Files
sx/examples/0517-packs-pack-reflection-intrinsics.sx
agra 59f0aa7716 std: restructure — std/ modules, namespace tail, std/xml.sx
allocators/fs/process/socket/log/trace/test move under modules/std/
(allocators.sx becomes std/mem.sx; the Allocator protocol moves into
the std.sx prelude, impls stay in mem.sx). New std/xml.sx holds
xml_escape as xml.escape. std.sx gains the carried namespace tail —
flat-importing std.sx now also provides mem./xml./log. — with the
remaining modules (fs/process/socket/json/cli/hash/test) deferred from
the tail until the global last-wins maps are fully own-wins (pulling
them into every closure collides bare names corpus-wide; they stay
direct imports: modules/std/fs.sx etc.). log.sx's internal emit
renamed log_emit (it clobbered consumer fns named emit program-wide).
bundle.sx uses xml.escape via the carried alias. Consumer import paths
swept mechanically; .ir snapshots recaptured for the larger std
closure. m3te + game build unchanged.
2026-06-11 06:10:59 +03:00

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// Variadic heterogeneous type packs — step 3: type-reflection
// intrinsics.
//
// Three comptime helpers used by pack-fn bodies to branch on
// type identity / protocol membership:
//
// type_name(T) -> string // display name of T
// type_eq(T1, T2) -> bool // structural TypeId equality
// has_impl(P, T) -> bool // T has a reachable impl for P
//
// All three fold to compile-time constants and are accepted by
// `tryConstBoolCondition`, so `inline if type_eq(...)` /
// `inline if has_impl(...)` collapse to a single branch at lower
// time — no runtime cost.
//
// `has_impl`'s protocol arg accepts both shapes:
// - plain protocol name: `has_impl(Allocator, CAllocator)`.
// - parameterised call: `has_impl(Wrap(s64), s32)` — the args
// match the impl's protocol type-args exactly.
#import "modules/std.sx";
#import "modules/std/mem.sx";
// User-defined parameterised protocol + an impl, so has_impl can
// confirm parameterised matching works with a known-true case.
Wrap :: protocol(Target: Type) {
wrap :: () -> Target;
}
impl Wrap(s64) for s32 {
wrap :: (self: s32) -> s64 => xx self;
}
main :: () -> s32 {
// type_name — display names.
print("{} {} {}\n", type_name(s64), type_name(string), type_name(bool));
// type_eq — structural equality on TypeIds.
print("{} {} {} {}\n",
type_eq(s64, s64),
type_eq(s64, string),
type_eq(*s64, *s64),
type_eq(*s64, *s32));
// inline-if folds type_eq at lower time.
inline if type_eq(s64, s64) {
print("inline-if folded: same\n");
} else {
print("inline-if folded: different\n");
}
// has_impl — plain protocol (Allocator is unary).
print("Allocator/CAllocator: {}\n", has_impl(Allocator, CAllocator));
print("Allocator/s64: {}\n", has_impl(Allocator, s64));
// has_impl — parameterised protocol (Wrap takes a Target type arg).
print("Wrap(s64)/s32: {}\n", has_impl(Wrap(s64), s32));
print("Wrap(s64)/bool: {}\n", has_impl(Wrap(s64), bool));
print("Wrap(bool)/s32: {}\n", has_impl(Wrap(bool), s32));
return 0;
}