4clojure #69 - Merge with a Function

hyone-4clojure-solution69.clj

;; hyone's solution to Merge with a Function
;; https://4clojure.com/problem/69

(fn my-merge-with [f & maps]
  (reduce
    (fn [a b]
      (reduce
        (fn [x [k v]]
          (assoc x k (if (b k) (f v (b k)) v)))
        b a))
    (first maps) (rest maps)))