code: func appliesTo(user user.Info, bindingSubjects []rbacv1.Subject, namespace string) (int, bool) {
  	for i, bindingSubject := range bindingSubjects {
  		if appliesToUser(user, bindingSubject, namespace) {
  			return i, true
  		}
  	}
  	return 0, false
  }
docs: // appliesTo returns whether any of the bindingSubjects applies to the specified subject,
  // and if true, the index of the first subject that applies