(relation path (i64 i64))
(relation edge (i64 i64))

(rule ((edge x y))
      ((path x y)))

(rule ((path x y) (edge y z))
      ((path x z)))
        
(edge 1 2)
(edge 2 3)
(edge 3 4)
(check (edge 1 2))
(fail (check (path 1 2)))
(run 3)

(print-function path 100)
(check (path 1 4))
(fail (check (path 4 1)))