; Was Desargues Right?
; This program relies on case sensitive symbols.
(let ((tf (lambda (field)
  (let* (
     (P ((fileVal "PGc") field 2))
     (p= (P 'e=))
     (me (P 'meet))
     (jo (P 'join))
     (pp (P 're))
     (a (pp 1))(b (pp 1))(c (pp 1))
     (A (pp 1))(B (pp 1))(Ci (pp 1))
     (ab (jo a b))(ac (jo a c))(bc (jo b c))
     (AB (jo A B))(AC (jo A Ci))
     (ml (jo (me ab AB) (me ac AC)))
     (mp (me (jo A a) (jo B b)))
     (Cc (jo mp c))
     (C (me AC Cc))
     (BC (jo B C))
     (val (= 1 (length (me ml (me bc BC))))))

 (write (list (= 0 (length (jo ml (me bc BC))))
         ; (list A B C a b c ab ac bc)
          (map length (list A B C a b c ab ac bc))
         (map length (list AB AC ml mp Cc C))))
  (newline)
  val))))
(list
  (tf (list ((fileVal "rr") "fit") 0 zero? 1 + - * /))
  (tf ((fileVal "GFpq") 7 5 "grrg"))
  )) ; => (#t #t)