Struct WangRefIndex 

pub struct WangRefIndex { /* private fields */ }

Prebuilt single-reference index for WangMatcher.

WangMatcher::match_one rebuilds the reference’s inverted index on every call (SortedPostings::build is O(R log R) per match — audit C1). When the same reference is matched repeatedly (batch 1:1, query loops against a fixed catalog, streaming identification), build the WangRefIndex once and call WangMatcher::match_one_prebuilt; the per-query cost then drops to the pure O(Q log U + range) voting pass, and the index applies the same stop-hash filter the 1:1 path would.

The two entry points are guaranteed to agree: match_one is defined as build-then-match_one_prebuilt, so results are identical by construction.

Implementations

impl WangRefIndex

pub fn build(reference: &WangFingerprint, cfg: &WangMatchConfig) -> Option<Self>

Build the index for reference using the stop-hash policy from cfg (max_postings_per_hash). Returns None when the reference has no hashes or every hash is filtered out — the same conditions under which match_one returns MatchResult::NONE.