Function constexpr

src/ifcparse/IfcParse.cpp:2380–2393

        }
#ifdef IFOPSH_WITH_ROCKSDB
        else if constexpr (std::is_same_v<std::decay_t<decltype(x)>, impl::rocks_db_file_storage>) {
            // @todo no lower/upper_bounds() implemented yet
            auto prefix = "v|" + std::to_string(t) + "|";
            auto it = std::unique_ptr<rocksdb::Iterator>(x.db->NewIterator(rocksdb::ReadOptions()));
            it->Seek(prefix);
            while (it->Valid() && it->key().starts_with(prefix)) {
                std::vector<uint32_t> vals(it->value().size() / sizeof(uint32_t));
                memcpy(vals.data(), it->value().data(), it->value().size());
                for (auto& v : vals) {
                    ret->push(instance_by_id(v));
                }
                it->Next();
            }
        }
#endif
        else {
            throw std::runtime_error("Storage not initialized");