Print list

debug.sml

(* List print for debug *)
fun print_list nil      = print "nil\n"
  | print_list (x::xs)  =
    let
      fun print_list_ nil      = "nil"
        | print_list_ (x::nil) = String.concat([(Int.toString(x)), "\n"])
        | print_list_ (x::xs)  = String.concat([Int.toString x, ", ", print_list_ xs])
    in
      print (print_list_ (x::xs))
    end;

print_list nil;
(*
nil
val it = () : unit
*)

print_list [1, 2, 3, 4, 5];
(*
1, 2, 3, 4, 5
val it = () : unit
*)