
use int.Int

val ref x : int

let set_x (n:int) : unit
  ensures { x > n }
  =
  x <- n + 1

let main () : unit
  =
  x <- 0;
  set_x 2;
  assert { x = 3 }


let incr (x:int) : int
  ensures { result > x }
  = x+1

let test () =
  let y = incr 1 in
  assert { y = 2 }
