36     upper_.emplace(std::move(*u));
53   if (upper_) {  in upper()
54     return {upper_.value().value()};  in upper()
60   upper_.emplace(std::move(expr));  in set_upper()
144   if (upper_) {  in upper()
145     return upper_.value().value();  in upper()
160   upper_.emplace(std::move(expr));  in set_upper()
176   if (!upper_) {  in Fold()
177     upper_ = upper();  in Fold()
178     if (!upper_) {  in Fold()
182   upper_.value() = evaluate::Fold(context, std::move(upper_.value().value()));  in Fold()
183   if (std::optional<ConstantSubscript> ubi{ToInt64(upper_.value().value())}) {  in Fold()
199       upper_ = AsExpr(Constant<SubscriptInteger>{*ubi});  in Fold()
222       upper_ = AsExpr(Constant<SubscriptInteger>{length});  in Fold()
644   return lower_ == that.lower_ && upper_ == that.upper_ &&  in operator ==()
661       upper_ == that.upper_;  in operator ==()