- for (auto card : vertices_) {
- s4u::Host* host = simgrid::s4u::Host::by_name_or_null(card->name());
- if (host != nullptr)
- hosts_->push_back(host);
- }
- return hosts_;
+ if (hosts_.empty()) // Lazy initialization
+ for (auto card : vertices_) {
+ s4u::Host* host = simgrid::s4u::Host::by_name_or_null(card->name());
+ if (host != nullptr)
+ hosts_.push_back(host);
+ }
+ return &hosts_;