spec: raw-buf — re-carve .3/.4/.5, type-scoped polymorphic intrinsic prep (refs #7)

Second re-carve. Planning raw-buf.3 (via plan-recon) surfaced that
RawBuf's ops are a THIRD intrinsic shape the intrinsic-bodies mechanism
never handled: type-scoped polymorphic top-level intrinsics (forall a,
param-in {Int,Float,Bool}, called as RawBuf.get). The existing bijection
+ symbol story covers only monomorphic top-level intrinsics (answer,
float_*) and per-type class-method instances (eq__Int).

The gap (both confirmed in source by recon + grounding-check):
- mono_symbol_n mints <base>__<T> from the bare fn name, so RawBuf.get
  @ Int → get__Int — the RawBuf scope never enters the symbol;
  new/get/set/size @ Int would collide with any other poly free fn of
  those (very common) names.
- the bijection collector's Def::Fn arm records the bare name "get" as
  one marker, matching neither the per-type entries nor their symbols;
  one polymorphic marker must map to N per-element entries, which the
  1-marker-to-1-entry bijection cannot express.

So raw-buf.3 is no longer "add 12 table rows" — it is a new language
mechanism. Re-carve (3 remaining iterations):
  raw-buf.3 — type-scoped polymorphic intrinsic mechanism: scope-
              qualified mono symbols (RawBuf_get__Int) + bijection-
              collector expansion over param-in. Built and ratified
              standalone on the stub (a StubT.peek op + its 2 scoped
              entries + mono/bijection unit tests), the prep pattern
              prep.1/.2/.3 used. No RawBuf, no Term::New dependency.
  raw-buf.4 — RawBuf payload (module + 12 scoped entries + drop) +
              Term::New desugar ((new RawBuf ...) sugar, removes both
              deferral arms). Pure consumer of .3. Worked program → 60.
  raw-buf.5 — kernel_stub retirement (peek + answer + stub leave;
              RawBuf carries all roles).

Decided design (Option A): scope-qualified symbols, not bare. Rationale
is semantic — the type-scoped call convention RawBuf.get should carry
through to a collision-free, IR-legible symbol; bare get__Int is a
latent collision landmine on the most-reused op names. Removing that
collision class is itself feature-acceptance criterion-3 evidence.

The raw_buf module Form-A in § Concrete code shapes is gate-verified
(ail check → ok, 35 symbols / 3 modules). Grounding-check PASS: all 10
current-behaviour assumptions ratified by named green tests; the
Term::New codegen-deferral (lib.rs ~2096 + ~3298) is the same
about-to-be-deleted prep.2 transient, reported-not-blocked (consistent
with the override logged on 3ec406e).
This commit is contained in:
2026-05-29 19:10:19 +02:00
parent fbdbe740e6
commit d2885c7ae6
+349 -303
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@@ -1,35 +1,49 @@
# raw-buf — Design Spec
**Date:** 2026-05-29 (revised 2026-05-29)
**Date:** 2026-05-29 (revised twice 2026-05-29)
**Status:** Draft — awaiting user spec review
**Authors:** orchestrator + Claude
> **Revision note.** raw-buf.1 (intercept registry) shipped
> (`140a0c0`). This spec was then re-carved because the
> `intrinsic-bodies` milestone (#9) landed afterwards and removed
> the foundation the original raw-buf.2/.3 split stood on:
> **Revision 1 note (post intrinsic-bodies).** raw-buf.1 (intercept
> registry) shipped (`140a0c0`). The `intrinsic-bodies` milestone
> (#9) then landed and removed the placeholder-body convention the
> original spec relied on — kernel-tier fn bodies are now
> typechecked, so `RawBuf.get` cannot ship a type-lying placeholder
> body; it must be `(intrinsic)`. And an `(intrinsic)` marker now
> requires a matching `INTERCEPTS` entry as a lockstep pair, so a
> "manifest-only / codegen-deferred" intermediate state is
> forbidden. The kernel-manifest and codegen therefore land
> together.
>
> 1. The **placeholder-body convention** the original spec relied
> on (`(body x)` round-trip stubs, "the existing convention from
> `examples/prelude.ail`") no longer exists. `prelude.ail` now
> uses `(intrinsic)` markers, and the checker (`check_fn`,
> `crates/ailang-check/src/lib.rs:2173`) typechecks every
> non-intrinsic body — including kernel-tier bodies. A
> placeholder body for `RawBuf.get` (declared `(ret a)`, body
> constructing a `RawBuf`) is now a hard type error. `get` (and
> `new`/`set`/`size`) MUST be `(intrinsic)`.
> 2. An `(intrinsic)` marker now requires a matching `INTERCEPTS`
> codegen entry as a **lockstep pair**, enforced by
> `intercepts::tests::intercepts_bijection_with_intrinsic_markers`.
> The "manifest visible, codegen deferred" intermediate state
> the original raw-buf.2 was designed to ship is therefore
> forbidden by an invariant. The marker and its codegen entry
> must land in the same iteration.
> **Revision 2 note (post raw-buf.2 + plan-recon).** raw-buf.2 (the
> family-crate rename) shipped (`fbdbe74`). Planning raw-buf.3 then
> surfaced a deeper gap: RawBuf's operations are a *third* intrinsic
> shape the `intrinsic-bodies` mechanism never handled. The bijection
> + symbol story was built for (a) monomorphic top-level intrinsics
> (`answer`, `float_*`) and (b) per-type class-method instances
> (`eq__Int`). RawBuf's ops are **type-scoped polymorphic top-level
> intrinsics** (`forall a` with `param-in {Int,Float,Bool}`, called
> as `RawBuf.get`). For that shape:
>
> Consequence: the kernel-manifest and the codegen now land
> together in one iteration. The remaining work is re-carved into
> three iterations (raw-buf.2/.3/.4) below. The Goal, slab layout,
> and feature-acceptance argument are unchanged.
> 1. `mono_symbol_n` mints `<base>__<T>` from the bare fn name, so
> `RawBuf.get` @ Int becomes `get__Int` — the `RawBuf` scope never
> enters the symbol. `new`/`get`/`set`/`size` @ Int would collide
> with any other polymorphic free fn of those (very common) names.
> 2. The bijection collector's `Def::Fn` arm records the bare name
> `"get"` as one marker — matching neither the per-type entries nor
> their symbols. One polymorphic marker must map to N per-element
> entries, which the current 1-marker-to-1-entry bijection cannot
> express.
>
> So raw-buf.3 is no longer "add 12 table rows" — it is a new
> language mechanism (type-scoped polymorphic intrinsics) that RawBuf
> is the first consumer of. The remaining work is re-carved into a
> mechanism prep (raw-buf.3), the RawBuf payload (raw-buf.4), and the
> stub retirement (raw-buf.5). The decided naming scheme is
> scope-qualified mono symbols (`RawBuf_get__Int`); the mechanism is
> ratified standalone on the stub (the prep pattern that prep.1/.2/.3
> used) before RawBuf consumes it. The Goal, slab layout, and
> feature-acceptance argument are unchanged.
## Goal
@@ -52,116 +66,140 @@ The milestone also fulfils the architectural commitment from the
kernel-extensions whitepaper § "Plugin contract": the migration
of the hardcoded primitive-instance intercepts into one registry,
triggered by the first real base extension shipping. raw-buf.1
already discharged that migration (the registry is live and the
`intrinsic-bodies` bijection pin locks marker ↔ entry); RawBuf is
now the first *real-payload* consumer of that registry.
This makes raw-buf both a feature ship (a new type LLM authors
can reach for) and the proof that the registry path carries a
genuine domain type, not just the migrated primitive intercepts.
already discharged that migration; RawBuf is now the first
*real-payload* consumer of that registry — and the first consumer
of the type-scoped polymorphic intrinsic mechanism raw-buf.3 adds.
## Architecture
Four iterations. raw-buf.1 is done; .2/.3/.4 remain.
Five iterations. raw-buf.1 and raw-buf.2 are done; .3/.4/.5 remain.
1. **Intercept registry** (raw-buf.1) — **DONE** (`140a0c0`).
Lifted the hard-coded `try_emit_primitive_instance_body` match
into the registry table `INTERCEPTS` in
`crates/ailang-codegen/src/intercepts.rs`; the dispatch site is
a `intercepts::lookup` call. Pure refactor, zero behavioural
change. (The subsequent `intrinsic-bodies` milestone added the
`(intrinsic)` marker, the `Term::Intrinsic` leaf, and the
marker ↔ entry bijection pin on top of this registry.)
an `intercepts::lookup` call. (The subsequent `intrinsic-bodies`
milestone added the `(intrinsic)` marker, the `Term::Intrinsic`
leaf, and the marker ↔ entry bijection pin on top of it.)
2. **Kernel family-crate rename** (raw-buf.2) — Pure refactor,
zero behavioural change. Rename `crates/ailang-kernel-stub/`
`crates/ailang-kernel/` and reshape it as a *family-crate*: one
Cargo crate hosting all kernel-tier modules as sibling Rust
submodules under `src/`, one submodule per `.ail` source. The
renamed crate carries `src/kernel_stub/{mod.rs, source.ail}`
(the existing stub, **verbatim including its current `answer`
intrinsic fn** — the source has grown since the original spec
was written). `src/lib.rs` re-exports each submodule's `SOURCE`
const under the stable name every consumer already binds
(`pub use kernel_stub::SOURCE as STUB_AIL;`). The acyclic chain
`ailang-surface → ailang-kernel → ailang-core` is preserved;
the parse hop `parse_kernel_stub` stays in `ailang-surface`. No
`raw_buf` submodule yet — this iteration is *only* the rename,
so its failure mode is "existing tests break", the cleanest
bisection target. Ratified by the existing suite green.
2. **Kernel family-crate rename** (raw-buf.2) — **DONE**
(`fbdbe74`). Renamed `crates/ailang-kernel-stub/`
`crates/ailang-kernel/`, reshaped as a family-crate
(`src/lib.rs` hub re-exporting `src/kernel_stub/{mod.rs,
source.ail}`). Public symbol `STUB_AIL` preserved; zero
behavioural change.
3. **RawBuf end-to-end** (raw-buf.3) — The feature ship, landing
the manifest and the codegen together (the lockstep pair the
bijection invariant requires). Adds:
3. **Type-scoped polymorphic intrinsic mechanism** (raw-buf.3) —
The new language mechanism RawBuf needs, built and ratified
standalone on the stub (no RawBuf yet), mirroring how prep.1/.2/.3
built kernel-extension mechanisms ratified by the stub. Two
coupled pieces:
- **Scope-qualified mono symbols.** When a type-scoped call
`T.f` (prep.1 spelling) resolves to a polymorphic op `f` of
TypeDef `T`, monomorphisation mints `T_f__<elem>` (e.g.
`StubT_peek__Int`) — the TypeDef scope is part of the symbol,
so two different types' identically-named ops never collide,
and the emitted IR is legible (it reads as "the `T.f`
specialised to `<elem>`"). The codegen intercept dispatch keys
on this scoped symbol.
- **Bijection expansion over `param-in`.** The bijection
collector (`intercepts::tests::workspace_intrinsic_markers`)
gains an arm: a top-level `(intrinsic)` op that is polymorphic
and type-scoped to a TypeDef with `param-in (a S1 S2 …)`
expands to one marker `T_f__Si` per allowed element type `Si`.
One polymorphic marker → N per-element entries, all pinned by
`intercepts_bijection_with_intrinsic_markers`.
Ratified by adding ONE polymorphic type-scoped `(intrinsic)` op
to the stub's `StubT` (`StubT.peek : (borrow (StubT a)) -> a`)
plus its 2 scope-qualified `INTERCEPTS` entries
(`StubT_peek__Int`, `StubT_peek__Float` — StubT's `param-in` is
`{Int, Float}`) and a unit test asserting the scoped symbols +
the bijection. `peek` retires with the stub in raw-buf.5, exactly
as `answer` does. No running E2E here (constructing a `StubT`
needs the Term::New desugar that lands in raw-buf.4); the
mechanism is unit-test ratified.
4. **RawBuf payload + Term::New desugar** (raw-buf.4) — RawBuf as a
clean consumer of the raw-buf.3 mechanism, plus the `(new …)`
construction sugar. Adds:
- The `raw_buf` submodule (`src/raw_buf/{mod.rs, source.ail}`)
with the `RawBuf` TypeDef (`param-in (a Int Float Bool)`) and
the four operations `new`/`get`/`set`/`size`, each an
`(intrinsic)` marker (NOT a placeholder body).
- The 12 element-specialised `INTERCEPTS` entries (4 ops × 3
element types) lowering each via `@ailang_rc_alloc` +
getelementptr + load/store — no new C code. The entry `name`
of each MUST equal the mono-mangled symbol of its
`(intrinsic)` marker; the bijection test is the pin that
forces this and surfaces the exact expected strings.
- A desugar pass `(new T <types…> <values…>)` → an instantiated
`(app T.new <values…>)` that consumes the `NewArg::Type`
element type to drive monomorphisation to `new__RawBuf__<T>`,
so `Term::New` is eliminated before codegen. `Term::New`
becomes a checker-side-only construct (the codegen completion
the prep.2 deferral pointed at). raw-buf.3 removes **both**
`Term::New` deferral arms codegen currently carries — the
`lower_term` arm (`crates/ailang-codegen/src/lib.rs:2094`,
"milestone raw-buf" internal error) and the sibling
synth-path arm (`lib.rs:3296`). These arms are the deferral
marker prep.2 left; raw-buf.3 discharges them. They are not a
relied-upon current invariant — the milestone's correctness
depends on *removing* them, not on their persisting.
the four ops `new`/`get`/`set`/`size`, each an `(intrinsic)`
marker.
- The 12 scope-qualified `INTERCEPTS` entries
(`RawBuf_{new,get,set,size}__{Int,Float,Bool}`) + emit fns
(`@ailang_rc_alloc` + getelementptr + load/store)mechanical
now that raw-buf.3 built the naming + bijection machinery.
- The `Term::New` desugar `(new T <types…> <values…>)`
`(app T.new <values…>)` (general — `(new StubT 42)` benefits
too), removing BOTH codegen `Term::New` deferral arms
(`crates/ailang-codegen/src/lib.rs` ~2094 `lower_term` +
~3296 synth path) that prep.2 left marked "milestone raw-buf".
- Drop for primitive-element RawBuf: a single
`@ailang_rc_release` on the slab pointer (no element-walking;
elements are primitives).
- `ailang-surface` wiring: `parse_raw_buf` + the workspace
injection that makes `raw_buf` a kernel-tier auto-imported
module (workspace module count 4 → 5).
`@ailang_rc_release` on the slab pointer.
- `ailang-surface` wiring: `parse_raw_buf` + workspace injection
(raw_buf kernel-tier auto-imported; workspace count 4 → 5).
The worked consumer program runs end-to-end and prints `60`.
`kernel_stub` stays alongside this iteration (count 5).
`kernel_stub` (with `peek` + `answer`) stays alongside (count 5).
4. **kernel_stub retirement** (raw-buf.4) — Focused removal.
RawBuf now subsumes every ratification role kernel_stub held:
`Term::New` end-to-end (the `(new RawBuf …)` consumer),
`param-in` reject (the Str-element reject fixture), kernel-tier
auto-import (RawBuf visible without `(import raw_buf)`), and the
`(intrinsic)` mechanism (RawBuf's four ops + their registry
entries). The stub is therefore pure redundancy. Delete
`src/kernel_stub/` + its re-export, drop `parse_kernel_stub` and
its surface injection, remove the `answer` `INTERCEPTS` entry +
`emit_answer` (its `(intrinsic)` marker leaves with the stub —
the bijection lockstep holds), delete the
`kernel_stub_module_round_trips` test, re-baseline `workspace_pin`
to 4 (raw_buf in, kernel_stub out — net unchanged), and update
5. **kernel_stub retirement** (raw-buf.5) — RawBuf now subsumes
every ratification role the stub held: `Term::New` end-to-end
(the `(new RawBuf …)` consumer), `param-in` reject (the Str
reject fixture), kernel-tier auto-import, the monomorphic
intrinsic path (RawBuf has no nullary intrinsic, but the path is
exercised by the prelude's `float_*`), and — crucially — the
type-scoped polymorphic intrinsic mechanism (RawBuf's four ops).
Delete `src/kernel_stub/` + its re-export, drop
`parse_kernel_stub` + its injection, remove the `answer` and the
two `StubT_peek__*` `INTERCEPTS` entries + their emit fns (their
markers leave with the stub — the bijection lockstep holds),
delete `kernel_stub_module_round_trips`, re-baseline
`workspace_pin` to 4 (raw_buf in, kernel_stub out), and update
`design/INDEX.md` + `design/models/0007-kernel-extensions.md`.
The `ailang-kernel` crate itself stays as the family-crate home
for future kernel-tier modules (series, matrix, …). Isolating
the retirement keeps each bijection-registry change (12 entries
added in .3, the `answer` entry removed in .4) in its own diff.
The `ailang-kernel` crate stays as the family-crate home for
future kernel-tier modules.
The ordering rationale: .2 is the only zero-behavioural-change
iteration (rename), the cleanest bisection target; .3 lands the
feature on a registry that has already absorbed every legacy
intercept (raw-buf.1) and on the renamed family-crate (raw-buf.2),
so the RawBuf manifest+codegen do not co-mingle with a registry
move or a crate move; .4 removes the now-redundant stub without
touching the new RawBuf code.
Ordering rationale: .3 isolates the risky mono+bijection mechanism
change (proven on the stub) from RawBuf's payload diff; .4 lands
RawBuf as a mechanical consumer plus the orthogonal `(new …)`
desugar; .5 removes the now-redundant stub without touching the new
RawBuf code. Each bijection-registry change is isolated to one diff
(peek entries added in .3, 12 RawBuf entries in .4, peek+answer
removed in .5).
## Concrete code shapes
### Primary — the raw_buf kernel-tier module (raw-buf.3, gate-verified)
### Primary — the raw-buf.3 mechanism ratifier (StubT.peek)
This is the exact Form-A source the `raw_buf` submodule embeds. It
parses and type-checks against the current tool (`ail check`
`ok`); the four `(intrinsic)` markers are legal because the module
is `(kernel)`. The element type is restricted to `{Int, Float,
Bool}` via `param-in`. `RawBuf.get` returns the bare element type
`a`; `set` is linear (`own` in, `own` out).
raw-buf.3 adds one polymorphic type-scoped `(intrinsic)` op to the
stub to prove the mechanism. The op and its scope-qualified entries
are the iteration's concrete deliverable (the must-pass evidence
that scoped symbols + bijection expansion work). The fn is appended
to the existing `STUB_AIL` source (`crates/ailang-kernel/src/kernel_stub/source.ail`):
```text
(fn peek
(doc "Ratifies the type-scoped polymorphic intrinsic mechanism: StubT.peek is polymorphic over a (param-in {Int,Float}) and type-scoped to StubT. Codegen intercepts StubT_peek__Int / StubT_peek__Float emit a load from the Stub payload. Retires with the stub in raw-buf.5.")
(type (forall (vars a) (fn-type (params (borrow (con StubT a))) (ret a))))
(params s)
(intrinsic))
```
(Shown `text`, not `ail`: `kernel_stub` is a reserved built-in
module name, so the source cannot be `ail check`-ed standalone —
`reserved-module-name`. Ratification is the round-trip test + the
bijection/mono unit tests, not a standalone parse.) Its two
scope-qualified entries (`StubT_peek__Int`, `StubT_peek__Float`)
land in `INTERCEPTS` together with the bijection-collector
extension; the bijection test pins the 1-marker→2-entries mapping.
### Primary — the raw_buf kernel-tier module (raw-buf.4, gate-verified)
The exact Form-A source the `raw_buf` submodule embeds. It parses
and type-checks against the current tool (`ail check``ok`); the
four `(intrinsic)` markers are legal because the module is
`(kernel)`. `RawBuf.get` returns the bare element type `a`; `set`
is linear (`own` in, `own` out).
```ail
(module raw_buf
@@ -171,22 +209,22 @@ Bool}` via `param-in`. `RawBuf.get` returns the bare element type
(ctor B a)
(param-in (a Int Float Bool)))
(fn new
(doc "Allocate an uninitialised RawBuf of capacity n. Compiler-supplied (intrinsic) body; codegen intercept new__RawBuf__<T> emits @ailang_rc_alloc plus the i64 size header. Element bytes are uninitialised; caller must set before get.")
(doc "Allocate an uninitialised RawBuf of capacity n. Compiler-supplied (intrinsic) body; codegen intercept RawBuf_new__<T> emits @ailang_rc_alloc plus the i64 size header. Element bytes are uninitialised; caller must set before get.")
(type (forall (vars a) (fn-type (params (con Int)) (ret (own (con RawBuf a))))))
(params n)
(intrinsic))
(fn get
(doc "Indexed read. UB if i >= (size b); caller checks bounds via size. Compiler-supplied (intrinsic) body; codegen intercept emits getelementptr plus load.")
(doc "Indexed read. UB if i >= (size b); caller checks bounds via size. Compiler-supplied (intrinsic) body; codegen intercept RawBuf_get__<T> emits getelementptr plus load.")
(type (forall (vars a) (fn-type (params (borrow (con RawBuf a)) (con Int)) (ret a))))
(params b i)
(intrinsic))
(fn set
(doc "Indexed write. Linear: own in, own out. Under uniqueness in-place; under shared copy-on-write (Issue #22). Compiler-supplied (intrinsic) body; codegen intercept emits getelementptr plus store.")
(doc "Indexed write. Linear: own in, own out. Under uniqueness in-place; under shared copy-on-write (Issue #22). Compiler-supplied (intrinsic) body; codegen intercept RawBuf_set__<T> emits getelementptr plus store.")
(type (forall (vars a) (fn-type (params (own (con RawBuf a)) (con Int) a) (ret (own (con RawBuf a))))))
(params b i v)
(intrinsic))
(fn size
(doc "Element count. Compiler-supplied (intrinsic) body; codegen intercept emits a single i64 load from the slab header.")
(doc "Element count. Compiler-supplied (intrinsic) body; codegen intercept RawBuf_size__<T> emits a single i64 load from the slab header.")
(type (forall (vars a) (fn-type (params (borrow (con RawBuf a))) (ret (con Int)))))
(params b)
(intrinsic)))
@@ -196,20 +234,18 @@ The `(ctor B a)` is a nominal fiction for the type system: it
gives `RawBuf` an identity and keeps `a` non-phantom. Real code
never constructs it — every operation is codegen-intercepted, and
`(new RawBuf …)` desugars to `(app RawBuf.new …)`, not to a
`(term-ctor RawBuf B …)`. The four `(intrinsic)` markers carry no
runnable body; codegen supplies the implementation via the
registry (raw-buf.3).
`(term-ctor RawBuf B …)`.
### Primary — the worked consumer program (raw-buf.3 acceptance)
### Primary — the worked consumer program (raw-buf.4 acceptance)
This is the program an LLM author naturally writes for "I need a
small mutable indexed buffer to score N values and read them
back." It is the feature-acceptance criterion's empirical
evidence. It references the `raw_buf` module, which is only
injected once raw-buf.3 wires it through `ailang-surface` — so it
does **not** check against the current tool (RawBuf is not yet a
workspace module). Left unlabeled deliberately: it describes
post-raw-buf.3 surface, not current behaviour.
The program an LLM author naturally writes for "I need a small
mutable indexed buffer to score N values and read them back." It is
the feature-acceptance criterion's empirical evidence. It uses the
`(new RawBuf …)` construction sugar (available once raw-buf.4 lands
the Term::New desugar). It references the `raw_buf` module, injected
only from raw-buf.4 — so it does **not** check against the current
tool (RawBuf is not yet a workspace module). Left unlabeled
deliberately: it describes post-raw-buf.4 surface.
```
(module raw_buf_demo
@@ -227,13 +263,18 @@ post-raw-buf.3 surface, not current behaviour.
; ail check && ail build && ail run → prints 60
```
No `(import raw_buf)` needed: `RawBuf` is visible via the
kernel-tier auto-import path (prep.3). `RawBuf.set` / `.get`
resolve via type-scoped namespacing (prep.1). `(new RawBuf (con
Int) 3)` is a `Term::New` whose `NewArg::Type` is `(con Int)`; the
raw-buf.3 desugar threads that into `new__RawBuf__Int`.
No `(import raw_buf)` needed: `RawBuf` is visible via kernel-tier
auto-import (prep.3). `RawBuf.set`/`.get`/`.new` resolve via
type-scoped namespacing (prep.1) and mono to the scope-qualified
symbols `RawBuf_set__Int` / `RawBuf_get__Int` / `RawBuf_new__Int`.
The element type `a = Int` is fixed by inference: it flows from the
`(app RawBuf.set buf 0 10)` value arg (`10 : Int`) through the
linear `own (RawBuf a)` threading. (For the direct-call equivalent
without the `(new …)` sugar — `(let buf (app RawBuf.new 3) …)`
the same inference applies; the desugar reduces `(new RawBuf (con
Int) 3)` to exactly that.)
### Primary — the param-in reject fixture (raw-buf.3 must-fail)
### Primary — the param-in reject fixture (raw-buf.4 must-fail)
```
(module raw_buf_reject_str
@@ -245,61 +286,78 @@ raw-buf.3 desugar threads that into `new__RawBuf__Int`.
```
Must fail at the checker with the `ParamNotInRestrictedSet`
diagnostic shipped in prep.3 (fieldtest F8). It is the must-fail
evidence that the `param-in` restriction is alive on a
real-payload extension, not just the prep.3 `StubT` fixture. Like
the worked program, it depends on `raw_buf` being injected, so it
is not gate-checkable against the current tool (unlabeled).
diagnostic shipped in prep.3 (fieldtest F8) the must-fail evidence
that `param-in` is alive on a real-payload extension. Depends on
`raw_buf` being injected, so not gate-checkable today (unlabeled).
### Secondary — INTERCEPTS entry shape (raw-buf.3, implementation)
### Secondary — scope-qualified mono symbol (raw-buf.3, implementation)
The real registry struct (raw-buf.1) is `Intercept { name,
expected_params, expected_ret, wants_alwaysinline, emit }`. The 12
RawBuf entries follow the existing rows' shape. One representative
(the exact symbol strings are derived by the implementer from the
bijection test, which mangles each `(intrinsic)` marker and
reports the expected name):
Current behaviour: `mono_symbol_n(base, types)`
(`crates/ailang-check/src/mono.rs:521`) joins `base` and each
type's mono suffix with `__`. For a bare-named poly free fn `get`
it yields `get__Int` — no type scope. The bijection collector's
`Def::Fn` arm (`intercepts.rs` ~490) inserts the bare `f.name`.
raw-buf.3 change (shape — exact threading mapped by plan-recon):
a type-scoped call `T.f` carries the resolved TypeDef `T`; mono
uses a scope-qualified base `T_f` so the symbol is `T_f__<elem>`
(`StubT_peek__Int`, later `RawBuf_get__Int`). The bijection
collector gains an arm that, for a polymorphic top-level
`(intrinsic)` op scoped to a TypeDef with `param-in (a S1 …)`,
emits `T_f__Si` for each `Si`. Both the mono mint and the collector
must compute the identical string (the bijection test is the pin).
### Secondary — INTERCEPTS entry shape (raw-buf.4, implementation)
The registry struct (raw-buf.1) is `Intercept { name,
expected_params, expected_ret, wants_alwaysinline, emit }`. One
representative of the 12 RawBuf entries (the exact symbol strings
are produced by the raw-buf.3 mechanism and pinned by the bijection
test):
```rust
// crates/ailang-codegen/src/intercepts.rs — appended to INTERCEPTS
Intercept {
name: "new__RawBuf__Int", // == mono-mangled name of raw_buf.new @ a=Int
name: "RawBuf_new__Int", // scope-qualified mono symbol of RawBuf.new @ Int
expected_params: &["i64"], // capacity n
expected_ret: "ptr", // slab base pointer
wants_alwaysinline: false,
emit: emit_new_raw_buf_int, // @ailang_rc_alloc(8 + n*8); store i64 n at offset 0
emit: emit_rawbuf_new_int, // @ailang_rc_alloc(8 + n*8); store i64 n at offset 0
},
// + new__RawBuf__{Float,Bool}, RawBuf_get__{Int,Float,Bool},
// + RawBuf_new__{Float,Bool}, RawBuf_get__{Int,Float,Bool},
// RawBuf_set__{Int,Float,Bool}, RawBuf_size__{Int,Float,Bool}
```
### Secondary — Term::New desugar (raw-buf.3, implementation)
### Secondary — Term::New desugar (raw-buf.4, implementation)
`Term::New { type_name, args }` where `args: Vec<NewArg>`
(`NewArg::Type | NewArg::Value`, both already parsed + round-trip
ratified). The new desugar pass rewrites it to an application of
the type's `new` fn, instantiated at the element type carried by
the leading `NewArg::Type`:
`Term::New { type_name, args }` with `args: Vec<NewArg>`
(`NewArg::Type | NewArg::Value`, both parsed + round-trip ratified).
The desugar rewrites it to an application of the type's `new` fn,
passing only the `NewArg::Value` args:
```
(new RawBuf (con Int) 3) ; Term::New { type_name: "RawBuf",
; args: [Type(con Int), Value(3)] }
──desugar──▶
(app RawBuf.new 3) @ a = Int ; instantiation pins mono → new__RawBuf__Int
(app RawBuf.new 3) ; a = Int resolved by inference from use
```
The desugar consumes the `NewArg::Type` for the instantiation and
passes only the `NewArg::Value` args as call arguments. After this
pass no `Term::New` survives into codegen; both deferral arms
(`lib.rs:2094` in `lower_term`, "milestone raw-buf" internal
error, and the sibling at `lib.rs:3296` in the synth path) become
unreachable and are removed. Whether
the prep.2 checker already accepts the `NewArg::Type`-bearing
`Term::New` semantically, or needs a small extension, is a
raw-buf.3 task to verify first (the form parses + round-trips
today; the lift pass passes `NewArg::Type` through untouched).
Important: the AST has no type-ascription term and `Term::App`
carries no type-args, so the desugar **drops** the `NewArg::Type`
and the element type is recovered by ordinary inference (it flows
from how the result is used — see the worked program). This
suffices for every real program that uses the buffer; an isolated
`(new RawBuf (con Int) 3)` with no constraining use would leave `a`
ambiguous, which is acceptable (no real program does that). After
this pass no `Term::New` survives into codegen; both deferral arms
(`lib.rs` ~2094 `lower_term`, ~3296 synth) are removed. The prep.2
checker already accepts `Term::New` (it parses, round-trips, and
typechecks via the `new` def's signature); whether it needs any
extension for the `NewArg::Type`-bearing form is a raw-buf.4
verify-first task (plan-recon maps the current Term::New typecheck
path).
### Secondary — slab layout (raw-buf.3)
### Secondary — slab layout (raw-buf.4)
```
[ size : i64 ][ elem_0 ][ elem_1 ] ... [ elem_{size-1} ]
@@ -307,177 +365,165 @@ today; the lift pass passes `NewArg::Type` through untouched).
offset 0 offset 8 offset 8 + size*sizeof(T)
```
Element widths: `Int = 8`, `Float = 8`, `Bool = 1`. Header is
i64, 8-byte aligned; element payload follows directly.
`@ailang_rc_alloc` is called with `8 + size * sizeof(T)` and
returns the slab base `ptr`. The size header is self-describing,
so drop and `RawBuf.size` need no side-table. Drop is a single
`@ailang_rc_release` on the slab pointer — primitive elements
carry no recursive drops. The per-TypeDef drop generation gets a
"primitive-element-RawBuf" arm dispatched via the same registry.
Element widths: `Int = 8`, `Float = 8`, `Bool = 1`. Header is i64,
8-byte aligned; element payload follows directly. `@ailang_rc_alloc`
is called with `8 + size * sizeof(T)` and returns the slab base
`ptr`. The size header is self-describing, so drop and `RawBuf.size`
need no side-table. Drop is a single `@ailang_rc_release` on the
slab pointer — primitive elements carry no recursive drops; the
per-TypeDef drop generation gets a "primitive-element-RawBuf" arm.
## Components
| Component | Iter | Files |
|-----------|------|-------|
| Intercept registry | raw-buf.1 (DONE) | `crates/ailang-codegen/src/intercepts.rs` + dispatch site in `lib.rs` |
| Kernel family-crate rename | raw-buf.2 | `git mv crates/ailang-kernel-stub crates/ailang-kernel`; reshape to `src/lib.rs` + `src/kernel_stub/{mod.rs, source.ail}` (existing stub source incl. `answer` re-housed verbatim); `Cargo.toml` package + workspace member + dep-alias renames; `crates/ailang-surface/Cargo.toml` dep rename + `loader.rs` use-path renames; `design/INDEX.md` + `CLAUDE.md` code-layout row |
| RawBuf module + codegen + desugar + drop | raw-buf.3 | new `crates/ailang-kernel/src/raw_buf/{mod.rs, source.ail}` + `lib.rs` re-export; `parse_raw_buf` + workspace injection in `crates/ailang-surface/src/loader.rs` + re-export in `lib.rs`; 12 entries + emit fns in `crates/ailang-codegen/src/intercepts.rs`; `Term::New` desugar in `crates/ailang-core/src/desugar.rs` (and removal of the codegen `Term::New` error arm in `crates/ailang-codegen/src/lib.rs`); primitive-element-RawBuf drop arm; `workspace_pin` 4 → 5; round-trip + E2E tests |
| kernel_stub retirement | raw-buf.4 | delete `crates/ailang-kernel/src/kernel_stub/` + its `lib.rs` re-export; drop `parse_kernel_stub` + injection in `ailang-surface`; remove `answer` entry + `emit_answer` in `intercepts.rs`; delete `kernel_stub_module_round_trips` test; `workspace_pin` 54; `design/INDEX.md` + `design/models/0007-kernel-extensions.md` updates |
| Intercept registry | raw-buf.1 (DONE) | `crates/ailang-codegen/src/intercepts.rs` + dispatch in `lib.rs` |
| Kernel family-crate rename | raw-buf.2 (DONE) | `crates/ailang-kernel/` (renamed); `ailang-surface` dep + `loader.rs`; doc/ledger rows |
| Type-scoped polymorphic intrinsic mechanism | raw-buf.3 | scope-qualified mono mangling in `crates/ailang-check/src/mono.rs` (+ wherever prep.1 type-scoped resolution records the TypeDef, per recon); bijection-collector expansion arm in `crates/ailang-codegen/src/intercepts.rs` (`workspace_intrinsic_markers`); `StubT.peek` fn added to `crates/ailang-kernel/src/kernel_stub/source.ail` + 2 `StubT_peek__*` entries + emit fns; `kernel_stub_module_round_trips` updated for the new fn; mono/bijection unit tests |
| RawBuf payload + Term::New desugar | raw-buf.4 | new `crates/ailang-kernel/src/raw_buf/{mod.rs, source.ail}` + `lib.rs` re-export; `parse_raw_buf` + injection in `crates/ailang-surface/src/loader.rs` + re-export in `lib.rs`; 12 entries + emit fns in `intercepts.rs`; `Term::New` desugar in `crates/ailang-core/src/desugar.rs` + removal of both codegen deferral arms in `crates/ailang-codegen/src/lib.rs`; primitive-element-RawBuf drop arm; `workspace_pin` 45; round-trip + E2E tests |
| kernel_stub retirement | raw-buf.5 | delete `crates/ailang-kernel/src/kernel_stub/` + re-export; drop `parse_kernel_stub` + injection; remove `answer` + `StubT_peek__*` entries + emit fns in `intercepts.rs`; delete `kernel_stub_module_round_trips`; `workspace_pin` 5 → 4; `design/INDEX.md` + `design/models/0007-kernel-extensions.md` |
## Data flow
**Build-time** (raw-buf.3 onwards):
**Mechanism (raw-buf.3):**
1. A consumer call `T.f` (type-scoped spelling, prep.1) resolves to
the polymorphic op `f` of TypeDef `T`, recording `T` as the
resolution scope.
2. Monomorphisation at element type `Si` mints the scope-qualified
symbol `T_f__Si`; codegen emits a fn of that name; the intercept
dispatch keys on it.
3. The bijection collector expands each polymorphic type-scoped
`(intrinsic)` op over its TypeDef's `param-in` set into the same
`T_f__Si` strings, and requires each to resolve to an `INTERCEPTS`
entry (and vice versa, minus `OPTIMISATION_ONLY`).
**Build-time (raw-buf.4 onwards):**
1. CLI loads workspace → `ailang-surface` injects `raw_buf` as a
kernel-tier module (`kernel: true`) just like `prelude`.
kernel-tier module (`kernel: true`).
2. `check` walks consumer code; `(con RawBuf (con Int))` resolves
to `raw_buf.RawBuf` via the kernel-tier auto-import path
(prep.3).
3. `param-in` on RawBuf's `a` rejects non-{Int,Float,Bool}
instantiations at the consumer typecheck site, using the
existing `ParamNotInRestrictedSet` diagnostic.
to `raw_buf.RawBuf` via kernel-tier auto-import (prep.3).
3. `param-in` on `a` rejects non-{Int,Float,Bool} instantiations
via the existing `ParamNotInRestrictedSet` diagnostic.
**Codegen-time** (raw-buf.3 onwards):
1. The desugar pass replaces every `Term::New { type_name, args }`
with an instantiated `(app <type_name>.new <values>)`, pinning
the element type from the leading `NewArg::Type`.
2. For each fn, codegen reaches the registry dispatch site. If the
fn's mono name resolves via `intercepts::lookup`, the entry's
`emit` runs; the `(intrinsic)` marker carries no body to fall
back to. Otherwise the normal AILang lowering runs.
3. For RawBuf consumers, `new__RawBuf__Int` emits the alloc;
`RawBuf_set__Int` a `store i64`; `RawBuf_get__Int` a `load
i64`; `RawBuf_size__Int` a single header load.
**Codegen-time (raw-buf.4 onwards):**
1. The desugar replaces every `Term::New` with `(app T.new
<values>)`; the element type is inferred from use.
2. Codegen reaches the registry dispatch site; if the fn's
scope-qualified mono symbol resolves via `intercepts::lookup`,
the entry's `emit` runs (the `(intrinsic)` marker has no body).
3. `RawBuf_new__Int` emits the alloc; `RawBuf_set__Int` a `store
i64`; `RawBuf_get__Int` a `load i64`; `RawBuf_size__Int` a header
load.
**Bijection interaction** (raw-buf.3 / .4):
Each RawBuf `(intrinsic)` marker reachable from the workspace is
collected by `workspace_intrinsic_markers()` and must resolve to
an `INTERCEPTS` entry (and vice versa, minus the
`OPTIMISATION_ONLY` allowlist). raw-buf.3 adds 12 markers + 12
entries together. raw-buf.4 removes the `answer` marker (with the
stub) and the `answer` entry together. A half-landed change on
either side is a hard unit-test failure
(`intercepts_bijection_with_intrinsic_markers`).
**Workspace module count:** prelude + kernel_stub + 2 test
fixtures = 4 today. raw-buf.3 adds raw_buf → 5. raw-buf.4 retires
kernel_stub → 4. The `workspace_pin` test pins each transition.
**Workspace module count:** prelude + kernel_stub + 2 test fixtures
= 4 today. raw-buf.4 adds raw_buf → 5. raw-buf.5 retires kernel_stub
→ 4. The `workspace_pin` test pins each transition.
## Error handling
Two consumer-facing diagnostics; both already shipped, no new arms
needed:
Two consumer-facing diagnostics; both already shipped, no new arms:
- **`param-not-in-restricted-set`** (prep.3, fieldtest F8). Fires
when a consumer writes `(con RawBuf (con Str))` or any
non-{Int,Float,Bool} element. Names the type, the variable, the
TypeDef, and the restricted set.
- **`new-type-not-constructible`** (prep.3, fieldtest F5). Fires
when a consumer writes `(new SomeType …)` and `SomeType` has no
`(fn new …)` in its home module. raw_buf ships `(fn new …)`, so
the worked program passes; the diagnostic still protects future
authors who write `(new Counter 0)` against a `new`-less type.
- **`param-not-in-restricted-set`** (prep.3, fieldtest F8) — fires
on `(con RawBuf (con Str))` or any non-{Int,Float,Bool} element.
- **`new-type-not-constructible`** (prep.3, fieldtest F5) — fires on
`(new SomeType …)` when `SomeType` has no `(fn new …)`. raw_buf
ships `new`, so the worked program passes.
The codegen `Term::New` deferral arms (`lib.rs:2094` in
`lower_term`, message "… milestone raw-buf"; and the sibling at
`lib.rs:3296` in the synth path) are **removed** in raw-buf.3 once
the desugar eliminates `Term::New` before codegen. Neither is a
user-facing diagnostic — both are the deferral marker prep.2 left,
which raw-buf.3 discharges. They have no test pinning them today
(they are an internal `CodegenError::Internal`, not an asserted
behaviour); raw-buf.3's end-to-end build-and-run E2E (the worked
program printing `60`) is the forward ratification — it exercises
the `Term::New` → desugar → codegen path that replaces them.
The codegen `Term::New` deferral arms (`lib.rs` ~2094 + ~3296,
message "… milestone raw-buf") are **removed** in raw-buf.4 once the
desugar eliminates `Term::New` before codegen. Neither is
user-facing — both are the prep.2 deferral marker. They have no test
pinning them today (internal `CodegenError::Internal`); raw-buf.4's
build-and-run E2E (the worked program printing `60`) is the forward
ratification.
Bounds checks are **not** in scope (whitepaper § "RawBuf — the
base extension"): `RawBuf.get/.set` are UB if `i >= size(b)`;
caller checks via `RawBuf.size`. Bounds-check insertion is a
future axis, no backlog item yet.
Bounds checks are **not** in scope: `RawBuf.get/.set` are UB if `i
>= size(b)`; caller checks via `RawBuf.size`. A future axis, no
backlog item yet.
## Testing strategy
**raw-buf.2 (rename):**
- All existing workspace tests pass unchanged — the rename is a
pure refactor. Zero test-count change. The crate-rename's
failure mode is "the workspace does not build / existing tests
break", caught by `cargo build --workspace` + `cargo test
--workspace`.
**raw-buf.3 (RawBuf end-to-end):**
- Round-trip: `raw_buf_module_round_trips` (mirror of
`kernel_stub_module_round_trips` in `design_schema_drift.rs`) —
parse → serialise → round-trip; assert `kernel == true`, name
`raw_buf`, and `RawBuf` TypeDef `param_in` for `a` contains all
of Int/Float/Bool.
- E2E `raw_buf_int_e2e`: the worked consumer program — `ail check
&& ail build && ail run` → prints `60`.
- E2E `raw_buf_float_e2e` / `raw_buf_bool_e2e`: Float and Bool
element variants (Bool catches any i1/i8 packing question).
- E2E `raw_buf_param_in_reject_e2e`: the Str-element reject
fixture — `ail check` exits non-zero with
`param-not-in-restricted-set` in stderr.
- Drop ratification: a consumer that allocates a RawBuf and lets
it go out of scope without a leak — re-uses the existing
leak-check harness, no new infra.
**raw-buf.3 (mechanism):**
- Mono unit test: a type-scoped poly intrinsic op mints the
scope-qualified symbol (`StubT_peek__Int`, `StubT_peek__Float`) —
asserts the new mangling directly, no running program needed.
- Bijection: `intercepts_bijection_with_intrinsic_markers` stays
green with the 12 new markers + 12 new entries (the test forces
the exact mangled-name match).
- `workspace_pin` count assertion 4 → 5 (+ `contains_key("raw_buf")`).
green with the `peek` marker expanded to its 2 scope-qualified
entries (proves the 1-marker→N-entries expansion).
- `kernel_stub_module_round_trips` updated for the added `peek` fn
(parse → serialise → round-trip holds).
- Full suite green; no workspace-count change (peek is added to the
existing stub, no new module).
**raw-buf.4 (retirement):**
- `workspace_pin` re-baselines 5 → 4 (raw_buf in, kernel_stub
out); `contains_key("kernel_stub")` assertion removed,
`contains_key("raw_buf")` retained.
- `kernel_stub_module_round_trips` deleted (its `parse_kernel_stub`
callee is gone; `raw_buf_module_round_trips` carries the
round-trip invariant forward).
- Bijection stays green after the `answer` marker + entry leave
together.
- The full suite stays green; the diff is a removal, ratified by
"nothing references the stub and everything still builds".
**raw-buf.4 (RawBuf payload + desugar):**
- Round-trip `raw_buf_module_round_trips` (mirror
`kernel_stub_module_round_trips`): assert `kernel == true`, name
`raw_buf`, `RawBuf` TypeDef `param_in` for `a` contains
Int/Float/Bool.
- E2E `raw_buf_int_e2e`: the worked program — `ail check && ail
build && ail run` → prints `60`.
- E2E `raw_buf_float_e2e` / `raw_buf_bool_e2e`: Float and Bool
variants (Bool catches any i1/i8 packing question).
- E2E `raw_buf_param_in_reject_e2e`: the Str reject fixture — `ail
check` exits non-zero with `param-not-in-restricted-set`.
- Term::New desugar ratified by the `(new RawBuf …)` form building
and running (it would hit the now-removed deferral arm otherwise).
- Drop ratification: allocate a RawBuf, let it go out of scope, no
leak (re-uses the existing leak-check harness).
- Bijection green with the 12 RawBuf entries added.
- `workspace_pin` count 4 → 5 (+ `contains_key("raw_buf")`).
**raw-buf.5 (retirement):**
- `workspace_pin` re-baselines 5 → 4 (raw_buf in, kernel_stub out).
- `kernel_stub_module_round_trips` deleted;
`raw_buf_module_round_trips` carries the invariant forward.
- Bijection green after `answer` + `StubT_peek__*` markers + entries
leave together with the stub.
- Full suite green; the diff is a removal.
## Acceptance criteria
The milestone ships when:
1. The worked consumer program runs end-to-end: `ail check && ail
build && ail run` prints `60` (raw-buf.3).
2. The param-in reject fixture exits at `ail check` with the
prep.3 `param-not-in-restricted-set` diagnostic (raw-buf.3).
3. RawBuf's four operations are `(intrinsic)` markers, each paired
with an `INTERCEPTS` entry; `intercepts_bijection_with_intrinsic_markers`
is green (raw-buf.3).
4. `Term::New` no longer reaches codegen — the desugar eliminates
it and both deferral arms (`lib.rs:2094` + `lib.rs:3296`) are
removed (raw-buf.3).
5. `ailang-kernel-stub` is renamed to the `ailang-kernel`
family-crate (raw-buf.2); `kernel_stub` is retired and `raw_buf`
takes over its ratification roles (raw-buf.4).
build && ail run` prints `60` (raw-buf.4).
2. The param-in reject fixture exits at `ail check` with the prep.3
`param-not-in-restricted-set` diagnostic (raw-buf.4).
3. RawBuf's four ops are `(intrinsic)` markers, each mono'd to a
scope-qualified symbol (`RawBuf_<op>__<T>`) with a matching
`INTERCEPTS` entry; `intercepts_bijection_with_intrinsic_markers`
is green (the mechanism in raw-buf.3, the 12 entries in raw-buf.4).
4. `Term::New` no longer reaches codegen — the desugar eliminates it
and both deferral arms (`lib.rs` ~2094 + ~3296) are removed
(raw-buf.4).
5. `kernel_stub` is retired and `raw_buf` takes over its
ratification roles (raw-buf.5).
6. Workspace test suite green at each iteration boundary, plus the
new tests enumerated in § Testing strategy.
new tests in § Testing strategy.
## Feature-acceptance argument
Applied per `design/contracts/0004-feature-acceptance.md`:
1. **LLM author reaches for it naturally.** RawBuf is the only
path to mutable indexed storage in AILang — the language has no
other "fill N slots and read them back" primitive. The worked
consumer program above is what an LLM author writes for that
need; there is no alternative shape to reach for.
1. **LLM author reaches for it naturally.** RawBuf is the only path
to mutable indexed storage in AILang — the language has no other
"fill N slots and read them back" primitive. The worked consumer
program is what an LLM author writes for that need; there is no
alternative shape to reach for.
2. **Measurable improvement.** Embedding-ABI M5 measured per-tick
FFI at ~206 ns/tick (~658 ms / 3.19M EURUSD ticks). RawBuf as
the batch-FFI primitive amortises that per-tick cost across one
FFI at ~206 ns/tick (~658 ms / 3.19M EURUSD ticks). RawBuf as the
batch-FFI primitive amortises that per-tick cost across one
crossing. The Series milestone (#8) is also blocked on RawBuf;
shipping raw-buf removes that block.
3. **No reintroduced bug class.** Mutation discipline stays
mode-tracked (whitepaper § "RawBuf — the base extension"):
`RawBuf.set` is `own → own`, not effect-tracked. No `RawBuf`
effect is declared. Uniqueness inference rewrites in-place;
shared ownership falls back to copy-on-write (Issue #22). The
pure-core invariant survives: code without a declared effect is
pure. Local reasoning survives: a fn taking `borrow (RawBuf
Int)` and returning `Int` is pure from the caller's view,
because the buffer is not mutated.
3. **No reintroduced bug class.** Mutation stays mode-tracked:
`RawBuf.set` is `own → own`, not effect-tracked; no `RawBuf`
effect is declared. Uniqueness inference rewrites in-place; shared
ownership falls back to copy-on-write (Issue #22). The pure-core
invariant survives (code without a declared effect is pure); local
reasoning survives (a fn taking `borrow (RawBuf Int)` and
returning `Int` is pure from the caller's view). The new
scope-qualified mono symbols *remove* a latent bug class — the
`get__Int`-style collision between different types' identically
named polymorphic ops.