From ca289b2f43a5b097c4ec20308c1661a0c404399c Mon Sep 17 00:00:00 2001 From: Lukasz Kasprzak Date: Tue, 11 Aug 2026 11:25:56 +0200 Subject: kernel: Slug and Lang validated private strings Both parse through a smart constructor returning result, and both hand-write t_of_sexp so a malformed value in a data file is rejected at load rather than silently accepted -- deriving the converter would have bypassed validation. --- lib/kernel/lang.ml | 23 +++++++++++++++++++++++ 1 file changed, 23 insertions(+) create mode 100644 lib/kernel/lang.ml (limited to 'lib/kernel/lang.ml') diff --git a/lib/kernel/lang.ml b/lib/kernel/lang.ml new file mode 100644 index 0000000..3f45f59 --- /dev/null +++ b/lib/kernel/lang.ml @@ -0,0 +1,23 @@ +(* Language codes for celebration names. Two-letter lowercase ISO-639-1; the set + is open so an overlay can add a language without a code change (spec ยง2.1). *) +type t = string + +let of_string s = + if String.length s <> 2 then + Error (Printf.sprintf "lang %S: expected a 2-letter ISO-639-1 code" s) + else if not (String.for_all (fun c -> c >= 'a' && c <= 'z') s) then + Error (Printf.sprintf "lang %S: must be lowercase a-z" s) + else Ok s + +let of_string_exn s = match of_string s with Ok t -> t | Error e -> invalid_arg e +let to_string t = t +let compare = String.compare +let equal = String.equal + +let sexp_of_t t = Sexplib0.Sexp_conv.sexp_of_string t + +let t_of_sexp sexp = + let s = Sexplib0.Sexp_conv.string_of_sexp sexp in + match of_string s with + | Ok t -> t + | Error msg -> Sexplib0.Sexp_conv.of_sexp_error msg sexp -- cgit v1.3