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
