SCM_API SCM scm_slot_ref_using_class (SCM cls, SCM obj, SCM slot_name);
SCM_API SCM scm_slot_set_using_class_x (SCM cls, SCM obj, SCM slot_name, SCM value);
SCM_API SCM scm_slot_bound_using_class_p (SCM cls, SCM obj, SCM slot_name);
SCM_API SCM scm_slot_ref_using_class (SCM cls, SCM obj, SCM slot_name);
SCM_API SCM scm_slot_set_using_class_x (SCM cls, SCM obj, SCM slot_name, SCM value);
SCM_API SCM scm_slot_bound_using_class_p (SCM cls, SCM obj, SCM slot_name);