2 Examples top

• link | changes

  user> (sorted-map-by > 1 "a", 2 "b", 3 "c")
  {3 "c", 2 "b", 1 "a"}

  user> (sorted-map-by > 1 "a", 2 "b", 3 "c") {3 "c", 2 "b", 1 "a"}
• link | changes

  ;; If you wish to sort the map according to the values, instead of by keys 
  ;; the following code WILL NOT WORK! This is because the map values are not unique.
  
  user=> (let [results {:A 1 :B 2 :C 2 :D 5 :E 1 :F 1}]
    (into (sorted-map-by (fn [key1 key2]
                           (compare (get results key2)
                                    (get results key1))))
          results))
  
  => {:D 5, :C 2, :A 1}
  
  ;; To make sure that the sorting works, we can make sure that the comparator 
  ;; works on unique values
  
  user=> (let [results {:A 1 :B 2 :C 2 :D 5 :E 1 :F 1}]
    (into (sorted-map-by (fn [key1 key2]
                           (compare [(get results key2) key2]
                                    [(get results key1) key1])))
          results))
  
  => {:D 5, :C 2, :B 2, :F 1, :E 1, :A 1}

  ;; If you wish to sort the map according to the values, instead of by keys ;; the following code WILL NOT WORK! This is because the map values are not unique. user=> (let [results {:A 1 :B 2 :C 2 :D 5 :E 1 :F 1}] (into (sorted-map-by (fn [key1 key2] (compare (get results key2) (get results key1)))) results)) => {:D 5, :C 2, :A 1} ;; To make sure that the sorting works, we can make sure that the comparator ;; works on unique values user=> (let [results {:A 1 :B 2 :C 2 :D 5 :E 1 :F 1}] (into (sorted-map-by (fn [key1 key2] (compare [(get results key2) key2] [(get results key1) key1]))) results)) => {:D 5, :C 2, :B 2, :F 1, :E 1, :A 1}