-extern XBT_PRIVATE std::set<std::string, std::less<>> created_categories;
-extern XBT_PRIVATE std::set<std::string, std::less<>> declared_marks;
-extern XBT_PRIVATE std::set<std::string, std::less<>> user_host_variables;
-extern XBT_PRIVATE std::set<std::string, std::less<>> user_vm_variables;
-extern XBT_PRIVATE std::set<std::string, std::less<>> user_link_variables;
-