Flip the surface semantics for type-introducer directives: bare
`Foo :: #jni_class("path") { ... }` now means "DEFINE a new Java class
at that path" (sx-side provides the implementations). The `#foreign`
prefix modifier flips it back to "REFERENCE an existing class on the
foreign runtime." Matches how `#foreign` already reads in sx for C
function declarations (`printf :: ... #foreign;`).
Foo :: #foreign #jni_class("path/to/Foo") { ... } // reference
Foo :: #jni_class("path/to/Foo") { ... } // define
Foo :: #jni_main #jni_class("path/to/Foo") { ... } // define + main Activity
Compiler-side changes:
- New `hash_jni_main` lexer token (the launchable-Activity marker).
Existing `hash_foreign` is reused; no new modifier token there.
- `ForeignClassDecl` gains `is_foreign: bool` + `is_main: bool`.
`ForeignMethodDecl` gains `body: ?*Node` so defined-class methods
can carry sx-side implementations (foreign-class methods stay
`;`-terminated).
- Parser learns `tryParseForeignClassPrefix` — peek-and-consume the
modifier tokens, then dispatch to the unchanged
`parseForeignClassDecl` with the flags threaded through.
- Sema rejects two illegal combinations: `#foreign + #jni_main`
(can't be both an external reference and the app's main entry),
and bodied methods on `#foreign` decls (foreign methods are
runtime-provided).
- Lower's foreign-class dispatch errors on non-foreign decls with
a pointer to the runtime-synthesis follow-up; defined-class
codegen (Java class emission, RegisterNatives wiring, manifest
entry generation) lands in a separate session.
Migration:
- `library/modules/platform/android_jni.sx`: all four foreign class
decls (`Activity`, `Window`, `View`, `WindowInsets`) gain `#foreign`.
- `examples/ffi-jni-class-{01..08}*.sx`: every test's `#jni_class` /
`#jni_interface` / `#objc_class` / `#objc_protocol` / `#swift_class`
/ `#swift_struct` / `#swift_protocol` usage gains `#foreign`. All
9 files mechanical perl rename; snapshots unchanged.
Verified locally:
- `zig build test` clean.
- `bash tests/run_examples.sh` 129/129.
- `bash tests/cross_compile.sh` 3/3.
- Chess APK rebuilds, reinstalls, launches on Pixel; safe-area
clearance preserved.
`act.getWindow()` on `act: *Activity` (where `Activity ::
#jni_class("android/app/Activity") { getWindow :: ... }`) should
lower to `#jni_call(*void)(act, "getWindow", "()Ljava/lang/Object;")`
(omitted-env form picking up env from the enclosing `#jni_env`
scope via 2.16b's lexical-direct path). Today's sema reports
"unresolved: 'getWindow'" because foreign-class members aren't
yet wired into the method-resolution path.
The make-green follow-up needs:
- sema: register `ForeignClassDecl.members` so method names
resolve on foreign-class receivers (or suppress the unresolved
fallback for them).
- lower: build a `foreign_class_map` in scan pass; new arm in
`lowerCall`'s method-dispatch site emits a synthetic
`FfiIntrinsicCall { kind: jni_call, args: [target, "name",
"(sig)Ret", method_args...] }` with the descriptor derived via
`jni_descriptor.deriveMethod`.
- type system: `*Activity` resolution path so `inferExprType`
on the receiver returns a known type (likely register foreign
classes as synthetic 0-field structs reusing the struct-type
machinery).
Larger session needed — pausing here at the xfail.
