+ (let (;; Has this label been defined previously? (Don't read
+ ;; ANSI "2.4.8.15 Sharpsign Equal-Sign" and worry that
+ ;; it requires you to implement forward references,
+ ;; because forward references are disallowed in
+ ;; "2.4.8.16 Sharpsign Sharpsign".)
+ (pair (assoc label *sharp-sharp-alist*)))