Skip to main content

EdgeHistorySlot

Struct EdgeHistorySlot 

Source
pub struct EdgeHistorySlot {
    pub a: EntityId,
    pub rel: TermId,
    pub b: EntityId,
    pub edge: EdgeId,
    pub fact: FactId,
    pub flags: u16,
    pub kind: u16,
    pub recorded_at: u64,
    pub valid_from: u64,
    pub valid_to: u64,
}
Expand description

A temporal typed graph edge version (48-byte slot, Ordered arena, key [a BE | valid_from BE | edge BE]).

Stored twice, in two mirrored history arenas with the same orientation as EdgeSlot. The hot current graph still uses EdgeSlot; this record is the source of truth for historical as_of traversal.

The key is time-ordered per entity, not grouped by relation. An as_of(t) traversal wants the versions valid at one instant, and at most one version of a (a, rel, b) triple is valid at any instant, so grouping by triple forces a walk through every version of every triple to find the few that answer. Ordering by valid_from instead lets the traversal start at t and walk backwards through the versions that most recently became true — the candidates — and stop when it has enough.

Fields§

§a: EntityId

First key component (out-arena: source; in-arena: destination).

§rel: TermId

Interned relation term.

§b: EntityId

Second key component (out-arena: destination; in-arena: source).

§edge: EdgeId

Edge-version id.

§fact: FactId

Provenance fact, or FactId::NONE.

§flags: u16

Edge flags; see edge_flags.

§kind: u16

Reserved for future lifecycle states.

§recorded_at: u64

Knowledge axis: when the edge version was recorded.

§valid_from: u64

Truth axis: start of the edge validity interval.

§valid_to: u64

Truth axis: end of the edge validity interval; VALID_TO_OPEN = current.

Implementations§

Source§

impl EdgeHistorySlot

Source

pub fn active_at(&self, t: u64) -> bool

true when the edge version is active at t.

Source

pub fn is_open(&self) -> bool

true when this version is the current open edge.

Trait Implementations§

Source§

impl Clone for EdgeHistorySlot

Source§

fn clone(&self) -> EdgeHistorySlot

Returns a duplicate of the value. Read more
1.0.0 (const: unstable) · Source§

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

Performs copy-assignment from source. Read more
Source§

impl Copy for EdgeHistorySlot

Source§

impl Debug for EdgeHistorySlot

Source§

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

Formats the value using the given formatter. Read more
Source§

impl Eq for EdgeHistorySlot

Source§

impl PartialEq for EdgeHistorySlot

Source§

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

Equality operator ==. Read more
1.0.0 (const: unstable) · Source§

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

Inequality operator !=. Read more
Source§

impl Slot for EdgeHistorySlot

Source§

const SIZE: usize = edge_hist_at::SIZE

Total size of the record in bytes.
Source§

const KEY_LEN: usize = edge_hist_at::KEY_LEN

Length of the key prefix; sorting and lookups compare only these leading bytes. Must not exceed SIZE.
Source§

fn write(&self, out: &mut [u8])

Serializes the record into out (out.len() == SIZE), filling every byte.
Source§

fn read(bytes: &[u8]) -> Self

Reconstructs the record from bytes (bytes.len() == SIZE).
Source§

impl StructuralPartialEq for EdgeHistorySlot

Auto Trait Implementations§

Blanket Implementations§

Source§

impl<T> Any for T
where T: 'static + ?Sized,

Source§

fn type_id(&self) -> TypeId

Gets the TypeId of self. Read more
Source§

impl<T> Borrow<T> for T
where T: ?Sized,

Source§

fn borrow(&self) -> &T

Immutably borrows from an owned value. Read more
Source§

impl<T> BorrowMut<T> for T
where T: ?Sized,

Source§

fn borrow_mut(&mut self) -> &mut T

Mutably borrows from an owned value. Read more
Source§

impl<T> CloneToUninit for T
where T: Clone,

Source§

unsafe fn clone_to_uninit(&self, dest: *mut u8)

🔬This is a nightly-only experimental API. (clone_to_uninit)
Performs copy-assignment from self to dest. Read more
Source§

impl<Q, K> Equivalent<K> for Q
where Q: Eq + ?Sized, K: Borrow<Q> + ?Sized,

Source§

fn equivalent(&self, key: &K) -> bool

Checks if this value is equivalent to the given key. Read more
Source§

impl<T> ErasedDestructor for T
where T: 'static,

Source§

impl<T> From<T> for T

Source§

fn from(t: T) -> T

Returns the argument unchanged.

Source§

impl<T, U> Into<U> for T
where U: From<T>,

Source§

fn into(self) -> U

Calls U::from(self).

That is, this conversion is whatever the implementation of From<T> for U chooses to do.

Source§

impl<T> ToOwned for T
where T: Clone,

Source§

type Owned = T

The resulting type after obtaining ownership.
Source§

fn to_owned(&self) -> T

Creates owned data from borrowed data, usually by cloning. Read more
Source§

fn clone_into(&self, target: &mut T)

Uses borrowed data to replace owned data, usually by cloning. Read more
Source§

impl<T, U> TryFrom<U> for T
where U: Into<T>,

Source§

type Error = Infallible

The type returned in the event of a conversion error.
Source§

fn try_from(value: U) -> Result<T, <T as TryFrom<U>>::Error>

Performs the conversion.
Source§

impl<T, U> TryInto<U> for T
where U: TryFrom<T>,

Source§

type Error = <U as TryFrom<T>>::Error

The type returned in the event of a conversion error.
Source§

fn try_into(self) -> Result<U, <U as TryFrom<T>>::Error>

Performs the conversion.