factorial.ml

#use "topfind"
#thread
#require "core"
open Core


let rec factorial (number : int) =
  if number >= 1 then number * factorial (number - 1)
  else 1 ;;

let test (f : int -> int) = 
    f ;;

let print_fac (number : int)  = sprintf "%i! = %i\n" number (factorial number);;

let read_number = int_of_string Sys.argv.(0);;

printf "%s" (read_number |> print_fac) 


(* 
  Exception: Failure "int_of_string".
  Raised by primitive operation at file "./test.ml", line 19, characters 18-44
  Called from file "toplevel/toploop.ml", line 180, characters 17-56
*)