build-map.clj

;; ----------clojure beginner question------------
;; Let's say I have a vector of unique values or a
;; set and want to create a map with those as keys
;; and some transformation of them as values.
;; What's the idiomatic way to do this?

;; I'm using the following, but it seems there
;; should be a better way.

(defn build-map [initial-keys map-fn]
  (loop [map {}
         keys (seq initial-keys)]
    (if keys
      (recur (assoc map (first keys)
                    (map-fn (first keys)))
             (next keys))
      map)))


(build-map (range 0 5) (fn [n] (* 10 n)))
;=> {4 40, 3 30, 2 20, 1 10, 0 0}

;; Is there a way to do this with #clj.core/for
;; or something like that?


;; ------------- update ----------------
;; I found an answer:

(into {} (for [n (range 0 5)] [n (* 10 n)]))

;; Much nicer

Found the answer and updated the gist