design-md-consolidation 2: journal entry + roadmap sweep-2 closed

docs/JOURNAL.md

@@ -12537,3 +12537,118 @@ grep must match the spec intent, not just one specific anchor
 form. Future plans for sweeps 2-4 will fold all anchor variants
 (literal Iter-N, bare Nx, prefixed `pre-Nx`, possessive `Nx's`,
 suffix `Nx sketch`, etc.) into one composite grep at plan-time.
+
+## 2026-05-10 — Iteration design-md-consolidation 2: REVERTED + migration + correction history + future speculations
+
+Second iteration of the milestone defined in
+`docs/specs/2026-05-10-design-md-consolidation.md`. Sweep 2 closes
+the "REVERTED + migration plans + correction history + future
+speculations" item: the audit-trail preservation of Decision 7,
+the 7-point Decision 10 Migration plan, the Decision 9
+narrative-of-changes opener, the Decision 11 mono-vs-vdisp
+correction history, and the non-binding future-iter speculations
+are removed or condensed. DESIGN.md now describes only the current
+state plus the timeless rationale; the discarded narratives live
+in JOURNAL (this entry plus the original iter entries that
+recorded each change at the time).
+
+Sections deleted entirely:
+
+- Decision 7 (Term::If REVERTED block) — 32 lines. `Term::If`
+  exists in the language; the witness is the Term-schema
+  section. Decision numbering preserves the gap (Decision 6 →
+  Decision 8) so JOURNAL cross-references remain stable. One
+  orphan cross-reference at line 1141-1144 ("the same trade-off
+  Decision 7 made for `Term::If`'s relationship to nested
+  `Term::Match`") was caught in quality review and replaced with
+  the principle stated directly ("The principle: prefer
+  composability over schema-level rejection where the typecheck
+  rule is unambiguous").
+- Decision 10 §"Migration plan" — 32 lines, 7-point list of past
+  iters (annotation feature → RC runtime → uniqueness inference
+  → reuse hints → drop-iterative → validation bench → advisory
+  lint). The end state is described in the rest of Decision 10.
+
+Paragraphs condensed:
+
+- Decision 9 narrative-of-changes opener ("Originally framed as
+  X; then re-framed as Y; the revision flips Z") → one-line
+  state opener leading into the existing three RC/Boehm/bump
+  bullets.
+- Decision 9 pre-Decision-9 history paragraphs ("Originally,
+  every ADT box, lambda env, and closure pair was allocated
+  with bare malloc and never freed…", and the bridging
+  "`--alloc=bump` mode introduced for the bench is a measurement
+  tool" sentence) — both removed.
+- Decision 11 §"Why mono, not virtual dispatch (the
+  empirically-grounded version)" → state-only form. The
+  substantive rationale ("mono enables optimisations vdisp
+  forbids") survives; the correction history ("The original
+  rationale implicitly argued … the micro-benchmark refutes that
+  specific claim") is dropped. Header simplified to "Why mono,
+  not virtual dispatch."
+
+Future-iter speculations — per-site decisions:
+
+- `A future iter may layer a per-fn-arena optimisation` REMOVED
+  — the per-fn arena is shipped (next subsection describes it).
+  Announcement is history.
+- `A future iter that proposes any of laziness, recursive value
+  bindings, shared mutable state, …` KEPT, TIGHTENED — restructured
+  from "future iter that proposes X must Y" to "X is rejected
+  unless Y" (assertive present-tense form of the same binding
+  constraint).
+- `a future iteration (deferred) makes the explicit annotation
+  mandatory and rejects \`Implicit\`` REMOVED — non-binding
+  aspiration. (Plan named the site as "a later iter (deferred)";
+  actual text was "a future iteration (deferred)" — variance
+  flagged by implementer, edit applied correctly.)
+- `Concrete design deferred until the need materialises` REMOVED
+  — the binding content (no tracing GC backstop, ownership/linear
+  extension) precedes; the "deferred" sentence was the unneeded
+  punchline.
+- `A future milestone may add a Prelude when concrete LLM-author
+  code surfaces a case…` REMOVED first sentence (aspiration), KEPT
+  second sentence (current-state description of how primitive
+  output works today via `io/print_int` / `io/print_bool` /
+  `io/print_str`).
+
+Acceptance:
+
+- composite grep
+  `grep -nE 'REVERTED|preserved for the audit trail|Migration plan|[Oo]riginally framed|original rationale|empirically-grounded version|A future (iter|iteration|milestone|Prelude) may|A future iter that|a (later|future) iter(ation)? \(deferred\)|Concrete design deferred' docs/DESIGN.md`
+  returns empty.
+- Sweep-1 invariant grep stays empty (no regression).
+- `Term::If` present in Term schema (line 1808 — `{ "t": "if", "cond": Term, … }`).
+- `cargo test --workspace` 0 FAILED across all test binaries.
+- `bench/check.py` 0 regressed (63 metrics; 4 improved beyond
+  tolerance, 59 stable); `bench/compile_check.py` 0 regressed (24
+  metrics, 24 stable).
+- DESIGN.md size: 2253 → 2155 lines (−98 lines this sweep, −107
+  cumulatively from 2262 at milestone start).
+
+Tasks (commit subjects):
+
+- design-md-consolidation 2.1: delete Decision 7 (Term::If REVERTED block)
+- design-md-consolidation 2.1 fixup: replace orphaned Decision 7 cross-reference at DESIGN.md:1141-1144
+- design-md-consolidation 2.2: condense Decision 9 narrative-of-changes opener + drop pre-Decision-9 history paragraphs
+- design-md-consolidation 2.3: delete Decision 10 §Migration plan (7-point completed-iter list)
+- design-md-consolidation 2.4: condense Decision 11 mono-vs-vdisp correction history to state-only rationale
+- design-md-consolidation 2.5: future-iter speculations — remove aspirations, tighten binding prohibitions
+
+Carried into sweep 3: schema SoT inversion (DESIGN.md §Data-model
+becomes the canonical schema; ast.rs gains a doc-comment pointing
+to it; new drift test `design_schema_drift.rs` enforces structural
+agreement between schema variants and ast.rs enums). Carried into
+sweep 4: workflow / cross-reference cleanup ("Project ecosystem"
+`agents/` path correction; "Verification and correctness" workflow
+detail; "What is not (yet) supported" §"Recently lifted gates"
+removal; cross-reference audit).
+
+Process note: Sweep 2's plan-time composite grep matched the
+spec's full intent on the first attempt — only one fixup commit
+(2.1, for the orphan Decision 7 cross-reference, which was a
+content-not-grep issue caught by quality review). The Sweep 1
+lesson held. One plan-vs-actual phrasing variance ("a later iter"
+vs "a future iteration") was caught by the implementer at edit
+time and applied correctly without a fixup.

docs/roadmap.md

@@ -40,7 +40,7 @@ work progresses.
   - context: `docs/specs/2026-05-10-design-md-consolidation.md`
   - sub-entries:
     - [x] Sweep 1 — remove history anchors
-    - [ ] Sweep 2 — REVERTED + migration plans out
+    - [x] Sweep 2 — REVERTED + migration plans out
     - [ ] Sweep 3 — schema SoT inversion + data-model hardening
     - [ ] Sweep 4 — workflow / cross-reference cleanup