Struct libocc::Segment

pub struct Segment<T> where
    T: Clone + PartialEq,  { /* fields omitted */ }

A segment is a part of an event log.

It’s a list of events followed by a projection, called a “snapshot”. Creating a new segment will make the former segments snapshot immutable, and a new (mutable) segment is created.

Snapshots allow for faster history traversal, as not the entire event log needs to be replayed in order to project an earlier state, unlike a single-segment event log.

Implementations

impl<T> Segment<T> where
    T: Clone + PartialEq, 

pub fn new() -> Segment<T>

Creates a new segment

The new segment will have a timestamp of the current time, and won’t have any prior history associated with it.

pub fn from_projection(projection: Vec<T>, events: Vec<Event<T>>) -> Segment<T>

Creates a new segment from a given projection and event log at the current time

pub fn get_time(&self) -> &Timestamp

Returns a shared reference to the timestamp of this segment

pub fn get_projection(&self) -> &Vec<T>

Returns the current projection

pub fn project_at_onto(
    &self,
    timestamp: &Timestamp,
    snapshot: Vec<T>
) -> Option<Vec<T>>

Projects the segments events predating a specified timestamp onto a given snapshot

pub fn push(&mut self, event: Event<T>) -> Result<()>

Applies and appends an event to the segments snapshot and log, respectively (checked)

pub fn prepend(&mut self, other: Self) -> Result<()>

Merges two consecutive segments by prepending the other before this one (checked)

pub fn prepend_unchecked(&mut self, other: Self)

Merges two consecutive segments by prepending the other before this one (unchecked)

Trait Implementations

impl<T: Clone> Clone for Segment<T> where
    T: Clone + PartialEq, 

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

Returns a copy of the value.

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

Performs copy-assignment from source.

impl<T: Debug> Debug for Segment<T> where
    T: Clone + PartialEq, 

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

Formats the value using the given formatter.

impl<'de, T> Deserialize<'de> for Segment<T> where
    T: Clone + PartialEq,
    T: Deserialize<'de>, 

fn deserialize<__D>(__deserializer: __D) -> Result<Self, __D::Error> where
    __D: Deserializer<'de>, 

Deserialize this value from the given Serde deserializer.

impl<T> Serialize for Segment<T> where
    T: Clone + PartialEq,
    T: Serialize, 

fn serialize<__S>(&self, __serializer: __S) -> Result<__S::Ok, __S::Error> where
    __S: Serializer, 

Serialize this value into the given Serde serializer.