Two nREPL divergences the library shakeout surfaced — both have a real host
mechanism on Chez.
Interrupt (jolt-amzy): Chez's engine timer (set-timer + thread-local
timer-interrupt-handler) is polled at procedure-call / loop back-edges, so a
running computation — even a tight loop — can be aborted from another thread.
concurrency.ss adds jolt.host/{make-interrupt, interrupt!, run-interruptible}: an
interrupt token is a shared box; run-interruptible arms a periodic timer whose
handler escapes (call/cc) when the token is set, throwing {:jolt/interrupted true}.
The eval thread is reused, not abandoned. (A thread blocked in a __collect_safe
foreign call only sees it on return — like the JVM not killing native code.)
Thread-local *ns* (jolt-6rld): chez-current-ns is now a Chez thread-parameter, so
each session worker / future has its own current ns (vars stay global, only the
pointer is per-thread). *ns* reads derive from it (dyn-binding.ss), and a bound
*ns* drives chez-current-ns — so (binding [*ns* the-ns] (load-string code))
resolves against the-ns, and concurrent in-ns across threads don't clobber each
other. Single-threaded behaviour is unchanged. All runtime .ss — no re-mint.
Add a thread-safe delay type (concurrency.ss): make-delay wraps a thunk; deref/
force run it once under a lock and cache (JVM delays are thread-safe + memoized).
delay? and realized?-on-a-delay are native; the overlay's `delay` macro
(-> make-delay) and `force` (-> deref) now work. realized? wrapper (post-prelude)
and the deref chain gain a delay arm. Removed the np-delay? stub from
natives-parity.ss (the real type lives in concurrency.ss).
Seed unchanged (no re-mint). zero-Janet 2673->2685, 0 new divergences; Janet gate
+ JVM cert green.
jolt-cf1q.7
Replace the Janet synchronous agent shim (agent = atom, send applies inline) with
JVM-style async agents: send/send-off enqueue an action and a single worker thread
per agent applies them in order; deref reads the current (maybe not-yet-updated)
state without blocking; await blocks until the queue drains. A validator rejection
or a thrown action puts the agent in an error state (agent-error) and halts the
queue; restart-agent clears it. send and send-off share one serialized worker (a
superset of the JVM's fixed/cached pool split). Native versions re-asserted in
post-prelude over the overlay; await/restart-agent are new.
Corpus: the two "send/send-off applies" cases do (send a f) (deref a) with no
await, so they now read state before the action runs — diverging like the JVM
(the suite was literally "synchronous shim"). Allowlisted on both gates; floors
-2 (zero-Janet 2569->2567, prelude 2559->2557). cli-test covers async agents via
await (ordered 100-send dispatch, error capture) — 49/49. Janet gate + JVM cert
green; 0 new divergences on either corpus.
jolt-byjr
future/future-call run the body on a native thread (fork-thread) over the SAME
heap — JVM semantics, not Janet's isolated-heap snapshot. deref blocks on a
mutex+condition latch; timed (deref f ms val) uses an absolute deadline.
promise is a real blocking promise (deref parks until deliver), replacing the
Janet non-blocking atom shim. future?/future-done?/future-cancelled?/future-cancel
/realized? are native (the overlay versions read Janet map keys); re-asserted in
post-prelude over the overlay. pmap/pcalls/pvalues (overlay, over future) light
up for free.
Thread-safety this forces:
- atoms get a per-atom mutex; swap!/swap-vals! are a JVM-style CAS loop (f runs
outside the lock, so a watch/validator can deref the same atom); reset!/
compare-and-set! are atomic.
- the dynamic binding stack becomes a Chez thread-parameter, so each future/thread
has its own; Chez inherits it at fork, giving binding conveyance (the shim also
installs an explicit snapshot).
- Thread/sleep really sleeps now (a worker sleeping doesn't block the parent).
Re-minted the seed: future-call now resolves at compile time, so pmap compiles to
a var-deref instead of the host-static-call fallback that crashed. image.ss
unchanged.
Corpus: the 2 snapshot cases now match the JVM (shared) not Janet (isolated) —
allowlisted on both Chez gates; the two racy future-cancel cases allowlisted;
"promise undelivered" (blocks on JVM/Chez, profile :bucket :timeout) skipped like
:throws. Zero-Janet corpus 2544 -> 2569, 0 new divergences, floor raised. Full
Janet gate + JVM cert green.
jolt-byjr
