Files
AILang/examples/fieldtest/remove-mut_4_bracket_scanner.ail
T
Brummel 5170b6abd1 iter operator-routing-eq-ord.1 (DONE 13/13): drop comparator builtins, route through Eq/Ord
Closes Gitea #1. Realises the "P2 follow-up" called out in
examples/prelude.ail:9 — removes the surface comparator names
`==` / `!=` / `<` / `<=` / `>` / `>=` from the language entirely,
routes the LLM-author's `(app eq …)` / `(app compare …)` /
`(app ne|lt|le|gt|ge …)` through prelude.Eq / prelude.Ord class-
dispatch, ships six named Float-comparison fns
(`float_eq`/`float_ne`/`float_lt`/`float_le`/`float_gt`/`float_ge`)
so Float keeps comparability without an Eq/Ord instance, and emits
primitive instance bodies with `alwaysinline` so the -O0 IR shape
stays at one instruction per comparison.

Plan-task journal (13 tasks, single atomic iter per Approach A):

  Task 1 — Bootstrap: 4 new fixtures (eq_user_adt_smoke.ail,
    eq_float_must_fail.ail, float_compare_smoke.ail,
    operator_unbound_check.ail) + 5 new E2E/pin tests as RED
    starting state. All 5 confirmed RED at start: north-star
    fixed `NoInstance Eq Unit` (preserved by Unit-eq opening line
    intentionally added in plan-self-review); float_compare unknown
    `float_eq`; operator-name typechecked (== still polymorphic);
    must-fail diagnostic lacked `float_eq`; alwaysinline absent
    from IR.

  Task 2 — Codegen alwaysinline + intercept arms: introduced
    `intercept_emit_wants_alwaysinline` allowlist + appended
    ` alwaysinline` between `)` and `{` of the `define` line in
    `emit_fn`; added 9 new intercept arms to
    `try_emit_primitive_instance_body` — `eq__Int`/`eq__Bool`/
    `eq__Unit` + the six `float_*` arms.

  Task 3 — Prelude reshape: `instance Eq Unit` added; Eq Int/Bool
    bodies become placeholder-`false` (intercept overrides); six
    `float_*` free fns added; line-9 P2-follow-up comment removed.
    Lockstep hash re-pins: prelude_module_hash_pin (3abe0d3fa3c11c99
    → new), mono_hash_stability six body-hash literals
    (eq__Int/Bool/Str + compare__Int/Bool/Str all shifted because
    placeholder body changes the canonical hash). IR-snapshot
    regen (hello/list/max3/sum/ws_main) rolled forward into this
    task at orchestrator's pragmatic call — prelude shift forces
    the snapshots immediately.

  Task 4 — Fixture migration: 58 .ail fixtures rewritten
    (`(app == …)` → `(app eq …)`, etc.; Float-typed operand sites
    to `(app float_eq …)` / `(app float_lt …)`). eq_ord_user_adt.ail:21
    inner `==` → `eq` migration with lockstep eq_ord_e2e.rs:134
    body-hash re-pin (3c4cf040cb4e8bb2 → new). Two prose snapshots
    accepted; deps test + 5 hash_pin literals updated as cascading
    consequences.

  Task 5 — Test-scaffold migration: all 8 in-source
    `#[cfg(test)] mod tests` AST-literal sites threaded
    (desugar.rs:2414, check/lib.rs:5656/6092/6220, codegen/lib.rs
    sites). 7 obsolete in-source tests deleted (5 eq_typechecks +
    2 lower_eq ADT/Fn rejection — coverage moves to E2E
    eq_user_adt_smoke + eq_float_must_fail). 2 additional letrec
    tests deleted (single-module check env can't resolve eq/ge
    without prelude auto-import; covered by workspace E2E).

  Task 6 — Lit-pattern desugar: build_eq emits
    `Term::Var { name: "eq" }` instead of `"=="` at desugar.rs:1109;
    doc-comment rewritten to describe class-dispatch.

  Task 7 — Dead-machinery deletion sweep (compile-gated): typchecker
    builtins (install + list comparator entries deleted); codegen
    builtin_binop_typed (10 comparator arms deleted from synth.rs,
    table reduced to arithmetic core); lower_eq fn entirely
    deleted; `==` short-circuit in lower_app deleted;
    `is_static_callee` `==` clause deleted;
    `is_arithmetic_or_comparison_op` renamed to `is_arithmetic_op`
    + caller-update at codegen/lib.rs:2152 + :2529. Dead
    `poly_a_a_to_bool` helpers also removed. Workspace build green
    after compile gate — every caller of the deleted surface was
    migrated by Tasks 4-6.

  Task 8 — Float-aware NoInstance diagnostic: check/lib.rs:856-880
    addendum extended to name `float_eq` / `float_lt` as the
    explicit alternative for Eq/Ord at Float;
    eq_float_noinstance.rs:32-44 assertion extended.

  Task 9 — IR snapshot regen: subsumed by Task 3 (prelude shift
    forced immediate snapshot regen; deferring to Task 9 would
    have left the workspace red between tasks).

  Task 10 — Prose-projection cleanup: 6 comparator arms deleted
    from binop_info; 3 in-source mod-tests updated/deleted
    (comparator-infix rendering would be dishonest now that the
    operators are no longer language identifiers).

  Task 11 — Contract updates: 5 design files rewritten to the
    class-dispatch present —
      float-semantics.md (arithmetic guarantees retained on
        +/-/*/; comparison guarantees transferred from ==/!=/<
        to float_eq/float_ne/float_lt/etc.);
      prelude-classes.md (Eq Unit added to instance list;
        new paragraph on six float_* fns; Float-no-Eq/Ord clause
        gains `→ use float_eq` cross-reference);
      str-abi.md (clause "REMAIN primitive operators" rewritten
        to describe class-method dispatch);
      scope-boundaries.md (multiple operator-name and
        Pattern::Lit-desugar clauses rewritten);
      authoring-surface.md (==, <= dropped from operator-example
        list).

  Task 12 — Initial acceptance gate: workspace 638/0 GREEN;
    bench/compile_check + cross_lang 0 regressed; bench/check.py
    flagged 4 regressions on bench_closure_chain (+29% bump_s,
    +47% rc_s, +29% bump_rss_kb, +48% rc_rss_kb). Orchestrator
    initially classified as DONE-with-concerns; Boss reclassified
    as PARTIAL-via-acceptance-#8-fail after independent re-run,
    extended iter scope to Task 13.

  Task 13 — Direct icmp intercept arms (Boss-extension):
    try_emit_primitive_instance_body gains direct-icmp arms for
    lt__Int / le__Int / gt__Int / ge__Int / ne__Int, bypassing
    the compare__Int → Ordering → match indirection that allocated
    one Ordering ctor per call in tight loops. Each new arm
    inherits `alwaysinline` via the existing allowlist (extended
    accordingly). New IR pin test `ord_int_intercept_ir_pin.rs`
    + smoke fixture `ord_int_intercept_smoke.ail` ratify the
    optimization — opt -O2 -S confirms zero `call
    @ail_prelude_lt__Int` in optimized IR; the icmp folds directly
    at every use site. Bool variants (lt__Bool/etc.) deliberately
    NOT added — no bench/example calls Ord at Bool; spec-extension
    permits skipping if unreachable at bench level. Family can be
    extended symmetrically when first Bool-ordered perf workload
    appears.

Bench-gate post-Task-13: bench_closure_chain bump_s -6.05%,
rc_s -2.67%, bump_rss_kb -0.77%, rc_rss_kb +0.46% — all four
previously-regressed metrics back inside tolerance. Full bench
corpus: 36 metrics, 0 regressed, 0 improved beyond tolerance,
36 stable. bench/check.py exit 0 ✓; bench/compile_check.py exit
0 ✓; bench/cross_lang.py exit 0 ✓.

Workspace: 640 passed, 0 failed across all binaries (delta vs.
milestone start: +5 new E2E/pin tests added in Task 1 + 1 IR pin
added in Task 13 − 9 in-source mod tests deleted as obsolete net
≈ −3). The eq_user_adt_smoke fixture's Unit-opening line was
the deliberate RED-first device added in planner self-review so
the north-star wouldn't accidentally GREEN at start (user-ADT-Eq
on Point with hand-written instance was already operable today;
the milestone's actual delivery is operator-name death + Eq Unit
+ Float-named-fns + cleanup of the two-pathy primitive
comparator machinery).

Net delta: 96 files changed, 1760 insertions, 1101 deletions;
12 net-new files (6 new fixtures, 5 new E2E/pin tests, 1 stats
file). main passes-test-count: 640 (was 633 pre-iter, accounting
for the deletions).

Spec-vs-acceptance addendum: spec §Testing strategy anticipated
the bench-gate-regression case with two recovery paths
(`alwaysinline` investigation or "spec needs revisiting toward α").
Task 13 is the third path — direct intercept arms for `lt`/etc.
that bypass the compare→match path entirely. The spec's contingency
clause was thus generous enough to absorb Task 13 without spec
revision, but a future iter that hits a class-method primitive
where the body shape introduces a similar codegen cost (Ordering
allocation, RC tax, deferred-init) should expect a parallel
extension. The pattern is "primitive instance whose canonical body
indirects through other class methods that allocate" → add a
direct-emit intercept arm + alwaysinline + IR-shape pin.

Concerns absorbed:
  - Codegen lower_app / resolve_top_level_fn gained a
    prelude-fallback lookup so bare monomorphic prelude fns
    (`float_eq` etc.) resolve from non-prelude modules without
    explicit `prelude.float_eq` qualifier. Mirrors the
    typechecker's implicit prelude import — not in plan but
    necessary infra for the named-fn surface to be callable.
  - Recon's "≈10 fixtures" estimate was 6× too low — 58 actual.
    Mechanical migration; no design impact.
  - Recon caught 4 in-source AST-literal sites the spec missed
    (lib.rs:5656 `>=` site + three codegen/lib.rs sites);
    Task 5 covered all.
  - Recon caught 2 contract files outside the spec's update set
    that directly contradicted the milestone (str-abi.md +
    scope-boundaries.md "REMAIN primitive operators" /
    "Pattern::Lit desugar to ==" clauses); Task 11 covered all 5.

Stats file:
`bench/orchestrator-stats/2026-05-21-iter-operator-routing-eq-ord.1.json`.

closes #1
2026-05-21 01:16:21 +02:00

84 lines
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Plaintext

; Axis: a small streaming-feel state machine threading MORE THAN
; ONE piece of state, updating only a SUBSET per branch.
;
; Scan a token stream (a recursive Int list; 1 = '(', 2 = ')',
; 0 = any other token) and decide if the brackets are balanced.
;
; Imperative instinct (exactly what `mut` would invite):
; depth = 0
; ok = true
; for t in stream:
; if t == 1: depth = depth + 1 ; only depth changes
; elif t == 2:
; if depth == 0: ok = false ; only ok changes
; else: depth = depth - 1 ; only depth changes
; ; t == 0 -> neither changes
; return ok && depth == 0
;
; Surviving-surface shape: a recursive scanner fn threading
; (rest, depth, ok) — `loop`/`recur` cannot walk an ADT (it rebinds
; positionally, there is no structural pattern in a recur), so the
; stream traversal is ordinary tail recursion; the per-branch
; "update a subset of the state" becomes "pass the unchanged values
; through unchanged". This is the task that most stresses the
; removal: an imperative author updates one variable and leaves the
; others implicitly alone; here every recur must restate all three.
;
; balanced "(()())" -> true ; stream 1 1 2 1 2 2
; balanced ")(" -> false ; stream 2 1
; Expected stdout (per line): true, false
(module remove-mut_4_bracket_scanner
(data TokStream
(doc "1='(' , 2=')' , 0=other.")
(ctor Nil)
(ctor Cons (con Int) (con TokStream)))
(fn scan
(doc "Thread (rest, depth, ok). Each arm updates a subset of state; the unchanged components must be restated in every tail call.")
(type
(fn-type
(params (own (con TokStream)) (con Int) (con Bool))
(ret (con Bool))))
(params rest depth ok)
(body
(match rest
(case (pat-ctor Nil)
(if ok (app eq depth 0) false))
(case (pat-ctor Cons t more)
(match t
(case (pat-lit 1)
(tail-app scan more (app + depth 1) ok))
(case (pat-lit 2)
(if (app eq depth 0)
(tail-app scan more depth false)
(tail-app scan more (app - depth 1) ok)))
(case _
(tail-app scan more depth ok)))))))
(fn balanced
(type (fn-type (params (own (con TokStream))) (ret (con Bool))))
(params s)
(body (app scan s 0 true)))
(fn main
(type (fn-type (params) (ret (con Unit)) (effects IO)))
(params)
(body
(seq
(app print
(app balanced
(term-ctor TokStream Cons 1
(term-ctor TokStream Cons 1
(term-ctor TokStream Cons 2
(term-ctor TokStream Cons 1
(term-ctor TokStream Cons 2
(term-ctor TokStream Cons 2
(term-ctor TokStream Nil)))))))))
(app print
(app balanced
(term-ctor TokStream Cons 2
(term-ctor TokStream Cons 1
(term-ctor TokStream Nil)))))))))