A monomorphic `(new Counter 42)` over a user-defined ADT that declares a
`new` fn passes `ail check` but crashes `ail build --alloc=rc` with
`unknown variable: Counter.new`. Distinct root from #51 (the polymorphic
type-arg drop, fixed by ee4107c) — the #51 fix deliberately left the
monomorphic app-lowering path unchanged.
Root (data-flow traced): the `Term::New` desugar
(crates/ailang-core/src/desugar.rs ~1091) lowers the no-type-arg
monomorphic `(new Counter 42)` to `Term::App { callee:
Var("Counter.new") }`. The checker's TypeDef-first ladder resolves that
dotted callee, so `ail check` is clean; codegen's call-lowering
(`lower_app` / `is_static_callee` in crates/ailang-codegen/src/lib.rs)
does not recognise the dotted `Counter.new` user-ADT constructor callee,
so the `Term::Var` arm falls through to `CodegenError::UnknownVar`
(lib.rs:1712). The documented `lower_app`↔`is_static_callee` lockstep
pair — a check↔codegen disagreement on whether `Counter.new` resolves.
The user `new` fn body IS codegen'd; only the dotted call-site is
unrecognised.
The RED test is minimal and autonomous: a single inline module (user
ADT + `new` fn + a `main` calling `(new Counter 42)`), minimised from
the 3-module 35-symbol kem_2_counter_new.ail reproducer — the
match/print scaffolding is dropped because the crash is at the
call-site lowering, independent of how the result is consumed. Asserts
check passes, build succeeds, the binary runs and prints `ok`. RED at
HEAD (fails at build with the exact symptom). GREEN side resolves the
dotted T.new user-ADT callee at codegen, symmetric to the checker.
refs #53
Brummel
1eff055a0e