Struct EventStreamHead 

pub struct EventStreamHead {
    pub mmr: Vec<U256>,
    pub checkpoint_seq: u64,
    pub num_events: u64,
}

Available on crate feature unstable only.

On-chain head of an authenticated event stream.

The framework maintains one of these per event stream as a dynamic field on the accumulator root object (0xacc), keyed by accumulator::Key<accumulator_settlement::EventStreamHead> { owner: stream_id }. Use derive_event_stream_head_object_id to compute the dynamic field’s object id from the stream id.

Each settlement transaction that processes events for the stream folds a per-checkpoint merkle tree root into the MMR using carry-propagation. The framework guarantees at most one such settlement per stream per checkpoint, so checkpoint_seq strictly identifies which checkpoint the head reflects.

Mirrors sui::accumulator_settlement::EventStreamHead.

BCS

event-stream-head = vector u256 u64 u64

Fields

mmr: Vec<U256>

Merkle Mountain Range peaks, ordered from the lowest level upward. Empty slots hold U256::ZERO; the vector grows by one slot whenever the carry propagates past the current highest level.

checkpoint_seq: u64

The latest checkpoint whose events have been folded into the MMR.

num_events: u64

Total number of events ever folded into the MMR.

Trait Implementations

impl Clone for EventStreamHead

fn clone(&self) -> EventStreamHead

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for EventStreamHead

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

Formats the value using the given formatter.

impl Default for EventStreamHead

fn default() -> EventStreamHead

Returns the “default value” for a type.

impl<'de> Deserialize<'de> for EventStreamHead

fn deserialize<__D>(__deserializer: __D) -> Result<Self, __D::Error>

where __D: Deserializer<'de>,

Deserialize this value from the given Serde deserializer.

impl PartialEq for EventStreamHead

fn eq(&self, other: &EventStreamHead) -> 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 Serialize for EventStreamHead

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

where __S: Serializer,

Serialize this value into the given Serde serializer.

impl Eq for EventStreamHead

impl StructuralPartialEq for EventStreamHead