Automate Clojure projects without setting your hair on fire.
"Leiningen!" he shouted. "You're insane! They're not creatures you can fight—they're an elemental—an 'act of God!' Ten miles long, two miles wide—ants, nothing but ants! And every single one of them a fiend from hell..." - from Leiningen Versus the Ants by Carl Stephenson
Leiningen is for automating Clojure projects without setting your hair on fire.
If your preferred package manager offers a recent version of Leiningen, try that first as long as it has version 2.x.
Leiningen installs itself on the first run of the
leinshell script; there is no separate install script. Follow these instructions to install Leiningen manually:
leinscript from the
stablebranch of this project.
~/binis a good choice if it is on your path.)
chmod +x ~/bin/lein)
The tutorial has a detailed walk-through of the steps involved in creating a new project, but here are the commonly-used tasks:
$ lein new [TEMPLATE] NAME # generate a new project skeleton
$ lein test [TESTS] # run the tests in the TESTS namespaces, or all tests
$ lein repl # launch an interactive REPL session
$ lein run -m my.namespace # run the -main function of a namespace
$ lein uberjar # package the project and dependencies as standalone jar
$ lein deploy clojars # publish the project to Clojars as a library
lein helpto see a complete list.
lein help $TASKshows the usage for a specific task.
You can also chain tasks together in a single command by using the
dotask with comma-separated tasks:
$ lein do clean, test foo.test-core, jar
Most tasks need to be run from somewhere inside a project directory to work, but some (
repl) may run from anywhere.
project.cljfile in the project root should look like this:
(defproject myproject "0.5.0-SNAPSHOT" :description "A project for doing things." :license "Eclipse Public License 1.0" :url "http://github.com/technomancy/myproject" :dependencies [[org.clojure/clojure "1.8.0"]] :plugins [[lein-tar "3.2.0"]])
lein newtask generates a project skeleton with an appropriate starting point from which you can work. See the sample.project.clj file (also available via
lein help sample) for a detailed listing of configuration options.
project.cljfile can be customized further with the use of profiles.
Leiningen documentation is organized as a number of guides:
Leiningen supports plugins which may introduce new tasks. See the plugins wiki page for a full list. If a plugin is needed for successful test or build runs, (such as
lein-tar) then it should be added to
:pluginsin project.clj, but if it's for your own convenience (such as
lein-pprint) then it should be added to the
:pluginslist in the
~/.lein/profiles.clj. See the profiles guide for details on how to add to your
:userprofile. The plugin guide explains how to write plugins.
Source Copyright © 2009-2021 Phil Hagelberg, Alex Osborne, Dan Larkin, and contributors. Distributed under the Eclipse Public License, the same as Clojure uses. See the file COPYING.
Thanks to Stuart Halloway for Lancet and Tim Dysinger for convincing me that good builds are important.
Images Copyright © 2010 Phil Hagelberg. Distributed under the Creative Commons Attribution + ShareAlike License 4.0. Full-size version available.