comparex.clj

;;all the available sizes as a map with indexes. 
;; ex {:pp 0, :p 1}
(def sizes 
  (apply hash-map 
    (flatten 
      (map-indexed 
        (fn [i s] (list (keyword s) i)) 
        '(pp, p, m, mm, g, gg, a, aa)))))

;; the comparator itself. takes s (the map of available sizes as argument)
;; returns a comparator the uses the supplied s for comparing two itens.
(defn compar [s] 
  (comparator (fn [x y] (< ((keyword x) s) ((keyword y) s)))))

;;sorting
(sort (compar sizes) '(g, a, gg, p))

;;should return 
;;(p g gg a)