- for (size_t i = 0; i < grid_names.size(); i++) {
- if (!grid_names[i].empty()) {
- os << (is_first ? "" : "\n") << grid_names[i];
+ for (const std::string &grid_name : grid_names) {
+ if (!grid_name.empty()) {
+ os << (is_first ? "" : "\n") << grid_name;