Step 5.5 phases 1-2: merge sx_scope into sx_primitives, 4-child define support

Phase 1: Absorb sx_scope.ml (180 lines) into sx_primitives.ml. Scope stacks,
cookies, and trace infrastructure now live alongside other primitives. All 20
scope primitive registrations moved. References updated in sx_server.ml and
sx_browser.ml. sx_scope.ml deleted.

Phase 2: Transpiler handles (define name :effects (...) (fn ...)) forms.
ml-emit-define and ml-emit-define-body detect keyword at position 2 and use
(last expr) instead. Unblocks transpilation of spec/render.sx and
web/adapter-html.sx which use 4-child defines extensively.

2598/2598 tests passing.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

hosts/ocaml/bin/sx_server.ml

@@ -140,11 +140,10 @@ let io_batch_mode = ref false
 let io_queue : (int * string * value list) list ref = ref []
 let io_counter = ref 0
 
-(* Scope stacks and cookies — all primitives registered in sx_scope.ml.
+(* Scope stacks and cookies — primitives registered in sx_primitives.ml.
-   We just reference the shared state for the IO bridge. *)
+   We reference the shared state for the IO bridge. *)
-(* Sx_scope accessed directly — library is unwrapped *)
+let _request_cookies = Sx_primitives._request_cookies
-let _request_cookies = Sx_scope.request_cookies
+let _scope_stacks = Sx_primitives._scope_stacks
-let _scope_stacks = Sx_scope.scope_stacks
 
 (* ── App config ─────────────────────────────────────────────────────── *)
 (* Populated from __app-config dict after SX files load.                *)

hosts/ocaml/browser/sx_browser.ml

@@ -50,9 +50,8 @@ let host_get_js (id : int) : Js.Unsafe.any =
 (* Global environment                                                  *)
 (* ================================================================== *)
 
-(* Force module initialization — these modules register primitives
+(* Clear scope stacks at startup *)
-   in their let () = ... blocks but aren't referenced directly. *)
+let () = Sx_primitives.scope_clear_all ()
-let () = Sx_scope.clear_all ()
 
 let global_env = make_env ()
 let _sx_render_mode = ref false
@@ -641,7 +640,7 @@ let () =
   (* --- Scope stack --- *)
   (* Scope primitives (scope-push!, scope-pop!, context, collect!, collected,
      emit!, emitted, scope-emit!, scope-emitted, etc.) are registered by
-     Sx_scope module initialization in the primitives table.
+     Sx_primitives module initialization in the primitives table.
      The CEK evaluator falls through to the primitives table when a symbol
      isn't in the env, so these work automatically.
      Only provide-push!/provide-pop! need explicit env bindings as aliases. *)
@@ -921,11 +920,11 @@ let () =
 
   (* Scope tracing API *)
   Js.Unsafe.set sx (Js.string "scopeTraceOn") (Js.wrap_callback (fun () ->
-    Sx_scope.scope_trace_enable (); Js.Unsafe.inject Js.null));
+    Sx_primitives.scope_trace_enable (); Js.Unsafe.inject Js.null));
   Js.Unsafe.set sx (Js.string "scopeTraceOff") (Js.wrap_callback (fun () ->
-    Sx_scope.scope_trace_disable (); Js.Unsafe.inject Js.null));
+    Sx_primitives.scope_trace_disable (); Js.Unsafe.inject Js.null));
   Js.Unsafe.set sx (Js.string "scopeTraceDrain") (Js.wrap_callback (fun () ->
-    let log = Sx_scope.scope_trace_drain () in
+    let log = Sx_primitives.scope_trace_drain () in
     Js.Unsafe.inject (Js.array (Array.of_list (List.map (fun s -> Js.Unsafe.inject (Js.string s)) log)))));
 
   Js.Unsafe.set Js.Unsafe.global (Js.string "SxKernel") sx

hosts/ocaml/lib/sx_primitives.ml

@@ -14,6 +14,29 @@ let _sx_trampoline_fn : (value -> value) ref =
   ref (fun v -> v)
 let _is_client : bool ref = ref false
 
+(** Scope stacks — dynamic scope for render-time effects.
+    Each key maps to a stack of values. Used by aser for
+    spread/provide/emit patterns, CSSX collect/flush, etc.
+    Migrated from sx_scope.ml. *)
+let _scope_stacks : (string, value list) Hashtbl.t = Hashtbl.create 8
+
+(** Debug trace for scope operations *)
+let _scope_trace = ref false
+let _scope_log : string list ref = ref []
+let scope_trace_enable () = _scope_trace := true; _scope_log := []
+let scope_trace_disable () = _scope_trace := false
+let scope_trace_drain () =
+  let log = List.rev !_scope_log in
+  _scope_log := [];
+  log
+
+(** Request cookies — set by the Python bridge before each render.
+    get-cookie reads from here; set-cookie is a no-op on the server. *)
+let _request_cookies : (string, string) Hashtbl.t = Hashtbl.create 8
+
+(** Clear all scope stacks. Called between requests if needed. *)
+let scope_clear_all () = Hashtbl.clear _scope_stacks
+
 let register name fn = Hashtbl.replace primitives name fn
 
 let is_primitive name = Hashtbl.mem primitives name
@@ -976,4 +999,155 @@ let () =
        | Some fn -> fn []
        | None -> raise (Eval_error ("VM undefined: " ^ name)))
     | _ -> raise (Eval_error "call-primitive: expected (name args-list)"));
-  ()
+  ();
+
+  (* ================================================================ *)
+  (* Scope stacks — dynamic scope for render-time effects.            *)
+  (* Migrated from sx_scope.ml — Phase 1 of step 5.5                 *)
+  (* ================================================================ *)
+
+  (* --- Cookies --- *)
+
+  register "get-cookie" (fun args ->
+    match args with
+    | [String name] ->
+      (match Hashtbl.find_opt _request_cookies name with
+       | Some v -> String v
+       | None -> Nil)
+    | _ -> Nil);
+
+  register "set-cookie" (fun _args -> Nil);
+
+  (* --- Core scope stack operations --- *)
+
+  register "scope-push!" (fun args ->
+    match args with
+    | [String name; value] ->
+      let stack = try Hashtbl.find _scope_stacks name with Not_found -> [] in
+      if !_scope_trace then
+        _scope_log := Printf.sprintf "PUSH %s depth=%d->%d" name (List.length stack) (List.length stack + 1) :: !_scope_log;
+      Hashtbl.replace _scope_stacks name (value :: stack); Nil
+    | _ -> Nil);
+
+  register "scope-pop!" (fun args ->
+    match args with
+    | [String name] ->
+      let stack = try Hashtbl.find _scope_stacks name with Not_found -> [] in
+      if !_scope_trace then
+        _scope_log := Printf.sprintf "POP %s depth=%d->%d" name (List.length stack) (max 0 (List.length stack - 1)) :: !_scope_log;
+      (match stack with _ :: rest -> Hashtbl.replace _scope_stacks name rest | [] -> ()); Nil
+    | _ -> Nil);
+
+  register "scope-peek" (fun args ->
+    match args with
+    | [String name] ->
+      let stack = try Hashtbl.find _scope_stacks name with Not_found -> [] in
+      if !_scope_trace then
+        _scope_log := Printf.sprintf "PEEK %s depth=%d found=%b" name (List.length stack) (stack <> []) :: !_scope_log;
+      (match stack with v :: _ -> v | [] -> Nil)
+    | _ -> Nil);
+
+  (* --- Context (scope lookup with optional default) --- *)
+
+  register "context" (fun args ->
+    match args with
+    | (String name) :: rest ->
+      let stack = try Hashtbl.find _scope_stacks name with Not_found -> [] in
+      if !_scope_trace then
+        _scope_log := Printf.sprintf "CTX %s depth=%d found=%b" name (List.length stack) (stack <> []) :: !_scope_log;
+      (match stack with
+       | v :: _ -> v
+       | [] -> (match rest with default_val :: _ -> default_val | [] -> Nil))
+    | _ -> Nil);
+
+  register "context-debug" (fun args ->
+    match args with
+    | [String name] ->
+      let stack = try Hashtbl.find _scope_stacks name with Not_found -> [] in
+      let all_keys = Hashtbl.fold (fun k _ acc -> k :: acc) _scope_stacks [] in
+      String (Printf.sprintf "name=%s stack_len=%d all_keys=[%s]"
+        name (List.length stack) (String.concat "," all_keys))
+    | _ -> String "bad args");
+
+  (* --- Collect / collected / clear-collected! --- *)
+
+  register "collect!" (fun args ->
+    match args with
+    | [String name; value] ->
+      let stack = try Hashtbl.find _scope_stacks name with Not_found -> [] in
+      (match stack with
+       | List items :: rest ->
+         if not (List.mem value items) then
+           Hashtbl.replace _scope_stacks name (List (items @ [value]) :: rest)
+       | [] ->
+         Hashtbl.replace _scope_stacks name [List [value]]
+       | _ :: _ -> ());
+      Nil
+    | _ -> Nil);
+
+  register "collected" (fun args ->
+    match args with
+    | [String name] ->
+      let stack = try Hashtbl.find _scope_stacks name with Not_found -> [] in
+      (match stack with List items :: _ -> List items | _ -> List [])
+    | _ -> List []);
+
+  register "clear-collected!" (fun args ->
+    match args with
+    | [String name] ->
+      let stack = try Hashtbl.find _scope_stacks name with Not_found -> [] in
+      (match stack with
+       | _ :: rest -> Hashtbl.replace _scope_stacks name (List [] :: rest)
+       | [] -> Hashtbl.replace _scope_stacks name [List []]);
+      Nil
+    | _ -> Nil);
+
+  (* --- Emit / emitted --- *)
+
+  register "scope-emit!" (fun args ->
+    match args with
+    | [String name; value] ->
+      let stack = try Hashtbl.find _scope_stacks name with Not_found -> [] in
+      (match stack with
+       | List items :: rest ->
+         Hashtbl.replace _scope_stacks name (List (items @ [value]) :: rest)
+       | Nil :: rest ->
+         Hashtbl.replace _scope_stacks name (List [value] :: rest)
+       | [] ->
+         Hashtbl.replace _scope_stacks name [List [value]]
+       | _ :: _ -> ());
+      Nil
+    | _ -> Nil);
+
+  register "emit!" (fun args ->
+    match Hashtbl.find_opt primitives "scope-emit!" with
+    | Some fn -> fn args | None -> Nil);
+
+  register "emitted" (fun args ->
+    match args with
+    | [String name] ->
+      let stack = try Hashtbl.find _scope_stacks name with Not_found -> [] in
+      (match stack with List items :: _ -> List items | _ -> List [])
+    | _ -> List []);
+
+  register "scope-emitted" (fun args ->
+    match Hashtbl.find_opt primitives "emitted" with
+    | Some fn -> fn args | None -> List []);
+
+  register "scope-collected" (fun args ->
+    match Hashtbl.find_opt primitives "collected" with
+    | Some fn -> fn args | None -> List []);
+
+  register "scope-clear-collected!" (fun args ->
+    match Hashtbl.find_opt primitives "clear-collected!" with
+    | Some fn -> fn args | None -> Nil);
+
+  (* --- Provide aliases --- *)
+
+  register "provide-push!" (fun args ->
+    match Hashtbl.find_opt primitives "scope-push!" with
+    | Some fn -> fn args | None -> Nil);
+
+  register "provide-pop!" (fun args ->
+    match Hashtbl.find_opt primitives "scope-pop!" with
+    | Some fn -> fn args | None -> Nil)

hosts/ocaml/lib/sx_scope.ml

@@ -1,180 +0,0 @@
-(** Scope stacks — dynamic scope for render-time effects.
-
-    Provides scope-push!/pop!/peek, collect!/collected/clear-collected!,
-    scope-emit!/emitted/scope-emitted, context, and cookie access.
-
-    All functions are registered as primitives so both the CEK evaluator
-    and the JIT VM can find them in the same place. *)
-
-open Sx_types
-
-(** The shared scope stacks hashtable. Each key maps to a stack of values.
-    Used by aser for spread/provide/emit patterns, CSSX collect/flush, etc. *)
-let scope_stacks : (string, value list) Hashtbl.t = Hashtbl.create 8
-
-(** Debug trace for scope operations — enabled from JS *)
-let _scope_trace = ref false
-let _scope_log : string list ref = ref []
-let scope_trace_enable () = _scope_trace := true; _scope_log := []
-let scope_trace_disable () = _scope_trace := false
-let scope_trace_drain () =
-  let log = List.rev !_scope_log in
-  _scope_log := [];
-  log
-
-(** Request cookies — set by the Python bridge before each render.
-    get-cookie reads from here; set-cookie is a no-op on the server. *)
-let request_cookies : (string, string) Hashtbl.t = Hashtbl.create 8
-
-(** Clear all scope stacks. Called between requests if needed. *)
-let clear_all () = Hashtbl.clear scope_stacks
-
-let () =
-  let register = Sx_primitives.register in
-
-  (* --- Cookies --- *)
-
-  register "get-cookie" (fun args ->
-    match args with
-    | [String name] ->
-      (match Hashtbl.find_opt request_cookies name with
-       | Some v -> String v
-       | None -> Nil)
-    | _ -> Nil);
-
-  register "set-cookie" (fun _args -> Nil);
-
-  (* --- Core scope stack operations --- *)
-
-  register "scope-push!" (fun args ->
-    match args with
-    | [String name; value] ->
-      let stack = try Hashtbl.find scope_stacks name with Not_found -> [] in
-      if !_scope_trace then
-        _scope_log := Printf.sprintf "PUSH %s depth=%d->%d" name (List.length stack) (List.length stack + 1) :: !_scope_log;
-      Hashtbl.replace scope_stacks name (value :: stack); Nil
-    | _ -> Nil);
-
-  register "scope-pop!" (fun args ->
-    match args with
-    | [String name] ->
-      let stack = try Hashtbl.find scope_stacks name with Not_found -> [] in
-      if !_scope_trace then
-        _scope_log := Printf.sprintf "POP %s depth=%d->%d" name (List.length stack) (max 0 (List.length stack - 1)) :: !_scope_log;
-      (match stack with _ :: rest -> Hashtbl.replace scope_stacks name rest | [] -> ()); Nil
-    | _ -> Nil);
-
-  register "scope-peek" (fun args ->
-    match args with
-    | [String name] ->
-      let stack = try Hashtbl.find scope_stacks name with Not_found -> [] in
-      if !_scope_trace then
-        _scope_log := Printf.sprintf "PEEK %s depth=%d found=%b" name (List.length stack) (stack <> []) :: !_scope_log;
-      (match stack with v :: _ -> v | [] -> Nil)
-    | _ -> Nil);
-
-  (* --- Context (scope lookup with optional default) --- *)
-
-  register "context" (fun args ->
-    match args with
-    | (String name) :: rest ->
-      let stack = try Hashtbl.find scope_stacks name with Not_found -> [] in
-      if !_scope_trace then
-        _scope_log := Printf.sprintf "CTX %s depth=%d found=%b" name (List.length stack) (stack <> []) :: !_scope_log;
-      (match stack with
-       | v :: _ -> v
-       | [] -> (match rest with default_val :: _ -> default_val | [] -> Nil))
-    | _ -> Nil);
-
-  register "context-debug" (fun args ->
-    match args with
-    | [String name] ->
-      let stack = try Hashtbl.find scope_stacks name with Not_found -> [] in
-      let all_keys = Hashtbl.fold (fun k _ acc -> k :: acc) scope_stacks [] in
-      String (Printf.sprintf "name=%s stack_len=%d all_keys=[%s]"
-        name (List.length stack) (String.concat "," all_keys))
-    | _ -> String "bad args");
-
-  (* --- Collect / collected / clear-collected! --- *)
-
-  register "collect!" (fun args ->
-    match args with
-    | [String name; value] ->
-      let stack = try Hashtbl.find scope_stacks name with Not_found -> [] in
-      (match stack with
-       | List items :: rest ->
-         if not (List.mem value items) then
-           Hashtbl.replace scope_stacks name (List (items @ [value]) :: rest)
-       | [] ->
-         Hashtbl.replace scope_stacks name [List [value]]
-       | _ :: _ -> ());
-      Nil
-    | _ -> Nil);
-
-  register "collected" (fun args ->
-    match args with
-    | [String name] ->
-      let stack = try Hashtbl.find scope_stacks name with Not_found -> [] in
-      (match stack with List items :: _ -> List items | _ -> List [])
-    | _ -> List []);
-
-  register "clear-collected!" (fun args ->
-    match args with
-    | [String name] ->
-      let stack = try Hashtbl.find scope_stacks name with Not_found -> [] in
-      (match stack with
-       | _ :: rest -> Hashtbl.replace scope_stacks name (List [] :: rest)
-       | [] -> Hashtbl.replace scope_stacks name [List []]);
-      Nil
-    | _ -> Nil);
-
-  (* --- Emit / emitted (for spread attrs in adapter-html.sx) --- *)
-
-  register "scope-emit!" (fun args ->
-    match args with
-    | [String name; value] ->
-      let stack = try Hashtbl.find scope_stacks name with Not_found -> [] in
-      (match stack with
-       | List items :: rest ->
-         Hashtbl.replace scope_stacks name (List (items @ [value]) :: rest)
-       | Nil :: rest ->
-         Hashtbl.replace scope_stacks name (List [value] :: rest)
-       | [] ->
-         Hashtbl.replace scope_stacks name [List [value]]
-       | _ :: _ -> ());
-      Nil
-    | _ -> Nil);
-
-  register "emit!" (fun args ->
-    (* Alias for scope-emit! *)
-    match Sx_primitives.get_primitive "scope-emit!" with
-    | NativeFn (_, fn) -> fn args | _ -> Nil);
-
-  register "emitted" (fun args ->
-    match args with
-    | [String name] ->
-      let stack = try Hashtbl.find scope_stacks name with Not_found -> [] in
-      (match stack with List items :: _ -> List items | _ -> List [])
-    | _ -> List []);
-
-  register "scope-emitted" (fun args ->
-    match Sx_primitives.get_primitive "emitted" with
-    | NativeFn (_, fn) -> fn args | _ -> List []);
-
-  register "scope-collected" (fun args ->
-    match Sx_primitives.get_primitive "collected" with
-    | NativeFn (_, fn) -> fn args | _ -> List []);
-
-  register "scope-clear-collected!" (fun args ->
-    match Sx_primitives.get_primitive "clear-collected!" with
-    | NativeFn (_, fn) -> fn args | _ -> Nil);
-
-  (* --- Provide aliases --- *)
-
-  register "provide-push!" (fun args ->
-    match Sx_primitives.get_primitive "scope-push!" with
-    | NativeFn (_, fn) -> fn args | _ -> Nil);
-
-  register "provide-pop!" (fun args ->
-    match Sx_primitives.get_primitive "scope-pop!" with
-    | NativeFn (_, fn) -> fn args | _ -> Nil)

hosts/ocaml/transpiler.sx

@@ -1712,7 +1712,8 @@
     (expr)
     (let
       ((name (if (= (type-of (nth expr 1)) "symbol") (symbol-name (nth expr 1)) (str (nth expr 1))))
-        (val-expr (nth expr 2)))
+        (val-expr
+          (let ((raw (nth expr 2))) (if (keyword? raw) (last expr) raw))))
       (let
         ((ml-name (ml-mangle name))
           (is-fn
@@ -1825,7 +1826,8 @@
     (expr)
     (let
       ((name (if (= (type-of (nth expr 1)) "symbol") (symbol-name (nth expr 1)) (str (nth expr 1))))
-        (val-expr (nth expr 2)))
+        (val-expr
+          (let ((raw (nth expr 2))) (if (keyword? raw) (last expr) raw))))
       (let
         ((ml-name (ml-mangle name))
           (is-fn