Is there an online tool to auto-indent and format Clojure code like there are many for JSON?

Question

There are a lot of tools online that take a JSON text and show you formatted and well indented format of the same.

Some go even further and make a nice tree-like structu

Answer 1

There is now https://github.com/weavejester/cljfmt for that purpose

Instructions

Add it in your Leiningen plugins:

:plugins [[lein-cljfmt "0.6.1"]]

Then, to autoformat all code in your project:

lein cljfmt fix

Sample

Your sample code will become:

(defn prime? [n known] (loop [cnt (dec (count known)) acc []] (if (< cnt 0) (not (any? acc))
                                                                  (recur (dec cnt) (concat acc [(zero? (mod n (nth known cnt)))])))))

After adding some linebreaks and reformatting again:

(defn prime? [n known]
  (loop [cnt (dec (count known)) acc []]
    (if (< cnt 0) (not (any? acc))
        (recur (dec cnt) (concat acc [(zero? (mod n (nth known cnt)))])))))