public string TryParse(string source, ref int index, ref JsonPath path)
        {
            if (path == null)
            {
                return("Start token not found.");
            }

            index += 2;
            var error = source.GetSlices(ref index, out var slices);

            if (error != null)
            {
                return(error);
            }

            path = path.SearchArray(slices.ToArray());
            return(null);
        }