Method r_string_from_view

r/src/array_to_vector.cpp:376–378

 private:
  static SEXP r_string_from_view(std::string_view view) {
    return Rf_mkCharLenCE(view.data(), static_cast<int>(view.size()), CE_UTF8);
  }

  static SEXP r_string_from_view_strip_nul(std::string_view view,
                                           bool* nul_was_stripped) {