Clojure：使用{：keys [...]}进行结构化和重命名

Question

Is it possible to both destructure and rename keys in one go?

Consider this:

(let [{:keys [response]} {:response 1}]
  (println response))

However, if I want to instead refer to 1 as my-response , I have to do something like:

(let [{:keys [my-response]} (clojure.set/rename-keys {:response 1} {:response :my-response})]
  (println my-response))

Obviously this does not work with defn destructuring.

Is there any way in Clojure to both destructure and rename keys?

Answer 1

Use destructuring without :keys :

(let [{my-response :response} {:response 1}]
  (println my-response))

{:keys [response]} is syntactic sugar for {response :response} .

Answer 2

Here you go:

(let [{:keys [response]} {:response 1}
      my-response response]
   (println my-response))

For a better answer refer to https://stackoverflow.com/a/57592661/2757027 .

This answer is much closer to the question, but technically not single step. but this doesn't involve any complicated de-structuring.

Answer 3

If you don't mind using a library, a more powerful destructuring tool is available from tupelo.core/destruct . Here is an example:

(ns tst.demo.core
  (:use demo.core tupelo.core tupelo.test))

(dotest
  (let [info  {:a 777
               :b [2 3 4]}
        mania [{:a 11} {:b 22} {:c [7 8 9]}]]
    (let [z ::dummy]
      (destruct [info {:a z
                       :b [d e f]}
                 mania [{:a ?} BBB {:c clutter}]]
        (is= z 777)
        (is= [d e f] [2 3 4])
        (is= a 11)
        (is= BBB {:b 22})
        (is= clutter [7 8 9])))))

So you can see that inside the destruct expression, the symbols z , d , e , f , BBB , and clutter are given the corresponding values from the input variables info and mania . The special symbol ? is interpreted to mean that the keyword :a creates a symbol a to receive the value 11 .