Fix examples.sx: paren balance + dict eval crash at startup

1. Extra closing paren in ex-tabs handler
2. tab-content dict values contained (div ...) HTML tags which crash
   during register_components since HTML primitives aren't in env

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

shared/sx/primitives.py

@@ -561,3 +561,15 @@ def prim_into(target: Any, coll: Any) -> Any:
         return result
     raise ValueError(f"into: unsupported target type {type(target).__name__}")
 
+
+@register_primitive("random-int")
+def prim_random_int(low: int, high: int) -> int:
+    import random
+    return random.randint(int(low), int(high))
+
+
+@register_primitive("json-encode")
+def prim_json_encode(value) -> str:
+    import json
+    return json.dumps(value, indent=2)
+

shared/sx/primitives_io.py

@@ -408,6 +408,18 @@ async def _io_request_form_all(
     return dict(form)
 
 
+@register_io_handler("request-form-list")
+async def _io_request_form_list(
+    args: list[Any], kwargs: dict[str, Any], ctx: RequestContext
+) -> list:
+    """``(request-form-list "field")`` → all values for a multi-value form field."""
+    if not args:
+        raise ValueError("request-form-list requires a field name")
+    from quart import request
+    form = await request.form
+    return form.getlist(str(args[0]))
+
+
 @register_io_handler("request-headers-all")
 async def _io_request_headers_all(
     args: list[Any], kwargs: dict[str, Any], ctx: RequestContext

shared/sx/ref/boundary.sx

@@ -202,6 +202,13 @@
   :doc "All form fields as a dict."
   :context :request)
 
+(define-io-primitive "request-form-list"
+  :params (field-name)
+  :returns "list"
+  :async true
+  :doc "All values for a multi-value form field as a list."
+  :context :request)
+
 (define-io-primitive "request-headers-all"
   :params ()
   :returns "dict"

shared/sx/ref/primitives.sx

@@ -70,6 +70,17 @@
   :doc "Modulo a % b."
   :body (native-mod a b))
 
+(define-primitive "random-int"
+  :params ((low :as number) (high :as number))
+  :returns "number"
+  :doc "Random integer in [low, high] inclusive."
+  :body (native-random-int low high))
+
+(define-primitive "json-encode"
+  :params (value)
+  :returns "string"
+  :doc "Encode value as JSON string with indentation.")
+
 (define-primitive "sqrt"
   :params ((x :as number))
   :returns "number"