HS: E37 tokenizer API (+17 tests)

Implements hs-tokens-of, hs-stream-token, hs-stream-consume,
hs-stream-has-more, hs-token-type, hs-token-value, hs-token-op?,
hs-raw->api-token, hs-eof-sentinel in runtime.sx.

Tokenizer emits whitespace tokens after the first content token;
stream functions skip them for look-ahead and consume. Parser
filters whitespace tokens at hs-parse entry. Dot/hash after close
brackets split into PERIOD/POUND + IDENTIFIER. Template escape \$
produces literal $.

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

lib/hyperscript/compiler.sx

@@ -895,9 +895,15 @@
                             (let
                               ((ch (nth raw i)))
                               (if
-                                (and (= ch "$") (< (+ i 1) n))
+                                (and (= ch "\\") (< (+ i 1) n) (= (nth raw (+ i 1)) "$"))
+                                (do
+                                  (set! buf (str buf "$"))
+                                  (set! i (+ i 2))
+                                  (tpl-collect))
                                 (if
-                                  (= (nth raw (+ i 1)) "{")
+                                  (and (= ch "$") (< (+ i 1) n))
+                                  (if
+                                    (= (nth raw (+ i 1)) "{")
                                   (let
                                     ((start (+ i 2)))
                                     (let
@@ -931,10 +937,10 @@
                                                 (hs-to-sx (hs-compile ident)))))
                                           (set! i end)
                                           (tpl-collect))))))
-                                (do
-                                  (set! buf (str buf ch))
-                                  (set! i (+ i 1))
-                                  (tpl-collect)))))))
+                                  (do
+                                    (set! buf (str buf ch))
+                                    (set! i (+ i 1))
+                                    (tpl-collect))))))))
                       (tpl-collect)
                       (tpl-flush)
                       (cons (quote str) parts))))

lib/hyperscript/parser.sx

@@ -9,7 +9,9 @@
   (fn
     (tokens src)
     (let
-      ((p 0) (tok-len (len tokens)))
+      ((tokens (filter (fn (t) (not (= (get t "type") "whitespace"))) tokens))
+       (p 0)
+       (tok-len (len (filter (fn (t) (not (= (get t "type") "whitespace"))) tokens))))
       (define tp (fn () (if (< p tok-len) (nth tokens p) nil)))
       (define
         tp-type

lib/hyperscript/runtime.sx

@@ -2615,3 +2615,144 @@
               (raise (host-get state "value"))
               (if state (host-get state "value") result)))
           result)))))
+
+(define
+  hs-raw->api-token
+  (fn
+    (raw)
+    (let
+      ((type (dict-get raw :type)) (value (dict-get raw :value)))
+      (cond
+        (= type "ident")
+        {:value value :type "IDENTIFIER" :op false}
+        (= type "keyword")
+        {:value value :type "IDENTIFIER" :op false}
+        (= type "number")
+        {:value value :type "NUMBER" :op false}
+        (= type "string")
+        {:value value :type "STRING" :op false}
+        (= type "class")
+        {:value (str "." value) :type "CLASS_REF" :op false}
+        (= type "id")
+        {:value (str "#" value) :type "ID_REF" :op false}
+        (= type "attr")
+        {:value value :type "ATTRIBUTE_REF" :op false}
+        (= type "style")
+        {:value value :type "STYLE_REF" :op false}
+        (= type "selector")
+        {:value value :type "QUERY_REF" :op false}
+        (= type "eof")
+        {:value "<<<EOF>>>" :type "EOF" :op false}
+        (= type "paren-open")
+        {:value value :type "L_PAREN" :op true}
+        (= type "paren-close")
+        {:value value :type "R_PAREN" :op true}
+        (= type "bracket-open")
+        {:value value :type "L_BRACKET" :op true}
+        (= type "bracket-close")
+        {:value value :type "R_BRACKET" :op true}
+        (= type "brace-open")
+        {:value value :type "L_BRACE" :op true}
+        (= type "brace-close")
+        {:value value :type "R_BRACE" :op true}
+        (= type "comma")
+        {:value value :type "COMMA" :op true}
+        (= type "dot")
+        {:value value :type "PERIOD" :op true}
+        (= type "colon")
+        {:value value :type "COLON" :op true}
+        (= type "op")
+        (cond
+          (= value "+") {:value value :type "PLUS" :op true}
+          (= value "-") {:value value :type "MINUS" :op true}
+          (= value "*") {:value value :type "MULTIPLY" :op true}
+          (= value "/") {:value value :type "SLASH" :op true}
+          (= value "!") {:value value :type "EXCLAMATION" :op true}
+          (= value "?") {:value value :type "QUESTION" :op true}
+          (= value "#") {:value value :type "POUND" :op true}
+          (= value "&") {:value value :type "AMPERSAND" :op true}
+          (= value "=") {:value value :type "EQUALS" :op true}
+          (= value "<") {:value value :type "L_ANG" :op true}
+          (= value ">") {:value value :type "R_ANG" :op true}
+          (= value "<=") {:value value :type "LTE_ANG" :op true}
+          (= value ">=") {:value value :type "GTE_ANG" :op true}
+          (= value "==") {:value value :type "EQ" :op true}
+          (= value "===") {:value value :type "EQQ" :op true}
+          (= value "..") {:value value :type "PERIOD_PERIOD" :op true}
+          :else {:value value :type value :op true})
+        :else {:value (or value "") :type (str type) :op false}))))
+
+(define hs-eof-sentinel {:value "<<<EOF>>>" :type "EOF" :op false})
+
+(define
+  hs-tokens-of
+  (fn
+    (src &rest args)
+    (let
+      ((template (some (fn (a) (equal? a :template)) args)))
+      (let
+        ((raw (if template (hs-tokenize-template src) (hs-tokenize src))))
+        {:pos 0 :list (filter (fn (t) (not (= (dict-get t :type) "EOF"))) (map hs-raw->api-token raw)) :source src}))))
+
+(define
+  hs-stream-token
+  (fn
+    (s i)
+    (let
+      ((lst (dict-get s :list))
+       (n (len (dict-get s :list))))
+      (define
+        find
+        (fn
+          (pos count)
+          (if
+            (>= pos n)
+            hs-eof-sentinel
+            (let
+              ((tok (nth lst pos)))
+              (if
+                (= (dict-get tok :type) "whitespace")
+                (find (+ pos 1) count)
+                (if
+                  (= count 0)
+                  tok
+                  (find (+ pos 1) (- count 1))))))))
+      (find (dict-get s :pos) i))))
+
+(define
+  hs-stream-consume
+  (fn
+    (s)
+    (let
+      ((lst (dict-get s :list))
+       (n (len (dict-get s :list))))
+      (define
+        find-pos
+        (fn
+          (pos)
+          (if
+            (>= pos n)
+            pos
+            (if
+              (= (dict-get (nth lst pos) :type) "whitespace")
+              (find-pos (+ pos 1))
+              pos))))
+      (let
+        ((p (find-pos (dict-get s :pos))))
+        (let
+          ((tok (if (>= p n) hs-eof-sentinel (nth lst p))))
+          (do
+            (when
+              (not (= (dict-get tok :type) "EOF"))
+              (dict-set! s :pos (+ p 1)))
+            tok))))))
+
+(define
+  hs-stream-has-more
+  (fn (s) (not (= (dict-get (hs-stream-token s 0) :type) "EOF"))))
+
+(define hs-token-type (fn (tok) (dict-get tok :type)))
+
+(define hs-token-value (fn (tok) (dict-get tok :value)))
+
+(define hs-token-op? (fn (tok) (dict-get tok :op)))

lib/hyperscript/tokenizer.sx

@@ -465,7 +465,12 @@
         scan!
         (fn
           ()
-          (skip-ws!)
+          (let
+            ((ws-start pos))
+            (skip-ws!)
+            (when
+              (and (> (len tokens) 0) (> pos ws-start))
+              (hs-emit! "whitespace" (slice src ws-start pos) ws-start)))
           (when
             (< pos src-len)
             (let
@@ -489,6 +494,15 @@
                 (do (hs-emit! "selector" (read-selector) start) (scan!))
                 (and (= ch ".") (< (+ pos 1) src-len) (= (hs-peek 1) "."))
                 (do (hs-emit! "op" ".." start) (hs-advance! 2) (scan!))
+                (and
+                  (= ch ".")
+                  (< (+ pos 1) src-len)
+                  (or (hs-letter? (hs-peek 1)) (= (hs-peek 1) "-") (= (hs-peek 1) "_"))
+                  (> (len tokens) 0)
+                  (let
+                    ((lt (dict-get (nth tokens (- (len tokens) 1)) :type)))
+                    (or (= lt "paren-close") (= lt "brace-close") (= lt "bracket-close"))))
+                (do (hs-emit! "dot" "." start) (hs-advance! 1) (scan!))
                 (and
                   (= ch ".")
                   (< (+ pos 1) src-len)
@@ -500,6 +514,15 @@
                   (hs-advance! 1)
                   (hs-emit! "class" (read-class-name pos) start)
                   (scan!))
+                (and
+                  (= ch "#")
+                  (< (+ pos 1) src-len)
+                  (hs-ident-start? (hs-peek 1))
+                  (> (len tokens) 0)
+                  (let
+                    ((lt (dict-get (nth tokens (- (len tokens) 1)) :type)))
+                    (or (= lt "paren-close") (= lt "brace-close") (= lt "bracket-close"))))
+                (do (hs-emit! "op" "#" start) (hs-advance! 1) (scan!))
                 (and
                   (= ch "#")
                   (< (+ pos 1) src-len)