Source file validated_string.ml

(*******************************************************************************)
(*  Vcs - a Versatile OCaml Library for Git Operations                         *)
(*  Copyright (C) 2024 Mathieu Barbin <mathieu.barbin@gmail.com>               *)
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(*******************************************************************************)

module type S = Validated_string_intf.S
module type X = Validated_string_intf.X

module String = StringLabels

module Make (X : X) = struct
  let to_string t = t

  let of_string s =
    if X.invariant s
    then Ok s
    else (
      let shown_s =
        if String.length s > 40
        then
          String.sub s ~pos:0 ~len:40
          ^ "..."
          ^ Printf.sprintf " (%d characters total)" (String.length s)
        else s
      in
      Error (`Msg (Printf.sprintf "%S: invalid %s" shown_s X.module_name)))
  ;;

  let v s =
    match of_string s with
    | Ok t -> t
    | Error (`Msg m) -> raise (Invalid_argument m)
  ;;
end