Evil

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Evil is an extensible vi layer for Emacs. It provides Vim features like Visual selection and text objects, and is the successor to the now defunct vimpulse and vim-mode.

Quick install

Evil comes prebuilt in emacs24. In Emacs23, Evil can be downloaded and installed using el-get with: M-x el-get-install RET evil RET.

Download

Alternatively, Evil lives in a Git repository. To download Evil, do:

git clone git://gitorious.org/evil/evil.git

If you don't have Git, just head over to Gitorious and click the "Download master as tar.gz" link (extract with ##tar -xzf master.tar.gz##).

Install

If you installed it manually, move Evil to ~/.emacs.d/evil (or somewhere else in your ##load-path##). In any case, add the following lines to ~/.emacs:

(add-to-list 'load-path "~/.emacs.d/evil") ;;no need with 24
(require 'evil)
(evil-mode 1)


Evil requires [UndoTree undo-tree.el] in the load-path for linear undo and undo branches. Otherwise, Evil uses regular Emacs undo.

Documentation

A brief PDF manual is available in the /doc subdirectory.

Configuration

One thing I would recommend to any ex vimmer is to make escape to quit actually pretty much anything (like pending prompts in the minibuffer):

   ;;; esc quits
   (define-key evil-normal-state-map [escape] 'keyboard-quit)
   (define-key evil-visual-state-map [escape] 'keyboard-quit)
   (define-key minibuffer-local-map [escape] 'minibuffer-keyboard-quit)
   (define-key minibuffer-local-ns-map [escape] 'minibuffer-keyboard-quit)
   (define-key minibuffer-local-completion-map [escape] 'minibuffer-keyboard-quit)
   (define-key minibuffer-local-must-match-map [escape] 'minibuffer-keyboard-quit)
   (define-key minibuffer-local-isearch-map [escape] 'minibuffer-keyboard-quit)

The following makes you loose vim commands, but gives you back basic emacs commands, like C-y to paste in insert mode or C-r to search backward:

   (define-key evil-normal-state-map "\C-y" 'yank)
   (define-key evil-insert-state-map "\C-y" 'yank)
   (define-key evil-visual-state-map "\C-y" 'yank)
   (define-key evil-insert-state-map "\C-e" 'end-of-line)
   (define-key evil-normal-state-map "\C-w" 'evil-delete)
   (define-key evil-insert-state-map "\C-w" 'evil-delete)
   (define-key evil-insert-state-map "\C-r" 'search-backward)
   (define-key evil-visual-state-map "\C-w" 'evil-delete)


In insert mode, Evil uses linear undo. If you want fine grain undo:

   (setq evil-want-fine-undo t)

but remember, we shouldn't stay long in insert mode.

If you'd like to type jj or jk in insert mode to go back to normal mode, you may use key-chord:

   (key-chord-define evil-insert-state-map "jj" 'evil-normal-state)

Note: I still load evil with M-x, I didn't set (evil-mode 1), so in order to tweak keybindings I had to enclose them in a hook, so that my config is called when evil is called:

   (add-hook 'evil-after-load-hook
         (lambda ()
         ;; config
    ))

Hooks

There are some hooks that allow to do things when we enter or exit a mode (see the pdf manual).

For example, to save the buffer when we exit the insert mode:

   (defun my-save-if-bufferfilename ()
     (if (buffer-file-name)
         (progn
           (save-buffer)
           )
       (message "no file is associated to this buffer: do nothing")
       )
   )
   (add-hook 'evil-insert-state-exit-hook 'my-save-if-bufferfilename)

Enter an emacs mode in a given state

There are some situations where you don't want to be in normal mode by default. For example, it's more useful to be in insert mode when we enter a magit commit buffer, or maybe you prefer to be in emacs mode in a dired buffer.

For that purpose, evil provides the `evil-set-initial-state` command (see part 2.2 of the pdf documentation) that we can use like that:

(evil-set-initial-state 'git-commit-mode 'insert) ;; enter insert mode to edit a commit message

Here is a handy loop to define more at once:

    (loop for (mode . state) in '((inferior-emacs-lisp-mode . emacs)
                              (nrepl-mode . insert)
                              (pylookup-mode . emacs)
                              (comint-mode . normal)
                              (shell-mode . insert)
                              (git-commit-mode . insert)
                              (git-rebase-mode . emacs)
                              (term-mode . emacs)
                              (help-mode . emacs)
                              (helm-grep-mode . emacs)
                              (grep-mode . emacs)
                              (bc-menu-mode . emacs)
                              (magit-branch-manager-mode . emacs)
                              (rdictcc-buffer-mode . emacs)
                              (dired-mode . emacs)
                              (wdired-mode . normal))
      do (evil-set-initial-state mode state))

Articles

Plug-ins

Bug tracker

The bugtrucker can be found on Bitbucket.