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sx/examples/errors/1016-errors-onfail.sx
agra 66bdc70bf1 test: group examples into per-category folders
Move examples/*.sx and their expected/ snapshots into per-category
subfolders (examples/<category>/...). Folder = leading filename token,
with ffi-objc/ffi-jni kept whole; filenames are unchanged. The corpus
runner and LSP sweep now discover each category's expected/ dir, while
issues/ stays flat. Example 1058's repo-root-relative companion import
is made file-relative. Path strings embedded in 164 snapshots were
regenerated (path-only changes). Test-layout docs in CLAUDE.md updated.
2026-06-21 14:41:34 +03:00

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// `onfail` — cleanup that runs only when an error LEAVES the enclosing block
// (ERR step E1.7). Unlike `defer` (which runs on every exit), `onfail` fires
// on an error exit — a `raise` or a propagating `try` — and is skipped on
// success. On an error exit `defer` and `onfail` run interleaved in reverse
// declaration order. `onfail (e) { … }` binds the in-flight error tag.
// (Per-attempt-`try` gating and `or`-chain absorption refine this in E2.4b.)
#import "modules/std.sx";
E :: error { Bad }
inner :: (n: i32) -> !E {
if n < 0 { raise error.Bad; }
return;
}
// defer + onfail interleave on the error path; only defers on success.
run :: (n: i32) -> !E {
defer print("defer A\n");
onfail print("onfail B\n");
defer print("defer C\n");
try inner(n); // n<0 → propagates → onfail fires
return;
}
// `onfail e` binds the tag.
classify :: (n: i32) -> !E {
onfail (e) { if e == error.Bad { print("cleanup: bad\n"); } }
if n < 0 { raise error.Bad; }
return;
}
main :: () -> i32 {
print("[fail]\n");
a := run(-1); // error → defer C, onfail B, defer A
print("[ok]\n");
b := run(7); // success → defer C, defer A (no onfail)
print("[bound]\n");
c := classify(-1); // onfail binding sees Bad
print("[done]\n");
return 0;
}