- auto i = std::find_if(std::cbegin(this->mapping),
- std::cend(this->mapping),
- [layer_id](struct layer const &l) {
- return layer_id == l.layer_id;
- });
- return i == this->mapping.end() ? nullopt : optional<struct layer>(*i);
+ auto i = this->mapping.find(layer_id);
+ return i == this->mapping.end() ? nullopt
+ : optional<struct layer>(i->second);