+ Cluster(Cluster &&c)
+ : proto{}
+ {
+ *this = move(c);
+ };
+ Cluster &operator = (Cluster &&c) {
+ count = exchange(c.count, 0);
+ proto = exchange(c.proto, Server{});
+ cluster = exchange(c.cluster, {});
+ pids = exchange(c.pids, {});
+ return *this;
+ }