Returns a string of all elements in collection, as returned by (seq collection), separated by an optional separator.
Following is the syntax.
(join sep col)
Parameters − ‘sep’ is the separator for each element in the collection. ‘col’ is the collection of elements.
Return Value − A joined string.
Following is an example of join in Clojure.
(ns clojure.examples.hello (:gen-class)) (defn hello-world  (println (clojure.string/join ", " [1 2 3]))) (hello-world)
The above program produces the following output.
1 , 2 , 3