Struct VecReduceBackend 

pub struct VecReduceBackend<K, V, W, T, R, L> { /* private fields */ }

A reference ProxyReduceBackend over VBatch storage.

Implementations

impl<K, V, W, T, R, L> VecReduceBackend<K, V, W, T, R, L>

pub fn new(logic: L) -> Self

A backend deferring value semantics to logic, covering the key space in windows.

pub fn with_window(logic: L, window_size: usize) -> Self

A backend with an explicit window budget, in presented records.

Trait Implementations

impl<K, V, W, T, R, L> ProxyReduceBackend<T, Rc<ChunkBatch<VecChunk<u64, (K, V), T, R>>>, Rc<ChunkBatch<VecChunk<u64, (K, W), T, R>>>> for VecReduceBackend<K, V, W, T, R, L>

where K: Ord + Clone + Hash + 'static, V: Ord + Clone + 'static, W: Ord + Clone + Hash + 'static, T: Lattice + Timestamp, R: Semigroup + Ord + Clone + 'static, L: FnMut(&K, &[(V, R)], &mut Vec<(W, R)>, &mut Vec<(W, R)>),

type Key = u64

Independent groups, with identities stable across retires.

type VIn = u64

Input value proxies, valid throughout a window.

type VOut = u64

Output value proxies, including newly produced values, valid throughout a window.

type RIn = R

Diff type presented for the input.

type ROut = R

Diff type of the output.

fn begin(&mut self, _description: Description<T>)

Initiate a session to create batches for these descriptions, which span [lower, upper).

fn next_window( &mut self, instance: &ReduceInstance<'_, T, Rc<ChunkBatch<VecChunk<u64, (K, V), T, R>>>, Rc<ChunkBatch<VecChunk<u64, (K, W), T, R>>>>, changed: &[u64], from: &mut KeyPosition<u64>, window: &mut ReduceWindow<T, R, R>, )

Present the next window of the key space, and advance from past it.

fn reduce_corrections( &mut self, keys: &[u64], in_ends: &[usize], input: &[(u64, R)], out_ends: &[usize], output: &[(u64, R)], ) -> (Vec<(u64, R)>, Vec<usize>)

A wave of input-output reconciliation, in which the backend supplies necessary edits.

fn emit(&mut self, records: &[((u64, u64), T, R)])

Commit a collection of updates to the batch in progress.

fn finish(&mut self) -> Option<Rc<ChunkBatch<VecChunk<u64, (K, W), T, R>>>>

Complete the session matching begin, yielding the batch it described, or None when the span it described carries no updates.