meow-memorizing

wasm-matcher

WebAssembly backend for the page word scanner. Replaces the JS O(text × words) indexOf loop with a single-pass Aho-Corasick scan.

Responsibility

• Build and cache two Aho-Corasick automata (active + deleted word lists) keyed by the current word set, rebuilt only when the set changes.
• Scan a text node’s string once, applying ASCII word-boundary checks and returning matches as { index, word, end }, the contract the JS caller in src/content-scripts/matcherFacade.ts consumes.

DOM traversal and rendering stay in JS; this crate is pure text computation.

Boundary

#[wasm_bindgen] exports (see src/lib.rs):

• set_words(active, deleted) — (re)build cached automata.
• find_matches(text) — matches against active words.
• find_deleted_matches(text) — matches against deleted words.

Match semantics: leftmost-longest, non-overlapping, ASCII case-insensitive, both flanks non-[a-zA-Z]. Returned word preserves the source casing.

Build

cargo test -p wasm-matcher runs native unit tests. Browser artifacts are produced by scripts/build-wasm.sh (wasm32 release + wasm-bindgen) and inlined as base64 by scripts/inline-wasm.ts. See repo AGENTS.md.

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