Function R_altrep_class_name

r/src/arrow_cpp11.h:43–45

// R_altrep_class_name and R_altrep_class_package don't exist before R 4.6
#if R_VERSION < R_Version(4, 6, 0)
inline SEXP R_altrep_class_name(SEXP x) {
  return ALTREP(x) ? CAR(ATTRIB(ALTREP_CLASS(x))) : R_NilValue;
}
inline SEXP R_altrep_class_package(SEXP x) {
  return ALTREP(x) ? CADR(ATTRIB(ALTREP_CLASS(x))) : R_NilValue;
}