// Enum-valued value-carrying failables, two paths the bare-success fix (issue // 0097) did NOT originally cover. Regression (issue 0097, attempt-2 review F1+F2). // // F1 — EXPLICIT full failable tuple return `return (.v, error.X)`. The bug was // the inverse of 0097: narrowing the return target to the value type for ALL // value-failables broke the explicit-tuple form (the trailing error element no // longer resolved against the error set → `.unresolved` field → LLVM-emit // panic). The target must stay the FULL failable tuple for an explicit tuple // literal of full arity, and narrow to the value type only for a BARE value. // This pins both branches in one fn: bare-value success + explicit-tuple error. // // F2 — COMPTIME-PARAM ($n) value-failable. The body is INLINED at the call // site (lowerComptimeCall), so the success return takes the inline-return path, // which the original fix skipped — it stored `{value, undef}` (error slot // undefined) on success. Read the error slot at RUNTIME on the success path // (cast, bare `if`, `== error.X`) so an undef slot is caught, not masked by the // `if !e` proof. #import "modules/std.sx"; Color :: enum { red; green; blue; } E :: error { Nope } // F1: bare-value success path AND explicit-tuple error path in one function. classify :: (s: string) -> (Color, !E) { if s == "ok" { return .blue; } // bare value → {2, 0} return (.red, error.Nope); // explicit full tuple → {0, 1} } // F2: comptime parameter forces inline lowering of the body. ct_pick :: ($n: i32, s: string) -> (Color, !E) { if s == "red" { return .red; } // bare value, inline path → {0, 0} if s == "blue" { return .blue; } // bare value, inline path → {2, 0} raise error.Nope; // inline error path → {undef, 1} } main :: () -> i32 { // ── F1 success (bare value, explicit-tuple error fn): error slot 0 ── c, e := classify("ok"); print("F1 ok: err int = {}\n", cast(i64) e); // 0 if e { print("F1 ok bare-if: ERROR (WRONG)\n"); } else { print("F1 ok bare-if: ok\n"); } if !e { print("F1 ok guard: c = {}\n", cast(i64) c); } // 2 (blue) // ── F1 error (explicit tuple): right tag flows, no panic ── c2, e2 := classify("bad"); print("F1 bad: err nonzero = {}\n", cast(i64) e2 != 0); // true (ordinal is program-global, not pinned) if e2 == error.Nope { print("F1 bad: is Nope (ok)\n"); } else { print("F1 bad: not Nope (WRONG)\n"); } print("F1 bad: tag name = {}\n", error_tag_name(e2)); // Nope // ── F2 success (comptime-param, inline path): error slot 0 at runtime ── c3, e3 := ct_pick(7, "red"); print("F2 red: err int = {}\n", cast(i64) e3); // 0 if e3 { print("F2 red bare-if: ERROR (WRONG)\n"); } else { print("F2 red bare-if: ok\n"); } if e3 == error.Nope { print("F2 red == Nope (WRONG)\n"); } else { print("F2 red != Nope (ok)\n"); } if !e3 { print("F2 red guard: c = {}\n", cast(i64) c3); } // 0 c4, e4 := ct_pick(7, "blue"); if !e4 { print("F2 blue: err int = {}, c = {}\n", cast(i64) e4, cast(i64) c4); } // 0, 2 // ── F2 error (comptime-param, inline error path): right tag ── c5, e5 := ct_pick(7, "x"); print("F2 err: err nonzero = {}\n", cast(i64) e5 != 0); // true (ordinal is program-global, not pinned) if e5 == error.Nope { print("F2 err: is Nope (ok)\n"); } else { print("F2 err: not Nope (WRONG)\n"); } return 0; }