cl: Phase 1 lambda-list parser + 31 tests (172 total green)

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

lib/common-lisp/parser.sx

@@ -227,6 +227,124 @@
                   (get item "rest")
                   (concat acc (list (get item "form"))))))))))))
 
+;; ── lambda-list parser ───────────────────────────────────────────
+;;
+;; (cl-parse-lambda-list forms) — parse a list of CL forms (already read)
+;; into a structured dict:
+;;   {:required (list sym ...)
+;;    :optional (list {:name N :default D :supplied S} ...)
+;;    :rest     nil | "SYM"
+;;    :key      (list {:name N :keyword K :default D :supplied S} ...)
+;;    :allow-other-keys false | true
+;;    :aux      (list {:name N :init I} ...)}
+;;
+;; Symbols arrive as SX strings (upcase). &-markers are strings like "&OPTIONAL".
+;; Key params: keyword is the upcase name string; caller uses it as :keyword.
+;; Supplied-p: nil when absent.
+
+(define
+  cl-parse-opt-spec
+  (fn
+    (spec)
+    (if
+      (list? spec)
+      {:name (nth spec 0)
+        :default (if (> (len spec) 1) (nth spec 1) nil)
+        :supplied (if (> (len spec) 2) (nth spec 2) nil)}
+      {:name spec :default nil :supplied nil})))
+
+(define
+  cl-parse-key-spec
+  (fn
+    (spec)
+    (if
+      (list? spec)
+      (let
+        ((first (nth spec 0)))
+        (if
+          (list? first)
+          ;; ((:keyword var) default supplied-p)
+          {:name (nth first 1)
+            :keyword (get first "name")
+            :default (if (> (len spec) 1) (nth spec 1) nil)
+            :supplied (if (> (len spec) 2) (nth spec 2) nil)}
+          ;; (var default supplied-p)
+          {:name first
+            :keyword first
+            :default (if (> (len spec) 1) (nth spec 1) nil)
+            :supplied (if (> (len spec) 2) (nth spec 2) nil)}))
+      {:name spec :keyword spec :default nil :supplied nil})))
+
+(define
+  cl-parse-aux-spec
+  (fn
+    (spec)
+    (if
+      (list? spec)
+      {:name (nth spec 0) :init (if (> (len spec) 1) (nth spec 1) nil)}
+      {:name spec :init nil})))
+
+(define
+  cl-parse-lambda-list
+  (fn
+    (forms)
+    (let
+      ((state "required")
+        (required (list))
+        (optional (list))
+        (rest-name nil)
+        (key (list))
+        (allow-other-keys false)
+        (aux (list)))
+
+      (define
+        scan
+        (fn
+          (items)
+          (when
+            (> (len items) 0)
+            (let
+              ((item (nth items 0)) (tail (rest items)))
+              (cond
+                ((= item "&OPTIONAL")
+                  (do (set! state "optional") (scan tail)))
+                ((= item "&REST")
+                  (do (set! state "rest") (scan tail)))
+                ((= item "&BODY")
+                  (do (set! state "rest") (scan tail)))
+                ((= item "&KEY")
+                  (do (set! state "key") (scan tail)))
+                ((= item "&AUX")
+                  (do (set! state "aux") (scan tail)))
+                ((= item "&ALLOW-OTHER-KEYS")
+                  (do (set! allow-other-keys true) (scan tail)))
+                ((= state "required")
+                  (do (append! required item) (scan tail)))
+                ((= state "optional")
+                  (do (append! optional (cl-parse-opt-spec item)) (scan tail)))
+                ((= state "rest")
+                  (do (set! rest-name item) (set! state "done") (scan tail)))
+                ((= state "key")
+                  (do (append! key (cl-parse-key-spec item)) (scan tail)))
+                ((= state "aux")
+                  (do (append! aux (cl-parse-aux-spec item)) (scan tail)))
+                (:else (scan tail)))))))
+
+      (scan forms)
+      {:required required
+        :optional optional
+        :rest rest-name
+        :key key
+        :allow-other-keys allow-other-keys
+        :aux aux})))
+
+;; Convenience: parse lambda list from a CL source string
+(define
+  cl-parse-lambda-list-str
+  (fn
+    (src)
+    (cl-parse-lambda-list (cl-read src))))
+
 ;; ── public API ────────────────────────────────────────────────────
 
 (define