Clojure and Emacs without Cider redux

2015-02-14 clojure emacs

It’s been a couple of months since I’ve stopped using Cider for Clojure development in Emacs. I find a simple ‘inferior lisp’ setup faster and more reliable. For a good summary of why one would consider not using Cider, see Luke VanderHart’s excellent summary.

There’s been some news in the non-Cider/Emacs/Clojure world since I wrote my last post on the topic. Mainly, the release of inf-clojure by Mr. Batsov himself. I recently switched my Emacs config over to inf-clojure, and it simplified the setup quite a bit. Two additions remain: re-loading of, and switching to, namespaces, and code navigation (with the use of etags). For more details on how to get etags working from Clojure, see here.

This is the current state of my Clojure-related Emacs setup.

;; Clojure
(require 'clojure-mode)
(setq auto-mode-alist (cons '("\\.cljs$" . clojure-mode) auto-mode-alist))

(require 'inf-clojure)
(setq inf-clojure-prompt-read-only nil)
(add-hook 'inf-clojure-minor-mode-hook   ;; prevent company-mode from freezing Emacs when the REPL is busy
          (lambda () (setq completion-at-point-functions nil)))
(add-hook 'clojure-mode-hook 'inf-clojure-minor-mode)

(defun reload-current-clj-ns (next-p)
  (interactive "P")
  (let ((ns (clojure-find-ns)))
    (message (format "Loading %s ..." ns))
    (inf-clojure-eval-string (format "(require '%s :reload)" ns))
    (when (not next-p) (inf-clojure-eval-string (format "(in-ns '%s)" ns)))))

(defun find-tag-without-ns (next-p)
  (interactive "P")
  (find-tag (first (last (split-string (symbol-name (symbol-at-point)) "/")))
            next-p))

(defun erase-inf-buffer ()
  (interactive)
  (with-current-buffer (get-buffer "*inf-clojure*")
    (erase-buffer))
  (inf-clojure-eval-string ""))

(add-hook 'clojure-mode-hook
          '(lambda ()
             (define-key clojure-mode-map "\C-c\C-k" 'reload-current-clj-ns)
             (define-key clojure-mode-map "\M-." 'find-tag-without-ns)
             (define-key clojure-mode-map "\C-cl" 'erase-inf-buffer)
             (define-key clojure-mode-map "\C-c\C-t" 'clojure-toggle-keyword-string)))
(add-hook 'inf-clojure-mode-hook
          '(lambda ()
             (define-key inf-clojure-mode-map "\C-cl" 'erase-inf-buffer)))

;; clj-refactor
(require 'clj-refactor)
(add-hook 'clojure-mode-hook (lambda ()
                               (clj-refactor-mode 1)
                               (cljr-add-keybindings-with-prefix "C-c C-o")))

;; align-cljlet
(require 'align-cljlet)
(add-hook 'clojure-mode-hook
          '(lambda ()
             (define-key clojure-mode-map "\C-c\C-y" 'align-cljlet)))

;; paredit
(require 'paredit)
(add-hook 'clojure-mode-hook 'paredit-mode)

;; projectile
(require 'projectile)
(add-hook 'clojure-mode-hook 'projectile-mode)

;; company-mode
(require 'company)
(require 'company-etags)
(add-to-list 'company-etags-modes 'clojure-mode)
(add-hook 'after-init-hook 'global-company-mode)

;; yasnippet
(require 'yasnippet)
(require 'clojure-snippets)
(yas-global-mode 1)
(add-to-list 'yas-snippet-dirs "~/.emacs.d/snippets")
(yas-load-directory "~/.emacs.d/snippets")