Crate waggle_lens_code 

waggle-lens-code — the symbol lens (design doc 20)

Source-code structure, computed once at mint where the artifact is at hand, stored content-addressed beside the snapshot, served everywhere as plain data. This crate is the extraction half: tree-sitter parses the snapshot, each grammar’s tags.scm query marks the definitions, and the result is a flat, compact SymbolOutline — never an AST, never an index, never retained.

The performance discipline (doc 20 §4) is structural here: compiled queries are cached once per process (std::sync::OnceLock), parsers are reused per thread, the outline is an arena (one Vec, one shared name buffer, parent links by index), and the parse tree drops before extraction returns. extract is a pure function of its inputs — no clock, no I/O — so the sans-I/O law holds even though this crate lives outside waggle-core (it must: grammars are C, and this crate is never compiled to wasm; the edge serves precomputed outlines).

Structs

SymbolOutline

The arena. Construction happens in crate::extract; consumers get lookups and the wire form.

Enums

Lang

The languages the v1 lens ships (doc 20 §9): chosen by agent traffic; each addition pays its binary-size cost consciously.

Constants

OUTLINE_CONTENT_TYPE

The outline blob’s content type (doc 20 §3).

WIRE_VERSION

Wire version — pins the (bytes, extractor) → outline function so a future extractor bump mints new outlines without ambiguity (doc 20 §3).

Functions

detect

Detect a supported language from a path — extension first, then the well-known extension-less basenames have no grammar here (they are text-sniffed upstream); a None simply means “no outline”, never an error: the lens degrades to the plain text loop (doc 20 §9).

extract

Extract the symbol outline from source text. Pure: same inputs, same outline, always. Returns an empty outline (callers store no blob) when the text does not parse at all or yields no definitions — degradation is to today’s text loop, never below it.