Brummel
feb941363a
`(app print x)` under --alloc=rc leaked the heap-Str allocated by
`show x` in print's body: the let-binder `s` in
`(let s (app show x) (do io/print_str s))` was never flagged
trackable, so the drop site at scope-close emitted no
`ailang_rc_dec(s)`. Minimal repro `(body (app print 42))` produced
`allocs=1 frees=0 live=1`.
Root cause is two-layer:
1. examples/prelude.ail.json declared the Show class method `show`
without an explicit `ret_mode` on the return type, so serde
defaulted to ParamMode::Implicit. Fix: add `"ret_mode": "own"`
on the Show.show method, parallel to how the heap-Str-producing
builtins (int_to_str, bool_to_str, float_to_str, str_clone,
str_concat) declare it. examples/prelude.ail regenerated via
`ail render` to stay parse-isomorphic with the JSON.
2. crates/ailang-check/src/lib.rs `substitute_rigids` was silently
stripping `param_modes` and `ret_mode` whenever it rebuilt a
`Type::Fn`, so even after the prelude fix, the mono-synthesised
`show__Int / Bool / Str / Float` lost the `Own` annotation
during rigid substitution. Fix: preserve both fields through
the substitution.
RED pin: crates/ail/tests/print_no_leak_pin.rs (test
`alloc_rc_print_int_does_not_leak_show_result_str`) + fixture
examples/print_int_no_leak_pin.ail asserts allocs == frees and
live == 0 for `(body (app print 42))` under --alloc=rc.
Ten mono-body hash pins re-recorded (eq__Int/Bool/Str,
compare__Int/Bool/Str, show__Int/Bool/Str/Float, eq__IntBox) —
the bodies are semantically identical; the canonical JSON now
carries the previously-stripped mode metadata, so the body hash
moves. Re-pinning is bookkeeping for the intentional drift, not
a workaround.
Surfaced 2026-05-14 during the rpe.1 BLOCKED orchestrator run
(Cat A). Existed in latent form since iter 24.3 (when Show + print
shipped); only became user-observable when `(app print ...)` joined
the corpus. cargo test --workspace: 565 / 0 / 3.
Open follow-up flagged for next /audit: grep for `Type::Fn { ..., .. }`
field-spread sites — any other shape that drops modes during
rebuild is a latent instance of the same bug class. Out of scope
for this minimal fix.
117 lines
6.2 KiB
Plaintext
117 lines
6.2 KiB
Plaintext
(module prelude
|
|
(data Ordering
|
|
(doc "Result of a three-way comparison: LT (less than), EQ (equal), GT (greater than). Ships in milestone 23 as the codomain of Ord.compare.")
|
|
(ctor LT)
|
|
(ctor EQ)
|
|
(ctor GT))
|
|
(class Eq
|
|
(param a)
|
|
(doc "Structural equality. Ships in milestone 23 alongside Ord. The primitive `==` operator stays as the surface-level comparator this iter; routing `==` through `Eq.eq` is the declared P2 follow-up (see docs/specs/2026-05-10-23-eq-ord-prelude.md, `Out of scope`).")
|
|
(method eq
|
|
(type (fn-type (params (borrow a) (borrow a)) (ret (con Bool))))))
|
|
(instance
|
|
(class Eq)
|
|
(type (con Int))
|
|
(doc "Eq Int. Body lowers to `icmp eq i64` via the existing primitive `==` dispatch in `lower_eq`.")
|
|
(method eq
|
|
(body (lam (params (typed x a) (typed y a)) (ret (con Bool)) (body (app == x y))))))
|
|
(instance
|
|
(class Eq)
|
|
(type (con Bool))
|
|
(doc "Eq Bool. Body lowers to `icmp eq i1` via the existing primitive `==` dispatch in `lower_eq`.")
|
|
(method eq
|
|
(body (lam (params (typed x a) (typed y a)) (ret (con Bool)) (body (app == x y))))))
|
|
(instance
|
|
(class Eq)
|
|
(type (con Str))
|
|
(doc "Eq Str. The lambda body shape mirrors Int/Bool for round-trip stability, but the codegen intercept in `emit_fn` overrides the body to call `@ail_str_eq` directly — see `try_emit_primitive_instance_body` in `crates/ailang-codegen/src/lib.rs`.")
|
|
(method eq
|
|
(body (lam (params (typed x a) (typed y a)) (ret (con Bool)) (body (app == x y))))))
|
|
(class Ord
|
|
(param a)
|
|
(superclass (class Eq) (type a))
|
|
(doc "Total ordering. Ships in milestone 23 alongside Eq. `compare x y` returns LT, EQ, or GT (the three-ctor Ordering ADT also in the prelude). Decision 11's single-superclass closure requires `instance Eq T` for every `instance Ord T` — the three Ord instances below pair with the three Eq instances shipped in iter 23.2.3.")
|
|
(method compare
|
|
(type (fn-type (params (borrow a) (borrow a)) (ret (con Ordering))))))
|
|
(instance
|
|
(class Ord)
|
|
(type (con Int))
|
|
(doc "Ord Int. The lambda body shape is a placeholder for round-trip stability; the codegen intercept `try_emit_primitive_instance_body::\"compare__Int\"` emits a three-way `icmp slt` / `icmp eq` branch ladder constructing LT / EQ / GT.")
|
|
(method compare
|
|
(body (lam (params (typed x a) (typed y a)) (ret (con Ordering)) (body (term-ctor Ordering EQ))))))
|
|
(instance
|
|
(class Ord)
|
|
(type (con Bool))
|
|
(doc "Ord Bool. Body lowered via `try_emit_primitive_instance_body::\"compare__Bool\"` — `icmp ult i1` LT-test, `icmp eq i1` EQ-test, GT default.")
|
|
(method compare
|
|
(body (lam (params (typed x a) (typed y a)) (ret (con Ordering)) (body (term-ctor Ordering EQ))))))
|
|
(instance
|
|
(class Ord)
|
|
(type (con Str))
|
|
(doc "Ord Str. Body lowered via `try_emit_primitive_instance_body::\"compare__Str\"` — `call i32 @ail_str_compare(ptr, ptr)` then branch on slt-0 / eq-0 against the normalised {-1, 0, +1} return.")
|
|
(method compare
|
|
(body (lam (params (typed x a) (typed y a)) (ret (con Ordering)) (body (term-ctor Ordering EQ))))))
|
|
(class Show
|
|
(param a)
|
|
(doc "Producer of a human-readable Str representation. Ships in milestone 24 with primitive instances for Int/Bool/Str/Float; user types declare their own instance.")
|
|
(method show
|
|
(type (fn-type (params (borrow a)) (ret (own (con Str)))))))
|
|
(instance
|
|
(class Show)
|
|
(type (con Int))
|
|
(method show
|
|
(body (lam (params (typed x (con Int))) (ret (con Str)) (body (app int_to_str x))))))
|
|
(instance
|
|
(class Show)
|
|
(type (con Bool))
|
|
(method show
|
|
(body (lam (params (typed x (con Bool))) (ret (con Str)) (body (app bool_to_str x))))))
|
|
(instance
|
|
(class Show)
|
|
(type (con Str))
|
|
(method show
|
|
(body (lam (params (typed x (con Str))) (ret (con Str)) (body (app str_clone x))))))
|
|
(instance
|
|
(class Show)
|
|
(type (con Float))
|
|
(method show
|
|
(body (lam (params (typed x (con Float))) (ret (con Str)) (body (app float_to_str x))))))
|
|
(fn ne
|
|
(doc "Polymorphic disequality. `ne x y` ≡ not (eq x y). Ships in milestone 23 as the Eq-class free helper.")
|
|
(type (forall (vars a) (constraints (constraint Eq a)) (fn-type (params (borrow a) (borrow a)) (ret (con Bool)))))
|
|
(params x y)
|
|
(body (app not (app eq x y))))
|
|
(fn lt
|
|
(doc "Polymorphic strict-less-than. `lt x y` ≡ case compare x y of LT -> True; _ -> False. Ships in milestone 23 as the Ord-class free helper.")
|
|
(type (forall (vars a) (constraints (constraint Ord a)) (fn-type (params (borrow a) (borrow a)) (ret (con Bool)))))
|
|
(params x y)
|
|
(body (match (app compare x y)
|
|
(case (pat-ctor LT) true)
|
|
(case _ false))))
|
|
(fn le
|
|
(doc "Polymorphic less-than-or-equal. `le x y` ≡ case compare x y of GT -> False; _ -> True. Ships in milestone 23 as the Ord-class free helper.")
|
|
(type (forall (vars a) (constraints (constraint Ord a)) (fn-type (params (borrow a) (borrow a)) (ret (con Bool)))))
|
|
(params x y)
|
|
(body (match (app compare x y)
|
|
(case (pat-ctor GT) false)
|
|
(case _ true))))
|
|
(fn gt
|
|
(doc "Polymorphic strict-greater-than. `gt x y` ≡ case compare x y of GT -> True; _ -> False. Ships in milestone 23 as the Ord-class free helper.")
|
|
(type (forall (vars a) (constraints (constraint Ord a)) (fn-type (params (borrow a) (borrow a)) (ret (con Bool)))))
|
|
(params x y)
|
|
(body (match (app compare x y)
|
|
(case (pat-ctor GT) true)
|
|
(case _ false))))
|
|
(fn ge
|
|
(doc "Polymorphic greater-than-or-equal. `ge x y` ≡ case compare x y of LT -> False; _ -> True. Ships in milestone 23 as the Ord-class free helper.")
|
|
(type (forall (vars a) (constraints (constraint Ord a)) (fn-type (params (borrow a) (borrow a)) (ret (con Bool)))))
|
|
(params x y)
|
|
(body (match (app compare x y)
|
|
(case (pat-ctor LT) false)
|
|
(case _ true))))
|
|
(fn print
|
|
(doc "Polymorphic console-print helper. `print x` ≡ `do io/print_str (show x)` with an explicit let-binder around `show x` for heap-Str RC discipline per eob.1 Str carve-out. Ships in milestone 24 as the second half of the Show prelude.")
|
|
(type (forall (vars a) (constraints (constraint Show a)) (fn-type (params (borrow a)) (ret (con Unit)) (effects IO))))
|
|
(params x)
|
|
(body (let s (app show x) (do io/print_str s)))))
|