Struct ditto::register::Register

pub struct Register<T: Clone> { /* fields omitted */ }

A Register is a replaceable value that can be updated via the update function.

Register allows op-based replication via execute_op and state-based replication via merge. Both replication methods are idempotent and can handle out-of-order delivery.

Register has a spatial complexity of O(N + S), where N is the number of values concurrently held in the Register and S is the number of sites that have updated the Register. It has the following performance characteristics:

• update: O(1)
• execute_op: O(N), where N is the number of values concurrently held in the Register.
• merge: O(N + M), where N and M are the number of values concurrently held in the Register being merged into and the RegisterState being merged, respectively.

Methods

impl<T: Clone> Register<T>

pub fn new(value: T) -> Self

Constructs and returns a new Register with site id 1.

pub fn get(&self) -> &T

Returns a reference to the Register's value.

pub fn update(&mut self, value: T) -> Result<Op<T>, Error>

Updates the Register's value and returns an op that can be replciated to other sites. If the register does not have a site id allocated, it caches the op and returns an AwaitingSiteId error.

pub fn execute_op(&mut self, op: Op<T>) -> &T

Executes an Op and returns a reference to the new value if the value has changed. If the op has already been executed or superceded, nothing is done.

pub fn merge(&mut self, other: RegisterState<T>)

Merges remote state into the Register

pub fn add_site_id(&mut self, site_id: SiteId) -> Result<Option<Op<T>>, Error>

Assigns a site id and returns a cached op if it exists.

pub fn site_id(&self) -> SiteId

Returns the Register's site id.

pub fn summary(&self) -> &Summary

Returns a reference to the Register's summary.

pub fn state(&self) -> RegisterState<T>

Returns a borrowed RegisterState.

pub fn clone_state(&self) -> RegisterState<'static, T>

Returns an owned RegisterState of cloned values.

pub fn into_state(self) -> RegisterState<'static, T>

Consumes the Register and returns its RegisterState

pub fn from_state(
    state: RegisterState<T>,
    site_id: Option<SiteId>
) -> Result<Self, Error>

Constructs a new Register from a RegisterState and an optional site id. If the site id is given, it must be nonzero.

pub fn validate_and_execute_op(
    &mut self,
    op: Op<T>,
    site_id: SiteId
) -> Result<&T, Error>

Validates that an op comes from a specific site id, then executes the op.

Trait Implementations

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

fn fmt(&self, __arg_0: &mut Formatter) -> Result

Formats the value using the given formatter.

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

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

Returns a copy of the value.

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

Performs copy-assignment from source.

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

fn eq(&self, __arg_0: &Register<T>) -> bool

This method tests for self and other values to be equal, and is used by ==.

fn ne(&self, __arg_0: &Register<T>) -> bool

This method tests for !=.