It Works!

(all-category-names gcf)
;Value: ("color" "subject" "density" "suds" "color/intensity" "color/hue")

(define gcf2 
'((PICS-version 1.1) ...
 (category  
  (transmit-as "color") ...
  (category  
    (transmit-as "hue") ...
    (category (transmit-as "inside")) ...
  (category  
   (transmit-as "intensity") ...)))))

;Value: "gcf2 --> ((pics-version 1.1) ...)"

(all-category-names gcf2)
;Value: ("color" "subject" "density" "suds"
         "color/intensity" "color/hue" "color/hue/inside")

Jim Miller

http://www.w3.org/