HS toggle style: parse between/cycle, runtime, mock style dict

Parser:
- Reorder toggle style parsing: target before between clause
- Handle "indexed" keyword, "indexed by" syntax
- Use parse-atom (not parse-expr) for between values to avoid
  consuming "and" as boolean operator
- Support 3-4 value cycles via toggle-style-cycle

Compiler:
- Add toggle-style-cycle dispatch → hs-toggle-style-cycle!

Runtime:
- Add hs-toggle-style-between! (2-value toggle)
- Add hs-toggle-style-cycle! (N-value round-robin)

Mock DOM:
- Parse CSS strings from setAttribute "style" into style sub-dict
  so dom-get-style/dom-set-style work correctly

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

hosts/ocaml/bin/run_tests.ml

@@ -1815,6 +1815,22 @@ let run_spec_tests env test_files =
                 Hashtbl.replace d "className" (String sv);
               end;
               if name = "disabled" then Hashtbl.replace d "disabled" (Bool true);
+              if name = "style" then begin
+                (* Parse CSS string into the style sub-dict *)
+                let style_d = match Hashtbl.find_opt d "style" with Some (Dict s) -> s | _ ->
+                  let s = Hashtbl.create 4 in Hashtbl.replace d "style" (Dict s); s in
+                let parts = String.split_on_char ';' sv in
+                List.iter (fun part ->
+                  let part = String.trim part in
+                  if String.length part > 0 then
+                    match String.index_opt part ':' with
+                    | Some i ->
+                      let prop = String.trim (String.sub part 0 i) in
+                      let value = String.trim (String.sub part (i+1) (String.length part - i - 1)) in
+                      Hashtbl.replace style_d prop (String value)
+                    | None -> ()
+                ) parts
+              end;
               Nil
             | _ -> Nil)
          | "getAttribute" ->

lib/hyperscript/compiler.sx

@@ -1008,6 +1008,14 @@
                   (nth ast 1)
                   (hs-to-sx (nth ast 2))
                   (hs-to-sx (nth ast 3))))
+              ((= head (quote toggle-style-cycle))
+                (list
+                  (quote hs-toggle-style-cycle!)
+                  (hs-to-sx (nth ast 2))
+                  (nth ast 1)
+                  (cons
+                    (quote list)
+                    (map hs-to-sx (slice ast 3 (len ast))))))
               ((= head (quote toggle-attr))
                 (list
                   (quote hs-toggle-attr!)

lib/hyperscript/parser.sx

@@ -935,40 +935,64 @@
                     (list (quote toggle-class) cls tgt)))))
             ((= (tp-type) "style")
               (let
-                ((prop (do (let ((v (tp-val))) (adv!) v))))
+                ((prop (get (adv!) "value")))
-                (if
+                (let
-                  (match-kw "between")
+                  ((tgt (if (match-kw "of") (parse-expr) (list (quote me)))))
-                  (let
+                  (if
-                    ((val1 (parse-atom)))
+                    (match-kw "between")
-                    (expect-kw! "and")
                     (let
-                      ((val2 (parse-atom)))
+                      ((val1 (parse-atom)))
+                      (expect-kw! "and")
                       (let
-                        ((tgt (parse-tgt-kw "on" (list (quote me)))))
+                        ((val2 (parse-atom)))
-                        (list (quote toggle-style-between) prop val1 val2 tgt))))
+                        (if
-                  (let
+                          (match-kw "and")
-                    ((tgt (parse-tgt-kw "on" (list (quote me)))))
+                          (let
+                            ((val3 (parse-atom)))
+                            (if
+                              (match-kw "and")
+                              (let
+                                ((val4 (parse-atom)))
+                                (list
+                                  (quote toggle-style-cycle)
+                                  prop
+                                  tgt
+                                  val1
+                                  val2
+                                  val3
+                                  val4))
+                              (list
+                                (quote toggle-style-cycle)
+                                prop
+                                tgt
+                                val1
+                                val2
+                                val3)))
+                          (list
+                            (quote toggle-style-between)
+                            prop
+                            val1
+                            val2
+                            tgt))))
                     (list (quote toggle-style) prop tgt)))))
             ((= (tp-type) "attr")
               (let
-                ((attr-name (do (let ((v (tp-val))) (adv!) v))))
+                ((attr-name (get (adv!) "value")))
-                (if
+                (let
-                  (match-kw "between")
+                  ((tgt (if (match-kw "on") (parse-expr) (list (quote me)))))
-                  (let
+                  (if
-                    ((val1 (parse-atom)))
+                    (match-kw "between")
-                    (expect-kw! "and")
                     (let
-                      ((val2 (parse-atom)))
+                      ((val1 (parse-expr)))
+                      (expect-kw! "and")
                       (let
-                        ((tgt (parse-tgt-kw "on" (list (quote me)))))
+                        ((val2 (parse-expr)))
                         (list
                           (quote toggle-attr-between)
                           attr-name
                           val1
                           val2
-                          tgt))))
+                          tgt)))
-                  (let
-                    ((tgt (parse-tgt-kw "on" (list (quote me)))))
                     (list (quote toggle-attr) attr-name tgt)))))
             ((and (= (tp-type) "keyword") (= (tp-val) "my"))
               (do

lib/hyperscript/runtime.sx

@@ -99,6 +99,39 @@
 ;; ── Navigation / traversal ──────────────────────────────────────
 
 ;; Navigate to a URL.
+(define
+  hs-toggle-style-between!
+  (fn
+    (target prop val1 val2)
+    (let
+      ((cur (dom-get-style target prop)))
+      (if
+        (= cur val1)
+        (dom-set-style target prop val2)
+        (dom-set-style target prop val1)))))
+
+;; Find next sibling matching a selector (or any sibling).
+(define
+  hs-toggle-style-cycle!
+  (fn
+    (target prop vals)
+    (let
+      ((cur (dom-get-style target prop)))
+      (define
+        find-next
+        (fn
+          (remaining)
+          (cond
+            ((empty? remaining) (first vals))
+            ((= cur (first remaining))
+              (if
+                (empty? (rest remaining))
+                (first vals)
+                (first (rest remaining))))
+            (true (find-next (rest remaining))))))
+      (dom-set-style target prop (find-next vals)))))
+
+;; Find previous sibling matching a selector.
 (define
   hs-take!
   (fn
@@ -122,7 +155,7 @@
               (dom-set-attr target name attr-val)
               (dom-set-attr target name ""))))))))
 
-;; Find next sibling matching a selector (or any sibling).
+;; First element matching selector within a scope.
 (define
   hs-put!
   (fn
@@ -135,7 +168,7 @@
       ((= pos "start") (dom-insert-adjacent-html target "afterbegin" value))
       ((= pos "end") (dom-insert-adjacent-html target "beforeend" value)))))
 
-;; Find previous sibling matching a selector.
+;; Last element matching selector.
 (define
   hs-add-to!
   (fn
@@ -145,7 +178,7 @@
       (append target (list value))
       (host-call target "push" value))))
 
-;; First element matching selector within a scope.
+;; First/last within a specific scope.
 (define
   hs-remove-from!
   (fn
@@ -155,16 +188,18 @@
       (filter (fn (x) (not (= x value))) target)
       (host-call target "splice" (host-call target "indexOf" value) 1))))
 
-;; Last element matching selector.
 (define
   hs-set-on!
   (fn
     (props target)
     (for-each (fn (k) (host-set! target k (get props k))) (keys props))))
 
-;; First/last within a specific scope.
+;; ── Iteration ───────────────────────────────────────────────────
+
+;; Repeat a thunk N times.
 (define hs-navigate! (fn (url) (perform (list (quote io-navigate) url))))
 
+;; Repeat forever (until break — relies on exception/continuation).
 (define
   hs-scroll!
   (fn
@@ -177,9 +212,10 @@
           ((= position "bottom") (dict :block "end"))
           (true (dict :block "start")))))))
 
-;; ── Iteration ───────────────────────────────────────────────────
+;; ── Fetch ───────────────────────────────────────────────────────
 
-;; Repeat a thunk N times.
+;; Fetch a URL, parse response according to format.
+;; (hs-fetch url format) — format is "json" | "text" | "html"
 (define
   hs-halt!
   (fn
@@ -189,19 +225,23 @@
       (host-call event "preventDefault" (list))
       (when (= mode "event") (host-call event "stopPropagation" (list))))))
 
-;; Repeat forever (until break — relies on exception/continuation).
-(define hs-select! (fn (target) (host-call target "select" (list))))
-
-;; ── Fetch ───────────────────────────────────────────────────────
-
-;; Fetch a URL, parse response according to format.
-;; (hs-fetch url format) — format is "json" | "text" | "html"
-(define hs-reset! (fn (target) (host-call target "reset" (list))))
-
 ;; ── Type coercion ───────────────────────────────────────────────
 
 ;; Coerce a value to a type by name.
 ;; (hs-coerce value type-name) — type-name is "Int", "Float", "String", etc.
+(define hs-select! (fn (target) (host-call target "select" (list))))
+
+;; ── Object creation ─────────────────────────────────────────────
+
+;; Make a new object of a given type.
+;; (hs-make type-name) — creates empty object/collection
+(define hs-reset! (fn (target) (host-call target "reset" (list))))
+
+;; ── Behavior installation ───────────────────────────────────────
+
+;; Install a behavior on an element.
+;; A behavior is a function that takes (me ...params) and sets up features.
+;; (hs-install behavior-fn me ...args)
 (define
   hs-next
   (fn
@@ -221,10 +261,10 @@
               (true (find-next (dom-next-sibling el))))))
         (find-next sibling)))))
 
-;; ── Object creation ─────────────────────────────────────────────
+;; ── Measurement ─────────────────────────────────────────────────
 
-;; Make a new object of a given type.
+;; Measure an element's bounding rect, store as local variables.
-;; (hs-make type-name) — creates empty object/collection
+;; Returns a dict with x, y, width, height, top, left, right, bottom.
 (define
   hs-previous
   (fn
@@ -244,27 +284,18 @@
               (true (find-prev (dom-get-prop el "previousElementSibling"))))))
         (find-prev sibling)))))
 
-;; ── Behavior installation ───────────────────────────────────────
-
-;; Install a behavior on an element.
-;; A behavior is a function that takes (me ...params) and sets up features.
-;; (hs-install behavior-fn me ...args)
-(define
-  hs-query-all
-  (fn (sel) (host-call (dom-body) "querySelectorAll" sel)))
-
-;; ── Measurement ─────────────────────────────────────────────────
-
-;; Measure an element's bounding rect, store as local variables.
-;; Returns a dict with x, y, width, height, top, left, right, bottom.
-(define
-  hs-query-first
-  (fn (sel) (host-call (host-global "document") "querySelector" sel)))
-
 ;; ── Transition ──────────────────────────────────────────────────
 
 ;; Transition a CSS property to a value, optionally with duration.
 ;; (hs-transition target prop value duration)
+(define
+  hs-query-all
+  (fn (sel) (host-call (dom-body) "querySelectorAll" sel)))
+
+(define
+  hs-query-first
+  (fn (sel) (host-call (host-global "document") "querySelector" sel)))
+
 (define
   hs-query-last
   (fn
@@ -410,6 +441,10 @@
       ((or (string? a) (string? b)) (str a b))
       (true (+ a b)))))
 
+
+
+
+
 (define
   hs-make
   (fn
@@ -422,15 +457,12 @@
       (true (dict)))))
 
 (define hs-install (fn (behavior-fn) (behavior-fn me)))
-
+;; ── Sandbox/test runtime additions ──────────────────────────────
-
+;; Property access — dot notation and .length
-
-
-
 (define
   hs-measure
   (fn (target) (perform (list (quote io-measure) target))))
-
+;; DOM query stub — sandbox returns empty list
 (define
   hs-transition
   (fn
@@ -443,8 +475,7 @@
         (str prop " " (/ duration 1000) "s")))
     (dom-set-style target prop value)
     (when duration (hs-settle target))))
-;; ── Sandbox/test runtime additions ──────────────────────────────
+;; Method dispatch — obj.method(args)
-;; Property access — dot notation and .length
 (define
   hs-transition-from
   (fn
@@ -458,7 +489,9 @@
         (str prop " " (/ duration 1000) "s")))
     (dom-set-style target prop (str to-val))
     (when duration (hs-settle target))))
-;; DOM query stub — sandbox returns empty list
+
+;; ── 0.9.90 features ─────────────────────────────────────────────
+;; beep! — debug logging, returns value unchanged
 (define
   hs-type-check
   (fn
@@ -478,33 +511,31 @@
             (= (host-typeof value) "element")
             (= (host-typeof value) "text")))
         (true (= (host-typeof value) (downcase type-name)))))))
-;; Method dispatch — obj.method(args)
+;; Property-based is — check obj.key truthiness
 (define
   hs-type-check-strict
   (fn
     (value type-name)
     (if (nil? value) false (hs-type-check value type-name))))
-
+;; Array slicing (inclusive both ends)
-;; ── 0.9.90 features ─────────────────────────────────────────────
-;; beep! — debug logging, returns value unchanged
 (define
   hs-strict-eq
   (fn (a b) (and (= (type-of a) (type-of b)) (= a b))))
-;; Property-based is — check obj.key truthiness
+;; Collection: sorted by
 (define
   hs-eq-ignore-case
   (fn (a b) (= (downcase (str a)) (downcase (str b)))))
-;; Array slicing (inclusive both ends)
+;; Collection: sorted by descending
 (define
   hs-starts-with-ic?
   (fn (str prefix) (starts-with? (downcase str) (downcase prefix))))
-;; Collection: sorted by
+;; Collection: split by
 (define
   hs-contains-ignore-case?
   (fn
     (haystack needle)
     (contains? (downcase (str haystack)) (downcase (str needle)))))
-;; Collection: sorted by descending
+;; Collection: joined by
 (define
   hs-falsy?
   (fn
@@ -516,7 +547,7 @@
       ((and (list? v) (= (len v) 0)) true)
       ((= v 0) true)
       (true false))))
-;; Collection: split by
+
 (define
   hs-matches?
   (fn
@@ -527,7 +558,7 @@
       ((= (host-typeof target) "element")
         (if (string? pattern) (host-call target "matches" pattern) false))
       (true false))))
-;; Collection: joined by
+
 (define
   hs-contains?
   (fn