Pure OCaml Yaml 1.2 reader and writer using Bytesrw
anil.recoil.org
1(*---------------------------------------------------------------------------
2 Copyright (c) 2025 Anil Madhavapeddy <anil@recoil.org>. All rights reserved.
3 SPDX-License-Identifier: ISC
4 ---------------------------------------------------------------------------*)
5
6(** Position tracking for source locations *)
7
8type t = {
9 index : int; (** Byte offset from start *)
10 line : int; (** 1-indexed line number *)
11 column : int; (** 1-indexed column number *)
12}
13
14let initial = { index = 0; line = 1; column = 1 }
15
16let advance_byte t =
17 { t with index = t.index + 1; column = t.column + 1 }
18
19let advance_line t =
20 { index = t.index + 1; line = t.line + 1; column = 1 }
21
22let advance_char c t =
23 if c = '\n' then advance_line t
24 else advance_byte t
25
26let advance_utf8 uchar t =
27 let len = Uchar.utf_8_byte_length uchar in
28 let code = Uchar.to_int uchar in
29 if code = 0x0A (* LF *) then
30 { index = t.index + len; line = t.line + 1; column = 1 }
31 else
32 { t with index = t.index + len; column = t.column + 1 }
33
34let advance_bytes n t =
35 { t with index = t.index + n; column = t.column + n }
36
37let pp fmt t =
38 Format.fprintf fmt "line %d, column %d" t.line t.column
39
40let to_string t =
41 Format.asprintf "%a" pp t
42
43let compare a b =
44 Int.compare a.index b.index
45
46let equal a b =
47 a.index = b.index