12 std::ostream&
operator<<(std::ostream& os,
const std::vector<MemoryID>& rhs);
bool compareTimestamp(const MemoryID &lhs, const MemoryID &rhs)
lhs.timestamp < rhs.timstamp
std::ostream & operator<<(std::ostream &os, const EntityUpdate &rhs)
bool compareTimestampDecreasing(const MemoryID &lhs, const MemoryID &rhs)
lhs.timestamp > rhs.timstamp