From 6602ec8cc9cd25dc30c6b4f6fbe30a88bc64c10c Mon Sep 17 00:00:00 2001
From: giles <giles.bradshaw@rose-ash.com>
Date: Sun, 26 Apr 2026 15:16:56 +0000
Subject: [PATCH] =?UTF-8?q?ocaml:=20wire=20dynamic-wind=20through=20CEK=20?=
 =?UTF-8?q?=E2=80=94=20WindFrame=20+=20winders=20stack?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

- 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>
---
 hosts/ocaml/lib/sx_ref.ml     | 64 +++++++++++++++++------------------
 hosts/ocaml/lib/sx_runtime.ml | 18 +++++++---
 hosts/ocaml/lib/sx_types.ml   |  8 ++---
 hosts/ocaml/transpiler.sx     | 10 ++++--
 4 files changed, 55 insertions(+), 45 deletions(-)

diff --git a/hosts/ocaml/lib/sx_ref.ml b/hosts/ocaml/lib/sx_ref.ml
index 590ea6de..db75479f 100644
--- a/hosts/ocaml/lib/sx_ref.ml
+++ b/hosts/ocaml/lib/sx_ref.ml
@@ -10,7 +10,7 @@ open Sx_runtime
 let trampoline_fn : (value -> value) ref = ref (fun v -> v)
 let trampoline v = !trampoline_fn v
 
-(* Step limit for timeout protection *)
+(* Step limit for timeout detection — set to 0 to disable *)
 let step_limit : int ref = ref 0
 let step_count : int ref = ref 0
 
@@ -208,6 +208,14 @@ and make_reactive_reset_frame env update_fn first_render_p =
 and make_callcc_frame env =
   (CekFrame { cf_type = "callcc"; cf_env = env; cf_name = Nil; cf_body = Nil; cf_remaining = Nil; cf_f = Nil; cf_args = Nil; cf_results = Nil; cf_extra = Nil; cf_extra2 = Nil })
 
+(* make-wind-after-frame *)
+and make_wind_after_frame after_thunk winders_len env =
+  (CekFrame { cf_type = "wind-after"; cf_env = env; cf_name = Nil; cf_body = Nil; cf_remaining = Nil; cf_f = after_thunk; cf_args = Nil; cf_results = Nil; cf_extra = winders_len; cf_extra2 = Nil })
+
+(* make-wind-return-frame *)
+and make_wind_return_frame body_result env =
+  (CekFrame { cf_type = "wind-return"; cf_env = env; cf_name = body_result; cf_body = Nil; cf_remaining = Nil; cf_f = Nil; cf_args = Nil; cf_results = Nil; cf_extra = Nil; cf_extra2 = Nil })
+
 (* make-deref-frame *)
 and make_deref_frame env =
   (CekFrame { cf_type = "deref"; cf_env = env; cf_name = Nil; cf_body = Nil; cf_remaining = Nil; cf_f = Nil; cf_args = Nil; cf_results = Nil; cf_extra = Nil; cf_extra2 = Nil })
@@ -268,6 +276,14 @@ and find_matching_handler handlers condition =
 and kont_find_handler kont condition =
   (if sx_truthy ((empty_p (kont))) then Nil else (let frame = (first (kont)) in (if sx_truthy ((prim_call "=" [(frame_type (frame)); (String "handler")])) then (let match' = (find_matching_handler ((get (frame) ((String "f")))) (condition)) in (if sx_truthy ((is_nil (match'))) then (kont_find_handler ((rest (kont))) (condition)) else match')) else (kont_find_handler ((rest (kont))) (condition)))))
 
+(* kont-unwind-to-handler *)
+and kont_unwind_to_handler kont condition =
+  (if sx_truthy ((empty_p (kont))) then (let _d = Hashtbl.create 2 in Hashtbl.replace _d "handler" Nil; Hashtbl.replace _d "kont" kont; Dict _d) else (let frame = (first (kont)) in let rest_k = (rest (kont)) in (if sx_truthy ((prim_call "=" [(frame_type (frame)); (String "handler")])) then (let match' = (find_matching_handler ((get (frame) ((String "f")))) (condition)) in (if sx_truthy ((is_nil (match'))) then (kont_unwind_to_handler (rest_k) (condition)) else (let _d = Hashtbl.create 2 in Hashtbl.replace _d "handler" match'; Hashtbl.replace _d "kont" kont; Dict _d))) else (if sx_truthy ((prim_call "=" [(frame_type (frame)); (String "wind-after")])) then (let () = ignore ((if sx_truthy ((prim_call ">" [(len (!_winders_ref)); (get (frame) ((String "winders-len")))])) then (_winders_ref := (rest (!_winders_ref)); Nil) else Nil)) in (let () = ignore ((cek_call ((get (frame) ((String "after-thunk")))) ((List [])))) in (kont_unwind_to_handler (rest_k) (condition)))) else (kont_unwind_to_handler (rest_k) (condition))))))
+
+(* wind-escape-to *)
+and wind_escape_to target_len =
+  (if sx_truthy ((prim_call ">" [(len (!_winders_ref)); target_len])) then (let after_thunk = (first (!_winders_ref)) in (let () = ignore ((_winders_ref := (rest (!_winders_ref)); Nil)) in (let () = ignore ((cek_call (after_thunk) ((List [])))) in (wind_escape_to (target_len))))) else Nil)
+
 (* find-named-restart *)
 and find_named_restart restarts name =
   (if sx_truthy ((empty_p (restarts))) then Nil else (let entry = (first (restarts)) in (if sx_truthy ((prim_call "=" [(first (entry)); name])) then entry else (find_named_restart ((rest (restarts))) (name)))))
@@ -356,6 +372,11 @@ and _provide_subscribers_ref = ref (Dict (Hashtbl.create 0))
 and _provide_subscribers_ =
   (Dict (Hashtbl.create 0))
 
+(* *winders* *)
+and _winders_ref = ref (List [])
+and _winders_ =
+  (List [])
+
 (* *library-registry* *)
 and _library_registry_ =
   (Dict (Hashtbl.create 0))
@@ -558,9 +579,9 @@ and sf_letrec args env =
 and step_sf_letrec args env kont =
   (let thk = (sf_letrec (args) (env)) in (make_cek_state ((thunk_expr (thk))) ((thunk_env (thk))) (kont)))
 
-(* sf-dynamic-wind *)
-and sf_dynamic_wind args env =
-  (let before = (trampoline ((eval_expr ((first (args))) (env)))) in let body = (trampoline ((eval_expr ((nth (args) ((Number 1.0)))) (env)))) in let after = (trampoline ((eval_expr ((nth (args) ((Number 2.0)))) (env)))) in (dynamic_wind_call (before) (body) (after) (env)))
+(* step-sf-dynamic-wind *)
+and step_sf_dynamic_wind args env kont =
+  (let before = (trampoline ((eval_expr ((first (args))) (env)))) in let body = (trampoline ((eval_expr ((nth (args) ((Number 1.0)))) (env)))) in let after = (trampoline ((eval_expr ((nth (args) ((Number 2.0)))) (env)))) in (let () = ignore ((cek_call (before) ((List [])))) in (let winders_len = (len (!_winders_ref)) in (let () = ignore ((_winders_ref := (cons (after) (!_winders_ref)); Nil)) in (continue_with_call (body) ((List [])) (env) ((List [])) ((kont_push ((make_wind_after_frame (after) (winders_len) (env))) (kont))))))))
 
 (* sf-scope *)
 and sf_scope args env =
@@ -576,34 +597,11 @@ and expand_macro mac raw_args env =
 
 (* cek-step-loop *)
 and cek_step_loop state =
-  if !step_limit > 0 then begin
-    step_count := !step_count + 1;
-    if !step_count > !step_limit then
-      raise (Sx_types.Eval_error "TIMEOUT: step limit exceeded")
-  end;
-  (if sx_truthy ((let _or = (cek_terminal_p (state)) in if sx_truthy _or then _or else (cek_suspended_p (state)))) then state else begin
-    let next = (try cek_step (state)
-      with Sx_types.CekPerformRequest request ->
-        make_cek_suspended request (cek_env state) (cek_kont state))
-    in cek_step_loop next
-  end)
+  (if sx_truthy ((let _or = (cek_terminal_p (state)) in if sx_truthy _or then _or else (cek_suspended_p (state)))) then state else (cek_step_loop ((cek_step (state)))))
 
-(* cek-run — with IO suspension hooks for the OCaml host *)
+(* cek-run *)
 and cek_run state =
-  let rec run s =
-    let final = cek_step_loop s in
-    if sx_truthy (cek_suspended_p final) then
-      match !Sx_types._cek_io_resolver with
-      | Some resolver ->
-        let request = cek_io_request final in
-        let result = resolver request final in
-        run (cek_resume final result)
-      | None ->
-        (match !Sx_types._cek_io_suspend_hook with
-         | Some hook -> hook final
-         | None -> raise (Eval_error (value_to_str (String "IO suspension in non-IO context"))))
-    else cek_value final
-  in run state
+  (let final = (cek_step_loop (state)) in (if sx_truthy ((cek_suspended_p (final))) then (raise (Eval_error (value_to_str (String "IO suspension in non-IO context")))) else (cek_value (final))))
 
 (* cek-resume *)
 and cek_resume suspended_state result' =
@@ -639,7 +637,7 @@ and step_sf_let_match args env kont =
 
 (* step-eval-list *)
 and step_eval_list expr env kont =
-  (let head = (first (expr)) in let args = (rest (expr)) in (if sx_truthy ((Bool (not (sx_truthy ((let _or = (prim_call "=" [(type_of (head)); (String "symbol")]) in if sx_truthy _or then _or else (let _or = (prim_call "=" [(type_of (head)); (String "lambda")]) in if sx_truthy _or then _or else (prim_call "=" [(type_of (head)); (String "list")])))))))) then (if sx_truthy ((empty_p (expr))) then (make_cek_value ((List [])) (env) (kont)) else (make_cek_state ((first (expr))) (env) ((kont_push ((make_map_frame (Nil) ((rest (expr))) ((List [])) (env))) (kont))))) else (if sx_truthy ((prim_call "=" [(type_of (head)); (String "symbol")])) then (let name = (symbol_name (head)) in (let _match_val = name in (if sx_truthy ((prim_call "=" [_match_val; (String "if")])) then (step_sf_if (args) (env) (kont)) else (if sx_truthy ((prim_call "=" [_match_val; (String "when")])) then (step_sf_when (args) (env) (kont)) else (if sx_truthy ((prim_call "=" [_match_val; (String "cond")])) then (step_sf_cond (args) (env) (kont)) else (if sx_truthy ((prim_call "=" [_match_val; (String "case")])) then (step_sf_case (args) (env) (kont)) else (if sx_truthy ((prim_call "=" [_match_val; (String "and")])) then (step_sf_and (args) (env) (kont)) else (if sx_truthy ((prim_call "=" [_match_val; (String "or")])) then (step_sf_or (args) (env) (kont)) else (if sx_truthy ((prim_call "=" [_match_val; (String "let")])) then (step_sf_let (args) (env) (kont)) else (if sx_truthy ((prim_call "=" [_match_val; (String "let*")])) then (step_sf_let (args) (env) (kont)) else (if sx_truthy ((prim_call "=" [_match_val; (String "lambda")])) then (step_sf_lambda (args) (env) (kont)) else (if sx_truthy ((prim_call "=" [_match_val; (String "fn")])) then (step_sf_lambda (args) (env) (kont)) else (if sx_truthy ((prim_call "=" [_match_val; (String "define")])) then (step_sf_define (args) (env) (kont)) else (if sx_truthy ((prim_call "=" [_match_val; (String "defcomp")])) then (make_cek_value ((sf_defcomp (args) (env))) (env) (kont)) else (if sx_truthy ((prim_call "=" [_match_val; (String "defisland")])) then (make_cek_value ((sf_defisland (args) (env))) (env) (kont)) else (if sx_truthy ((prim_call "=" [_match_val; (String "defmacro")])) then (make_cek_value ((sf_defmacro (args) (env))) (env) (kont)) else (if sx_truthy ((prim_call "=" [_match_val; (String "defio")])) then (make_cek_value ((sf_defio (args) (env))) (env) (kont)) else (if sx_truthy ((prim_call "=" [_match_val; (String "define-foreign")])) then (step_sf_define_foreign (args) (env) (kont)) else (if sx_truthy ((prim_call "=" [_match_val; (String "io")])) then (step_sf_io (args) (env) (kont)) else (if sx_truthy ((prim_call "=" [_match_val; (String "begin")])) then (step_sf_begin (args) (env) (kont)) else (if sx_truthy ((prim_call "=" [_match_val; (String "do")])) then (if sx_truthy ((let _and = (Bool (not (sx_truthy ((empty_p (args)))))) in if not (sx_truthy _and) then _and else (let _and = (list_p ((first (args)))) in if not (sx_truthy _and) then _and else (let _and = (Bool (not (sx_truthy ((empty_p ((first (args)))))))) in if not (sx_truthy _and) then _and else (list_p ((first ((first (args)))))))))) then (let bindings = (first (args)) in let test_clause = (nth (args) ((Number 1.0))) in let body = (rest ((rest (args)))) in let vars = (List (List.map (fun b -> (first (b))) (sx_to_list bindings))) in let inits = (List (List.map (fun b -> (nth (b) ((Number 1.0)))) (sx_to_list bindings))) in let steps = (List (List.map (fun b -> (if sx_truthy ((prim_call ">" [(len (b)); (Number 2.0)])) then (nth (b) ((Number 2.0))) else (first (b)))) (sx_to_list bindings))) in let test = (first (test_clause)) in let result' = (rest (test_clause)) in (step_eval_list ((cons ((Symbol "let")) ((cons ((Symbol "__do-loop")) ((cons ((List (List.map (fun b -> (List [(first (b)); (nth (b) ((Number 1.0)))])) (sx_to_list bindings)))) ((List [(cons ((Symbol "if")) ((cons (test) ((cons ((if sx_truthy ((empty_p (result'))) then Nil else (cons ((Symbol "begin")) (result')))) ((List [(cons ((Symbol "begin")) ((prim_call "append" [body; (List [(cons ((Symbol "__do-loop")) (steps))])])))])))))))])))))))) (env) (kont))) else (step_sf_begin (args) (env) (kont))) else (if sx_truthy ((prim_call "=" [_match_val; (String "guard")])) then (step_sf_guard (args) (env) (kont)) else (if sx_truthy ((prim_call "=" [_match_val; (String "quote")])) then (make_cek_value ((if sx_truthy ((empty_p (args))) then Nil else (first (args)))) (env) (kont)) else (if sx_truthy ((prim_call "=" [_match_val; (String "quasiquote")])) then (make_cek_value ((qq_expand ((first (args))) (env))) (env) (kont)) else (if sx_truthy ((prim_call "=" [_match_val; (String "->")])) then (step_sf_thread_first (args) (env) (kont)) else (if sx_truthy ((prim_call "=" [_match_val; (String "->>")])) then (step_sf_thread_last (args) (env) (kont)) else (if sx_truthy ((prim_call "=" [_match_val; (String "|>")])) then (step_sf_thread_last (args) (env) (kont)) else (if sx_truthy ((prim_call "=" [_match_val; (String "as->")])) then (step_sf_thread_as (args) (env) (kont)) else (if sx_truthy ((prim_call "=" [_match_val; (String "set!")])) then (step_sf_set_b (args) (env) (kont)) else (if sx_truthy ((prim_call "=" [_match_val; (String "letrec")])) then (step_sf_letrec (args) (env) (kont)) else (if sx_truthy ((prim_call "=" [_match_val; (String "reset")])) then (step_sf_reset (args) (env) (kont)) else (if sx_truthy ((prim_call "=" [_match_val; (String "shift")])) then (step_sf_shift (args) (env) (kont)) else (if sx_truthy ((prim_call "=" [_match_val; (String "deref")])) then (step_sf_deref (args) (env) (kont)) else (if sx_truthy ((prim_call "=" [_match_val; (String "scope")])) then (step_sf_scope (args) (env) (kont)) else (if sx_truthy ((prim_call "=" [_match_val; (String "provide")])) then (step_sf_provide (args) (env) (kont)) else (if sx_truthy ((prim_call "=" [_match_val; (String "peek")])) then (step_sf_peek (args) (env) (kont)) else (if sx_truthy ((prim_call "=" [_match_val; (String "provide!")])) then (step_sf_provide_b (args) (env) (kont)) else (if sx_truthy ((prim_call "=" [_match_val; (String "context")])) then (step_sf_context (args) (env) (kont)) else (if sx_truthy ((prim_call "=" [_match_val; (String "bind")])) then (step_sf_bind (args) (env) (kont)) else (if sx_truthy ((prim_call "=" [_match_val; (String "emit!")])) then (step_sf_emit (args) (env) (kont)) else (if sx_truthy ((prim_call "=" [_match_val; (String "emitted")])) then (step_sf_emitted (args) (env) (kont)) else (if sx_truthy ((prim_call "=" [_match_val; (String "handler-bind")])) then (step_sf_handler_bind (args) (env) (kont)) else (if sx_truthy ((prim_call "=" [_match_val; (String "restart-case")])) then (step_sf_restart_case (args) (env) (kont)) else (if sx_truthy ((prim_call "=" [_match_val; (String "signal-condition")])) then (step_sf_signal (args) (env) (kont)) else (if sx_truthy ((prim_call "=" [_match_val; (String "invoke-restart")])) then (step_sf_invoke_restart (args) (env) (kont)) else (if sx_truthy ((prim_call "=" [_match_val; (String "match")])) then (step_sf_match (args) (env) (kont)) else (if sx_truthy ((prim_call "=" [_match_val; (String "let-match")])) then (step_sf_let_match (args) (env) (kont)) else (if sx_truthy ((prim_call "=" [_match_val; (String "dynamic-wind")])) then (make_cek_value ((sf_dynamic_wind (args) (env))) (env) (kont)) else (if sx_truthy ((prim_call "=" [_match_val; (String "map")])) then (step_ho_map (args) (env) (kont)) else (if sx_truthy ((prim_call "=" [_match_val; (String "map-indexed")])) then (step_ho_map_indexed (args) (env) (kont)) else (if sx_truthy ((prim_call "=" [_match_val; (String "filter")])) then (step_ho_filter (args) (env) (kont)) else (if sx_truthy ((prim_call "=" [_match_val; (String "reduce")])) then (step_ho_reduce (args) (env) (kont)) else (if sx_truthy ((prim_call "=" [_match_val; (String "some")])) then (step_ho_some (args) (env) (kont)) else (if sx_truthy ((prim_call "=" [_match_val; (String "every?")])) then (step_ho_every (args) (env) (kont)) else (if sx_truthy ((prim_call "=" [_match_val; (String "for-each")])) then (step_ho_for_each (args) (env) (kont)) else (if sx_truthy ((prim_call "=" [_match_val; (String "raise")])) then (step_sf_raise (args) (env) (kont)) else (if sx_truthy ((prim_call "=" [_match_val; (String "raise-continuable")])) then (make_cek_state ((first (args))) (env) ((kont_push ((make_raise_eval_frame (env) ((Bool true)))) (kont)))) else (if sx_truthy ((prim_call "=" [_match_val; (String "call/cc")])) then (step_sf_callcc (args) (env) (kont)) else (if sx_truthy ((prim_call "=" [_match_val; (String "call-with-current-continuation")])) then (step_sf_callcc (args) (env) (kont)) else (if sx_truthy ((prim_call "=" [_match_val; (String "perform")])) then (step_sf_perform (args) (env) (kont)) else (if sx_truthy ((prim_call "=" [_match_val; (String "define-library")])) then (step_sf_define_library (args) (env) (kont)) else (if sx_truthy ((prim_call "=" [_match_val; (String "import")])) then (step_sf_import (args) (env) (kont)) else (if sx_truthy ((prim_call "=" [_match_val; (String "define-record-type")])) then (make_cek_value ((sf_define_record_type (args) (env))) (env) (kont)) else (if sx_truthy ((prim_call "=" [_match_val; (String "define-protocol")])) then (make_cek_value ((sf_define_protocol (args) (env))) (env) (kont)) else (if sx_truthy ((prim_call "=" [_match_val; (String "implement")])) then (make_cek_value ((sf_implement (args) (env))) (env) (kont)) else (if sx_truthy ((prim_call "=" [_match_val; (String "parameterize")])) then (step_sf_parameterize (args) (env) (kont)) else (if sx_truthy ((prim_call "=" [_match_val; (String "syntax-rules")])) then (make_cek_value ((sf_syntax_rules (args) (env))) (env) (kont)) else (if sx_truthy ((prim_call "=" [_match_val; (String "define-syntax")])) then (step_sf_define (args) (env) (kont)) else (if sx_truthy ((let _and = (prim_call "has-key?" [custom_special_forms; name]) in if not (sx_truthy _and) then _and else (Bool (not (sx_truthy ((env_has (env) (name)))))))) then (make_cek_value ((cek_call ((get (custom_special_forms) (name))) (List [args; env]))) (env) (kont)) else (if sx_truthy ((let _and = (env_has (env) (name)) in if not (sx_truthy _and) then _and else (is_macro ((env_get (env) (name)))))) then (let mac = (env_get (env) (name)) in (make_cek_state ((expand_macro (mac) (args) (env))) (env) (kont))) else (if sx_truthy ((let _and = render_check in if not (sx_truthy _and) then _and else (let _and = (Bool (not (sx_truthy ((env_has (env) (name)))))) in if not (sx_truthy _and) then _and else (cek_call (render_check) (List [expr; env]))))) then (make_cek_value ((cek_call (render_fn) (List [expr; env]))) (env) (kont)) else (step_eval_call (head) (args) (env) (kont))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))) else (step_eval_call (head) (args) (env) (kont)))))
+  (let head = (first (expr)) in let args = (rest (expr)) in (if sx_truthy ((Bool (not (sx_truthy ((let _or = (prim_call "=" [(type_of (head)); (String "symbol")]) in if sx_truthy _or then _or else (let _or = (prim_call "=" [(type_of (head)); (String "lambda")]) in if sx_truthy _or then _or else (prim_call "=" [(type_of (head)); (String "list")])))))))) then (if sx_truthy ((empty_p (expr))) then (make_cek_value ((List [])) (env) (kont)) else (make_cek_state ((first (expr))) (env) ((kont_push ((make_map_frame (Nil) ((rest (expr))) ((List [])) (env))) (kont))))) else (if sx_truthy ((prim_call "=" [(type_of (head)); (String "symbol")])) then (let name = (symbol_name (head)) in (let _match_val = name in (if sx_truthy ((prim_call "=" [_match_val; (String "if")])) then (step_sf_if (args) (env) (kont)) else (if sx_truthy ((prim_call "=" [_match_val; (String "when")])) then (step_sf_when (args) (env) (kont)) else (if sx_truthy ((prim_call "=" [_match_val; (String "cond")])) then (step_sf_cond (args) (env) (kont)) else (if sx_truthy ((prim_call "=" [_match_val; (String "case")])) then (step_sf_case (args) (env) (kont)) else (if sx_truthy ((prim_call "=" [_match_val; (String "and")])) then (step_sf_and (args) (env) (kont)) else (if sx_truthy ((prim_call "=" [_match_val; (String "or")])) then (step_sf_or (args) (env) (kont)) else (if sx_truthy ((prim_call "=" [_match_val; (String "let")])) then (step_sf_let (args) (env) (kont)) else (if sx_truthy ((prim_call "=" [_match_val; (String "let*")])) then (step_sf_let (args) (env) (kont)) else (if sx_truthy ((prim_call "=" [_match_val; (String "lambda")])) then (step_sf_lambda (args) (env) (kont)) else (if sx_truthy ((prim_call "=" [_match_val; (String "fn")])) then (step_sf_lambda (args) (env) (kont)) else (if sx_truthy ((prim_call "=" [_match_val; (String "define")])) then (step_sf_define (args) (env) (kont)) else (if sx_truthy ((prim_call "=" [_match_val; (String "defcomp")])) then (make_cek_value ((sf_defcomp (args) (env))) (env) (kont)) else (if sx_truthy ((prim_call "=" [_match_val; (String "defisland")])) then (make_cek_value ((sf_defisland (args) (env))) (env) (kont)) else (if sx_truthy ((prim_call "=" [_match_val; (String "defmacro")])) then (make_cek_value ((sf_defmacro (args) (env))) (env) (kont)) else (if sx_truthy ((prim_call "=" [_match_val; (String "defio")])) then (make_cek_value ((sf_defio (args) (env))) (env) (kont)) else (if sx_truthy ((prim_call "=" [_match_val; (String "define-foreign")])) then (step_sf_define_foreign (args) (env) (kont)) else (if sx_truthy ((prim_call "=" [_match_val; (String "io")])) then (step_sf_io (args) (env) (kont)) else (if sx_truthy ((prim_call "=" [_match_val; (String "begin")])) then (step_sf_begin (args) (env) (kont)) else (if sx_truthy ((prim_call "=" [_match_val; (String "do")])) then (if sx_truthy ((let _and = (Bool (not (sx_truthy ((empty_p (args)))))) in if not (sx_truthy _and) then _and else (let _and = (list_p ((first (args)))) in if not (sx_truthy _and) then _and else (let _and = (Bool (not (sx_truthy ((empty_p ((first (args)))))))) in if not (sx_truthy _and) then _and else (list_p ((first ((first (args)))))))))) then (let bindings = (first (args)) in let test_clause = (nth (args) ((Number 1.0))) in let body = (rest ((rest (args)))) in let vars = (List (List.map (fun b -> (first (b))) (sx_to_list bindings))) in let inits = (List (List.map (fun b -> (nth (b) ((Number 1.0)))) (sx_to_list bindings))) in let steps = (List (List.map (fun b -> (if sx_truthy ((prim_call ">" [(len (b)); (Number 2.0)])) then (nth (b) ((Number 2.0))) else (first (b)))) (sx_to_list bindings))) in let test = (first (test_clause)) in let result' = (rest (test_clause)) in (step_eval_list ((cons ((Symbol "let")) ((cons ((Symbol "__do-loop")) ((cons ((List (List.map (fun b -> (List [(first (b)); (nth (b) ((Number 1.0)))])) (sx_to_list bindings)))) ((List [(cons ((Symbol "if")) ((cons (test) ((cons ((if sx_truthy ((empty_p (result'))) then Nil else (cons ((Symbol "begin")) (result')))) ((List [(cons ((Symbol "begin")) ((prim_call "append" [body; (List [(cons ((Symbol "__do-loop")) (steps))])])))])))))))])))))))) (env) (kont))) else (step_sf_begin (args) (env) (kont))) else (if sx_truthy ((prim_call "=" [_match_val; (String "guard")])) then (step_sf_guard (args) (env) (kont)) else (if sx_truthy ((prim_call "=" [_match_val; (String "quote")])) then (make_cek_value ((if sx_truthy ((empty_p (args))) then Nil else (first (args)))) (env) (kont)) else (if sx_truthy ((prim_call "=" [_match_val; (String "quasiquote")])) then (make_cek_value ((qq_expand ((first (args))) (env))) (env) (kont)) else (if sx_truthy ((prim_call "=" [_match_val; (String "->")])) then (step_sf_thread_first (args) (env) (kont)) else (if sx_truthy ((prim_call "=" [_match_val; (String "->>")])) then (step_sf_thread_last (args) (env) (kont)) else (if sx_truthy ((prim_call "=" [_match_val; (String "|>")])) then (step_sf_thread_last (args) (env) (kont)) else (if sx_truthy ((prim_call "=" [_match_val; (String "as->")])) then (step_sf_thread_as (args) (env) (kont)) else (if sx_truthy ((prim_call "=" [_match_val; (String "set!")])) then (step_sf_set_b (args) (env) (kont)) else (if sx_truthy ((prim_call "=" [_match_val; (String "letrec")])) then (step_sf_letrec (args) (env) (kont)) else (if sx_truthy ((prim_call "=" [_match_val; (String "reset")])) then (step_sf_reset (args) (env) (kont)) else (if sx_truthy ((prim_call "=" [_match_val; (String "shift")])) then (step_sf_shift (args) (env) (kont)) else (if sx_truthy ((prim_call "=" [_match_val; (String "deref")])) then (step_sf_deref (args) (env) (kont)) else (if sx_truthy ((prim_call "=" [_match_val; (String "scope")])) then (step_sf_scope (args) (env) (kont)) else (if sx_truthy ((prim_call "=" [_match_val; (String "provide")])) then (step_sf_provide (args) (env) (kont)) else (if sx_truthy ((prim_call "=" [_match_val; (String "peek")])) then (step_sf_peek (args) (env) (kont)) else (if sx_truthy ((prim_call "=" [_match_val; (String "provide!")])) then (step_sf_provide_b (args) (env) (kont)) else (if sx_truthy ((prim_call "=" [_match_val; (String "context")])) then (step_sf_context (args) (env) (kont)) else (if sx_truthy ((prim_call "=" [_match_val; (String "bind")])) then (step_sf_bind (args) (env) (kont)) else (if sx_truthy ((prim_call "=" [_match_val; (String "emit!")])) then (step_sf_emit (args) (env) (kont)) else (if sx_truthy ((prim_call "=" [_match_val; (String "emitted")])) then (step_sf_emitted (args) (env) (kont)) else (if sx_truthy ((prim_call "=" [_match_val; (String "handler-bind")])) then (step_sf_handler_bind (args) (env) (kont)) else (if sx_truthy ((prim_call "=" [_match_val; (String "restart-case")])) then (step_sf_restart_case (args) (env) (kont)) else (if sx_truthy ((prim_call "=" [_match_val; (String "signal-condition")])) then (step_sf_signal (args) (env) (kont)) else (if sx_truthy ((prim_call "=" [_match_val; (String "invoke-restart")])) then (step_sf_invoke_restart (args) (env) (kont)) else (if sx_truthy ((prim_call "=" [_match_val; (String "match")])) then (step_sf_match (args) (env) (kont)) else (if sx_truthy ((prim_call "=" [_match_val; (String "let-match")])) then (step_sf_let_match (args) (env) (kont)) else (if sx_truthy ((prim_call "=" [_match_val; (String "dynamic-wind")])) then (step_sf_dynamic_wind (args) (env) (kont)) else (if sx_truthy ((prim_call "=" [_match_val; (String "map")])) then (step_ho_map (args) (env) (kont)) else (if sx_truthy ((prim_call "=" [_match_val; (String "map-indexed")])) then (step_ho_map_indexed (args) (env) (kont)) else (if sx_truthy ((prim_call "=" [_match_val; (String "filter")])) then (step_ho_filter (args) (env) (kont)) else (if sx_truthy ((prim_call "=" [_match_val; (String "reduce")])) then (step_ho_reduce (args) (env) (kont)) else (if sx_truthy ((prim_call "=" [_match_val; (String "some")])) then (step_ho_some (args) (env) (kont)) else (if sx_truthy ((prim_call "=" [_match_val; (String "every?")])) then (step_ho_every (args) (env) (kont)) else (if sx_truthy ((prim_call "=" [_match_val; (String "for-each")])) then (step_ho_for_each (args) (env) (kont)) else (if sx_truthy ((prim_call "=" [_match_val; (String "raise")])) then (step_sf_raise (args) (env) (kont)) else (if sx_truthy ((prim_call "=" [_match_val; (String "raise-continuable")])) then (make_cek_state ((first (args))) (env) ((kont_push ((make_raise_eval_frame (env) ((Bool true)))) (kont)))) else (if sx_truthy ((prim_call "=" [_match_val; (String "call/cc")])) then (step_sf_callcc (args) (env) (kont)) else (if sx_truthy ((prim_call "=" [_match_val; (String "call-with-current-continuation")])) then (step_sf_callcc (args) (env) (kont)) else (if sx_truthy ((prim_call "=" [_match_val; (String "perform")])) then (step_sf_perform (args) (env) (kont)) else (if sx_truthy ((prim_call "=" [_match_val; (String "define-library")])) then (step_sf_define_library (args) (env) (kont)) else (if sx_truthy ((prim_call "=" [_match_val; (String "import")])) then (step_sf_import (args) (env) (kont)) else (if sx_truthy ((prim_call "=" [_match_val; (String "define-record-type")])) then (make_cek_value ((sf_define_record_type (args) (env))) (env) (kont)) else (if sx_truthy ((prim_call "=" [_match_val; (String "define-protocol")])) then (make_cek_value ((sf_define_protocol (args) (env))) (env) (kont)) else (if sx_truthy ((prim_call "=" [_match_val; (String "implement")])) then (make_cek_value ((sf_implement (args) (env))) (env) (kont)) else (if sx_truthy ((prim_call "=" [_match_val; (String "parameterize")])) then (step_sf_parameterize (args) (env) (kont)) else (if sx_truthy ((prim_call "=" [_match_val; (String "syntax-rules")])) then (make_cek_value ((sf_syntax_rules (args) (env))) (env) (kont)) else (if sx_truthy ((prim_call "=" [_match_val; (String "define-syntax")])) then (step_sf_define (args) (env) (kont)) else (if sx_truthy ((let _and = (prim_call "has-key?" [custom_special_forms; name]) in if not (sx_truthy _and) then _and else (Bool (not (sx_truthy ((env_has (env) (name)))))))) then (make_cek_value ((cek_call ((get (custom_special_forms) (name))) (List [args; env]))) (env) (kont)) else (if sx_truthy ((let _and = (env_has (env) (name)) in if not (sx_truthy _and) then _and else (is_macro ((env_get (env) (name)))))) then (let mac = (env_get (env) (name)) in (make_cek_state ((expand_macro (mac) (args) (env))) (env) (kont))) else (if sx_truthy ((let _and = render_check in if not (sx_truthy _and) then _and else (let _and = (Bool (not (sx_truthy ((env_has (env) (name)))))) in if not (sx_truthy _and) then _and else (cek_call (render_check) (List [expr; env]))))) then (make_cek_value ((cek_call (render_fn) (List [expr; env]))) (env) (kont)) else (step_eval_call (head) (args) (env) (kont))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))) else (step_eval_call (head) (args) (env) (kont)))))
 
 (* kont-extract-provides *)
 and kont_extract_provides kont =
@@ -916,11 +914,11 @@ and step_ho_for_each args env kont =
 
 (* step-continue *)
 and step_continue state =
-  (let value = (cek_value (state)) in let env = (cek_env (state)) in let kont = (cek_kont (state)) in (if sx_truthy ((kont_empty_p (kont))) then state else (let frame = (kont_top (kont)) in let rest_k = (kont_pop (kont)) in let ft = (frame_type (frame)) in (let _match_val = ft in (if sx_truthy ((prim_call "=" [_match_val; (String "if")])) then (if sx_truthy ((let _and = value in if not (sx_truthy _and) then _and else (Bool (not (sx_truthy ((is_nil (value)))))))) then (make_cek_state ((get (frame) ((String "then")))) ((get (frame) ((String "env")))) (rest_k)) else (if sx_truthy ((is_nil ((get (frame) ((String "else")))))) then (make_cek_value (Nil) (env) (rest_k)) else (make_cek_state ((get (frame) ((String "else")))) ((get (frame) ((String "env")))) (rest_k)))) else (if sx_truthy ((prim_call "=" [_match_val; (String "when")])) then (if sx_truthy ((let _and = value in if not (sx_truthy _and) then _and else (Bool (not (sx_truthy ((is_nil (value)))))))) then (let body = (get (frame) ((String "body"))) in let fenv = (get (frame) ((String "env"))) in (if sx_truthy ((empty_p (body))) then (make_cek_value (Nil) (fenv) (rest_k)) else (if sx_truthy ((prim_call "=" [(len (body)); (Number 1.0)])) then (make_cek_state ((first (body))) (fenv) (rest_k)) else (make_cek_state ((first (body))) (fenv) ((kont_push ((make_begin_frame ((rest (body))) (fenv))) (rest_k))))))) else (make_cek_value (Nil) (env) (rest_k))) else (if sx_truthy ((prim_call "=" [_match_val; (String "begin")])) then (let remaining = (get (frame) ((String "remaining"))) in let fenv = (get (frame) ((String "env"))) in (if sx_truthy ((empty_p (remaining))) then (make_cek_value (value) (fenv) (rest_k)) else (if sx_truthy ((prim_call "=" [(len (remaining)); (Number 1.0)])) then (make_cek_state ((first (remaining))) (fenv) (rest_k)) else (make_cek_state ((first (remaining))) (fenv) ((kont_push ((make_begin_frame ((rest (remaining))) (fenv))) (rest_k))))))) else (if sx_truthy ((prim_call "=" [_match_val; (String "let")])) then (let name = (get (frame) ((String "name"))) in let remaining = (get (frame) ((String "remaining"))) in let body = (get (frame) ((String "body"))) in let local = (get (frame) ((String "env"))) in (let () = ignore ((env_bind local (sx_to_string name) value)) in (if sx_truthy ((empty_p (remaining))) then (step_sf_begin (body) (local) (rest_k)) else (let next_binding = (first (remaining)) in let vname = (if sx_truthy ((prim_call "=" [(type_of ((first (next_binding)))); (String "symbol")])) then (symbol_name ((first (next_binding)))) else (first (next_binding))) in (make_cek_state ((nth (next_binding) ((Number 1.0)))) (local) ((kont_push ((make_let_frame (vname) ((rest (remaining))) (body) (local))) (rest_k)))))))) else (if sx_truthy ((prim_call "=" [_match_val; (String "define")])) then (let name = (get (frame) ((String "name"))) in let fenv = (get (frame) ((String "env"))) in let has_effects = (get (frame) ((String "has-effects"))) in let effect_list = (get (frame) ((String "effect-list"))) in (let () = ignore ((if sx_truthy ((let _and = (is_lambda (value)) in if not (sx_truthy _and) then _and else (is_nil ((lambda_name (value)))))) then (set_lambda_name value (sx_to_string name)) else Nil)) in (let () = ignore ((env_bind fenv (sx_to_string name) value)) in (let () = ignore ((if sx_truthy (has_effects) then (let effect_names = (List (List.map (fun e -> (if sx_truthy ((prim_call "=" [(type_of (e)); (String "symbol")])) then (symbol_name (e)) else e)) (sx_to_list effect_list))) in let effect_anns = (if sx_truthy ((env_has (fenv) ((String "*effect-annotations*")))) then (env_get (fenv) ((String "*effect-annotations*"))) else (Dict (Hashtbl.create 0))) in (let () = ignore ((sx_dict_set_b effect_anns name effect_names)) in (env_bind fenv (sx_to_string (String "*effect-annotations*")) effect_anns))) else Nil)) in (make_cek_value (value) (fenv) (rest_k)))))) else (if sx_truthy ((prim_call "=" [_match_val; (String "define-foreign")])) then (let name = (get (frame) ((String "name"))) in let fenv = (get (frame) ((String "env"))) in (let () = ignore ((if sx_truthy ((let _and = (is_lambda (value)) in if not (sx_truthy _and) then _and else (is_nil ((lambda_name (value)))))) then (set_lambda_name value (sx_to_string name)) else Nil)) in (let () = ignore ((env_bind fenv (sx_to_string name) value)) in (make_cek_value (value) (fenv) (rest_k))))) else (if sx_truthy ((prim_call "=" [_match_val; (String "set")])) then (let name = (get (frame) ((String "name"))) in let fenv = (get (frame) ((String "env"))) in (let () = ignore ((env_set fenv (sx_to_string name) value)) in (make_cek_value (value) (env) (rest_k)))) else (if sx_truthy ((prim_call "=" [_match_val; (String "and")])) then (if sx_truthy ((Bool (not (sx_truthy (value))))) then (make_cek_value (value) (env) (rest_k)) else (let remaining = (get (frame) ((String "remaining"))) in (if sx_truthy ((empty_p (remaining))) then (make_cek_value (value) (env) (rest_k)) else (make_cek_state ((first (remaining))) ((get (frame) ((String "env")))) ((if sx_truthy ((prim_call "=" [(len (remaining)); (Number 1.0)])) then rest_k else (kont_push ((make_and_frame ((rest (remaining))) ((get (frame) ((String "env")))))) (rest_k)))))))) else (if sx_truthy ((prim_call "=" [_match_val; (String "or")])) then (if sx_truthy (value) then (make_cek_value (value) (env) (rest_k)) else (let remaining = (get (frame) ((String "remaining"))) in (if sx_truthy ((empty_p (remaining))) then (make_cek_value ((Bool false)) (env) (rest_k)) else (make_cek_state ((first (remaining))) ((get (frame) ((String "env")))) ((if sx_truthy ((prim_call "=" [(len (remaining)); (Number 1.0)])) then rest_k else (kont_push ((make_or_frame ((rest (remaining))) ((get (frame) ((String "env")))))) (rest_k)))))))) else (if sx_truthy ((prim_call "=" [_match_val; (String "cond")])) then (let remaining = (get (frame) ((String "remaining"))) in let fenv = (get (frame) ((String "env"))) in let scheme_p = (get (frame) ((String "scheme"))) in (if sx_truthy (scheme_p) then (if sx_truthy (value) then (let clause = (first (remaining)) in (if sx_truthy ((let _and = (prim_call ">" [(len (clause)); (Number 2.0)]) in if not (sx_truthy _and) then _and else (let _and = (prim_call "=" [(type_of ((nth (clause) ((Number 1.0))))); (String "symbol")]) in if not (sx_truthy _and) then _and else (prim_call "=" [(symbol_name ((nth (clause) ((Number 1.0))))); (String "=>")])))) then (make_cek_state ((nth (clause) ((Number 2.0)))) (fenv) ((kont_push ((make_cond_arrow_frame (value) (fenv))) (rest_k)))) else (make_cek_state ((nth (clause) ((Number 1.0)))) (fenv) (rest_k)))) else (let next_clauses = (rest (remaining)) in (if sx_truthy ((empty_p (next_clauses))) then (make_cek_value (Nil) (fenv) (rest_k)) else (let next_clause = (first (next_clauses)) in let next_test = (first (next_clause)) in (if sx_truthy ((is_else_clause (next_test))) then (make_cek_state ((nth (next_clause) ((Number 1.0)))) (fenv) (rest_k)) else (make_cek_state (next_test) (fenv) ((kont_push ((make_cond_frame (next_clauses) (fenv) ((Bool true)))) (rest_k))))))))) else (if sx_truthy (value) then (make_cek_state ((nth (remaining) ((Number 1.0)))) (fenv) (rest_k)) else (let next = (prim_call "slice" [remaining; (Number 2.0); (len (remaining))]) in (if sx_truthy ((prim_call "<" [(len (next)); (Number 2.0)])) then (make_cek_value (Nil) (fenv) (rest_k)) else (let next_test = (first (next)) in (if sx_truthy ((is_else_clause (next_test))) then (make_cek_state ((nth (next) ((Number 1.0)))) (fenv) (rest_k)) else (make_cek_state (next_test) (fenv) ((kont_push ((make_cond_frame (next) (fenv) ((Bool false)))) (rest_k))))))))))) else (if sx_truthy ((prim_call "=" [_match_val; (String "case")])) then (let match_val = (get (frame) ((String "match-val"))) in let remaining = (get (frame) ((String "remaining"))) in let fenv = (get (frame) ((String "env"))) in (if sx_truthy ((is_nil (match_val))) then (sf_case_step_loop (value) (remaining) (fenv) (rest_k)) else (sf_case_step_loop (match_val) (remaining) (fenv) (rest_k)))) else (if sx_truthy ((prim_call "=" [_match_val; (String "thread")])) then (let remaining = (get (frame) ((String "remaining"))) in let fenv = (get (frame) ((String "env"))) in let mode = (get (frame) ((String "extra"))) in let bind_name = (get (frame) ((String "name"))) in (if sx_truthy ((empty_p (remaining))) then (make_cek_value (value) (fenv) (rest_k)) else (let form = (first (remaining)) in let rest_forms = (rest (remaining)) in let new_kont = (if sx_truthy ((empty_p ((rest (remaining))))) then rest_k else (kont_push ((make_thread_frame ((rest (remaining))) (fenv) (mode) (bind_name))) (rest_k))) in (if sx_truthy ((prim_call "=" [mode; (String "as")])) then (let new_env = (env_extend (fenv)) in (let () = ignore ((env_bind new_env (sx_to_string (symbol_name (bind_name))) value)) in (make_cek_state (form) (new_env) (new_kont)))) else (if sx_truthy ((let _and = (prim_call "=" [(type_of (form)); (String "list")]) in if not (sx_truthy _and) then _and else (let _and = (Bool (not (sx_truthy ((empty_p (form)))))) in if not (sx_truthy _and) then _and else (let _and = (prim_call "=" [(type_of ((first (form)))); (String "symbol")]) in if not (sx_truthy _and) then _and else (ho_form_name_p ((symbol_name ((first (form)))))))))) then (make_cek_state ((cons ((first (form))) ((cons ((List [(Symbol "quote"); value])) ((rest (form))))))) (fenv) (new_kont)) else (if sx_truthy ((prim_call "=" [mode; (String "last")])) then (let result' = (thread_insert_arg_last (form) (value) (fenv)) in (if sx_truthy ((empty_p (rest_forms))) then (make_cek_value (result') (fenv) (rest_k)) else (make_cek_value (result') (fenv) ((kont_push ((make_thread_frame (rest_forms) (fenv) (mode) (bind_name))) (rest_k)))))) else (let result' = (thread_insert_arg (form) (value) (fenv)) in (if sx_truthy ((empty_p (rest_forms))) then (make_cek_value (result') (fenv) (rest_k)) else (make_cek_value (result') (fenv) ((kont_push ((make_thread_frame (rest_forms) (fenv) (mode) (bind_name))) (rest_k)))))))))))) else (if sx_truthy ((prim_call "=" [_match_val; (String "arg")])) then (let f = (get (frame) ((String "f"))) in let evaled = (get (frame) ((String "evaled"))) in let remaining = (get (frame) ((String "remaining"))) in let fenv = (get (frame) ((String "env"))) in let raw_args = (get (frame) ((String "raw-args"))) in let hname = (get (frame) ((String "head-name"))) in (if sx_truthy ((is_nil (f))) then (let () = ignore ((if sx_truthy ((let _and = !_strict_ref in if not (sx_truthy _and) then _and else hname)) then (strict_check_args (hname) ((List []))) else Nil)) in (if sx_truthy ((empty_p (remaining))) then (continue_with_call (value) ((List [])) (fenv) (raw_args) (rest_k)) else (make_cek_state ((first (remaining))) (fenv) ((kont_push ((make_arg_frame (value) ((List [])) ((rest (remaining))) (fenv) (raw_args) (hname))) (rest_k)))))) else (let new_evaled = (prim_call "append" [evaled; (List [value])]) in (if sx_truthy ((empty_p (remaining))) then (let () = ignore ((if sx_truthy ((let _and = !_strict_ref in if not (sx_truthy _and) then _and else hname)) then (strict_check_args (hname) (new_evaled)) else Nil)) in (continue_with_call (f) (new_evaled) (fenv) (raw_args) (rest_k))) else (make_cek_state ((first (remaining))) (fenv) ((kont_push ((make_arg_frame (f) (new_evaled) ((rest (remaining))) (fenv) (raw_args) (hname))) (rest_k)))))))) else (if sx_truthy ((prim_call "=" [_match_val; (String "dict")])) then (let remaining = (get (frame) ((String "remaining"))) in let results = (get (frame) ((String "results"))) in let fenv = (get (frame) ((String "env"))) in (let last_result = (last (results)) in let completed = (prim_call "append" [(prim_call "slice" [results; (Number 0.0); (prim_call "dec" [(len (results))])]); (List [(List [(first (last_result)); value])])]) in (if sx_truthy ((empty_p (remaining))) then (let d = (Dict (Hashtbl.create 0)) in (let () = ignore ((List.iter (fun pair -> ignore ((sx_dict_set_b d (first (pair)) (nth (pair) ((Number 1.0)))))) (sx_to_list completed); Nil)) in (make_cek_value (d) (fenv) (rest_k)))) else (let next_entry = (first (remaining)) in (make_cek_state ((nth (next_entry) ((Number 1.0)))) (fenv) ((kont_push ((make_dict_frame ((rest (remaining))) ((prim_call "append" [completed; (List [(List [(first (next_entry))])])])) (fenv))) (rest_k)))))))) else (if sx_truthy ((prim_call "=" [_match_val; (String "ho-setup")])) then (let ho_type = (get (frame) ((String "ho-type"))) in let remaining = (get (frame) ((String "remaining"))) in let evaled = (prim_call "append" [(get (frame) ((String "evaled"))); (List [value])]) in let fenv = (get (frame) ((String "env"))) in (if sx_truthy ((empty_p (remaining))) then (ho_setup_dispatch (ho_type) (evaled) (fenv) (rest_k)) else (make_cek_state ((first (remaining))) (fenv) ((kont_push ((make_ho_setup_frame (ho_type) ((rest (remaining))) (evaled) (fenv))) (rest_k)))))) else (if sx_truthy ((prim_call "=" [_match_val; (String "reset")])) then (make_cek_value (value) (env) (rest_k)) else (if sx_truthy ((prim_call "=" [_match_val; (String "deref")])) then (let val' = value in let fenv = (get (frame) ((String "env"))) in (if sx_truthy ((Bool (not (sx_truthy ((is_signal (val'))))))) then (make_cek_value (val') (fenv) (rest_k)) else (if sx_truthy ((has_reactive_reset_frame_p (rest_k))) then (reactive_shift_deref (val') (fenv) (rest_k)) else (let () = ignore ((let ctx = (sx_context ((String "sx-reactive")) (Nil)) in (if sx_truthy (ctx) then (let dep_list = ref ((get (ctx) ((String "deps")))) in let notify_fn = (get (ctx) ((String "notify"))) in (if sx_truthy ((Bool (not (sx_truthy ((prim_call "contains?" [!dep_list; val'])))))) then (let () = ignore ((dep_list := sx_append_b !dep_list val'; Nil)) in (signal_add_sub_b (val') (notify_fn))) else Nil)) else Nil))) in (make_cek_value ((signal_value (val'))) (fenv) (rest_k)))))) else (if sx_truthy ((prim_call "=" [_match_val; (String "reactive-reset")])) then (let update_fn = (get (frame) ((String "update-fn"))) in let first_p = (get (frame) ((String "first-render"))) in (let () = ignore ((if sx_truthy ((let _and = update_fn in if not (sx_truthy _and) then _and else (Bool (not (sx_truthy (first_p)))))) then (cek_call (update_fn) ((List [value]))) else Nil)) in (make_cek_value (value) (env) (rest_k)))) else (if sx_truthy ((prim_call "=" [_match_val; (String "scope")])) then (let name = (get (frame) ((String "name"))) in let remaining = (get (frame) ((String "remaining"))) in let fenv = (get (frame) ((String "env"))) in (if sx_truthy ((empty_p (remaining))) then (let () = ignore ((scope_pop (name))) in (make_cek_value (value) (fenv) (rest_k))) else (make_cek_state ((first (remaining))) (fenv) ((kont_push ((make_scope_frame (name) ((rest (remaining))) (fenv))) (rest_k)))))) else (if sx_truthy ((prim_call "=" [_match_val; (String "provide")])) then (let remaining = (get (frame) ((String "remaining"))) in let fenv = (get (frame) ((String "env"))) in (if sx_truthy ((empty_p (remaining))) then (let () = ignore ((scope_pop ((get (frame) ((String "name")))))) in (make_cek_value (value) (fenv) (rest_k))) else (let new_frame = (make_provide_frame ((get (frame) ((String "name")))) ((get (frame) ((String "value")))) ((rest (remaining))) (fenv)) in (let () = ignore ((sx_dict_set_b new_frame (String "subscribers") (get (frame) ((String "subscribers"))))) in (make_cek_state ((first (remaining))) (fenv) ((kont_push (new_frame) (rest_k)))))))) else (if sx_truthy ((prim_call "=" [_match_val; (String "bind")])) then (let tracked = !_bind_tracking_ref in let body = (get (frame) ((String "body"))) in let fenv = (get (frame) ((String "env"))) in let prev = (get (frame) ((String "prev-tracking"))) in (let () = ignore ((_bind_tracking_ref := prev; Nil)) in (let () = ignore ((let subscriber = (NativeFn ("\206\187", fun _args -> match _args with [fire_kont] -> (fun fire_kont -> (cek_run ((make_cek_state (body) (fenv) ((List [])))))) fire_kont | _ -> Nil)) in (List.iter (fun name -> ignore ((let existing = (get (!_provide_subscribers_ref) (name)) in (sx_dict_set_b !_provide_subscribers_ref name (prim_call "append" [(if sx_truthy (existing) then existing else (List [])); (List [subscriber])]))))) (sx_to_list tracked); Nil))) in (make_cek_value (value) (fenv) (rest_k))))) else (if sx_truthy ((prim_call "=" [_match_val; (String "provide-set")])) then (let name = (get (frame) ((String "name"))) in let fenv = (get (frame) ((String "env"))) in let target = (kont_find_provide (rest_k) (name)) in (let old_val = (if sx_truthy (target) then (get (target) ((String "value"))) else (scope_peek (name))) in (let () = ignore ((if sx_truthy (target) then (sx_dict_set_b target (String "value") value) else Nil)) in (let () = ignore ((scope_pop (name))) in (let () = ignore ((scope_push (name) (value))) in (let () = ignore ((if sx_truthy ((Bool (not (sx_truthy ((prim_call "=" [old_val; value])))))) then (fire_provide_subscribers (name)) else Nil)) in (make_cek_value (value) (fenv) (rest_k)))))))) else (if sx_truthy ((prim_call "=" [_match_val; (String "scope-acc")])) then (let remaining = (get (frame) ((String "remaining"))) in let fenv = (get (frame) ((String "env"))) in (if sx_truthy ((empty_p (remaining))) then (make_cek_value (value) (fenv) (rest_k)) else (make_cek_state ((first (remaining))) (fenv) ((kont_push ((let new_frame = (make_scope_acc_frame ((get (frame) ((String "name")))) ((get (frame) ((String "value")))) ((rest (remaining))) (fenv)) in (let () = ignore ((sx_dict_set_b new_frame (String "emitted") (get (frame) ((String "emitted"))))) in new_frame))) (rest_k)))))) else (if sx_truthy ((prim_call "=" [_match_val; (String "map")])) then (let f = (get (frame) ((String "f"))) in let remaining = (get (frame) ((String "remaining"))) in let results = (get (frame) ((String "results"))) in let indexed = (get (frame) ((String "indexed"))) in let fenv = (get (frame) ((String "env"))) in (let new_results = (prim_call "append" [results; (List [value])]) in (if sx_truthy ((empty_p (remaining))) then (make_cek_value (new_results) (fenv) (rest_k)) else (let call_args = (if sx_truthy (indexed) then (List [(len (new_results)); (first (remaining))]) else (List [(first (remaining))])) in let next_frame = (if sx_truthy (indexed) then (make_map_indexed_frame (f) ((rest (remaining))) (new_results) (fenv)) else (make_map_frame (f) ((rest (remaining))) (new_results) (fenv))) in (continue_with_call (f) (call_args) (fenv) ((List [])) ((kont_push (next_frame) (rest_k)))))))) else (if sx_truthy ((prim_call "=" [_match_val; (String "filter")])) then (let f = (get (frame) ((String "f"))) in let remaining = (get (frame) ((String "remaining"))) in let results = (get (frame) ((String "results"))) in let current_item = (get (frame) ((String "current-item"))) in let fenv = (get (frame) ((String "env"))) in (let new_results = (if sx_truthy (value) then (prim_call "append" [results; (List [current_item])]) else results) in (if sx_truthy ((empty_p (remaining))) then (make_cek_value (new_results) (fenv) (rest_k)) else (continue_with_call (f) ((List [(first (remaining))])) (fenv) ((List [])) ((kont_push ((make_filter_frame (f) ((rest (remaining))) (new_results) ((first (remaining))) (fenv))) (rest_k))))))) else (if sx_truthy ((prim_call "=" [_match_val; (String "reduce")])) then (let f = (get (frame) ((String "f"))) in let remaining = (get (frame) ((String "remaining"))) in let fenv = (get (frame) ((String "env"))) in (if sx_truthy ((empty_p (remaining))) then (make_cek_value (value) (fenv) (rest_k)) else (continue_with_call (f) ((List [value; (first (remaining))])) (fenv) ((List [])) ((kont_push ((make_reduce_frame (f) ((rest (remaining))) (fenv))) (rest_k)))))) else (if sx_truthy ((prim_call "=" [_match_val; (String "for-each")])) then (let f = (get (frame) ((String "f"))) in let remaining = (get (frame) ((String "remaining"))) in let fenv = (get (frame) ((String "env"))) in (if sx_truthy ((empty_p (remaining))) then (make_cek_value (Nil) (fenv) (rest_k)) else (continue_with_call (f) ((List [(first (remaining))])) (fenv) ((List [])) ((kont_push ((make_for_each_frame (f) ((rest (remaining))) (fenv))) (rest_k)))))) else (if sx_truthy ((prim_call "=" [_match_val; (String "some")])) then (let f = (get (frame) ((String "f"))) in let remaining = (get (frame) ((String "remaining"))) in let fenv = (get (frame) ((String "env"))) in (if sx_truthy (value) then (make_cek_value (value) (fenv) (rest_k)) else (if sx_truthy ((empty_p (remaining))) then (make_cek_value ((Bool false)) (fenv) (rest_k)) else (continue_with_call (f) ((List [(first (remaining))])) (fenv) ((List [])) ((kont_push ((make_some_frame (f) ((rest (remaining))) (fenv))) (rest_k))))))) else (if sx_truthy ((prim_call "=" [_match_val; (String "every")])) then (let f = (get (frame) ((String "f"))) in let remaining = (get (frame) ((String "remaining"))) in let fenv = (get (frame) ((String "env"))) in (if sx_truthy ((Bool (not (sx_truthy (value))))) then (make_cek_value ((Bool false)) (fenv) (rest_k)) else (if sx_truthy ((empty_p (remaining))) then (make_cek_value ((Bool true)) (fenv) (rest_k)) else (continue_with_call (f) ((List [(first (remaining))])) (fenv) ((List [])) ((kont_push ((make_every_frame (f) ((rest (remaining))) (fenv))) (rest_k))))))) else (if sx_truthy ((prim_call "=" [_match_val; (String "handler")])) then (let remaining = (get (frame) ((String "remaining"))) in let fenv = (get (frame) ((String "env"))) in (if sx_truthy ((empty_p (remaining))) then (make_cek_value (value) (fenv) (rest_k)) else (make_cek_state ((first (remaining))) (fenv) ((kont_push ((make_handler_frame ((get (frame) ((String "f")))) ((rest (remaining))) (fenv))) (rest_k)))))) else (if sx_truthy ((prim_call "=" [_match_val; (String "restart")])) then (make_cek_value (value) (env) (rest_k)) else (if sx_truthy ((prim_call "=" [_match_val; (String "signal-return")])) then (let saved_kont = (get (frame) ((String "saved-kont"))) in (make_cek_value (value) ((get (frame) ((String "env")))) (saved_kont))) else (if sx_truthy ((prim_call "=" [_match_val; (String "comp-trace")])) then (make_cek_value (value) (env) (rest_k)) else (if sx_truthy ((prim_call "=" [_match_val; (String "cond-arrow")])) then (let test_value = (get (frame) ((String "match-val"))) in let fenv = (get (frame) ((String "env"))) in (continue_with_call (value) ((List [test_value])) (fenv) ((List [test_value])) (rest_k))) else (if sx_truthy ((prim_call "=" [_match_val; (String "raise-eval")])) then (let condition = value in let fenv = (get (frame) ((String "env"))) in let continuable_p = (get (frame) ((String "scheme"))) in let handler_fn = (kont_find_handler (rest_k) (condition)) in (if sx_truthy ((is_nil (handler_fn))) then (let () = ignore ((_last_error_kont_ref := rest_k; Nil)) in (host_error ((String (sx_str [(String "Unhandled exception: "); (inspect (condition))]))))) else (continue_with_call (handler_fn) ((List [condition])) (fenv) ((List [condition])) ((if sx_truthy (continuable_p) then (kont_push ((make_signal_return_frame (fenv) (rest_k))) (rest_k)) else (kont_push ((make_raise_guard_frame (fenv) (rest_k))) (rest_k))))))) else (if sx_truthy ((prim_call "=" [_match_val; (String "raise-guard")])) then (let () = ignore ((_last_error_kont_ref := rest_k; Nil)) in (host_error ((String "exception handler returned from non-continuable raise")))) else (if sx_truthy ((prim_call "=" [_match_val; (String "multi-map")])) then (let f = (get (frame) ((String "f"))) in let remaining = (get (frame) ((String "remaining"))) in let new_results = (prim_call "append" [(get (frame) ((String "results"))); (List [value])]) in let fenv = (get (frame) ((String "env"))) in (if sx_truthy ((Bool (List.exists (fun c -> sx_truthy ((empty_p (c)))) (sx_to_list remaining)))) then (make_cek_value (new_results) (fenv) (rest_k)) else (let heads = (List (List.map (fun c -> (first (c))) (sx_to_list remaining))) in let tails = (List (List.map (fun c -> (rest (c))) (sx_to_list remaining))) in (continue_with_call (f) (heads) (fenv) ((List [])) ((kont_push ((make_multi_map_frame (f) (tails) (new_results) (fenv))) (rest_k))))))) else (if sx_truthy ((prim_call "=" [_match_val; (String "callcc")])) then (let k = (make_callcc_continuation (rest_k)) in (continue_with_call (value) ((List [k])) ((get (frame) ((String "env")))) ((List [k])) (rest_k))) else (if sx_truthy ((prim_call "=" [_match_val; (String "vm-resume")])) then (let resume_fn = (get (frame) ((String "f"))) in (let result' = (sx_apply resume_fn (List [value])) in (if sx_truthy ((let _and = (dict_p (result')) in if not (sx_truthy _and) then _and else (get (result') ((String "__vm_suspended"))))) then (make_cek_suspended ((get (result') ((String "request")))) ((get (frame) ((String "env")))) ((kont_push ((make_vm_resume_frame ((get (result') ((String "resume")))) ((get (frame) ((String "env")))))) (rest_k)))) else (make_cek_value (result') ((get (frame) ((String "env")))) (rest_k))))) else (if sx_truthy ((prim_call "=" [_match_val; (String "perform")])) then (make_cek_suspended (value) ((get (frame) ((String "env")))) (rest_k)) else (if sx_truthy ((prim_call "=" [_match_val; (String "import")])) then (let import_set = (get (frame) ((String "args"))) in let remaining_sets = (get (frame) ((String "remaining"))) in let fenv = (get (frame) ((String "env"))) in (let () = ignore ((bind_import_set (import_set) (fenv))) in (if sx_truthy ((empty_p (remaining_sets))) then (make_cek_value (Nil) (fenv) (rest_k)) else (step_sf_import (remaining_sets) (fenv) (rest_k))))) else (if sx_truthy ((prim_call "=" [_match_val; (String "parameterize")])) then (let remaining = (get (frame) ((String "remaining"))) in let current_param = (get (frame) ((String "f"))) in let results = (get (frame) ((String "results"))) in let body = (get (frame) ((String "body"))) in let fenv = (get (frame) ((String "env"))) in (if sx_truthy ((is_nil (current_param))) then (let param_obj = value in let val_expr = (nth ((first (remaining))) ((Number 1.0))) in (make_cek_state (val_expr) (fenv) ((kont_push ((make_parameterize_frame (remaining) (param_obj) (results) (body) (fenv))) (rest_k))))) else (let converted_val = value in let new_results = (prim_call "append" [results; (List [(List [(parameter_uid (current_param)); converted_val])])]) in let rest_bindings = (rest (remaining)) in (if sx_truthy ((empty_p (rest_bindings))) then (let body_expr = (if sx_truthy ((prim_call "=" [(len (body)); (Number 1.0)])) then (first (body)) else (cons ((Symbol "begin")) (body))) in let provide_kont = (kont_push_provides (new_results) (fenv) (rest_k)) in (make_cek_state (body_expr) (fenv) (provide_kont))) else (make_cek_state ((first ((first (rest_bindings))))) (fenv) ((kont_push ((make_parameterize_frame (rest_bindings) (Nil) (new_results) (body) (fenv))) (rest_k)))))))) else (let () = ignore ((_last_error_kont_ref := rest_k; Nil)) in (raise (Eval_error (value_to_str (String (sx_str [(String "Unknown frame type: "); ft]))))))))))))))))))))))))))))))))))))))))))))))))))))
+  (let value = (cek_value (state)) in let env = (cek_env (state)) in let kont = (cek_kont (state)) in (if sx_truthy ((kont_empty_p (kont))) then state else (let frame = (kont_top (kont)) in let rest_k = (kont_pop (kont)) in let ft = (frame_type (frame)) in (let _match_val = ft in (if sx_truthy ((prim_call "=" [_match_val; (String "if")])) then (if sx_truthy ((let _and = value in if not (sx_truthy _and) then _and else (Bool (not (sx_truthy ((is_nil (value)))))))) then (make_cek_state ((get (frame) ((String "then")))) ((get (frame) ((String "env")))) (rest_k)) else (if sx_truthy ((is_nil ((get (frame) ((String "else")))))) then (make_cek_value (Nil) (env) (rest_k)) else (make_cek_state ((get (frame) ((String "else")))) ((get (frame) ((String "env")))) (rest_k)))) else (if sx_truthy ((prim_call "=" [_match_val; (String "when")])) then (if sx_truthy ((let _and = value in if not (sx_truthy _and) then _and else (Bool (not (sx_truthy ((is_nil (value)))))))) then (let body = (get (frame) ((String "body"))) in let fenv = (get (frame) ((String "env"))) in (if sx_truthy ((empty_p (body))) then (make_cek_value (Nil) (fenv) (rest_k)) else (if sx_truthy ((prim_call "=" [(len (body)); (Number 1.0)])) then (make_cek_state ((first (body))) (fenv) (rest_k)) else (make_cek_state ((first (body))) (fenv) ((kont_push ((make_begin_frame ((rest (body))) (fenv))) (rest_k))))))) else (make_cek_value (Nil) (env) (rest_k))) else (if sx_truthy ((prim_call "=" [_match_val; (String "begin")])) then (let remaining = (get (frame) ((String "remaining"))) in let fenv = (get (frame) ((String "env"))) in (if sx_truthy ((empty_p (remaining))) then (make_cek_value (value) (fenv) (rest_k)) else (if sx_truthy ((prim_call "=" [(len (remaining)); (Number 1.0)])) then (make_cek_state ((first (remaining))) (fenv) (rest_k)) else (make_cek_state ((first (remaining))) (fenv) ((kont_push ((make_begin_frame ((rest (remaining))) (fenv))) (rest_k))))))) else (if sx_truthy ((prim_call "=" [_match_val; (String "let")])) then (let name = (get (frame) ((String "name"))) in let remaining = (get (frame) ((String "remaining"))) in let body = (get (frame) ((String "body"))) in let local = (get (frame) ((String "env"))) in (let () = ignore ((env_bind local (sx_to_string name) value)) in (if sx_truthy ((empty_p (remaining))) then (step_sf_begin (body) (local) (rest_k)) else (let next_binding = (first (remaining)) in let vname = (if sx_truthy ((prim_call "=" [(type_of ((first (next_binding)))); (String "symbol")])) then (symbol_name ((first (next_binding)))) else (first (next_binding))) in (make_cek_state ((nth (next_binding) ((Number 1.0)))) (local) ((kont_push ((make_let_frame (vname) ((rest (remaining))) (body) (local))) (rest_k)))))))) else (if sx_truthy ((prim_call "=" [_match_val; (String "define")])) then (let name = (get (frame) ((String "name"))) in let fenv = (get (frame) ((String "env"))) in let has_effects = (get (frame) ((String "has-effects"))) in let effect_list = (get (frame) ((String "effect-list"))) in (let () = ignore ((if sx_truthy ((let _and = (is_lambda (value)) in if not (sx_truthy _and) then _and else (is_nil ((lambda_name (value)))))) then (set_lambda_name value (sx_to_string name)) else Nil)) in (let () = ignore ((env_bind fenv (sx_to_string name) value)) in (let () = ignore ((if sx_truthy (has_effects) then (let effect_names = (List (List.map (fun e -> (if sx_truthy ((prim_call "=" [(type_of (e)); (String "symbol")])) then (symbol_name (e)) else e)) (sx_to_list effect_list))) in let effect_anns = (if sx_truthy ((env_has (fenv) ((String "*effect-annotations*")))) then (env_get (fenv) ((String "*effect-annotations*"))) else (Dict (Hashtbl.create 0))) in (let () = ignore ((sx_dict_set_b effect_anns name effect_names)) in (env_bind fenv (sx_to_string (String "*effect-annotations*")) effect_anns))) else Nil)) in (make_cek_value (value) (fenv) (rest_k)))))) else (if sx_truthy ((prim_call "=" [_match_val; (String "define-foreign")])) then (let name = (get (frame) ((String "name"))) in let fenv = (get (frame) ((String "env"))) in (let () = ignore ((if sx_truthy ((let _and = (is_lambda (value)) in if not (sx_truthy _and) then _and else (is_nil ((lambda_name (value)))))) then (set_lambda_name value (sx_to_string name)) else Nil)) in (let () = ignore ((env_bind fenv (sx_to_string name) value)) in (make_cek_value (value) (fenv) (rest_k))))) else (if sx_truthy ((prim_call "=" [_match_val; (String "set")])) then (let name = (get (frame) ((String "name"))) in let fenv = (get (frame) ((String "env"))) in (let () = ignore ((env_set fenv (sx_to_string name) value)) in (make_cek_value (value) (env) (rest_k)))) else (if sx_truthy ((prim_call "=" [_match_val; (String "and")])) then (if sx_truthy ((Bool (not (sx_truthy (value))))) then (make_cek_value (value) (env) (rest_k)) else (let remaining = (get (frame) ((String "remaining"))) in (if sx_truthy ((empty_p (remaining))) then (make_cek_value (value) (env) (rest_k)) else (make_cek_state ((first (remaining))) ((get (frame) ((String "env")))) ((if sx_truthy ((prim_call "=" [(len (remaining)); (Number 1.0)])) then rest_k else (kont_push ((make_and_frame ((rest (remaining))) ((get (frame) ((String "env")))))) (rest_k)))))))) else (if sx_truthy ((prim_call "=" [_match_val; (String "or")])) then (if sx_truthy (value) then (make_cek_value (value) (env) (rest_k)) else (let remaining = (get (frame) ((String "remaining"))) in (if sx_truthy ((empty_p (remaining))) then (make_cek_value ((Bool false)) (env) (rest_k)) else (make_cek_state ((first (remaining))) ((get (frame) ((String "env")))) ((if sx_truthy ((prim_call "=" [(len (remaining)); (Number 1.0)])) then rest_k else (kont_push ((make_or_frame ((rest (remaining))) ((get (frame) ((String "env")))))) (rest_k)))))))) else (if sx_truthy ((prim_call "=" [_match_val; (String "cond")])) then (let remaining = (get (frame) ((String "remaining"))) in let fenv = (get (frame) ((String "env"))) in let scheme_p = (get (frame) ((String "scheme"))) in (if sx_truthy (scheme_p) then (if sx_truthy (value) then (let clause = (first (remaining)) in (if sx_truthy ((let _and = (prim_call ">" [(len (clause)); (Number 2.0)]) in if not (sx_truthy _and) then _and else (let _and = (prim_call "=" [(type_of ((nth (clause) ((Number 1.0))))); (String "symbol")]) in if not (sx_truthy _and) then _and else (prim_call "=" [(symbol_name ((nth (clause) ((Number 1.0))))); (String "=>")])))) then (make_cek_state ((nth (clause) ((Number 2.0)))) (fenv) ((kont_push ((make_cond_arrow_frame (value) (fenv))) (rest_k)))) else (make_cek_state ((nth (clause) ((Number 1.0)))) (fenv) (rest_k)))) else (let next_clauses = (rest (remaining)) in (if sx_truthy ((empty_p (next_clauses))) then (make_cek_value (Nil) (fenv) (rest_k)) else (let next_clause = (first (next_clauses)) in let next_test = (first (next_clause)) in (if sx_truthy ((is_else_clause (next_test))) then (make_cek_state ((nth (next_clause) ((Number 1.0)))) (fenv) (rest_k)) else (make_cek_state (next_test) (fenv) ((kont_push ((make_cond_frame (next_clauses) (fenv) ((Bool true)))) (rest_k))))))))) else (if sx_truthy (value) then (make_cek_state ((nth (remaining) ((Number 1.0)))) (fenv) (rest_k)) else (let next = (prim_call "slice" [remaining; (Number 2.0); (len (remaining))]) in (if sx_truthy ((prim_call "<" [(len (next)); (Number 2.0)])) then (make_cek_value (Nil) (fenv) (rest_k)) else (let next_test = (first (next)) in (if sx_truthy ((is_else_clause (next_test))) then (make_cek_state ((nth (next) ((Number 1.0)))) (fenv) (rest_k)) else (make_cek_state (next_test) (fenv) ((kont_push ((make_cond_frame (next) (fenv) ((Bool false)))) (rest_k))))))))))) else (if sx_truthy ((prim_call "=" [_match_val; (String "case")])) then (let match_val = (get (frame) ((String "match-val"))) in let remaining = (get (frame) ((String "remaining"))) in let fenv = (get (frame) ((String "env"))) in (if sx_truthy ((is_nil (match_val))) then (sf_case_step_loop (value) (remaining) (fenv) (rest_k)) else (sf_case_step_loop (match_val) (remaining) (fenv) (rest_k)))) else (if sx_truthy ((prim_call "=" [_match_val; (String "thread")])) then (let remaining = (get (frame) ((String "remaining"))) in let fenv = (get (frame) ((String "env"))) in let mode = (get (frame) ((String "extra"))) in let bind_name = (get (frame) ((String "name"))) in (if sx_truthy ((empty_p (remaining))) then (make_cek_value (value) (fenv) (rest_k)) else (let form = (first (remaining)) in let rest_forms = (rest (remaining)) in let new_kont = (if sx_truthy ((empty_p ((rest (remaining))))) then rest_k else (kont_push ((make_thread_frame ((rest (remaining))) (fenv) (mode) (bind_name))) (rest_k))) in (if sx_truthy ((prim_call "=" [mode; (String "as")])) then (let new_env = (env_extend (fenv)) in (let () = ignore ((env_bind new_env (sx_to_string (symbol_name (bind_name))) value)) in (make_cek_state (form) (new_env) (new_kont)))) else (if sx_truthy ((let _and = (prim_call "=" [(type_of (form)); (String "list")]) in if not (sx_truthy _and) then _and else (let _and = (Bool (not (sx_truthy ((empty_p (form)))))) in if not (sx_truthy _and) then _and else (let _and = (prim_call "=" [(type_of ((first (form)))); (String "symbol")]) in if not (sx_truthy _and) then _and else (ho_form_name_p ((symbol_name ((first (form)))))))))) then (make_cek_state ((cons ((first (form))) ((cons ((List [(Symbol "quote"); value])) ((rest (form))))))) (fenv) (new_kont)) else (if sx_truthy ((prim_call "=" [mode; (String "last")])) then (let result' = (thread_insert_arg_last (form) (value) (fenv)) in (if sx_truthy ((empty_p (rest_forms))) then (make_cek_value (result') (fenv) (rest_k)) else (make_cek_value (result') (fenv) ((kont_push ((make_thread_frame (rest_forms) (fenv) (mode) (bind_name))) (rest_k)))))) else (let result' = (thread_insert_arg (form) (value) (fenv)) in (if sx_truthy ((empty_p (rest_forms))) then (make_cek_value (result') (fenv) (rest_k)) else (make_cek_value (result') (fenv) ((kont_push ((make_thread_frame (rest_forms) (fenv) (mode) (bind_name))) (rest_k)))))))))))) else (if sx_truthy ((prim_call "=" [_match_val; (String "arg")])) then (let f = (get (frame) ((String "f"))) in let evaled = (get (frame) ((String "evaled"))) in let remaining = (get (frame) ((String "remaining"))) in let fenv = (get (frame) ((String "env"))) in let raw_args = (get (frame) ((String "raw-args"))) in let hname = (get (frame) ((String "head-name"))) in (if sx_truthy ((is_nil (f))) then (let () = ignore ((if sx_truthy ((let _and = !_strict_ref in if not (sx_truthy _and) then _and else hname)) then (strict_check_args (hname) ((List []))) else Nil)) in (if sx_truthy ((empty_p (remaining))) then (continue_with_call (value) ((List [])) (fenv) (raw_args) (rest_k)) else (make_cek_state ((first (remaining))) (fenv) ((kont_push ((make_arg_frame (value) ((List [])) ((rest (remaining))) (fenv) (raw_args) (hname))) (rest_k)))))) else (let new_evaled = (prim_call "append" [evaled; (List [value])]) in (if sx_truthy ((empty_p (remaining))) then (let () = ignore ((if sx_truthy ((let _and = !_strict_ref in if not (sx_truthy _and) then _and else hname)) then (strict_check_args (hname) (new_evaled)) else Nil)) in (continue_with_call (f) (new_evaled) (fenv) (raw_args) (rest_k))) else (make_cek_state ((first (remaining))) (fenv) ((kont_push ((make_arg_frame (f) (new_evaled) ((rest (remaining))) (fenv) (raw_args) (hname))) (rest_k)))))))) else (if sx_truthy ((prim_call "=" [_match_val; (String "dict")])) then (let remaining = (get (frame) ((String "remaining"))) in let results = (get (frame) ((String "results"))) in let fenv = (get (frame) ((String "env"))) in (let last_result = (last (results)) in let completed = (prim_call "append" [(prim_call "slice" [results; (Number 0.0); (prim_call "dec" [(len (results))])]); (List [(List [(first (last_result)); value])])]) in (if sx_truthy ((empty_p (remaining))) then (let d = (Dict (Hashtbl.create 0)) in (let () = ignore ((List.iter (fun pair -> ignore ((sx_dict_set_b d (first (pair)) (nth (pair) ((Number 1.0)))))) (sx_to_list completed); Nil)) in (make_cek_value (d) (fenv) (rest_k)))) else (let next_entry = (first (remaining)) in (make_cek_state ((nth (next_entry) ((Number 1.0)))) (fenv) ((kont_push ((make_dict_frame ((rest (remaining))) ((prim_call "append" [completed; (List [(List [(first (next_entry))])])])) (fenv))) (rest_k)))))))) else (if sx_truthy ((prim_call "=" [_match_val; (String "ho-setup")])) then (let ho_type = (get (frame) ((String "ho-type"))) in let remaining = (get (frame) ((String "remaining"))) in let evaled = (prim_call "append" [(get (frame) ((String "evaled"))); (List [value])]) in let fenv = (get (frame) ((String "env"))) in (if sx_truthy ((empty_p (remaining))) then (ho_setup_dispatch (ho_type) (evaled) (fenv) (rest_k)) else (make_cek_state ((first (remaining))) (fenv) ((kont_push ((make_ho_setup_frame (ho_type) ((rest (remaining))) (evaled) (fenv))) (rest_k)))))) else (if sx_truthy ((prim_call "=" [_match_val; (String "reset")])) then (make_cek_value (value) (env) (rest_k)) else (if sx_truthy ((prim_call "=" [_match_val; (String "deref")])) then (let val' = value in let fenv = (get (frame) ((String "env"))) in (if sx_truthy ((Bool (not (sx_truthy ((is_signal (val'))))))) then (make_cek_value (val') (fenv) (rest_k)) else (if sx_truthy ((has_reactive_reset_frame_p (rest_k))) then (reactive_shift_deref (val') (fenv) (rest_k)) else (let () = ignore ((let ctx = (sx_context ((String "sx-reactive")) (Nil)) in (if sx_truthy (ctx) then (let dep_list = ref ((get (ctx) ((String "deps")))) in let notify_fn = (get (ctx) ((String "notify"))) in (if sx_truthy ((Bool (not (sx_truthy ((prim_call "contains?" [!dep_list; val'])))))) then (let () = ignore ((dep_list := sx_append_b !dep_list val'; Nil)) in (signal_add_sub_b (val') (notify_fn))) else Nil)) else Nil))) in (make_cek_value ((signal_value (val'))) (fenv) (rest_k)))))) else (if sx_truthy ((prim_call "=" [_match_val; (String "reactive-reset")])) then (let update_fn = (get (frame) ((String "update-fn"))) in let first_p = (get (frame) ((String "first-render"))) in (let () = ignore ((if sx_truthy ((let _and = update_fn in if not (sx_truthy _and) then _and else (Bool (not (sx_truthy (first_p)))))) then (cek_call (update_fn) ((List [value]))) else Nil)) in (make_cek_value (value) (env) (rest_k)))) else (if sx_truthy ((prim_call "=" [_match_val; (String "scope")])) then (let name = (get (frame) ((String "name"))) in let remaining = (get (frame) ((String "remaining"))) in let fenv = (get (frame) ((String "env"))) in (if sx_truthy ((empty_p (remaining))) then (let () = ignore ((scope_pop (name))) in (make_cek_value (value) (fenv) (rest_k))) else (make_cek_state ((first (remaining))) (fenv) ((kont_push ((make_scope_frame (name) ((rest (remaining))) (fenv))) (rest_k)))))) else (if sx_truthy ((prim_call "=" [_match_val; (String "provide")])) then (let remaining = (get (frame) ((String "remaining"))) in let fenv = (get (frame) ((String "env"))) in (if sx_truthy ((empty_p (remaining))) then (let () = ignore ((scope_pop ((get (frame) ((String "name")))))) in (make_cek_value (value) (fenv) (rest_k))) else (let new_frame = (make_provide_frame ((get (frame) ((String "name")))) ((get (frame) ((String "value")))) ((rest (remaining))) (fenv)) in (let () = ignore ((sx_dict_set_b new_frame (String "subscribers") (get (frame) ((String "subscribers"))))) in (make_cek_state ((first (remaining))) (fenv) ((kont_push (new_frame) (rest_k)))))))) else (if sx_truthy ((prim_call "=" [_match_val; (String "bind")])) then (let tracked = !_bind_tracking_ref in let body = (get (frame) ((String "body"))) in let fenv = (get (frame) ((String "env"))) in let prev = (get (frame) ((String "prev-tracking"))) in (let () = ignore ((_bind_tracking_ref := prev; Nil)) in (let () = ignore ((let subscriber = (NativeFn ("\206\187", fun _args -> match _args with [fire_kont] -> (fun fire_kont -> (cek_run ((make_cek_state (body) (fenv) ((List [])))))) fire_kont | _ -> Nil)) in (List.iter (fun name -> ignore ((let existing = (get (!_provide_subscribers_ref) (name)) in (sx_dict_set_b !_provide_subscribers_ref name (prim_call "append" [(if sx_truthy (existing) then existing else (List [])); (List [subscriber])]))))) (sx_to_list tracked); Nil))) in (make_cek_value (value) (fenv) (rest_k))))) else (if sx_truthy ((prim_call "=" [_match_val; (String "provide-set")])) then (let name = (get (frame) ((String "name"))) in let fenv = (get (frame) ((String "env"))) in let target = (kont_find_provide (rest_k) (name)) in (let old_val = (if sx_truthy (target) then (get (target) ((String "value"))) else (scope_peek (name))) in (let () = ignore ((if sx_truthy (target) then (sx_dict_set_b target (String "value") value) else Nil)) in (let () = ignore ((scope_pop (name))) in (let () = ignore ((scope_push (name) (value))) in (let () = ignore ((if sx_truthy ((Bool (not (sx_truthy ((prim_call "=" [old_val; value])))))) then (fire_provide_subscribers (name)) else Nil)) in (make_cek_value (value) (fenv) (rest_k)))))))) else (if sx_truthy ((prim_call "=" [_match_val; (String "scope-acc")])) then (let remaining = (get (frame) ((String "remaining"))) in let fenv = (get (frame) ((String "env"))) in (if sx_truthy ((empty_p (remaining))) then (make_cek_value (value) (fenv) (rest_k)) else (make_cek_state ((first (remaining))) (fenv) ((kont_push ((let new_frame = (make_scope_acc_frame ((get (frame) ((String "name")))) ((get (frame) ((String "value")))) ((rest (remaining))) (fenv)) in (let () = ignore ((sx_dict_set_b new_frame (String "emitted") (get (frame) ((String "emitted"))))) in new_frame))) (rest_k)))))) else (if sx_truthy ((prim_call "=" [_match_val; (String "map")])) then (let f = (get (frame) ((String "f"))) in let remaining = (get (frame) ((String "remaining"))) in let results = (get (frame) ((String "results"))) in let indexed = (get (frame) ((String "indexed"))) in let fenv = (get (frame) ((String "env"))) in (let new_results = (prim_call "append" [results; (List [value])]) in (if sx_truthy ((empty_p (remaining))) then (make_cek_value (new_results) (fenv) (rest_k)) else (let call_args = (if sx_truthy (indexed) then (List [(len (new_results)); (first (remaining))]) else (List [(first (remaining))])) in let next_frame = (if sx_truthy (indexed) then (make_map_indexed_frame (f) ((rest (remaining))) (new_results) (fenv)) else (make_map_frame (f) ((rest (remaining))) (new_results) (fenv))) in (continue_with_call (f) (call_args) (fenv) ((List [])) ((kont_push (next_frame) (rest_k)))))))) else (if sx_truthy ((prim_call "=" [_match_val; (String "filter")])) then (let f = (get (frame) ((String "f"))) in let remaining = (get (frame) ((String "remaining"))) in let results = (get (frame) ((String "results"))) in let current_item = (get (frame) ((String "current-item"))) in let fenv = (get (frame) ((String "env"))) in (let new_results = (if sx_truthy (value) then (prim_call "append" [results; (List [current_item])]) else results) in (if sx_truthy ((empty_p (remaining))) then (make_cek_value (new_results) (fenv) (rest_k)) else (continue_with_call (f) ((List [(first (remaining))])) (fenv) ((List [])) ((kont_push ((make_filter_frame (f) ((rest (remaining))) (new_results) ((first (remaining))) (fenv))) (rest_k))))))) else (if sx_truthy ((prim_call "=" [_match_val; (String "reduce")])) then (let f = (get (frame) ((String "f"))) in let remaining = (get (frame) ((String "remaining"))) in let fenv = (get (frame) ((String "env"))) in (if sx_truthy ((empty_p (remaining))) then (make_cek_value (value) (fenv) (rest_k)) else (continue_with_call (f) ((List [value; (first (remaining))])) (fenv) ((List [])) ((kont_push ((make_reduce_frame (f) ((rest (remaining))) (fenv))) (rest_k)))))) else (if sx_truthy ((prim_call "=" [_match_val; (String "for-each")])) then (let f = (get (frame) ((String "f"))) in let remaining = (get (frame) ((String "remaining"))) in let fenv = (get (frame) ((String "env"))) in (if sx_truthy ((empty_p (remaining))) then (make_cek_value (Nil) (fenv) (rest_k)) else (continue_with_call (f) ((List [(first (remaining))])) (fenv) ((List [])) ((kont_push ((make_for_each_frame (f) ((rest (remaining))) (fenv))) (rest_k)))))) else (if sx_truthy ((prim_call "=" [_match_val; (String "some")])) then (let f = (get (frame) ((String "f"))) in let remaining = (get (frame) ((String "remaining"))) in let fenv = (get (frame) ((String "env"))) in (if sx_truthy (value) then (make_cek_value (value) (fenv) (rest_k)) else (if sx_truthy ((empty_p (remaining))) then (make_cek_value ((Bool false)) (fenv) (rest_k)) else (continue_with_call (f) ((List [(first (remaining))])) (fenv) ((List [])) ((kont_push ((make_some_frame (f) ((rest (remaining))) (fenv))) (rest_k))))))) else (if sx_truthy ((prim_call "=" [_match_val; (String "every")])) then (let f = (get (frame) ((String "f"))) in let remaining = (get (frame) ((String "remaining"))) in let fenv = (get (frame) ((String "env"))) in (if sx_truthy ((Bool (not (sx_truthy (value))))) then (make_cek_value ((Bool false)) (fenv) (rest_k)) else (if sx_truthy ((empty_p (remaining))) then (make_cek_value ((Bool true)) (fenv) (rest_k)) else (continue_with_call (f) ((List [(first (remaining))])) (fenv) ((List [])) ((kont_push ((make_every_frame (f) ((rest (remaining))) (fenv))) (rest_k))))))) else (if sx_truthy ((prim_call "=" [_match_val; (String "handler")])) then (let remaining = (get (frame) ((String "remaining"))) in let fenv = (get (frame) ((String "env"))) in (if sx_truthy ((empty_p (remaining))) then (make_cek_value (value) (fenv) (rest_k)) else (make_cek_state ((first (remaining))) (fenv) ((kont_push ((make_handler_frame ((get (frame) ((String "f")))) ((rest (remaining))) (fenv))) (rest_k)))))) else (if sx_truthy ((prim_call "=" [_match_val; (String "restart")])) then (make_cek_value (value) (env) (rest_k)) else (if sx_truthy ((prim_call "=" [_match_val; (String "signal-return")])) then (let saved_kont = (get (frame) ((String "saved-kont"))) in (make_cek_value (value) ((get (frame) ((String "env")))) (saved_kont))) else (if sx_truthy ((prim_call "=" [_match_val; (String "comp-trace")])) then (make_cek_value (value) (env) (rest_k)) else (if sx_truthy ((prim_call "=" [_match_val; (String "cond-arrow")])) then (let test_value = (get (frame) ((String "match-val"))) in let fenv = (get (frame) ((String "env"))) in (continue_with_call (value) ((List [test_value])) (fenv) ((List [test_value])) (rest_k))) else (if sx_truthy ((prim_call "=" [_match_val; (String "wind-after")])) then (let after_thunk = (get (frame) ((String "after-thunk"))) in let winders_len = (get (frame) ((String "winders-len"))) in let body_result = value in let fenv = (get (frame) ((String "env"))) in (let () = ignore ((if sx_truthy ((prim_call ">" [(len (!_winders_ref)); winders_len])) then (_winders_ref := (rest (!_winders_ref)); Nil) else Nil)) in (continue_with_call (after_thunk) ((List [])) (fenv) ((List [])) ((kont_push ((make_wind_return_frame (body_result) (fenv))) (rest_k)))))) else (if sx_truthy ((prim_call "=" [_match_val; (String "wind-return")])) then (make_cek_value ((get (frame) ((String "body-result")))) ((get (frame) ((String "env")))) (rest_k)) else (if sx_truthy ((prim_call "=" [_match_val; (String "raise-eval")])) then (let condition = value in let fenv = (get (frame) ((String "env"))) in let continuable_p = (get (frame) ((String "scheme"))) in let unwind_result = (kont_unwind_to_handler (rest_k) (condition)) in let handler_fn = (get (unwind_result) ((String "handler"))) in let unwound_k = (get (unwind_result) ((String "kont"))) in (if sx_truthy ((is_nil (handler_fn))) then (let () = ignore ((_last_error_kont_ref := unwound_k; Nil)) in (host_error ((String (sx_str [(String "Unhandled exception: "); (inspect (condition))]))))) else (continue_with_call (handler_fn) ((List [condition])) (fenv) ((List [condition])) ((if sx_truthy (continuable_p) then (kont_push ((make_signal_return_frame (fenv) (unwound_k))) (unwound_k)) else (kont_push ((make_raise_guard_frame (fenv) (unwound_k))) (unwound_k))))))) else (if sx_truthy ((prim_call "=" [_match_val; (String "raise-guard")])) then (let () = ignore ((_last_error_kont_ref := rest_k; Nil)) in (host_error ((String "exception handler returned from non-continuable raise")))) else (if sx_truthy ((prim_call "=" [_match_val; (String "multi-map")])) then (let f = (get (frame) ((String "f"))) in let remaining = (get (frame) ((String "remaining"))) in let new_results = (prim_call "append" [(get (frame) ((String "results"))); (List [value])]) in let fenv = (get (frame) ((String "env"))) in (if sx_truthy ((Bool (List.exists (fun c -> sx_truthy ((empty_p (c)))) (sx_to_list remaining)))) then (make_cek_value (new_results) (fenv) (rest_k)) else (let heads = (List (List.map (fun c -> (first (c))) (sx_to_list remaining))) in let tails = (List (List.map (fun c -> (rest (c))) (sx_to_list remaining))) in (continue_with_call (f) (heads) (fenv) ((List [])) ((kont_push ((make_multi_map_frame (f) (tails) (new_results) (fenv))) (rest_k))))))) else (if sx_truthy ((prim_call "=" [_match_val; (String "callcc")])) then (let k = (make_callcc_continuation (rest_k) ((len (!_winders_ref)))) in (continue_with_call (value) ((List [k])) ((get (frame) ((String "env")))) ((List [k])) (rest_k))) else (if sx_truthy ((prim_call "=" [_match_val; (String "vm-resume")])) then (let resume_fn = (get (frame) ((String "f"))) in (let result' = (sx_apply resume_fn (List [value])) in (if sx_truthy ((let _and = (dict_p (result')) in if not (sx_truthy _and) then _and else (get (result') ((String "__vm_suspended"))))) then (make_cek_suspended ((get (result') ((String "request")))) ((get (frame) ((String "env")))) ((kont_push ((make_vm_resume_frame ((get (result') ((String "resume")))) ((get (frame) ((String "env")))))) (rest_k)))) else (make_cek_value (result') ((get (frame) ((String "env")))) (rest_k))))) else (if sx_truthy ((prim_call "=" [_match_val; (String "perform")])) then (make_cek_suspended (value) ((get (frame) ((String "env")))) (rest_k)) else (if sx_truthy ((prim_call "=" [_match_val; (String "import")])) then (let import_set = (get (frame) ((String "args"))) in let remaining_sets = (get (frame) ((String "remaining"))) in let fenv = (get (frame) ((String "env"))) in (let () = ignore ((bind_import_set (import_set) (fenv))) in (if sx_truthy ((empty_p (remaining_sets))) then (make_cek_value (Nil) (fenv) (rest_k)) else (step_sf_import (remaining_sets) (fenv) (rest_k))))) else (if sx_truthy ((prim_call "=" [_match_val; (String "parameterize")])) then (let remaining = (get (frame) ((String "remaining"))) in let current_param = (get (frame) ((String "f"))) in let results = (get (frame) ((String "results"))) in let body = (get (frame) ((String "body"))) in let fenv = (get (frame) ((String "env"))) in (if sx_truthy ((is_nil (current_param))) then (let param_obj = value in let val_expr = (nth ((first (remaining))) ((Number 1.0))) in (make_cek_state (val_expr) (fenv) ((kont_push ((make_parameterize_frame (remaining) (param_obj) (results) (body) (fenv))) (rest_k))))) else (let converted_val = value in let new_results = (prim_call "append" [results; (List [(List [(parameter_uid (current_param)); converted_val])])]) in let rest_bindings = (rest (remaining)) in (if sx_truthy ((empty_p (rest_bindings))) then (let body_expr = (if sx_truthy ((prim_call "=" [(len (body)); (Number 1.0)])) then (first (body)) else (cons ((Symbol "begin")) (body))) in let provide_kont = (kont_push_provides (new_results) (fenv) (rest_k)) in (make_cek_state (body_expr) (fenv) (provide_kont))) else (make_cek_state ((first ((first (rest_bindings))))) (fenv) ((kont_push ((make_parameterize_frame (rest_bindings) (Nil) (new_results) (body) (fenv))) (rest_k)))))))) else (let () = ignore ((_last_error_kont_ref := rest_k; Nil)) in (raise (Eval_error (value_to_str (String (sx_str [(String "Unknown frame type: "); ft]))))))))))))))))))))))))))))))))))))))))))))))))))))))
 
 (* continue-with-call *)
 and continue_with_call f args env raw_args kont =
-  (if sx_truthy ((parameter_p (f))) then (let uid = (parameter_uid (f)) in let frame = (kont_find_provide (kont) (uid)) in (make_cek_value ((if sx_truthy (frame) then (get (frame) ((String "value"))) else (parameter_default (f)))) (env) (kont))) else (if sx_truthy ((callcc_continuation_p (f))) then (let arg = (if sx_truthy ((empty_p (args))) then Nil else (first (args))) in let captured = (callcc_continuation_data (f)) in (make_cek_value (arg) (env) (captured))) else (if sx_truthy ((continuation_p (f))) then (let arg = (if sx_truthy ((empty_p (args))) then Nil else (first (args))) in let cont_data = (continuation_data (f)) in (let captured = (get (cont_data) ((String "captured"))) in (let result' = (cek_run ((make_cek_value (arg) (env) (captured)))) in (make_cek_value (result') (env) (kont))))) else (if sx_truthy ((let _and = (is_callable (f)) in if not (sx_truthy _and) then _and else (let _and = (Bool (not (sx_truthy ((is_lambda (f)))))) in if not (sx_truthy _and) then _and else (let _and = (Bool (not (sx_truthy ((is_component (f)))))) in if not (sx_truthy _and) then _and else (Bool (not (sx_truthy ((is_island (f)))))))))) then (let result' = (sx_apply_cek (f) (args)) in (if sx_truthy ((Bool (is_eval_error result'))) then (make_cek_value ((get (result') ((String "message")))) (env) ((kont_push ((make_raise_eval_frame (env) ((Bool false)))) (kont)))) else (if sx_truthy ((let _and = (dict_p (result')) in if not (sx_truthy _and) then _and else (get (result') ((String "__vm_suspended"))))) then (make_cek_suspended ((get (result') ((String "request")))) (env) ((kont_push ((make_vm_resume_frame ((get (result') ((String "resume")))) (env))) (kont)))) else (make_cek_value (result') (env) (kont))))) else (if sx_truthy ((is_lambda (f))) then (let params = (lambda_params (f)) in let local = (env_merge ((lambda_closure (f))) (env)) in (let () = ignore ((if sx_truthy ((Bool (not (sx_truthy ((bind_lambda_params (params) (args) (local))))))) then (let () = ignore ((if sx_truthy ((prim_call ">" [(len (args)); (len (params))])) then (raise (Eval_error (value_to_str (String (sx_str [(let _or = (lambda_name (f)) in if sx_truthy _or then _or else (String "lambda")); (String " expects "); (len (params)); (String " args, got "); (len (args))]))))) else Nil)) in (let () = ignore ((List.iter (fun pair -> ignore ((env_bind local (sx_to_string (first (pair))) (nth (pair) ((Number 1.0)))))) (sx_to_list (prim_call "zip" [params; args])); Nil)) in (List.iter (fun p -> ignore ((env_bind local (sx_to_string p) Nil))) (sx_to_list (prim_call "slice" [params; (len (args))])); Nil))) else Nil)) in (let jit_result = (jit_try_call (f) (args)) in (if sx_truthy ((jit_skip_p (jit_result))) then (make_cek_state ((lambda_body (f))) (local) (kont)) else (if sx_truthy ((let _and = (dict_p (jit_result)) in if not (sx_truthy _and) then _and else (get (jit_result) ((String "__vm_suspended"))))) then (make_cek_suspended ((get (jit_result) ((String "request")))) (env) ((kont_push ((make_vm_resume_frame ((get (jit_result) ((String "resume")))) (env))) (kont)))) else (make_cek_value (jit_result) (local) (kont))))))) else (if sx_truthy ((let _or = (is_component (f)) in if sx_truthy _or then _or else (is_island (f)))) then (let parsed = (parse_keyword_args (raw_args) (env)) in let kwargs = (first (parsed)) in let children = (nth (parsed) ((Number 1.0))) in let local = (env_merge ((component_closure (f))) (env)) in (let () = ignore ((List.iter (fun p -> ignore ((env_bind local (sx_to_string p) (let _or = (dict_get (kwargs) (p)) in if sx_truthy _or then _or else Nil)))) (sx_to_list (component_params (f))); Nil)) in (let () = ignore ((if sx_truthy ((component_has_children (f))) then (env_bind local (sx_to_string (String "children")) children) else Nil)) in (make_cek_state ((component_body (f))) (local) ((kont_push ((make_comp_trace_frame ((component_name (f))) ((component_file (f))))) (kont))))))) else (let kont_info = (match kont with List frames | ListRef { contents = frames } -> Printf.sprintf " (kont=%d frames)" (List.length frames) | _ -> "") in raise (Eval_error (value_to_str (String (sx_str [(String "Not callable: "); (inspect (f)); (String kont_info)])))))))))))
+  (if sx_truthy ((parameter_p (f))) then (let uid = (parameter_uid (f)) in let frame = (kont_find_provide (kont) (uid)) in (make_cek_value ((if sx_truthy (frame) then (get (frame) ((String "value"))) else (parameter_default (f)))) (env) (kont))) else (if sx_truthy ((callcc_continuation_p (f))) then (let arg = (if sx_truthy ((empty_p (args))) then Nil else (first (args))) in let captured = (callcc_continuation_data (f)) in let w_len = (callcc_continuation_winders_len (f)) in (let () = ignore ((wind_escape_to (w_len))) in (make_cek_value (arg) (env) (captured)))) else (if sx_truthy ((continuation_p (f))) then (let arg = (if sx_truthy ((empty_p (args))) then Nil else (first (args))) in let cont_data = (continuation_data (f)) in (let captured = (get (cont_data) ((String "captured"))) in (let result' = (cek_run ((make_cek_value (arg) (env) (captured)))) in (make_cek_value (result') (env) (kont))))) else (if sx_truthy ((let _and = (is_callable (f)) in if not (sx_truthy _and) then _and else (let _and = (Bool (not (sx_truthy ((is_lambda (f)))))) in if not (sx_truthy _and) then _and else (let _and = (Bool (not (sx_truthy ((is_component (f)))))) in if not (sx_truthy _and) then _and else (Bool (not (sx_truthy ((is_island (f)))))))))) then (let result' = (sx_apply_cek (f) (args)) in (if sx_truthy ((Bool (is_eval_error result'))) then (make_cek_value ((get (result') ((String "message")))) (env) ((kont_push ((make_raise_eval_frame (env) ((Bool false)))) (kont)))) else (if sx_truthy ((let _and = (dict_p (result')) in if not (sx_truthy _and) then _and else (get (result') ((String "__vm_suspended"))))) then (make_cek_suspended ((get (result') ((String "request")))) (env) ((kont_push ((make_vm_resume_frame ((get (result') ((String "resume")))) (env))) (kont)))) else (make_cek_value (result') (env) (kont))))) else (if sx_truthy ((is_lambda (f))) then (let params = (lambda_params (f)) in let local = (env_merge ((lambda_closure (f))) (env)) in (let () = ignore ((if sx_truthy ((Bool (not (sx_truthy ((bind_lambda_params (params) (args) (local))))))) then (let () = ignore ((if sx_truthy ((prim_call ">" [(len (args)); (len (params))])) then (raise (Eval_error (value_to_str (String (sx_str [(let _or = (lambda_name (f)) in if sx_truthy _or then _or else (String "lambda")); (String " expects "); (len (params)); (String " args, got "); (len (args))]))))) else Nil)) in (let () = ignore ((List.iter (fun pair -> ignore ((env_bind local (sx_to_string (first (pair))) (nth (pair) ((Number 1.0)))))) (sx_to_list (prim_call "zip" [params; args])); Nil)) in (List.iter (fun p -> ignore ((env_bind local (sx_to_string p) Nil))) (sx_to_list (prim_call "slice" [params; (len (args))])); Nil))) else Nil)) in (let jit_result = (jit_try_call (f) (args)) in (if sx_truthy ((jit_skip_p (jit_result))) then (make_cek_state ((lambda_body (f))) (local) (kont)) else (if sx_truthy ((let _and = (dict_p (jit_result)) in if not (sx_truthy _and) then _and else (get (jit_result) ((String "__vm_suspended"))))) then (make_cek_suspended ((get (jit_result) ((String "request")))) (env) ((kont_push ((make_vm_resume_frame ((get (jit_result) ((String "resume")))) (env))) (kont)))) else (make_cek_value (jit_result) (local) (kont))))))) else (if sx_truthy ((let _or = (is_component (f)) in if sx_truthy _or then _or else (is_island (f)))) then (let parsed = (parse_keyword_args (raw_args) (env)) in let kwargs = (first (parsed)) in let children = (nth (parsed) ((Number 1.0))) in let local = (env_merge ((component_closure (f))) (env)) in (let () = ignore ((List.iter (fun p -> ignore ((env_bind local (sx_to_string p) (let _or = (dict_get (kwargs) (p)) in if sx_truthy _or then _or else Nil)))) (sx_to_list (component_params (f))); Nil)) in (let () = ignore ((if sx_truthy ((component_has_children (f))) then (env_bind local (sx_to_string (String "children")) children) else Nil)) in (make_cek_state ((component_body (f))) (local) ((kont_push ((make_comp_trace_frame ((component_name (f))) ((component_file (f))))) (kont))))))) else (raise (Eval_error (value_to_str (String (sx_str [(String "Not callable: "); (inspect (f))])))))))))))
 
 (* sf-case-step-loop *)
 and sf_case_step_loop match_val clauses env kont =
diff --git a/hosts/ocaml/lib/sx_runtime.ml b/hosts/ocaml/lib/sx_runtime.ml
index bb36af60..241eddcd 100644
--- a/hosts/ocaml/lib/sx_runtime.ml
+++ b/hosts/ocaml/lib/sx_runtime.ml
@@ -46,7 +46,7 @@ let sx_call f args =
     !Sx_types._cek_eval_lambda_ref f args
   | Continuation (k, _) ->
     k (match args with x :: _ -> x | [] -> Nil)
-  | CallccContinuation _ ->
+  | CallccContinuation (_, _) ->
     raise (Eval_error "callcc continuations must be invoked through the CEK machine")
   | _ ->
     let nargs = List.length args in
@@ -156,6 +156,9 @@ let get_val container key =
      | "extra" -> f.cf_extra | "extra2" -> f.cf_extra2
      | "subscribers" -> f.cf_results
      | "prev-tracking" -> f.cf_extra
+     | "after-thunk" -> f.cf_f        (* wind-after frame *)
+     | "winders-len" -> f.cf_extra    (* wind-after frame *)
+     | "body-result" -> f.cf_name     (* wind-return frame *)
      | _ -> Nil)
   | VmFrame f, String k ->
     (match k with
@@ -381,15 +384,20 @@ let continuation_data v = match v with
   | _ -> raise (Eval_error "not a continuation")
 
 (* Callcc (undelimited) continuation support *)
-let callcc_continuation_p v = match v with CallccContinuation _ -> Bool true | _ -> Bool false
+let callcc_continuation_p v = match v with CallccContinuation (_, _) -> Bool true | _ -> Bool false
 
-let make_callcc_continuation captured =
-  CallccContinuation (sx_to_list captured)
+let make_callcc_continuation captured winders_len =
+  let n = match winders_len with Number f -> int_of_float f | Integer n -> n | _ -> 0 in
+  CallccContinuation (sx_to_list captured, n)
 
 let callcc_continuation_data v = match v with
-  | CallccContinuation frames -> List frames
+  | CallccContinuation (frames, _) -> List frames
   | _ -> raise (Eval_error "not a callcc continuation")
 
+let callcc_continuation_winders_len v = match v with
+  | CallccContinuation (_, n) -> Number (float_of_int n)
+  | _ -> Number 0.0
+
 (* Dynamic wind — simplified for OCaml (no async) *)
 let host_error msg =
   raise (Eval_error (value_to_str msg))
diff --git a/hosts/ocaml/lib/sx_types.ml b/hosts/ocaml/lib/sx_types.ml
index 72271272..41e7dbf9 100644
--- a/hosts/ocaml/lib/sx_types.ml
+++ b/hosts/ocaml/lib/sx_types.ml
@@ -57,7 +57,7 @@ and value =
   | Macro  of macro
   | Thunk  of value * env
   | Continuation of (value -> value) * dict option
-  | CallccContinuation of value list  (** Undelimited continuation — captured kont frames *)
+  | CallccContinuation of value list * int  (** Undelimited continuation — captured kont frames + winders depth at capture *)
   | NativeFn of string * (value list -> value)
   | Signal of signal
   | RawHTML of string
@@ -476,7 +476,7 @@ let type_of = function
   | Macro _        -> "macro"
   | Thunk _        -> "thunk"
   | Continuation (_, _) -> "continuation"
-  | CallccContinuation _ -> "continuation"
+  | CallccContinuation (_, _) -> "continuation"
   | NativeFn _     -> "function"
   | Signal _       -> "signal"
   | RawHTML _      -> "raw-html"
@@ -506,7 +506,7 @@ let is_signal = function
 let is_record = function Record _ -> true | _ -> false
 
 let is_callable = function
-  | Lambda _ | NativeFn _ | Continuation (_, _) | CallccContinuation _ | VmClosure _ -> true
+  | Lambda _ | NativeFn _ | Continuation (_, _) | CallccContinuation (_, _) | VmClosure _ -> true
   | _ -> false
 
 
@@ -815,7 +815,7 @@ let rec inspect = function
     Printf.sprintf "<%s(%s)>" tag (String.concat ", " m.m_params)
   | Thunk _ -> "<thunk>"
   | Continuation (_, _) -> "<continuation>"
-  | CallccContinuation _ -> "<callcc-continuation>"
+  | CallccContinuation (_, _) -> "<callcc-continuation>"
   | NativeFn (name, _) -> Printf.sprintf "<native:%s>" name
   | Signal _ -> "<signal>"
   | RawHTML s -> Printf.sprintf "\"<raw-html:%d>\"" (String.length s)
diff --git a/hosts/ocaml/transpiler.sx b/hosts/ocaml/transpiler.sx
index 6b44c5a2..d954480b 100644
--- a/hosts/ocaml/transpiler.sx
+++ b/hosts/ocaml/transpiler.sx
@@ -256,6 +256,7 @@
     "callcc-continuation?"
     "callcc-continuation-data"
     "make-callcc-continuation"
+    "callcc-continuation-winders-len"
     "dynamic-wind-call"
     "strip-prefix"
     "component-set-param-types!"
@@ -295,7 +296,8 @@
     "*bind-tracking*"
     "*provide-batch-depth*"
     "*provide-batch-queue*"
-    "*provide-subscribers*"))
+    "*provide-subscribers*"
+    "*winders*"))
 
 (define
   ml-is-mutable-global?
@@ -533,13 +535,13 @@
               "; cf_env = "
               (ef "env")
               "; cf_name = "
-              (if (= frame-type "if") (ef "else") (ef "name"))
+              (if (= frame-type "if") (ef "else") (cond (some (fn (k) (= k "body-result")) items) (ef "body-result") :else (ef "name")))
               "; cf_body = "
               (if (= frame-type "if") (ef "then") (ef "body"))
               "; cf_remaining = "
               (ef "remaining")
               "; cf_f = "
-              (ef "f")
+              (cond (some (fn (k) (= k "after-thunk")) items) (ef "after-thunk") (some (fn (k) (= k "f")) items) (ef "f") :else "Nil")
               "; cf_args = "
               (cond
                 (some (fn (k) (= k "evaled")) items)
@@ -582,6 +584,8 @@
                 (ef "prev-tracking")
                 (some (fn (k) (= k "extra")) items)
                 (ef "extra")
+                (some (fn (k) (= k "winders-len")) items)
+                (ef "winders-len")
                 :else "Nil")
               "; cf_extra2 = "
               (cond