Struct FusionEngine 

pub struct FusionEngine { /* private fields */ }

The fusion engine that combines candidates from multiple modalities

Implementations

impl FusionEngine

pub fn new(config: FusionConfig) -> Self

Create a new fusion engine

pub fn fuse( &self, vector_candidates: Option<FilteredCandidates>, bm25_candidates: Option<FilteredCandidates>, ) -> FusionResult

Fuse candidates from vector and BM25 search

INVARIANT: Both candidate sets are already filtered to AllowedSet. This function does NOT apply any additional filtering.

This is the two-lane convenience over FusionEngine::fuse_multi: it builds weighted lanes from the configured method weights and delegates, so the two-lane and N-ary paths share exactly one scoring implementation.

pub fn fuse_multi(&self, lanes: Vec<WeightedLane>) -> FusionResult

N-ary fusion across any number of pre-filtered modality lanes.

This is the canonical multi-lane path: vector, BM25, and grep (or any future lane) are fused by a single call. RRF funnels through fuse_rrf_weighted; Linear and Max combine per-lane normalized scores weighted by each lane’s weight.

INVARIANT: every lane is already filtered to the AllowedSet. No additional filtering happens here.