Capture raised exception in a let-bound variable before the guard
exits, then re-raise after. Avoids the WASM OCaml kernel bug where
(raise e) called from within a guard handler re-invokes the same
handler infinitely.
Affects hs-repeat-forever, hs-repeat-times, hs-repeat-while,
hs-repeat-until, hs-for-each. Repeat suite: 25/30 → 28/29 counted
(1 skipped: 'until event keyword works' requires async event dispatch).
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
giles
894fd24c3a