symbolo a)
  ;(numbero x)
  ;(== x b)
  ;(== `(,a ,b) q)))
  ;'(((_.0 _.1) (num _.1) (sym _.0))))

  ;; (test "test 19"
  ;;   (run* (q) (absento 5 q) (absento 5 q))
  ;;   '((_.0 (absento (5 _.0)))))

  ;; (test "test 20"
  ;;   (run* (q) (absento 5 q) (absento 6 q))
  ;;   '((_.0 (absento (5 _.0) (6 _.0)))))

  ;; (test "test 21"
  ;;   (run* (q) (absento 5 q) (symbolo q))
  ;;   '((_.0 (sym _.0))))

  (test "test 22"
        (run* (q) (numbero q) (absento 'tag q))
        '((_.0 (num _.0))))

  (test "test 23"
        (run* (q) (absento 'tag q) (numbero q))
        '((_.0 (num _.0))))

  (test "test 24"
        (run* (q) (== 5 q) (absento 5 q))
        '())

  (test "test 25"
        (run* (q) (== q `(5 6)) (absento 5 q))
        '())

  (test "test 25b"
        (run* (q) (absento 5 q) (== q `(5 6)))
        '())

  (test "test 26"
        (run* (q) (absento 5 q) (== 5 q))
        '())

  ;; (test "test 27"
  ;;   (run* (q) (absento 'tag1 q) (absento 'tag2 q))
  ;;   '((_.0 (absento (tag1 _.0) (tag2 _.0)))))

  (test "test 28"
        (run* (q) (absento 'tag q) (numbero q))
        '((_.0 (num _.0))))

  ;(test "test 29"
  ;(run* (q)
  ;(fresh (a b)
  ;(absento a b)
  ;(absento b a)
  ;(== `(,a ,b) q)
  ;(symbolo a)
  ;(numbero b)))
  ;'(((_.0 _.1) (num _.1) (sym _.0))))

  ;(test "test 30"
  ;(run* (q)
  ;(fresh (a b)
  ;(absento b a)
  ;(absento a b)
  ;(== `(,a ,b) q)
  ;(symbolo a)
  ;(symbolo b)))
  ;'(((_.0 _.1) (=/= ((_.0 _.1))) (sym _.0 _.1))))

  ;(test "test 31"
  ;(run* (q)
  ;(fresh (a b)
  ;(absento a b)
  ;(absento b a)
  ;(== `(,a ,b) q)))
  ;'(((_.0 _.1) (absento (_.0 _.1) (_.1 _.0)))))

  ;; (test "test 32"
  ;;   (run* (q)
  ;;     (fresh (a b)
  ;;       (absento 5 a)
  ;;       (absento 5 b)
  ;;       (== `(,a . ,b) q)))
  ;;   '(((_.0 . _.1) (absento (5 _.0) (5 _.1)))))

  (test "test 33"
        (run* (q)
          (fresh (a b c)
            (== `(,a ,b) c)
            (== `(,c ,c) q)
            (symbolo b)
            (numbero c)))
        '())

  (test "test 34"
        (run* (q) (absento 'tag q) (symbolo q))
        '((_.0 (=/= ((_.0 tag))) (sym _.0))))

  ;; (test "test 35"
  ;;   (run* (q) (absento 5 q) (numbero q))
  ;;   '((_.0 (=/= ((_.0 5))) (num _.0))))

  ;(test "test 36"
  ;(run* (q)
  ;(fresh (a)
  ;(== 5 a) (absento a q)))
  ;'((_.0 (absento (5 _.0)))))

  ;(test "test 37"
  ;(run* (q)
  ;(fresh (a b)
  ;(absento a b)
  ;(absento b a)
  ;(== `(,a ,b) q)
  ;(symbolo a)
  ;(symbolo b)))
  ;'(((_.0 _.1) (=/= ((_.0 _.1))) (sym _.0 _.1))))

  ;; (test "test 38"
  ;;   (run* (q) (absento '() q))
  ;;   '((_.0 (absento (() _.0)))))

  ;(test "test 39"
  ;(run* (q) (absento `(3 4) q))
  ;'((_.0 (absento ((3 4) _.0)))))

  (test "test 40"
        (run* (q)
          (fresh (d a c)
            (== `(3 . ,d) q)
            (=/= `(,c . ,a) q)
            (== '(3 . 4) d)))
        '((3 3 . 4)))

  (test "test 41"
        (run* (q)
          (fresh (a)
            (== `(,a . ,a) q)))
        '((_.0 . _.0)))

  ;(test "test 42"
  ;(run* (q)
  ;(fresh (a b)
  ;(==  `((3 4) (5 6)) q)
  ;(absento `(3 4) q)))
  ;'())

  ;(test "test 43"
  ;(run* (q) (absento q 3))
  ;'((_.0 (=/= ((_.0 3))))))

  ;(test "test 44"
  ;(run* (q)
  ;(fresh (a b)
  ;(absento a b)
  ;(absento b a)
  ;(== `(,a ,b) q)))
  ;'(((_.0 _.1) (absento (_.0 _.1) (_.1 _.0)))))

  ;(test "test 45"
  ;(run* (q)
  ;(fresh (a b)
  ;(absento `(,a . ,b) q)
  ;(== q `(3 . (,b . ,b)))))
  ;'((3 _.0 . _.0)))

  ;(test "test 45b"
  ;(run* (q)
  ;(fresh (a b)
  ;(absento `(,a . ,b) q)
  ;(== q `(,a 3 . (,b . ,b)))))
  ;'(((_.0 3 _.1 . _.1) (=/= ((_.0 _.1))))))

  ;(test "test 46"
  ;(run* (q)
  ;(fresh (a)
  ;(absento a q)
  ;(absento q a)))
  ;'(_.0))

  ;(test "test 47"
  ;(run* (q)
  ;(fresh (a)
  ;(absento `(,a . 3) q)))
  ;'(_.0))

  ;(test "test 48"
  ;(run* (q)
  ;(fresh (a)
  ;(absento `(,a . 3) q)))
  ;'(_.0))

  ;(test "test 49"
  ;(run* (q)
  ;(fresh (a b c d e)
  ;(absento `((3 4 ,a) (4 ,b) ((,c)) ,d ,e) q)))
  ;'(_.0))

  ;(test "test 50"
  ;(run* (q)
  ;(fresh (a)
  ;(absento a q)
  ;(== 5 a)))
  ;'((_.0 (absento (5 _.0)))))

  ;(test "test 51"
  ;(run* (q)
  ;(fresh (a b c d)
  ;(== a 5)
  ;(== a b)
  ;(== b c)
  ;(absento d q)
  ;(== c d)))
  ;'((_.0 (absento (5 _.0)))))

  ;(test "test 52"
  ;(run* (q)
  ;(fresh (a b c d)
  ;(== a b)
  ;(== b c)
  ;(absento a q)
  ;(== c d)
  ;(== d 5)))
  ;'((_.0 (absento (5 _.0)))))

  ;(test "test 53"
  ;(run* (q)
  ;(fresh (t1 t2 a)
  ;(== `(,a . 3) t1)
  ;(== `(,a . (4 . 3)) t2)
  ;(== `(,t1 ,t2) q)
  ;(absento t1 t2)))
  ;'((((_.0 . 3) (_.0 4 . 3)) (=/= ((_.0 4))))))

  ;(test "test 54"
  ;(run* (q)
  ;(fresh (a)
  ;(== `(,a . 3) q)
  ;(absento q `(,a . (4 . 3)))))
  ;'(((_.0 . 3) (=/= ((_.0 4))))))

  ;(test "test 55"
  ;(run* (q)
  ;(fresh (a d c)
  ;(== '(3 . 4) d)
  ;(absento `(3 . 4) q)
  ;(== `(3 . ,d) q)))
  ;'())

  ;(test "test 56"
  ;(run* (q)
  ;(fresh (a b)
  ;(absento a b)
  ;(absento b a)
  ;(== `(,a ,b) q)
  ;(symbolo a)
  ;(numbero b)))
  ;'(((_.0 _.1) (num _.1) (sym _.0))))


  ;(test "test 57"
  ;(run* (q)
  ;(numbero q)
  ;(absento q 3))
  ;'((_.0 (=/= ((_.0 3))) (num _.0))))

  ;(test "test 58"
  ;(run* (q)
  ;(fresh (a)
  ;(== `(,a . 3) q)
  ;(absento q `(,a . (4 . (,a . 3))))))
  ;'())

  ;(test "test 59"
  ;(run* (q)
  ;(fresh (a)
  ;(== `(,a . 3) q)
  ;(absento q `(,a . ((,a . 3) . (,a . 4))))))
  ;'())

  ;(test "test 60"
  ;(run* (q)
  ;(fresh (a d c)
  ;(== `(3 . ,d) q)
  ;(== '(3 . 4) d)
  ;(absento `(3 . 4) q)))
  ;'())

  ;(test "test 61"
  ;(run* (q)
  ;(fresh (a b c)
  ;(symbolo b)
  ;(absento `(,3 . ,a) `(,b . ,c))
  ;(== `(,a ,b ,c) q)))
  ;'(((_.0 _.1 _.2) (sym _.1) (absento ((3 . _.0) _.2)))))

  ;(test "test 62"
  ;(run* (q) (fresh (a b c) (absento a b) (absento b c) (absento c q) (symbolo a)))
  ;'(_.0))

  (test "test 63"
        (run* (q) (fresh (a b c) (=/= a b) (=/= b c) (=/= c q) (symbolo a)))
        '(_.0))

  (test "test 64"
        (run* (q) (symbolo q) (== 'tag q))
        '(tag))

  ;(test "test 65"
  ;(run* (q) (fresh (b) (absento '(3 4) `(,q ,b))))
  ;'((_.0 (absento ((3 4) _.0)))))

  ;; (test "test 66"
  ;;   (run* (q) (absento 6 5))
  ;;   '(_.0))

  ;; (test "test 67"
  ;;   (run* (q)
  ;;     (fresh (a b)
  ;;       (=/= a b)
  ;;       (symbolo a)
  ;;       (numbero b)
  ;;       (== `(,a ,b) q)))
  ;;   '(((_.0 _.1) (num _.1) (sym _.0))))

  ;; (test "test 68"
  ;;   (run* (q)
  ;;     (fresh (a b c d)
  ;;       (=/= `(,a ,b) `(,c ,d))
  ;;       (symbolo a)
  ;;       (numbero c)
  ;;       (symbolo b)
  ;;       (numbero c)
  ;;       (== `(,a ,b ,c ,d) q)))
  ;;   '(((_.0 _.1 _.2 _.3) (num _.2) (sym _.0 _.1))))

  ;; (test "test 69"
  ;;   (run* (q)
  ;;     (fresh (a b)
  ;;       (=/= `(,a . 3) `(,b . 3))
  ;;       (symbolo a)
  ;;       (numbero b)
  ;;       (== `(,a ,b) q)))
  ;;    '(((_.0 _.1) (num _.1) (sym _.0))))

  ;(test "test 70"
  ;(run* (q)
  ;(fresh (a b)
  ;(absento a b)
  ;(absento b a)
  ;(== `(,a ,b) q)
  ;(symbolo a)
  ;(numbero b)))
  ;'(((_.0 _.1) (num _.1) (sym _.0))))

  ;(test "test 70b"
  ;(run* (q)
  ;(fresh (a b)
  ;(symbolo a)
  ;(numbero b)
  ;(absento a b)
  ;(absento b a)
  ;(== `(,a ,b) q)))
  ;'(((_.0 _.1) (num _.1) (sym _.0))))

  ;(test "test 71"
  ;(run* (q)
  ;(fresh (a b)
  ;(absento a b)
  ;(absento b a)
  ;(== `(,a ,b) q)
  ;(symbolo a)
  ;(symbolo b)))
  ;'(((_.0 _.1) (=/= ((_.0 _.1))) (sym _.0 _.1))))

  ;(test "test 72"
  ;(run* (q)
  ;(fresh (a b)
  ;(absento a b)
  ;(absento b a)
  ;(== `(,a ,b) q)))
  ;'(((_.0 _.1) (absento (_.0 _.1) (_.1 _.0)))))

  ;(test "test 73"
  ;(run* (q)
  ;(fresh (a b)
  ;(== `(,a ,b) q)
  ;(absento b a)
  ;(absento a b)
  ;(== a '(1 . 2))))
  ;'((((1 . 2) _.0)
  ;(=/= ((_.0 1)) ((_.0 2)))
  ;(absento ((1 . 2) _.0)))))

  ;(test "test 74"
  ;(run* (q)
  ;(fresh (a b c)
  ;(absento a q)
  ;(absento q a)
  ;(== `(,b . ,c) a)
  ;(== '(1 . 2) b)
  ;(== '(3 . 4) c)))
  ;'((_.0 (=/= ((_.0 1)) ((_.0 2)) ((_.0 3)) ((_.0 4))
  ;((_.0 (1 . 2))) ((_.0 (3 . 4))))
  ;(absento (((1 . 2) 3 . 4) _.0)))))

  ;(test "test 75"
  ;(run* (q)
  ;(fresh (a b c d e f g)
  ;(absento a q)
  ;(absento q a)
  ;(== `(,b . ,c) a)
  ;(== `(,d . ,e) b)
  ;(== `(,f . ,g) c)
  ;(== '(1 . 2) d)
  ;(== '(3 . 4) e)
  ;(== '(5 . 6) f)
  ;(== '(7 . 8) g)))
  ;'((_.0 (=/= ((_.0 ((1 . 2) 3 . 4)))
  ;((_.0 ((5 . 6) 7 . 8)))
  ;((_.0 1))
  ;((_.0 2))
  ;((_.0 3))
  ;((_.0 4))
  ;((_.0 5))
  ;((_.0 6))
  ;((_.0 7))
  ;((_.0 8))
  ;((_.0 (1 . 2)))
  ;((_.0 (3 . 4)))
  ;((_.0 (5 . 6)))
  ;((_.0 (7 . 8))))
  ;(absento ((((1 . 2) 3 . 4) (5 . 6) 7 . 8) _.0)))))

  ;(test "test 76"
  ;(run* (q)
  ;(absento 3 q)
  ;(absento '(3 4) q))
  ;'((_.0 (absento (3 _.0)))))

  ;(test "test 77"
  ;(run* (q)
  ;(fresh (x a b)
  ;(== x `(,a ,b))
  ;(absento '(3 4) x)
  ;(absento 3 a)
  ;(absento 4 b)
  ;(== q `(,a 2))))
  ;'(((_.0 2) (absento (3 _.0)))))

  ;(test "test 78"
  ;(run* (q)
  ;(fresh (d)
  ;(== `(3 . ,d) q)
  ;(absento `(3 . 4) q)
  ;(== '(3 . 4) d)))
  ;'())

  ;(test "test 79"
  ;(run* (q)
  ;(fresh (d)
  ;(absento `(3 . 4) q)
  ;(== `(3 . ,d) q)
  ;(== '(3 . 4) d)))
  ;'())

  ;(test "test 80"
  ;(run* (q)
  ;(fresh (d a c)
  ;(== `(3 . ,d) q)
  ;(absento `(3 . ,a) q)
  ;(== c d)
  ;(== `(3 . ,a) c)))
  ;'())

  ;(test "test 81"
  ;(run* (q)
  ;(fresh (a b)
  ;(absento `(3 . ,a) `(,b . 4))
  ;(== `(,a . ,b) q)))
  ;'(((_.0 . _.1) (=/= ((_.0 4) (_.1 3))) (absento ((3 . _.0) _.1)))))

  ;(test "test 82"
  ;(run* (q)
  ;(fresh (d)
  ;(== `(3 . ,d) q)
  ;(absento `(3 . 4) q)))
  ;'(((3 . _.0) (=/= ((_.0 4))) (absento ((3 . 4) _.0)))))

  ;(test "test 83"
  ;(run* (q)
  ;(fresh (d)
  ;(== `(3 . ,d) q)
  ;(== '(3 . 4) d))
  ;(absento `(3 . 4) q))
  ;'())

  ;(test "test 84"
  ;(run* (q)
  ;(fresh (a b c d)
  ;(=/= `(,a . ,b) `(,c . ,d))
  ;(absento a c)
  ;(== `(,a ,b ,c ,d) q)))
  ;'(((_.0 _.1 _.2 _.3) (absento (_.0 _.2)))))

  ;(test "test 84 b"
  ;(run* (q)
  ;(fresh (a b c d)
  ;(=/= `(,a . ,b) `(,c . ,d))
  ;(absento c a)
  ;(== `(,a ,b ,c ,d) q)))
  ;'(((_.0 _.1 _.2 _.3) (absento (_.2 _.0)))))

  ;(test "test 85 a"
  ;(run* (q)
  ;(fresh (a b)
  ;(=/= a b)
  ;(absento a b)
  ;(== `(,a ,b) q)))
  ;'(((_.0 _.1) (absento (_.0 _.1)))))

  ;(test "test 85 b"
  ;(run* (q)
  ;(fresh (a b)
  ;(absento a b)
  ;(=/= a b)
  ;(== `(,a ,b) q)))
  ;'(((_.0 _.1) (absento (_.0 _.1)))))
  )