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 }
15let advance_byte t = { t with index = t.index + 1; column = t.column + 1 }
16let advance_line t = { index = t.index + 1; line = t.line + 1; column = 1 }
17let advance_char c t = if c = '\n' then advance_line t else advance_byte t
18
19let advance_utf8 uchar t =
20 let len = Uchar.utf_8_byte_length uchar in
21 let code = Uchar.to_int uchar in
22 if code = 0x0A (* LF *) then
23 { index = t.index + len; line = t.line + 1; column = 1 }
24 else { t with index = t.index + len; column = t.column + 1 }
25
26let advance_bytes n t = { t with index = t.index + n; column = t.column + n }
27let pp fmt t = Format.fprintf fmt "line %d, column %d" t.line t.column
28let to_string t = Format.asprintf "%a" pp t
29let compare a b = Int.compare a.index b.index
30let equal a b = a.index = b.index