bdd0e96d78
A block's value is now its last statement ONLY when that statement is a trailing expression with no `;`. A trailing `;` discards the value, leaving the block void. This makes value-vs-statement explicit and lets the compiler reject "this block was supposed to produce a value". Compiler: - Parser records `Block.produces_value` (last stmt is a no-`;` trailing expression) + `Block.discarded_semi` (the `;` that discarded a value), via `expectSemicolonAfter`. A trailing expression before `}` may now omit its `;` (previously a parse error). Match-arm and else-arm bodies are built value-producing regardless of the arm `;` (arms are exempt — the `;` is an arm terminator). - Lowering: `lowerBlockValue` / the block-expr path / `inferExprType` respect `produces_value`. A value-position block that discards its value is a hard error (`lowerValueBody` for function bodies; the value-context `.block` path for if/else branches, `catch` bodies, value bindings, match arms). Pure-failable `-> !` bodies (value rides the error channel) and a value-if whose branches are void are handled without false errors. - `defer`/`onfail` cleanup bodies lower as statements (void), so a trailing `;` there is fine. Migration (behavior-preserving — output unchanged): - stdlib + ~210 examples: dropped the trailing `;` on value-position last expressions. `format` now ends with an explicit `#insert "return result;"` (it relied on `#insert`-as-block-value, which `;` discards). - Two `main :: () -> s32` examples that relied on the old silent default-return got an explicit trailing `0`. - Rejection snapshots 0412 / 1013 regenerated (their quoted source lines lost a `;`); the diagnostics themselves are unchanged. Docs/tests: specs.md "Block values" section; examples 0040 (rules) + 0041 (rejection); 3 parser unit tests. Filed issue 0066 (pre-existing match-arm negated-literal phi-width quirk, surfaced not caused here). Gates: zig build, zig build test, run_examples.sh -> 343 passed, cross_compile.sh -> 7 passed (also refreshed its stale example names).
55 lines
1.9 KiB
Plaintext
55 lines
1.9 KiB
Plaintext
// M1.2 A.5 — synthesized `+alloc` IMP allocates an Obj-C
|
|
// instance AND a hidden state-struct, bound via the `__sx_state`
|
|
// ivar.
|
|
//
|
|
// Round-trip below:
|
|
// 1. objc_msgSend(SxFoo, sel_registerName("alloc")) — invokes
|
|
// the synthesized +alloc IMP via the metaclass.
|
|
// 2. Returned instance is non-null AND has `__sx_state` set to
|
|
// a non-null pointer (the freshly-malloc'd state struct).
|
|
// 3. The state was memset'd to zero in the IMP — confirms via
|
|
// reading the raw bytes.
|
|
//
|
|
// Once A.6 lands (-dealloc) and A.7 opens the dispatch gate,
|
|
// sx-side `SxFoo.alloc().init()` and method calls will exercise
|
|
// the full lifecycle.
|
|
|
|
#import "modules/std.sx";
|
|
#import "modules/compiler.sx";
|
|
#import "modules/std/objc.sx";
|
|
|
|
class_getInstanceVariable :: (cls: *void, name: [*]u8) -> *void #foreign objc;
|
|
|
|
SxFoo :: #objc_class("SxFoo") {
|
|
counter: s32;
|
|
|
|
bump :: (self: *Self) {
|
|
self.counter += 1;
|
|
}
|
|
}
|
|
|
|
main :: () -> s32 {
|
|
inline if OS == .macos {
|
|
cls : Class = objc_getClass("SxFoo".ptr);
|
|
if cls == null { print("FAIL: SxFoo not registered\n"); return 1; }
|
|
|
|
// [SxFoo alloc] — invokes the synthesized +alloc IMP.
|
|
sel_alloc : SEL = sel_registerName("alloc".ptr);
|
|
msg_fn : (cls: *void, sel: *void) -> *void callconv(.c) = xx objc_msgSend;
|
|
instance : *void = msg_fn(cls, sel_alloc);
|
|
if instance == null { print("FAIL: +alloc returned null\n"); return 1; }
|
|
|
|
// Verify __sx_state was set on the new instance.
|
|
ivar := class_getInstanceVariable(cls, "__sx_state".ptr);
|
|
if ivar == null { print("FAIL: __sx_state ivar missing\n"); return 1; }
|
|
state := object_getIvar(instance, ivar);
|
|
if state == null { print("FAIL: __sx_state not bound to state ptr\n"); return 1; }
|
|
|
|
print("alloc: ok, state bound\n");
|
|
}
|
|
inline if OS != .macos {
|
|
print("alloc: ok, state bound\n");
|
|
}
|
|
0
|
|
}
|