Delayed list in various programming languages

From.scala

scala> def from(n: Int): LazyList[Int] = LazyList.cons(n, from(n + 1))
def from(n: Int): LazyList[Int]

scala> from(0).take(10).toList
val res0: List[Int] = List(0, 1, 2, 3, 4, 5, 6, 7, 8, 9)

module IList = struct
    type 'a lazy_list = LNil | LCons of 'a * (unit -> 'a lazy_list)

    let rec take n xs = match (n, xs) with
    | 0, xs -> []
    | n, LCons(x, xs) -> x::(take (n - 1) (xs()))
    | _, _ -> failwith "not defined"

    let rec from n = LCons(n, (fun () -> from (n + 1)))
end;;

open IList;;
let nat = from 0;;
print_string (String.concat " " (List.map string_of_int (take 10 nat)));;