Basic Emacs configuration for Clojure hacking.

init.el

;; Nice way to install packages by jweiss                                                        
(require 'package)                                                                               
(add-to-list 'package-archives                                                                   
             '("marmalade" . "http://marmalade-repo.org/packages/") t)                           
(package-initialize)                                                                             
                                                                                                 
(when (not package-archive-contents)                                                             
  (package-refresh-contents))                                                                    
                                                                                                 
;; Add in your own as you wish:                                                                  
(defvar my-packages '(starter-kit starter-kit-lisp starter-kit-bindings                          
                   clojure-mode ac-nrepl nrepl color-theme rainbow-delimiters auto-complete)            
  "A list of packages to ensure are installed at launch.")                                       
                                                                                                 
(dolist (p my-packages)                                                                          
  (when (not (package-installed-p p))                                                            
    (package-install p))) 

;; Theme selection                                                                               
(eval-after-load "color-theme"
  '(progn                                                                                        
     (color-theme-initialize)
     (color-theme-shaman)))

;; Further tweaks to Clojure mode by jmolet
;; Macro for face definition
(defmacro defcljface (name color desc &optional others)
  `(defface ,name '((((class color)) (:foreground ,color ,@others)))
     ,desc :group 'faces))

;; Define extra clojure faces
(defcljface clojure-keyword      "#45b8f2"   "Clojure keywords")
(defcljface clojure-special      "#0074e8"   "Clojure special")
(defcljface clojure-double-quote "#00920A"   "Clojure special")

;; More syntax coloring
(defun tweak-clojure-syntax (mode)
  (mapcar (λ (x) (font-lock-add-keywords mode x))
          '(((":\\w+" . 'clojure-keyword))
            (("#?\"" 0 'clojure-double-quote prepend))
            (("nil\\|true\\|false\\|%[1-9]?" . 'clojure-special))
            (("\\<\\(FIXME\\|TODO\\|BUG\\):" 1 'font-lock-warning-face t))
            (("(\\(->\\>\\)" 0 (progn (compose-region (match-beginning 1)
                                                      (match-end 1) "→") nil)))
            (("(\\(->>\\>\\)" 0 (progn (compose-region (match-beginning 1)
                                                       (match-end 1) "↠") nil)))
            (("(\\(complement\\>\\)" 0 (progn (compose-region
                                               (match-beginning 1)
                                               (match-end 1) "¬") nil)))
            (("^[a-zA-Z0-9-.*+!_?]+?>" . 'nrepl-prompt-face)))))

(eval-after-load "clojure-mode"
  '(progn
     (tweak-clojure-syntax 'clojure-mode)))

(eval-after-load "nrepl"
  '(progn
     (tweak-clojure-syntax 'nrepl-mode)))

(autoload 'ac-nrepl-setup "ac-nrepl")
(add-hook 'nrepl-mode-hook
          (lambda ()
            (paredit-mode)
            (rainbow-delimiters-mode)
            (auto-complete-mode)
            (ac-nrepl-setup)
            (font-lock-mode nil)
            (clojure-mode-font-lock-setup)
            (font-lock-mode t)))

;; Enable eldoc in clojure buffers
(add-hook 'nrepl-interaction-mode-hook
          (lambda ()
            (nrepl-turn-on-eldoc-mode)))

(eval-after-load "auto-complete"
  '(add-to-list 'ac-modes `nrepl-mode))

;; hide the *nrepl-connection* and *nrepl-server* buffers from appearing in some buffer switching commands
(setq nrepl-hide-special-buffers t)

;; Start the nrepl
(global-set-key (kbd "<f12>") 'repl-jack-in)

;; auto-complete
(autoload 'ac-config-default "auto-complete-config")
(ac-config-default)