release: promote v0.18.0 to main

README.md

@@ -395,7 +395,7 @@ row inspects the *toolpath*, the bottom row presents the *source model* (see
 
 Design rationale, boundaries, and the accepted architecture live in
 [`docs/design/`](docs/design); the [docs index](docs/README.md) maps the whole set. Fourteen
-packages publish to npm in lockstep (currently **v0.17.0**) with npm provenance.
+packages publish to npm in lockstep (currently **v0.18.0**) with npm provenance.
 
 ## Development
 

docs/design/DD-017-rs274ngc-parametric-programs.md

@@ -1,8 +1,11 @@
 # DD-017 — RS274NGC parametric programs: parameters, expressions & O-word flow (#189 phase 7)
 
-**Status:** **Proposed** <!-- Draft | Proposed | Accepted | Superseded | Rejected -->
+**Status:** **Accepted (Phases 1–2)** — Phase 1 (parameters + expressions, D2/D3, §5.1) and Phase 2
+(O-word control flow — conditionals + bounded loops, D4/D5/D6 for `if`/`while`/`do`/`repeat`, §5.2) both
+accepted & built 2026-08-27; **Phases 3–4 (subroutines, capability/docs polish) remain Proposed**, gated
+on measured Phase 2 results. <!-- Draft | Proposed | Accepted | Superseded | Rejected -->
 **Authors/Owners:** Nathaniel Chestnut
-**Date:** 2026-07-29 · **Last revised:** 2026-07-29
+**Date:** 2026-07-29 · **Last revised:** 2026-08-27
 **Owning Epic:** #189 (non-extrusion toolpath coverage), **phase 7** · **Milestone:** Future
 **Supersedes / Superseded by:** none
 **Related:** [DD-012](./DD-012-non-extrusion-toolpath-and-modal-tool-state.md) (non-extrusion move model — this extends its parser work; §16 spec anchors), [RR-004](../research/RR-004-non-extrusion-toolpath-coverage.md) §9 (spec landscape), DD-010 (motion interpreter this builds on), DD-003 (parser resource limits — this adds two), DD-001 (capability/confidence model). Reference spec: **RS274NGC / NIST IR 6556** (free), as-implemented by the **LinuxCNC G-code reference** (cited as behavioral parity, no text copied — RR-004 §6).
@@ -202,3 +205,5 @@ the existing SoA). No renderer/adapter/color changes (they consume the same segm
 | Date | Decision | By |
 |---|---|---|
 | 2026-07-29 | DD-017 drafted as **Proposed** (D1–D8 open). Phase 7 of #189; the spec-derivable RS274NGC programming layer (params/expressions/O-words) flagged during real-file validation. Follows DD-012 §16 (spec-anchored CNC). | Chestnut Labs |
+| 2026-08-27 | **Phase 1 accepted & built** (parameters + expressions only; D2/D3/§5.1). New `packages/gcode-parser/src/rs274.ts` — a pure recursive-descent evaluator (RS274NGC operator/function set, degree trig, LinuxCNC MOD/EQ semantics, `MAX_EXPR_DEPTH` guard, no `eval`) + parameter store (numbered/named/global, indirect `##`, computed `#[expr]`, read-only system-param allow-list `#5420–#5422`), gated on a per-line `#`/`[` scan (FDM byte-identical, native goldens regenerated for the additive `parametricProgram` capability only; ~2.7% parse overhead from the gate, measured on 3DBenchy). O-word control flow (D4, Phases 2–4) explicitly **not** authorized until Phase 1 results are reviewed. | Chestnut Labs (lead) |
+| 2026-08-27 | **Phase 2 accepted & built** (O-word control flow — conditionals + bounded loops; D4/D5/D6, §5.2). New `packages/gcode-parser/src/rs274-flow.ts` — the program-buffered interpreter of D1 Option A: engaged only when `programUsesOWords(text)` (a cheap char-scan; FDM never enters it, byte-identical), it buffers the program, builds a **block tree**, and executes `if`/`elseif`/`else`/`endif`, `while`/`endwhile`, `do`/`while`, `repeat`/`endrepeat`, `break`/`continue` — re-feeding each plain line through the same `processLine` (one geometry path) and evaluating conditions/counts against the shared Phase-1 store (`Rs274Context.evalExpression`). **Bounded execution (D5):** new public `maxProgramIterations` limit (default 1M) charged per loop-body pass → `rs274-iteration-limit` + partial IR; internal `MAX_CONTROL_NESTING` cap; loops are iteration, not recursion, so only structural nesting (capped) uses JS stack — a hostile `o while [1]` wastes only bounded CPU, cannot hang/OOM/stack-overflow. **Honesty (D6):** clean flow → `parametricProgram: 'known'`; a degraded run (hit cap / unbalanced / unsupported / malformed condition) → `'approximated'` + a specific disclosure. `sub`/`call`/`return` disclosed unsupported and **not** executed (Phase 3). Streaming discloses + runs linearly (a partial stream can't re-run a line range, §4.1). Both golden suites unchanged; validated on a real LinuxCNC-idiom `while`-loop bolt circle (params + degree trig + flow). `maxCallDepth` (subroutine recursion) deferred to Phase 3. | Chestnut Labs (lead) |