Three new SX primitives wrapping Unix socket APIs:
- socket-connect host port → "sockN" (TCP client)
- socket-server ?host? port → "sockN" listening socket (SO_REUSEADDR, backlog 8)
- socket-accept server-chan → {:channel :host :port}
Sockets reuse the channel_table from Phase 5, so existing channel-read/
write/close/select all work on them. Host arg supports localhost,
0.0.0.0, IPv4 literal, or gethostbyname lookup.
Tcl `socket` command:
- socket host port → TCP client
- socket -server cb port → listening socket; auto-registers a fileevent
on the server channel that fires `_sock-do-accept SRV CB` per readable
event. _sock-do-accept (internal) accepts the pending client and calls
the user's callback as `cb client-chan host port`.
puts channel detection now also recognizes "sockN" prefix (was only
"fileN") and dispatches to channel-write.
+4 idiom tests: socket-server-fires-callback, socket-client-server-
roundtrip, socket-server-peer-host, socket-multiple-connections.
358/358 green.
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
New SX primitive io-select-channels(read-list write-list timeout-ms) wrapping
Unix.select on the registered channel table. Returns {:readable :writable}.
Tcl event loop implemented purely in Tcl (no sx_server.ml changes):
- fileevent $chan readable|writable script (or "" to unregister)
- fileevent $chan event (1 arg) returns the registered script
- after ms script — schedule one-shot timer
- after ms (no script) — sleep, driving event loop in the meantime
- vwait varname — block until var is set/changed, handlers run between polls
- update — non-blocking event drain (poll-timeout=0)
State on interp: :fileevents (list of (chan event script)) and :timers
(sorted list of (expiry-ms script)).
tcl-event-step is the inner loop: expire timers, build fd lists from
:fileevents, call io-select-channels with computed timeout, run ready
handlers. vwait polls every 1000ms or until var changes.
Scoped to script mode by design — vwait from inside a server-handled
command does not interact with sx_server's stdin scheduler.
+5 idiom tests: after-vwait-timer, after-multiple-timers-update,
fileevent-readable-fires, fileevent-query-script,
after-cancel-via-vwait-timing. 354/354 green.
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
When a `perform` fired inside a tree-walked eval_expr path — sf_letrec init
exprs / non-last body exprs, expand_macro body, qq_expand unquote,
sf_dynamic_wind / sf_scope / sf_provide bodies — cek_run raised
"IO suspension in non-IO context" and swallowed the suspension. The hook
that converts the CEK suspended state to VmSuspended (so the outer driver
sees it as a resumable suspension object) was defined in sx_vm.ml but
never invoked from cek_run.
Repro in Node.js (hosts/ocaml/browser/test_letrec_resume.js):
(letrec ((x (perform {:op "io"}))) "ok") ;; threw the error
(letrec ((x 1)) (perform {:op "io"}) "after") ;; threw the error
The originally reported browser symptom — "[sx] resume: Not callable: nil"
after hs-wait resumes inside a letrec — was the same root cause showing
through the JIT/VM resume path instead of as a top-level error.
Fix: cek_run and cek_run_iterative now check !_cek_io_suspend_hook and
invoke it when the loop terminates in a suspended state. The hook (set by
sx_vm.ml in the browser, by run_tests.ml in the test runner) converts the
suspension to VmSuspended / resolves IO synchronously. When the hook is
unset (pure-CEK harness), the legacy Eval_error is raised so misuse stays
visible.
Also patches:
- hosts/ocaml/bootstrap.py — regex-patches the transpiled cek_run on regen
so the fix survives a fresh `python3 hosts/ocaml/bootstrap.py` cycle.
- hosts/ocaml/browser/sx_browser.ml — api_eval / api_eval_vm / api_eval_expr
now catch VmSuspended and surface a clean error string (K.eval has no
driver to resume; callers who want resumption use callFn).
Tests:
- spec/tests/test-letrec-resume-treewalk.sx — 7 CEK-level regression tests
covering letrec init / non-last body, scope/provide bodies, sibling
fn-after-perform. All 7 fail in baseline ("IO suspension in non-IO
context"), all 7 pass with the fix.
- hosts/ocaml/browser/test_letrec_resume.js — 13 WASM kernel tests via
callFn driveSync, including the wait-boot pattern from the briefing.
All 13 pass.
Suite results: 4557 pass / 1338 fail (was 4550 / 1339); +7 new passes,
-1 flaky timeout (hs-upstream-if sieve), no regressions.
After the Integer/Number numeric tower split (c70bbdeb), the bytecode
compiler emits :upvalue-count as Integer, but the VM and SXBC loader
only matched Number. The fallback `_ -> 0` made the VM skip reading
upvalue descriptors entirely, so the IP advanced into raw upvalue
bytes which were then misread as opcodes.
Symptom: JIT runs of nested closures (curried functions, Y combinator,
component bodies that close over outer let-bindings) produced "VM:
CONST index N out of bounds (pool size M)" with N values like 256,
4096, 5120, 12800, 13056 — all of the form `byte | (opcode << 8)`,
i.e. an upvalue descriptor (lo) followed by the next instruction's
opcode (hi) being read as a u16 operand.
Fix all five sites that decode upvalue-count to also accept Integer:
- hosts/ocaml/lib/sx_vm.ml: OP_CLOSURE handler, trace_run, disassemble
- hosts/ocaml/lib/sx_vm_ref.ml + hosts/ocaml/sx_vm_ref.ml + bootstrap_vm.py:
vm_create_closure preamble (the bootstrap source-of-truth and both
generated copies)
- hosts/ocaml/browser/sx_browser.ml: SXBC loader's parse_kv
Test impact: JIT 3848 -> 4538 passing (+690). No-JIT unchanged at 4550.
The previously-failing curried/Y/higher-order tests in
spec/tests/test-cek-advanced.sx now pass under --jit and serve as
regression coverage.
This fixes a real current bug. The 28-day-old memory file describing
parser-combinator JIT bugs predates the numeric tower split and
described a different problem; with this fix the parser-combinator
broken-name list (`_jit_is_broken_name` in sx_vm.ml) is no longer
strictly required for correctness, but keeping it avoids a TIMEOUT
regression in one hyperscript test, so it remains in place.
11 new SX primitives in sx_primitives.ml wrapping Unix.openfile/read/write/
lseek/set_nonblock: channel-open/close/read/read-line/write/flush/seek/tell/
eof?/blocking?/set-blocking!.
Tcl runtime now uses real channel ops:
- open ?-mode? returns "fileN" handle (modes r/w/a/r+/w+/a+)
- close/read/gets/puts/seek/tell/eof/flush wired through
- new fconfigure command supports -blocking 0|1
- puts dispatches to channel-write when first arg starts with "file"
- gets command registration fixed (was pointing to old stub)
eof-returns-1 coro test updated to match real Tcl semantics (eof flips
only after a read hits EOF).
Test runner timeout bumped 180s→1200s (post-merge JIT is slow).
+7 idiom tests covering write+read, gets-loop, seek/tell, eof-after-read,
append mode, seek-to-end, fconfigure-blocking. 349/349 green.
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
The bytecode compiler emitted OP_CALL_PRIM (52) for every primitive call, even
for arithmetic and comparison hot-paths. The VM had specialized opcodes
(OP_ADD, OP_SUB, OP_EQ, etc.) defined but unused.
- lib/compiler.sx (compile-call): emit specialized 1-byte opcode when the
primitive name + arity matches one of {+, -, *, /, =, <, >, cons, not, len,
first, rest}. Falls back to CALL_PRIM otherwise. fib bytecode: 50 → 38 bytes.
- hosts/ocaml/lib/sx_compiler.ml: mirror change in the auto-generated OCaml
compiler so SXBC export from mcp_tree uses the same emission.
- hosts/ocaml/lib/sx_vm.ml: extend OP_ADD/SUB/MUL/DIV to handle Integer+Integer
(not just Number+Number). Inline OP_EQ via Sx_runtime._fast_eq. Inline
OP_LT/GT mixed-numeric comparisons. Avoids Hashtbl lookup on the fallback
path for the common integer cases that dominate tight loops.
- hosts/ocaml/bin/bench_vm.ml: VM-only benchmark — loads compiler.sx via CEK,
JIT-compiles each fn, measures Sx_vm.call_closure throughput.
Median improvements (best of 3 runs of 9-min, bench_vm.exe):
fib(22) 107.87ms → 33.13ms -69%
loop(200000) 429.64ms → 161.16ms -62%
sum-to(50000) 72.85ms → 36.74ms -50%
count-lt(20000) 28.44ms → 17.58ms -38%
count-eq(20000) 37.23ms → 15.46ms -58%
Tests: 4550/4550 OCaml passing (unchanged). Zero regressions.
Last step in the sx-improvements roadmap — all 14 steps complete.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
Added short aliases make-buffer / buffer? / buffer-append! / buffer->string /
buffer-length on both OCaml and JS hosts, sharing the existing StringBuffer
value type. buffer-append! auto-coerces non-strings via inspect.
Rewrote the OCaml host inspect function to walk a single shared Buffer.t
instead of allocating O(n) intermediate strings via String.concat at every
recursion level. inspect underlies sx-serialize and error-path formatting,
so this benefits the tightest serialization paths.
Median improvements (bin/bench_inspect.exe, best-of-3 of 9-run min):
tree-d8 (75KB): 5.31ms -> 1.30ms (-76%)
tree-d10 (679KB): 81.89ms -> 16.02ms (-80%)
dict-1000: 0.80ms -> 0.31ms (-61%)
list-2000: 0.74ms -> 0.33ms (-55%)
Tests: OCaml 4545 -> 4550. JS 2591 -> 2596. Zero regressions.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
CEK frames were already records (cek_frame in sx_types.ml), so the actual
hot-path bottleneck was prim_call "=" [...] in step_continue/step_eval
dispatch: each step did a Hashtbl lookup + 2x list cons + pattern match
just to compare frame-type strings.
Added a short-circuit fast path in prim_call (sx_runtime.ml) for the
hot operators: =, <, >, <=, >=, empty?, first, rest, len. These bypass
the primitives Hashtbl entirely and dispatch directly on value shape.
Inlined _fast_eq for scalar/string equality, which dominates frame-type
dispatch comparisons.
Added bin/bench_cek.exe with five tight-loop benchmarks (fib, loop,
map, reduce, let-heavy). Median of 7 runs:
fib(18) 2789ms -> 941ms (-66%)
loop(5000) 2018ms -> 620ms (-69%)
map sq xs(1000) 108ms -> 48ms (-56%)
reduce + ys(2000) 72ms -> 10ms (-86%)
let-heavy(2000) 491ms -> 271ms (-45%)
Tests: 4545/4545 passing baseline preserved (1339 pre-existing failures
unchanged).
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
Emit a warning when a `match` expression on an ADT value misses one
or more constructors and lacks an `else`/`_` clause. Behaviour is
non-fatal — the match still runs, the warning goes to stderr.
- spec/evaluator.sx: helpers `match-clause-is-else?`, `match-clause-ctor-name`,
`match-warn-non-exhaustive`, `match-check-exhaustiveness`. The latter
reads the `*adt-registry*` (already populated by `define-type`),
collects constructor patterns from clauses, and dedupes via an
`*adt-warned*` env-bound dict so each (type, missing-set) warns once.
Wired into `step-sf-match` via a `do` block before clause dispatch.
- hosts/javascript/platform.py: `host-warn` primitive (`console.warn`)
+ matching `hostWarn` js-id helper so the JS-transpiled spec code
can call it directly. Spec code reaches JS via `sx_build target=js`.
- hosts/ocaml/lib/sx_runtime.ml + sx_primitives.ml: `host-warn` runtime
helper (`prerr_endline`) and registered primitive.
- hosts/ocaml/lib/sx_ref.ml: HAND-PATCHED. `step_sf_match` now calls
a hand-written `match_check_exhaustiveness` that handles both
`AdtValue` and back-compat dict-shape ADT values. The OCaml side
is *not* retranspiled because regenerating sx_ref.ml drops
several preamble fixes (seq_to_list, string->symbol mangling,
empty-dict literal bug). Future retranspile must reapply this patch.
- spec/tests/test-adt.sx: 5 new tests covering exhaustive,
non-exhaustive (warning is non-fatal), `else` suppression,
partial coverage with one missing constructor, and `_` wildcard
suppression. Tests assert return values only — warnings go to
stderr and are not captured.
Warning format: `[sx] match: non-exhaustive — TypeName: missing Ctor1, Ctor2`
Both hosts emit identical messages.
Tests: OCaml 4540 → 4545 (+5), JS 2586 → 2591 (+5). Zero regressions.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
Native algebraic data type representation in the OCaml SX evaluator.
Replaces the dict-based shim that simulated ADT values via tagged dicts.
- sx_types.ml: add AdtValue variant + adt_value record (av_type, av_ctor,
av_fields). type_of returns the type name (e.g. "Maybe"); inspect renders
as a constructor call (e.g. "(Just 42)" or "(Nothing)").
- sx_runtime.ml: get_val handles AdtValue with :_adt/:_type/:_ctor/:_fields
keys for back-compat with spec-level match-pattern code.
- sx_primitives.ml: dict? returns true for AdtValue (so existing match
dispatch keeps working); new adt? predicate distinguishes ADT values.
- sx_ref.ml: sf_define_type now constructs AdtValue instead of Dict.
Predicates (Name?, Ctor?) and accessors (Ctor-field) match on AdtValue
with proper type/ctor name and field index checks.
- spec/tests/test-adt.sx: 3 new tests covering type-of, adt?, and inspect.
Tests: 4532 passed (was 4529 + 3 new), 1339 failed (unchanged baseline).
All 43 ADT tests pass on the native representation.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
In `resume_vm`'s `restore_reuse`, the saved sp captured by
`call_closure_reuse` was ignored when restoring the caller frame after the
async callback finished. The suspended callee's locals/temps stayed on the
value stack above saved_sp, so subsequent LOCAL_GET/SET in the caller
frame (e.g. letrec sibling bindings waiting on the suspending call) read
stale callee data instead of their own slots. Sibling bindings appeared
nil after a perform/resume cycle on the JIT path used by the WASM
browser kernel.
Fix: after popping the callback result and restoring saved_frames, reset
`vm.sp <- saved_sp` (when sp is above), then push the callback result.
Mirrors the OP_RETURN+sp-reset discipline that sync `call_closure_reuse`
already follows.
New tests in `spec/tests/test-letrec-resume.sx` cover single binding,
sibling bindings, mutual recursion siblings, and nested letrec —
all four pass. Full OCaml run_tests: 4529/5868 (was 4525/5864), zero
regressions.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
In `call_closure_reuse`, the success path used a bare `pop vm` that relied on
OP_RETURN having left the stack at exactly `saved_sp + 1`. When the callee
returns a closure (or hits the bytecode-exhausted fallback path), `vm.sp` can
end up inconsistent with the parent frame's expected layout, corrupting
intermediate values such as parser combinator state in `parse-bind`/`many`/
`seq`.
Fix: read the result at the expected slot, then explicitly reset
`vm.sp <- saved_sp` before returning so the parent frame sees a clean stack
regardless of what the callee left behind.
OCaml run_tests baseline: 4525/5864 unchanged. WASM kernel tests: 24/29
unchanged. No regressions.
28 tests, passes on both JS and OCaml.
- spec/stdlib.sx: pure SX format function
- spec/primitives.sx: format primitive declaration
- lib/r7rs.sx: fix number->string to support optional radix arg
- hosts/ocaml: add format-decimal primitive, load stdlib.sx in test runner
- hosts/javascript: load stdlib.sx in test runner
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
Adds 9 regexp primitives to stdlib.regexp. OCaml: SxRegexp(src,flags,Re.re)
using Re.Pcre; $&/$1 capture expansion in replace. JS: native RegExp
with SxRegexp wrapper; regexp-match returns {:match :start :end :groups}.
32 tests in test-regexp.sx, all pass on both hosts.
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
Adds 13 set primitives to stdlib.sets. OCaml: SxSet as (string,value)
Hashtbl keyed by inspect(val); JS: SxSet wrapping Map keyed by
write-to-string. Structural equality — (make-set '(1 2)) contains 1.
Includes union, intersection, difference, for-each, map.
33 tests in test-sets.sx, all pass on both JS and OCaml.
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
Adds read, write, display, newline, write-to-string, display-to-string
and current-*-port primitives to both JS and OCaml hosts.
JS: sxReadNormalize (#t/#f→true/false), sxReadConvert (()→nil),
sxEq array comparison, sxWriteVal symbol/keyword name fix,
readerMacroGet/readerMacroSet registry in parser platform.
OCaml: sx_write_val/sx_display_val helpers, read/write/display/newline
primitives on port types; parser extended for #t/#f and N/D rationals.
42 new tests (test-read-write.sx), all passing on JS and OCaml.
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
SxRational type in OCaml (Rational of int * int, stored reduced, denom>0)
and JS (SxRational class with _rational marker). n/d reader syntax in
spec/parser.sx. Arithmetic contagion: int op rational → rational, rational
op float → float. JS keeps int/int → float for CSS backward compatibility.
OCaml as_number + safe_eq extended for cross-type rational equality so
(= 2.5 5/2) → true. 62 tests in test-rationals.sx, all pass.
JS: 2232 passed. OCaml: 4532 passed (+11 vs pre-fix baseline).
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
Eof sentinel and Port{PortInput/PortOutput} in sx_types.ml. All 15 port
primitives in sx_primitives.ml. type_of/inspect updated. 39/39 port tests
pass (4532 total, +39, zero regressions).
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
gensym_counter ref + gensym/string->symbol/symbol->string/intern/symbol-interned?
primitives in sx_primitives.ml. Fix ListRef case in seq_to_list on both
sx_ref.ml and sx_primitives.ml. 19 new tests in test-gensym.sx.
OCaml 4450/1080, JS 2205/2497, zero regressions.
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
25 tests pass on both JS and OCaml hosts. Uses dict marker
{:_values true :_list [...]} for 0/2+ values; 1 value passes
through directly. step-sf-define extended to desugar shorthand
(define (name params) body) forms on both hosts.
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
Hand-write sf_define_type in bootstrap.py FIXUPS (skipped from transpile
because the spec uses &rest params and empty-dict literals the transpiler
can't emit). Registers define-type via register_special_form. Adds
step_limit/step_count to PREAMBLE (referenced by sx_vm.ml/run_tests.ml).
172 assertions pass (test-adt). Full suite: 4280/1080 (was 4243/1117).
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
OCaml: StringBuffer of Buffer.t in sx_types.ml; 5 primitives in
sx_primitives.ml (make-string-buffer, string-buffer?, string-buffer-append!,
string-buffer->string, string-buffer-length); inspect case added.
JS: SxStringBuffer with array+join backend; _string_buffer marker for
typeOf dispatch and dict? exclusion (also excludes _vector from dict?).
spec/primitives.sx: 5 define-primitive entries.
17/17 tests pass on both OCaml and JS.
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
- sx_types.ml: CallccContinuation gains winders depth int field
- sx_runtime.ml: make_callcc_continuation(captured, winders_len),
callcc_continuation_winders_len accessor; get_val maps after-thunk,
winders-len, body-result to cf_f/cf_extra/cf_name
- sx_ref.ml: step_limit/step_count restored; make_wind_after_frame and
make_wind_return_frame now store their args in the CekFrame fields
- transpiler.sx: after-thunk→cf_f, winders-len→cf_extra,
body-result→cf_name for future bootstrap runs
- 8 new dynamic-wind tests pass (OCaml), 235/235 no regressions
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
vector-ref and vector-set! now raise Eval_error on out-of-bounds index instead of
an OCaml array exception. vector-copy accepts optional start and end parameters for
slicing (R7RS §6.8). spec/primitives.sx doc updated to reflect slice params.
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
Adds regex-compile/test/exec/match-all/replace/replace-fn/split/source/flags.
Opaque dict handle {:__regex__ true :id :source :flags}; compiled Re.re
cached in a primitives-local table. Replacement supports $&, $1-$9, $$.
Flags: i (CASELESS), m (MULTILINE), s (DOTALL). g is a runtime flag handled
in replace. u (unicode) skipped for now.
Unblocks js-on-sx's regex-platform-override! hook — the JS RegExp shim can
now delegate to real regex instead of the substring stub.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
Shared formatter in sx_types.ml. Small integer-valued floats still print
as plain ints; floats outside safe-int range (|n| >= 1e16) now print as
%.17g (full precision) instead of silently wrapping to negative or 0.
Non-integer values keep %g 6-digit behavior — no existing SX tests regress.
Unblocks Number.MAX_VALUE / Math.pow(2,N) style tests in js-on-sx where
iterative float loops were collapsing to 0 at ~2^63.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
JIT-vs-CEK test parity: both now pass 3938/534 (identical failures).
Three fixes in sx_vm.ml + run_tests.ml:
1. OP_CALL_PRIM: fallback to Sx_primitives.get_primitive when vm.globals
misses. Primitives registered after JIT setup (host-global, host-get,
etc. bound inside run_spec_tests) become resolvable at call time.
2. jit_compile_lambda: early-exit for anonymous lambdas, nested lambdas
(closure has parent — recreated per outer call), and a known-broken
name list: parser combinators, hyperscript parse/compile orchestrators,
test helpers, compile-timeout functions, and hs loop runtime (which
uses guard/raise for break/continue). Lives inside jit_compile_lambda
so both the CEK _jit_try_call_fn hook and VM OP_CALL Lambda path
honor the skip list.
3. run_tests.ml _jit_try_call_fn: catch TIMEOUT during jit_compile_lambda.
Sentinel is set before compile, so subsequent calls skip JIT; this
ensures the first call of a suite also falls back to CEK cleanly when
compile exceeds the 5s test budget.
Also includes run_tests.ml 'reset' form helpers refactor (form-element
reset command) that was pending in the working tree.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
Previously these primitives threw Eval_error if either arg was non-string.
Now they return false, preventing crashes when DOM attributes return nil
values during element processing (e.g. htmx-boot-subtree! iterating
elements with undefined attribute names).
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
When an error occurs during resumed VM execution (after perform/hs-wait),
resume_vm now checks the VM's handler_stack. If a handler exists (from a
compiled guard form's OP_PUSH_HANDLER), it unwinds frames and jumps to
the catch block — exactly like OP_RAISE. This enables try/catch across
async perform/resume boundaries.
The guard form compiles to OP_PUSH_HANDLER which lives on the vm struct
and survives across setTimeout-based async resume. Previously, errors
during resume escaped to the JS console as unhandled exceptions.
Also restored guard in the test runner (was cek-try which doesn't survive
async) and restored error-throwing assertions in run-action.
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
The guard form (call/cc + handler-bind expansion) doesn't survive async
IO suspension — the CEK continuation from guard's call/cc captures frames
that become invalid after the VM resumes from hs-wait. Replacing guard
with cek-try (which compiles to VM-native OP_PUSH_HANDLER/OP_POP_HANDLER)
avoids the CEK boundary crossing.
The test runner now executes: suspends on hs-wait, resumes, runs test
actions, and test assertions fire correctly. The "Not callable: nil"
error is eliminated. Remaining: test assertion errors from iframe content
not loading fast enough (timing issue, not a framework bug).
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
The Not callable: nil error happens on a stub VM (frames=[], sp=0) during
cek_resume with 12 CEK kont frames. The error is from a reactive signal
subscriber (reset! current ...) that triggers during run vm after resume.
The subscriber callback goes through CEK via cek_call_or_suspend and the
CEK continuation tries to call nil.
This is a reactive subscriber notification issue, not a perform/resume
frame management issue. The VM frames are correctly restored — the error
happens during a synchronous reset! call within the resumed VM execution.
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
