The Chez atom record gains watches (an alist of key->fn) and validator
slots. swap!/reset! now validate the candidate value before storing and
notify watches after, in the seed's order (core_refs.janet) — the watch fn
is called (key ref old new). compare-and-set!/swap-vals!/reset-vals! route
through reset!/swap! so they validate + notify too.
add-watch/remove-watch/set-validator!/get-validator are native here and
re-asserted in post-prelude.ss: the clojure.core overlay implements them via
jolt.host/ref-put! on (get atom :watches), a Janet-table mutation a Chez atom
record can't answer, so its def-var! would otherwise clobber these. set-
validator! validates the current value immediately (Clojure throws if already
invalid).
Parity 2150 -> 2154, 0 new divergences. New test/chez/_atomwatch.janet 10/10.
The (class x) native and the clojure.walk port were explored this increment
but deferred: class alone makes the String-class-token corpus cases emit-and-
run with a wrong value (the bare token doesn't resolve yet) — filed jolt-13zk
to land the native together with token resolution; clojure.walk is blocked on
list? + map-entry-as-vector (jolt-75sv).
The dominant prelude-parity crash bucket was 'apply non-procedure jolt-nil':
core fns calling seed-native seq fns (core_coll.janet) that have no Chez RT
shim, so var-deref returns jolt-nil. A static scan of the assembled prelude
turned up 52 referenced-but-undefined clojure.core names.
host/chez/natives-seq.ss shims the safe seq fns over the existing seq layer:
mapcat, take-while, drop-while, partition (collection arities only — the 1-arg
transducer forms are jolt-kxsr), and sort (compare default; a comparator may
return a 3-way number or a boolean less-than). reduced/reduced? is a jolt-reduced
record in seq.ss that reduce short-circuits on and deref unwraps, so unreduced
works. identical? = jolt= (the seed's definition).
Deferred list?: a Chez lazy seq and a list are both cseq, so it can't be told
apart without a distinct list type — a real divergence risk.
Parity 1407 -> 1467/2497, 0 new divergences. emit-test 263/263.
Emit every non-macro clojure.core form through the live analyzer -> Chez emit
pipeline as a def-var! prelude (prelude mode, tier dependency order), load it
before a user expression, and you get an -e-capable jolt-chez: analysis on Janet,
execution on Chez. driver/emit-core-prelude assembles it (each form behind a
silent load guard so the Phase-2 multimethod forms don't break the rest);
bin/jolt-chez is the -e CLI, caching the prelude on disk keyed by source hash.
run-corpus-prelude.janet is the full parity gate this opens, the prelude-backed
sibling of run-corpus-chez. First baseline: 1220/2497 evaluated cases pass, 0 new
divergences (10 allowlisted: dynamic vars, class names, eval-order — deferred
Phase 2). The rest is the punch-list: ~360 emit-fail (real host interop, out of
the analyzer subset) and ~900 runtime crashes, mostly core fns calling
host-coupled seed natives with no Chez shim yet (str/format/vec, transients).
Follow-ups jolt-t6cr/kl2l/q3w8/9ls5.
Two shims landed to get the prelude to load and run. atoms.ss: atom/deref/swap!/
reset! (+ the compare/vals kernel) — needed at load time for
global-hierarchy = (atom (make-hierarchy)). predicates.ss: the type predicates +
name/namespace/boolean the overlay assumes are seed natives, matching the seed's
strict semantics. post-prelude.ss re-asserts char?/atom? after the prelude: the
overlay implements those by reading :jolt/type, which is false for Chez-native
chars/atoms, so its def-var! would clobber the correct native versions.
Per-case Scheme files are PID-unique so a foreground -e never reads a half-written
file while the gate runs.
