Source file `json_helpers.ml`

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let from_string s = Yojson.Safe.from_string s
let to_string (v : Yojson.Safe.t) = Yojson.Safe.to_string v
let member_or_null s (v : Yojson.Safe.t) = Yojson.Safe.Util.member s v

let field_map (x : Yojson.Safe.t) field_name f =
  match x with
  | `Assoc fields -> (
    match List.assoc_opt field_name fields with
    | None | Some `Null -> None
    | Some value -> Some (f value))
  | _ -> raise (Yojson.Safe.Util.Type_error ("Expected Assoc", x))
;;

let field_map_exn (x : Yojson.Safe.t) field_name f =
  match x with
  | `Assoc fields -> (
    match List.assoc_opt field_name fields with
    | Some value -> f value
    | None ->
      raise
        (Yojson.Safe.Util.Type_error (Printf.sprintf "Expected field '%s'" field_name, x))
    )
  | _ -> raise (Yojson.Safe.Util.Type_error ("Expected Assoc", x))
;;