Struct LWWRegister 

pub struct LWWRegister<T: Clone> { /* private fields */ }

A last-writer-wins register (LWW-Register).

Resolves concurrent writes by keeping the value with the highest HybridTimestamp. This provides causally consistent ordering even with clock drift between nodes.

Example

use crdt_kit::prelude::*;
use crdt_kit::clock::HybridClock;

let mut clock1 = HybridClock::new(1);
let mut clock2 = HybridClock::new(2);

let mut r1 = LWWRegister::new("hello", &mut clock1);
let mut r2 = LWWRegister::new("world", &mut clock2);

r1.merge(&r2);
// Value is determined by HLC timestamp ordering

Implementations

impl<T: Clone> LWWRegister<T>

pub fn new(value: T, clock: &mut HybridClock) -> Self

Create a new LWW-Register with an initial value.

Uses the provided HybridClock for a causally consistent timestamp.

pub fn with_timestamp(value: T, timestamp: HybridTimestamp) -> Self

Create a new LWW-Register with an explicit timestamp.

Useful for testing or deserialization.

pub fn set(&mut self, value: T, clock: &mut HybridClock)

Update the register’s value.

Uses the provided HybridClock for a causally consistent timestamp.

pub fn set_with_timestamp(&mut self, value: T, timestamp: HybridTimestamp)

Update the register’s value with an explicit timestamp.

Only applies if the new timestamp is >= the current one.

pub fn value(&self) -> &T

Get the current value.

pub fn timestamp(&self) -> HybridTimestamp

Get the current timestamp.

Trait Implementations

impl<T: Clone + Clone> Clone for LWWRegister<T>

fn clone(&self) -> LWWRegister<T>

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl<T: Clone> Crdt for LWWRegister<T>

fn merge(&mut self, other: &Self)

Merge another replica’s state into this one.

impl<T: Debug + Clone> Debug for LWWRegister<T>

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl<T: Clone> DeltaCrdt for LWWRegister<T>

type Delta = LWWRegisterDelta<T>

The type of delta produced by this CRDT.

fn delta(&self, other: &Self) -> LWWRegisterDelta<T>

Generate a delta containing changes in self that other does not have.

fn apply_delta(&mut self, delta: &LWWRegisterDelta<T>)

Apply a delta to this replica’s state.

impl<T: Clone + PartialEq> PartialEq for LWWRegister<T>

fn eq(&self, other: &Self) -> bool

Tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl<T: Clone> Versioned for LWWRegister<T>

const CURRENT_VERSION: u8 = 1

Current schema version for this CRDT type’s serialization format.

const CRDT_TYPE: CrdtType = CrdtType::LWWRegister

The CRDT type identifier for the envelope.

impl<T: Clone + Eq> Eq for LWWRegister<T>