let dt = 0.001
let g  = 9.81

let node f_integr (x0, x') = x where
  rec x = x0 -> pre (x +. x' *. dt)
let node b_integr (x0, x') = x where
  rec x = x0 -> (pre x) +. x' *. dt

let node bouncing_ball (p0, v0) = p where
  rec p = reset f_integr (q, v)    every z
  and v = reset b_integr (w, -. g) every z
  and q = p0 -> 0.0 and w = v0 -> -0.8 *. (pre v)
  and z = false fby (p < 0.0)

let node main () =
  let rec t = 0.0 fby (dt +. t) in
  let p = bouncing_ball (5.0, 0.0) in
  match t <= 10.0 with
  | true -> (print_float t; print_string "\t"; print_float p; print_newline ())
  | false -> ()