Install Clojure

Install a Java runtime environment, preferably version 1.8 and Leiningen to create, manage and run Clojure projects.

Java

Check you have a Java runtime on your system path by typing the following in a terminal window:

java -version

If Java is not found, please install it from Oracle or OpenJDK.

Java may also be available via your operating systems package manger, for example on Ubuntu / Debian systems this would be installed via:

sudo apt-get install openjdk-8-jre

Leiningen

Leiningen is the most commonly used build automation tool used to manage Clojure projects. Install by saving the Leiningen install script and running it inside a terminal window.

• Install script for Linux & MacOSX
• Install script for Microsoft Windows or use the Linux script from GitBash (recommended).

Save the lein file to somewhere on your operating system path, eg ~/bin

chmod a+x ~/bin/lein
lein

Now run this script on the command line

lein

The first time you run this script it downloads a Java archive file (JAR) of the latest version of Leiningen. When you run the script again, you have a working Leiningen build tool.

Running lein once installed will show you a list of available commands.

Clojure

If you are using Leiningen then there is no specific install for Clojure.

Clojure comes as a library, a JAR file, managed by the build tool Leiningen just like any other dependency.

When you create a project with Leiningen, the configuration is created in a file called project.clj. Inside this project.clj is a dependencies entry where the version of clojure is specified along with any other dependencies. Here is an example of a project.clj configuration with just Clojure as a dependency

(defproject project-name "0.1.0-SNAPSHOT"
  :description "FIXME: write description"
  :url "http://example.com/FIXME"
  :license {:name "Eclipse Public License"
            :url "http://www.eclipse.org/legal/epl-v10.html"}
  :dependencies [[org.clojure/clojure "1.8.0"]])

Hint The Clojure library is very small (~3.6Mb) and Leiningen caches it and all other libraries locally in the same folder structure that Maven uses, eg Clojure version 0.1.8 would be cached in .m2/repository/org/clojure/clojure/1.8.0