Files
sx/examples/probes/tuple-baseline.sx
agra 40b5fb5f7e docs: tuple syntax cutover — Tuple(...) type, .(...) value, channel-outside-Tuple failables
Rewrite specs.md tuple/failable/pack/UFCS/grammar sections to the new
syntax, update readme.md, and refresh stale tuple references in example
header comments. Also fixes two pre-existing doc inaccuracies surfaced in
review: drop the value-discarding `;` in the tuple-return examples, and
correct the §13 function-type grammar production (optional param list +
optional trailing `!` channel). Optional semantics unchanged.

current/CHECKPOINT-LANG.md logs the cutover.
2026-06-25 18:41:22 +03:00

63 lines
2.9 KiB
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// Feature 1 / Step 0.4 — tuple baseline probe (gate for Decision 2:
// "tuples are first-class for pack storage").
//
// This file is the audit artifact: it exercises every tuple operation the
// canonical `Combined`/`map` body relies on, EXCEPT the two pack/tuple
// projection+spread sugars that are themselves Feature 1 work (documented
// as gaps at the bottom). Everything here RUNS today.
//
// Run: ./zig-out/bin/sx run examples/probes/tuple-baseline.sx
#import "modules/std.sx";
Listenable :: struct { value: i64; } // stand-in element struct
Combined :: struct { sources: Tuple(i32, i32); } // tuple-typed field (Decision 2)
swap :: (a: i64, b: i64) -> Tuple(i64, i64) { .(b, a) }
fst :: (t: Tuple(i64, i64)) -> i64 { t.0 }
main :: () -> i32 {
// ── Block A — primitives (WORKS) ───────────────────────────────
pair := .(40, 2); // inferred positional
print("A.idx {} {}\n", pair.0, pair.1);
named := .(x = 10, y = 20); // named + numeric access
print("A.named {} {} {}\n", named.x, named.0, named.1);
one := .(42); // 1-tuple
print("A.one {}\n", one.0);
a : i64 = pair.0; // element into typed local
print("A.local {}\n", a);
// ── Block B — storage in a struct field (WORKS; core of Decision 2)
c : Combined = ---;
c.sources = .(7, 9); // assign tuple value to field
print("B.field {} {}\n", c.sources.0, c.sources.1);
// ── Block C — return / pass / operators (WORKS) ────────────────
s := swap(1, 2);
print("C.ret {} {}\n", s.0, s.1);
print("C.pass {}\n", fst(.(11, 22)));
print("C.eq {}\n", .(1, 2) == .(1, 2));
cc := .(1, 2) + .(3, 4);
print("C.concat {} {}\n", cc.0, cc.3);
print("C.mem {}\n", 3 in .(1, 2, 3));
0
}
// ── GAPS (Feature 1 work — intentionally NOT exercised above) ──────
//
// G1. Tuple field projection across elements:
// t := .(Listenable.{value=1}, Listenable.{value=2});
// v := t.value; // expected: .(1, 2) — Decision 3 "tuple.field"
// Today: `error: field 'value' not found on type 'tuple'`.
// Needed by canonical `self.sources.value`.
//
// G2. Tuple spread into call args:
// p := .(10, 20);
// add(..p); // expected: add(10, 20) — Decision 3 "..tuple"
// Today: lowers to one `undef` arg → LLVM arity verification failure.
// Needed by canonical `mapper(..sources.value)` and `.(..sources)`.
//
// Both are already scheduled: parsing in Phase 1.2 (PackExpansion node covers
// `.(..pack)` / `..pack.field`), sema in Phase 2.3 ("tuple-spread parallels").
// No separate Feature 1.5 needed — see Step 0.4 triage in CHECKPOINT-LANG.md.