An implementation of Riak's ORSWOT CRDT which is a CRDT which allows for removal of old tombstones once a new event has been observed.
The set is built upon the second supported structure HLCTimestamp which is a Hybrid Logical Clock
which guarantees the timestamp will always be unique and monotonic (providing it's used correctly.)
```rust use datacakecrdt::{OrSWotSet, HLCTimestamp, getunixtimestampms};
fn main() { let mut nodea = HLCTimestamp::new(getunixtimestampms(), 0, 0);
// Simulating a node begin slightly ahead.
let mut node_b = HLCTimestamp::new(get_unix_timestamp_ms() + 5000, 0, 1);
let mut node_a_set = OrSWotSet::default();
let mut node_b_set = OrSWotSet::default();
// Insert a new key with a new timestamp in set A.
node_a_set.insert(1, node_a.send().unwrap());
// Insert a new entry in set B.
node_b_set.insert(2, node_b.send().unwrap());
// Let some time pass for demonstration purposes.
std::thread::sleep(std::time::Duration::from_millis(500));
// Set A has key `1` removed.
node_a_set.delete(1, node_a.send().unwrap());
// Merging set B with set A and vice versa.
// Our sets are now aligned without conflicts.
node_b_set.merge(node_a_set.clone());
node_a_set.merge(node_b_set);
// Set A and B should both see that key `1` has been deleted.
assert!(node_a_set.get(&1).is_none(), "Key a was not correctly removed.");
assert!(node_b_set.get(&1).is_none(), "Key a was not correctly removed.");
} ```