Phase 1 engine step 4 — R7RS compatibility primitives for the CEK evaluator.
call/cc: undelimited continuation capture with separate CallccContinuation
type (distinct from delimited shift/reset continuations). Escape semantics —
invoking k replaces the current continuation entirely.
raise/raise-continuable: proper CEK arg evaluation via raise-eval frame.
Non-continuable raise uses raise-guard frame that errors on handler return.
host-error primitive for safe unhandled exception fallback.
Multi-arity map: (map fn list1 list2 ...) zips multiple lists. Single-list
path unchanged for performance. New multi-map frame type.
cond =>: arrow clause syntax (cond (test => fn)) calls fn with test value.
New cond-arrow frame type.
R7RS do: shape-detecting dispatch — (do ((var init step) ...) (test result) body)
desugars to named let. Existing (do expr1 expr2) sequential form preserved.
integer? primitive, host-error alias. Transpiler fixes: match/case routing,
wildcard _ support, nested match arm handling.
2522/2524 OCaml tests pass (2 pre-existing scope failures from transpiler
match codegen, not related to these changes).
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
SX lambdas ((fn (x) body)) now transpile to NativeFn values that can
be stored as SX values — passed to signal-add-sub!, stored in dicts,
used as reactive subscribers. Previously emitted as bare OCaml closures
which couldn't be stored in the SX value type system.
ml-emit-fn → NativeFn("λ", fun args -> match args with [...] -> body)
ml-emit-fn-bare → (fun params -> body) — used by HO inliners and
recursive let bindings (let rec) which call themselves directly.
HO forms (map, filter, reduce, for-each, map-indexed, map-dict) use
cek_call for non-inline function arguments, bare OCaml lambdas for
inline (fn ...) arguments.
Runtime: with_island_scope accepts NativeFn values (pattern match on
value type) since transpiled lambdas are now NativeFn-wrapped.
Unblocks WASM reactive signals — the bootstrap FIXUPS that manually
wrapped reactive_shift_deref's subscriber as NativeFn are no longer
needed when merging to the wasm branch.
1314/1314 JS tests, 4/4 Playwright isomorphic tests.
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
Replace continuation-based scope frames with hashtable stacks for all
scope operations. The CEK evaluator's scope/provide/context/emit!/emitted
now use scope-push!/pop!/peek/emit! primitives (registered in
sx_primitives table) instead of walking continuation frames.
This eliminates the two-world problem where the aser used hashtable
stacks (scope-push!/pop!) but eval-expr used continuation frames
(ScopeFrame/ScopeAccFrame). Now both paths share the same mechanism.
Benefits:
- scope/context works inside eval-expr calls (e.g. (str ... (context x)))
- O(1) scope lookup vs O(n) continuation walking
- Simpler — no ScopeFrame/ScopeAccFrame/ProvideFrame creation/dispatch
- VM-compiled code and CEK code both see the same scope state
Also registers scope-push!/pop!/peek/emit!/collect!/collected/
clear-collected! as real primitives (sx_primitives table) so the
transpiled evaluator can call them directly.
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
Transpiler detects dict literals with a "type" string field and emits
CekFrame records instead of Dict(Hashtbl). Maps frame-specific fields
to generic record slots:
cf_type, cf_env, cf_name, cf_body, cf_remaining, cf_f,
cf_args (also evaled), cf_results (also raw-args),
cf_extra (ho-type/scheme/indexed/match-val/current-item/...),
cf_extra2 (emitted/effect-list/first-render)
Runtime get_val handles CekFrame with direct field match — O(1)
field access vs Hashtbl.find.
Bootstrapper: skip stdlib.sx entirely (already OCaml primitives).
Result: 29 CekFrame + 2 CekState = 31 record types, only 8
Hashtbl.create remaining (effect-annotations, empty dicts).
Benchmark (200 divs): 2.94s → 1.71s (1.7x speedup from baseline).
Real pages: ~same as CekState-only (frames are <20% of allocations;
states dominate at 199K/page).
Foundation for JIT: record-based value representation enables
typed compilation — JIT can emit direct field access instead of
hash table lookups.
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
Transpiler (transpiler.sx): detects CEK state dict literals (5 fields:
control/env/kont/phase/value) and emits CekState OCaml record instead
of Dict(Hashtbl). Eliminates 200K Hashtbl allocations per page.
Bootstrapper: skip stdlib.sx (functions already registered as OCaml
primitives). Only transpile evaluator.sx.
Runtime: get_val handles CekState with direct field access. type_of
returns "dict" for CekState (backward compat).
Profiling results (root cause of slowness):
Pure eval: OCaml 1.6x FASTER than Python (expected)
Aser: OCaml 28x SLOWER than Python (unexpected!)
Root cause: Python has a native optimized aser. OCaml runs the SX
adapter-sx.sx through the CEK machine — each aserCall is ~50 CEK
steps with closures, scope operations, string building.
Fix needed: native OCaml aser (like Python's), not SX adapter
through CEK machine.
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
SX-to-OCaml transpiler (transpiler.sx) generates sx_ref.ml (~90KB, ~135
mutually recursive functions) from the spec evaluator. Foundation tests
all pass: parser, primitives, env operations, type system.
Key design decisions:
- Env variant added to value type for CEK state dict storage
- Continuation carries optional data dict for captured frames
- Dynamic var tracking distinguishes OCaml fn calls from SX value dispatch
- Single let rec...and block for forward references between all defines
- Unused ref pre-declarations eliminated via let-bound name detection
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
