Question

我只是想在Clojure中重命名地图功能，以便更好地接触任意输入。我写的函数有传递的args数量的问题。即，

(defn new-map [f [& x]]
      (map f x))

此外，最终目标是编写一个可以处理嵌套输入的映射函数：

输入1：[inc [[1 2 3] [4 5]] [2 1]]

输出1：[[1 2 3] [5 5]]其中inc是特定函数f，[[1 2 3] [4 5]]是一个数组，[2 1]首先选出第二行数组的元素。

输入2：[inc [[1 2 3] [4 5] [6] [7]] [[1 1] [2 2] [3]]]

输出2：[[2 2 3] [4 6] [7] [7]]

Answer 1

听起来你希望reduce与update-in

即

(defn new-map [f nested-vecs indices]
  (reduce (fn [nv idxs] (update-in nv idxs f))
          nested-vecs
          indices))

;; I changed your inputs. Remember that indices start from 0
(new-map inc [[1 2 3] [4 5] [6] [7]] [[0 0] [1 1] [2 0]])

; => [[2 2 3] [4 6] [7] [7]]

扩展map函数以处理嵌套段

1 个答案: