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open Core.Core_stable
module Stable = struct
module V1 = struct
include String.V1
end
end
open Stable
open! Core
open! Import
type builder =
{ choices : int list
; depth : int
}
[@@deriving compare, bin_io]
let to_string { choices; depth } =
let buffer = Buffer.create 10 in
(match choices with
| [] -> ()
| choice :: choices ->
Buffer.add_string buffer (Int.to_string choice);
List.iter choices ~f:(fun choice ->
Buffer.add_char buffer '-';
Buffer.add_string buffer (Int.to_string choice)));
Buffer.add_char buffer '_';
Buffer.add_string buffer (Int.to_string depth);
Buffer.contents buffer
;;
let empty = { choices = []; depth = 0 }
let choice_point t n = { choices = t.choices @ [ n ]; depth = 0 }
let descend t = { t with depth = t.depth + 1 }
let%test_module _ =
(module struct
let test t =
let s = to_string t in
print_endline s
;;
let%expect_test _ =
test { choices = [ 1; 2; 2; 1; 0 ]; depth = 0 };
[%expect {| 1-2-2-1-0_0 |}]
;;
let%expect_test _ =
test { choices = []; depth = 1 };
[%expect {| _1 |}]
;;
let%expect_test _ =
test empty;
[%expect {| _0 |}]
;;
let%expect_test _ =
test { choices = [ 30 ]; depth = 1 };
[%expect {| 30_1 |}]
;;
end)
;;
let finalize builder = to_string builder
module T : sig
type t = V1.t
type comparator_witness = V1.comparator_witness
include Sexpable.S with type t := t
include Binable.S with type t := t
include
Comparable.S_binable
with type t := t
and type comparator_witness := comparator_witness
include Stringable.S with type t := t
end = struct
include String
end
include T