Six-task post-fieldtest documentary tidy. No production-code behaviour
changes; 559 tests green at every per-task gate.
T1-T3: form_a.md additions
- §Definitions intro "Three kinds" -> "Five kinds".
- New `### Class — (class ...)` subsection: EBNF carries optional
superclass (0 or 1 per ClassDef.superclass schema), method
signatures with optional defaults; anchored to
examples/test_22c_user_class_e2e.ail (ok 24/2).
- New `### Instance — (instance ...)` subsection: EBNF carries the
(method NAME (body LAM-TERM))* shape; canonical-form CLASS-REF
rule explicitly stated (bare same-module / qualified cross-module);
two examples — same-module abbreviated from
mq3_class_eq_vs_fn_eq_classmod.ail and cross-module qualified
from show_user_adt.ail; bare-cross-module-class-ref diagnostic
named inline.
- §Types `(forall ...)` line extended with optional `(constraints
(constraint CLASS-REF TYPE)+)?` clause; explanatory paragraph
added with no-instance diagnostic anchor; fifth example added
to the Examples block anchored to cmp_max_smoke.ail.
T4: docs/specs/2026-05-13-form-a-default-authoring.md "seven
carve-outs" → "eight carve-outs" at 6 sites contradicting the
§C4(b) compile-time-embed amendment (commit 9fcda8b). Sites:
preamble line 11, §C1 line 170, §C2 line 191, §C3 line 218,
§"Data flow" lines 363 + 374. Post-edit grep returns 4 surviving
"seven" lines (233, 238, 463, 469), all correctly §C4(a)-scope
or arithmetic/future-state.
T5: crates/ailang-core/src/hash.rs:50-57 — delete empty
`#[cfg(test)] mod tests {}` placeholder + 6-line relocation
comment. Tests live in crates/ailang-core/tests/hash_pin.rs
since form-a.1 T5; placeholder served no purpose. hash_pin.rs
still 10/10 passing.
T6: crates/ailang-surface/tests/round_trip.rs — module-level
`//!` and inner `///` docstrings rewritten to the post-T10
four-property framing (parse-determinism / idempotency /
CLI-pipeline-idempotency / carve-out-anchor) instead of the
retired Direction-1/Direction-2 language. Sibling-crate
breadcrumbs added pointing at the other two enforcement points
(roundtrip_cli.rs, carve_out_inventory.rs).
Drift item B2 (audit-form-a "plan file two sites") dropped per
recon verification: docs/plans/2026-05-13-iter-form-a.1.md
contains zero defective "seven" sites; all four hits are
internally scoped to §C4(a), arithmetic, or future-state.
Decision recorded in the journal.
Closes 2 of 3 fieldtest-form-a spec_gap findings (#2 form_a.md
typeclass surface + #3 form_a.md class-qualifier rule for
instance) and 3 of 4 audit-form-a drift items.
First half of the form-a-default-authoring milestone-close iter
(Boss-decided strategy C, big-bang). All five tasks DONE; cargo
test --workspace green at every per-task boundary.
T1 — Add three new tests:
- parse_is_deterministic_over_every_ail_fixture (round_trip.rs)
- cli_parse_then_render_then_parse_is_idempotent (roundtrip_cli.rs)
- carve_out_inventory.rs (new file; #[ignore]'d until T8 deletion)
T2 — Bulk-render the 99 missing examples/<stem>.ail files via
`ail render`. Corpus 58 .ail (pre-iter) -> 157 .ail. Eight .ail.json
carve-outs (7 §C4(a) subject-matter + 1 §C4(b) prelude) preserved.
One re-loop triggered: load_workspace prefers .ail siblings since
ext-cli.1, so the newly-rendered imports broke seven Group-A entries
whose JSON entry-paths now resolved imports to fresh .ail. Repair:
pre-emptive forward-pull of five T3 migrations + 4 transient
#[ignore]s on workspace.rs mod tests (cleanly relocated in T5).
T3 — 14 Group-A test files migrated from ailang_core::load_workspace
to ailang_surface::load_workspace + .ail paths. Carve-out lines
preserved verbatim (7 sites in typeclass_22b2.rs / typeclass_22b3.rs).
T4 — 12 Group-B test files: bulk regex flip on build_and_run /
build_and_run_with_alloc / build_and_run_with_rc_stats call sites
(~70 e2e.rs invocations + 11 subprocess sites). Four files
mis-classified Group-A as Group-B in plan recon (mono_hash_stability,
prelude_free_fns, print_mono_body_shape, show_mono_synthesis); two
files mis-classified Group-B as Group-A (mono_recursive_fn,
mono_xmod_qualified_ref). Migrated per actual shape, not plan label.
T5 — Relocated #[cfg(test)] mod tests from production source to
integration test crates with ailang-surface dev-dependency:
- crates/ailang-core/tests/hash_pin.rs (10 tests from hash.rs)
- crates/ailang-core/tests/workspace_pin.rs (10 non-carve-out tests
from workspace.rs)
- crates/ailang-codegen/tests/eq_primitives_pin.rs (3 tests from
codegen/src/lib.rs:3717-3799)
- ailang-prose/tests/snapshot.rs migrated (helper + 8 fixtures) to
.ail + ailang_surface::load_module
Carve-out tests in workspace.rs mod tests preserved in-place
(3× 22b2 + 3× ct1 = 6 tests). Tempdir-based loader-mechanism tests
(3 sites) also preserved — they don't consume examples/.
Tests: 560 passed, 0 failed, 4 ignored (was 558 + 3 T1 new -
1 transit carve_out_inventory #[ignore] = 560 active).
Tasks 6-12 (bench-driver suffix flips, e2e diff-test rewrite + 4
additional raw-JSON-inspect handlers, .ail.json deletion, retiring
obsolete roundtrip tests + schema_coverage corpus flip, §C3
DESIGN.md restatement, §A4 doctrine edits, WhatsNew + roadmap
strike) ship in the next dispatch on this iter ID.
Known debt inherited to T6-12: 4 raw-JSON-inspect tests in e2e.rs
(borrow_own_demo / reuse_as_demo / render_parse_round_trip_canonical
/ ail_run_accepts_ail_source_with_same_stdout_as_ail_json dual-form
smoke) need rewrite or #[ignore] before T8 deletion; recorded in
journal Concerns + Known debt sections.
Ships class Show a where show : (a borrow) -> Str in the prelude
plus primitive Show Int / Bool / Str / Float instances. Each
instance body is a single-application lambda invoking the
corresponding runtime primitive (int_to_str, bool_to_str,
str_clone, float_to_str) — first prelude instance bodies to call
runtime primitives directly. Float is included in Show (unlike
Eq/Ord) because textual representation is well-defined modulo the
NaN-spelling caveat at DESIGN.md §Float semantics.
The 22b typeclass test corpus is migrated preemptively: 21 fixture
files and 6 consumer files (typeclass_22b{2,3}.rs +
hash.rs ct4 pin + workspace.rs iter22b1 tests + the
instance_present.prose.txt snapshot) rename class Show / show
to class TShow / tshow, analogous to the existing TEq/TOrd
convention. Migration runs before the prelude additions so the
workspace stays green throughout.
Three new tests pin the post-mono shape: show_mono_synthesis.rs
(existence of show__Int/Bool/Str/Float as Def::Fn entries in the
prelude post-mono module), show_dispatch_pin.rs (bare show and
tshow both Step-2 singletons workspace-globally),
mono_hash_stability.rs::primitive_show_mono_symbol_hashes_stay_bit_identical
(body hashes pinned for the 4 new mono symbols).
DESIGN.md §Prelude (built-in) classes drops Show from the
deferred-features list and appends a milestone-24 paragraph
naming the class signature + the 4 instances + the body shape.
print rewire stays deferred to iter 24.3.
Tests: 552 passed (was 548 + 4 new). bench/compile_check +
bench/cross_lang exit 0. bench/check exits 1 on the recurring
noise envelope per the conservative-call lineage.
Closes the module-qualified-class-names milestone. Deletes the
workspace-load workaround; the two-libraries case now resolves via
type-driven dispatch at the call site with explicit qualifier as the
LLM-author's disambiguation tool. Resolves both mq.2 known-debt items
(active_declared_constraints plumbing, (class,method) re-key). New
synth warnings channel emits class-method-shadowed-by-fn at all three
fn-precedence branches per spec section Class-fn collisions. Three new
E2E fixtures + integration tests cover the ambiguous, qualified, and
class-fn-shadow trajectories. DESIGN.md class-names paragraph rewritten,
new section Method dispatch added. Roadmap P2 marked done, milestone-24
unblocked for re-brainstorm.
9/9 tasks. 545 tests green. bench/compile_check.py + cross_lang.py
exit 0; bench/check.py exit 1 (2 noise-class regressions, runtime
uncoupled to typecheck iter).
Three schema fields move bare → canonical (bare for same-module,
<module>.<Class> for cross-module): InstanceDef.class,
Constraint.class, SuperclassRef.class. Symmetric to ct.1's
Type::Con.name rule. ClassDef.name stays bare.
validate_canonical_type_names gains three field-walks via new
check_class_ref helper + two sibling diagnostics
BareCrossModuleClassRef / BadCrossModuleClassRef.
check_class_name_fields narrowed to ClassDef.name-only.
Workspace-internal class-name keys all qualified:
class_def_module, class_by_name, registry entries.0,
ClassMethodEntry.class_name, class_superclasses, mono's
class_index, Origin::Class.class_name. New qualify_class_ref
helper at workspace.rs scope plus sibling
qualify_class_ref_in_check in ailang-check.
Two new positive on-disk fixtures (mq1_xmod_constraint_class{,_dep})
exercise the qualified Constraint.class shape.
Recon claim that all existing fixtures' class-refs are intra-module
was empirically wrong — 10 fixtures required minimal canonical-form
migration. Duplicate-instance test architecturally restructured:
post-mq.1 orphan-freedom makes two-modules-on-same-(class,type)
structurally impossible; new test_22b1_dup_same_module fixture
lands both instances in the class's module.
Plan defects fixed inline: Origin::Class.class_name single
construction site (plan recon off-by-one); build_class_index in
mono.rs needed qualifying; build_module_globals needed Def::Instance
carve-out; check_fn declared-constraint matching needed inline
canonical-form lifting; NoInstance Float-aware message arm needed
prelude.Eq/prelude.Ord match; coherence type-leg needed qualified-
head split-and-lookup. Tasks 3-6 ran as one coherent fix.
7/7 tasks, 520 tests green. bench/compile_check.py + cross_lang.py
exit 0; bench/check.py exit 1 (4 improvements-beyond-tolerance,
audit-ratifiable, not a regression).
MethodNameCollision + dispatch path unchanged; iters mq.2 + mq.3
land them.
Closes the loop opened by this morning's .ailx → .ail rename. Every
path-taking ail subcommand (check, build, run, manifest, render,
prose, merge-prose, describe, emit-ir, diff, workspace, deps) now
accepts a .ail (Form A) input as well as .ail.json (Form B). For
.ail paths the subcommand parses through ailang_surface::parse
in-line and proceeds with the same loaded Module value .ail.json
would have produced; binary semantics are extension-agnostic.
Architecture: a new ailang_surface::{load_module, load_workspace}
pair dispatches on file extension. A new injection point
ailang_core::workspace::load_workspace_with<F> lets the surface
crate plug in an extension-aware loader without core having to
import surface (which would close a crate cycle). Import resolution
in workspace::visit now prefers a .ail sibling over a .ail.json
sibling. The CLI binary's 18 callsites switched to the surface
loaders. Surface parse failures route through
workspace_error_to_diagnostic as a new SurfaceParse variant of
WorkspaceLoadError, so `ail check --json foo.ail` on a malformed
.ail returns a parseable JSON diagnostic with code
surface-parse-error instead of the misleading
`json: expected value at line 1 column 1` fall-through.
Boss pre-commit correction: the implementer followed the plan
verbatim and used snake_case `surface_parse_error`, but every
existing diagnostic code in the codebase is kebab-case (verified
via `git grep` over crates/ailang-check/src and crates/ail/src);
realigned to `surface-parse-error` at three sites (the diagnostic
arm + two ct1 test strings). Journal Concerns section records
the correction.
Tests: cargo test --workspace 487 green (+7 from this iter:
1 core unit, 4 surface integration, 1 ail E2E pair, 1 ct1 CLI
diagnostic-shape). bench/check.py, compile_check.py, cross_lang.py
clean on re-run; the latency.{explicit,implicit}_at_rc tail
cluster occasionally flagged on first runs is the same
nondeterministic cluster the previous two audits documented;
baseline left pristine for the third consecutive iter.
Roadmap follow-up "ail check/build/run accept .ail extension" (P2)
removed.
DESIGN.md §Decision 6 / "CLI" bullet gained the symmetric upward
sentence: both .ail and .ail.json are first-class CLI inputs.
Five polymorphic prelude free fns (ne/lt/le/gt/ge) plus three E2E
fixtures: positive composition over Int/Bool/Str, user-ADT with
user-written Eq/Ord on IntBox, and Float-NoInstance with a
Float-aware diagnostic addendum cross-referencing DESIGN.md §"Float
semantics".
Two checker-side fixes were needed alongside the prelude additions,
both symmetric to the iter 23.4-prep visibility fix:
- linearity::check_module_with_visible — workspace-aware callee-mode
resolution so a Borrow-mode user fn forwarding into a prelude poly
fn (e.g. `at_most x y = not (gt x y)`) doesn't false-fire
consume-while-borrowed.
- mono::collect_mono_targets — distinguish rigid forall vars from
unbound metavars; rigid-bearing free-fn targets skip (they get
re-collected with concrete subst when the enclosing fn itself
monomorphises). Without this, a polymorphic body calling another
polymorphic free fn produced a spurious __Unit specialisation
whose body referenced compare at Unit.
Roadmap split: shipped Eq/Ord half checked, Show + print-rewire half
remains pending behind the heap-Str ABI prerequisite. DESIGN.md
§"Prelude classes" amended.
One pre-existing fixture (test_22b1_missing_method) renamed its
class method ne → tne to avoid collision with the new prelude `ne`.
Bench: check.py + cross_lang.py exit 0; compile_check.py exits 1
with one sub-ms check_ms.local_rec_capture at +26% (tolerance 25%) —
prelude-growth-related noise-band fluctuation, ratifiable per spec
§248-249 and journal Concerns.
Three Minor items from the ct.1.5a quality review:
1. normalize_type_for_registry now recurses into
Type::Forall.constraints[].type_, symmetric to walk_type. Closes a
latent gap: a Forall with bare cross-module constraint types reaching
the registry would have produced a key disagreeing with the qualified
form. RED test: ct1_5a_normalize_recurses_into_forall_constraints.
2. Documented the bare-name limitation on Registry::type_def_module:
two modules each defining 'type Foo' collide at insert; the proper
fix (re-key as (owning_module, bare_name)) is out of ct.1's scope.
3. Removed the four iter-tag explanatory paragraphs at the
normalize_type_for_lookup call sites (check/lib.rs check_fn,
mono.rs three sites). Replaced each with a one-line pointer to the
helper's docstring per project comment policy.
Adds BareCrossModuleTypeRef / BadCrossModuleTypeRef / QualifiedClassName
to WorkspaceLoadError plus the validate_canonical_type_names function
that enforces the canonical-form rule on every Type::Con name reachable
from any def (including Term::Lam.param_tys / .ret_ty and Term::LetRec.ty).
Term::Ctor.type_name and class-name fields land in Tasks 2 + 3; the
validator is not yet wired into load_workspace (Task 6). Seven RED-first
unit tests cover the cases enumerated in spec section Testing strategy
plus a Lam-embedded-type smuggle-prevention test.
main.rs gains diagnostic arms for the three new variants to keep the
exhaustive match compiling.
The auto-loaded prelude (iter 23.2 work-in-progress) injects
`class Eq` plus three primitive instances (Eq Int, Eq Bool, Eq Str)
into every workspace. Five workspace::tests assertions broke against
this new baseline:
- iter22b1_missing_method_fires_diagnostic
- instance_without_superclass_instance_fires
- instance_overriding_nonexistent_method_fires
Their fixtures redeclare `class Eq` (and `class Ord` in one case),
which now collides with the prelude. Renamed each fixture's
`Eq`/`eq` -> `TEq`/`teq` and `Ord`/`lt` -> `TOrd`/`tlt`, matching
the scheme already used in the two earlier-renamed test_22b2
fixtures. Method `ne` stays (does not collide). Assertion strings
in workspace.rs updated to match.
- iter22b1_workspace_with_no_classes_has_empty_registry
- iter22b1_instance_in_class_module_loads_clean
Their asserted registry counts assumed an otherwise-empty registry.
Rewritten to filter by `defining_module != "prelude"`: the property
is "no NON-prelude entries" / "exactly one fixture-owned entry",
not raw count.
Doc comments updated alongside each assertion change so the rationale
for TEq/TOrd (collision avoidance) is local. No production code
touched.
Address quality review of a9aa248:
- Replace string-prefix discriminator (`prior.starts_with("class ")`)
with a structural `Origin { Class | Fn }` enum; `kind` is now a
`match` on variants, formatting is reserved for error construction.
- Fix fn-fn collision misreport: in the `Def::Fn` arm, only fire
`MethodNameCollision` when the prior origin is a class. Two
`Def::Fn` with the same name are `CheckError::DuplicateDef`'s job
in `ailang-check`, not this pre-pass.
- Tests use `examples_dir()` like the rest of the module; path
construction is no longer ad-hoc.
- Tests assert `first_origin` / `second_origin` so an origin-format
regression cannot silently break the `kind` discriminator.
- Drop forward-looking 22b.4 prelude reservation note from the
variant doc — keep only what's load-bearing for 22b.2.
Adds seven fixtures under examples/test_22b1_* exercising the
workspace-load coherence checks plus four positive/negative tests in
ailang-core/src/workspace.rs:
- iter22b1_instance_in_class_module_loads_clean: positive case;
test_22b1_orphan_class.ail.json declares Show + instance Show Int
in the same module (the class's). Registry has one entry.
- iter22b1_orphan_instance_fires_diagnostic: declares Show in
test_22b1_orphan_third_classmod, declares instance Show Int in
test_22b1_orphan_third (a third module). Fires OrphanInstance.
- iter22b1_duplicate_instance_fires_diagnostic: per the JOURNAL hint,
module A defines class Show + instance Show MyInt (legal, A is
class's module), module B defines type MyInt + instance Show MyInt
(legal, B is type's module). Entry imports both. Fires
DuplicateInstance with first/second_module distinct.
- iter22b1_missing_method_fires_diagnostic: class Eq with two
non-default methods (eq, ne), instance Eq Int specifies only ne.
Fires MissingMethod { method: "eq" }.
The surface round-trip gate (ailang-surface/tests/round_trip.rs)
filters out test_22b1_* fixtures because the Form-B parser arms for
ClassDef/InstanceDef are deferred to 22b.4. Without the filter, every
fixture's printed text would re-parse-fail on the unknown `class` /
`instance` head.
Test count: 291 → 295 (4 new workspace tests, all green).
Adds the workspace-global typeclass instance registry per Decision 11
"Resolution and monomorphisation". Built at the end of load_workspace
after the DFS over imports completes; keyed by (class-name, type-hash)
where type-hash uses the new canonical::type_hash (16-hex prefix,
parallel to def_hash and module_hash).
Three coherence checks fire from build_registry, each surfacing as a
distinct WorkspaceLoadError variant:
- OrphanInstance: `instance C T` not in C's or T's defining module.
- DuplicateInstance: two entries share the same (class, type-hash) key.
- MissingMethod: instance omits a required (non-default) method.
The CLI's workspace_error_to_diagnostic is extended with the three new
codes (orphan-instance / duplicate-instance / missing-method).
All existing Workspace { ... } construction sites get the new
`registry` field, defaulting to Registry::default() at synthetic /
test-only paths and threading through ws.registry.clone() at codepath
sites that already hold a real workspace.
Includes hash-stability regression tests (iter22b1_schema_extension_*
and iter22b1_classdef_empty_optionals_hash_stable) and the empty-
registry positive test against examples/sum.ail.json. Test count:
288 → 291 (3 new tests, all pass).
Adds Def::Class(ClassDef) and Def::Instance(InstanceDef) variants per
Decision 11 §"Form-A schema". All optional fields (superclass, doc,
default body) carry skip_serializing_if so canonical-JSON bytes of
pre-22b fixtures stay bit-identical.
Downstream match-on-Def sites are extended with explicit Class/Instance
arms. Behaviour for 22b.1 is placeholder (skip in typecheck/codegen,
one-line summary in pretty/manifest, placeholder marker in prose/print)
with TODO comments naming the deferred sub-iters (22b.2 typecheck,
22b.3 codegen, 22b.4 prose-projection arms).
Closes a design hole shipped in 20d: the merge-prose prompt instructed
the LLM to emit JSON-AST and gave a 12-line schema-essentials reminder.
JSON-AST is the canonical hashable artefact, not a writing surface; the
reminder was not a language spec. Foreign LLMs had no realistic shot.
20f makes two coupled changes:
1) The LLM now emits Form-A (the canonical authoring surface fixed by
Decision 6). merge-prose loads the original via ailang_core::load_module
and re-renders via ailang_surface::print before embedding (round-trip
is a gating contract on the surface crate, so this is lossless). The
user runs `ail parse foo.new.ailx` to recover JSON, then `ail check`.
2) crates/ailang-core/specs/form_a.md is the complete LLM-targeted
Form-A specification — grammar, every term/pattern/type/def keyword,
schema invariants, pitfall catalogue, four few-shot modules from
examples/*.ailx. Exported as ailang_core::FORM_A_SPEC via include_str!
and embedded verbatim in every merge-prose prompt.
Drift detection in crates/ailang-core/tests/spec_drift.rs: every variant
of Term, Pattern, Type, Def, Literal is reached via exhaustive `match`.
The arms are not the assertion — adding a new variant without updating
the match is a compile error before the test runs. Once matched, an
anchor string is asserted to appear in FORM_A_SPEC. 8 tests, all green.
The hand-written + mechanical-drift-test combo addresses the user's
"distance to code is too big" concern about a docs-only spec. Generator
overkill rejected: structural drift is mechanically caught, but prose
explanation, schema-invariant catalogue, pitfall list, and few-shot
corpus cannot be emitted from AST shape alone.
Tests:
- ailang-core: +8 spec_drift tests; existing 12 unchanged
- ail unit (3): rewritten in lockstep — assert (own T)/(effects IO)
landmarks, FORM-A SPECIFICATION header, FORM_A_SPEC body verbatim
- ail e2e merge_prose_prints_framed_prompt: rewritten — assert
`(module foo` + `FORM-A SPECIFICATION` instead of `ailang/v0`
- Workspace: all green
Richer integration paths (LLM tool-use, MCP server, LSP) were named
in the design discussion and deferred per "kiss". All three layer
additively on the static-prompt path; static prompt remains the
lowest-common-denominator fallback.
Closes the 18-arc's stack-recursion limit. Recursive drop
cascades from 18c.4 overflow on long ADT chains (Linux's 8 MB
default stack maxes out around 1M cells of List). The new
opt-in (drop-iterative) annotation on a Def::Type switches the
synthesised drop_<m>_<T> body from recursive to iterative-with-
explicit-worklist for that type.
Schema:
- TypeDef.drop_iterative: bool. Default false; serde-skip
when false so existing fixtures' canonical JSON hashes stay
stable.
- Form-A: (drop-iterative) clause inside (data T ...).
Worklist runtime (4 new ABI symbols in runtime/rc.c):
- ailang_drop_worklist_new(initial_capacity)
- ailang_drop_worklist_push(wl, ptr)
- ailang_drop_worklist_pop(wl) -> ptr
- ailang_drop_worklist_free(wl)
Heap stretchy buffer, doubling on overflow, null-filtering on
push. Lean 4 / Roc precedent documented in the runtime; the
slot-repurposing strategy was considered and rejected because
not every box has a free pointer-typed slot to thread the
worklist through (Cons head is i64, slot 1 is ptr but it's
the field we're following — no free slot).
Codegen (emit_iterative_drop_fn_for_type): for a
drop_iterative type, drop_<m>_<T>(ptr %p) emits a worklist
loop. Fields of the SAME annotated type push onto the
worklist (mono-typed); fields of DIFFERENT types call their
own drop fn directly (recursive on those, but only if THEY
are themselves recursive — i.e. one level of cascade jump
maximum). Mono-typed-worklist is sound for the deep-self-
recursion case the iter targets (List of List of T just
needs the spine flattened).
Tests:
- examples/rc_drop_iterative_long_list — 1M-cell List of Int
with (drop-iterative) annotation.
- alloc_rc_drop_iterative_handles_million_cell_list E2E —
builds + runs under --alloc=rc, asserts clean exit. With
annotation: exits 0. Without annotation (control): SIGSEGV
at exit code 139 (verified by hand). Worklist is load-
bearing.
- iter18e_drop_iterative_emits_worklist_body_no_self_recursion
IR-shape: worklist body has br to loop_head AND no direct
recursive call into drop_<m>_<T>.
- iter18e_no_annotation_keeps_recursive_drop_body — control:
unannotated variant still emits the 18c.4 recursive shape.
- 3 surface parse-tests for the annotation round-trip.
Test deltas: e2e 58 -> 61 (+3), surface 18 -> 21 (+3). All
other buckets unchanged. cargo test --workspace green.
Known debt (deliberate):
- Mono-typed worklist: cross-type drop-iterative fields call
the other type's drop fn directly. A heterogeneous
worklist would be more general but adds tag tracking
complexity for a case (drop-iterative T containing
drop-iterative T') that's narrower than the deep-self-
recursion target. Documented in
emit_iterative_drop_fn_for_type's doc.
- Closure / Type::Var / Type::Forall fields fall back to
shallow ailang_rc_dec via field_drop_call — same as the
recursive variant.
- Dynamic-tag partial-drop fallback (head_or_zero epilogue
shallow dec when moved_slots non-empty) — out of scope per
brief.
Brummel