Emacs, Clojure, and Windows 7

Okay, I had to wrestle with this. Maybe that makes me dumb, but if you're reading this, then you ain't doin' much better. I've had an on-and-off again, love/hate relationship with emacs over the years, and I'm swinging back to "on/love" while dinking around with Clojure. Emacs really is the best Lisp-type environment, even on Windows.

To give credit where due, I started with this good post on freegeek.in, but some bits were outdated.

Pre-requisites

First, get emacs installed. Find the latest version in this folder, and extract it someplace - no installation is really necessary.

You also need git. Let's assume you get through all of that.

Last, but not least, you should have a JDK installed.

Add the path to git and java.exe to your PATH, and set JAVA_HOME to your JDK. If you don't want to do that, then start a command prompt, set them manually, and do anything emacs-y from there.

set PATH=%PATH%;c:\sys\git\bin;c:\sys\emacs-23.1\bin
set JAVA_HOME=c:\program files\Java\jdk1.6.0_19
runemacs

Emacs Starter Kit

Next, install the Emacs Starter Kit. This is a huge time-saver. Many of my previous complaints about emacs tended to be having to learn so much just to modify the environment. This takes care of a majority of that. One of the nice, and really important bits is ELPA - a package management system for emacs. In one fell swoop, 80% of my complaints have been silenced.

Anyway, download the ESK from github

git clone git://github.com/eschulte/emacs-starter-kit.git C:\Users\<userdirectory>\AppData\Roaming\.emacs.d

If you have a C:\Users\<userdirectory>\AppData\Roaming\.emacs file, rename it. You can copy it to custom.el, and it will be used as normal. Most of the action occurs in init.el, so that's a good place to look if you really don't like something.

Nope, we're not quite there yet. Before you can use it, you need to install org-mode.

cd C:\Users\<userdirectory>\AppData\Roaming\.emacs.d
git submodule init
git submodule update

Fire up emacs, and M-x package-list-packages. Scroll right on by that tempting "clojure-mode", and put your cursor on "swank-clojure", then press "i" (to select it for installation), then "x" (to start the installation).

---

Okay, here's where I ran into a problem: when trying to use ELPA, I got the following error: "Local variables entry is missing the suffix". The nice thing about obscure error messages is that they are usually pretty easy to search on. (There's a patch here, only the file name is "package.el"

You'll be adding a function, and modifying package-unpack-singe to use it.

(defun package-write-file-no-coding (file-name excl) 
 (setq buffer-file-coding-system 'no-conversion) 
 (write-region (point-min) (point-max) file-name nil nil nil excl))

The ESK instructions say to build org-mode after that, but launching emacs seemed to take care of that.

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Using it

Woooo! Installed! Isn't this easier than NetBeans? (well, actually "yes" for me, since it was some frustration with Enclojure that drove me back to emacs)

Launch emacs, and type M-x slime. If you have everything set up right, you should be prompted to install clojure. This will not only install clojure, but also get you the swank-clojure.jar you'll be needing for projects.

Projects

Assuming you got your SLIME prompt in the step before, creating a project is easy, but not as easy as it could be.

Create the following directory structure wherever it is you want your project to go:

root
  +--src
  +--lib
  +--classes

In the lib directory, put your clojure, clojure-contrib, and swank-clojure jars. You can find them in C:\Users\<username>\AppData\Roaming\.swank-clojure Then you should be able to start a new project with:

M-x swank-clojure-project

That should do it - hope it helps