#+TITLE:   feature/evil
#+DATE:    February 2, 2017
#+SINCE:   v2.0
#+STARTUP: inlineimages

* Table of Contents :TOC_3:noexport:
- [[Description][Description]]
  - [[Module Flags][Module Flags]]
  - [[Plugins][Plugins]]
  - [[Hacks][Hacks]]
- [[Prerequisites][Prerequisites]]
- [[Features][Features]]
  - [[Ported vim plugins][Ported vim plugins]]
  - [[Custom Text Objects][Custom Text Objects]]
  - [[Custom Ex Commands][Custom Ex Commands]]
  - [[A hybrid code-folding system][A hybrid code-folding system]]
  - [[Differences from vim][Differences from vim]]
- [[Configuration][Configuration]]
  - [[Removing evil-mode][Removing evil-mode]]

* Description
This holy module brings the vim experience to Emacs.

** Module Flags
+ =+everywhere= Enables evilified keybinds everywhere possible, utilizing the
  ~evil-collection~ plugin.

** Plugins
+ [[https://github.com/emacs-evil/evil][evil]]
+ [[https://github.com/wcsmith/evil-args][evil-args]]
+ [[https://github.com/linktohack/evil-commentary][evil-commentary]]
+ [[https://github.com/PythonNut/evil-easymotion][evil-easymotion]]
+ [[https://github.com/cute-jumper/evil-embrace.el][evil-embrace]]
+ [[https://github.com/syl20bnr/evil-escape][evil-escape]]
+ [[https://github.com/Dewdrops/evil-exchange][evil-exchange]]
+ [[https://github.com/TheBB/evil-indent-plus][evil-indent-plus]]
+ [[https://github.com/redguardtoo/evil-matchit][evil-matchit]]
+ [[https://github.com/cofi/evil-numbers][evil-numbers]]
+ [[https://github.com/noctuid/evil-textobj-anyblock][evil-textobj-anyblock]]
+ [[https://github.com/hlissner/evil-snipe][evil-snipe]]
+ [[https://github.com/emacs-evil/evil-surround][evil-surround]]
+ [[https://github.com/alexmurray/evil-vimish-fold][evil-vimish-fold]]
+ [[https://github.com/bling/evil-visualstar][evil-visualstar]]
+ [[https://github.com/ninrod/exato][exato]]
+ [[https://github.com/emacs-evil/evil-collection][evil-collection]]*

** Hacks
+ When a window is split, the new window will be focused.
+ The o/O keys will respect and continue commented lines (can be disabled by
  setting ~+evil-want-o/O-to-continue-comments~ to ~nil~).
+ From visual mode, =*= and =#= will search for the current selection instead of
  the word-at-point.
+ The ~:g[lobal]~ ex command has been modified to highlight matches
  incrementally.
+ More of vim's filename modifiers are supported in ex commands (like ~:p~,
  ~:p:h~ or ~:t~) than vanilla evil-mode offers.
+ A custom filename modifier is available in Doom: ~:P~, which expands to the
  project root (throws an error if not in a project).

* Prerequisites
This module has no external prerequisites.

* Features
** Ported vim plugins
The following vim plugins have been ported to evil:

| Vim Plugin            | Emacs Plugin                   | Keybind(s)          |
|-----------------------+--------------------------------+---------------------|
| vim-commentary        | evil-commentary                | omap =gc=           |
| vim-easymotion        | evil-easymotion                | omap =gs=           |
| vim-seek or vim-sneak | evil-snipe                     | mmap =s=/=S=        |
| vim-surround          | evil-embrace and evil-surround | vmap =S=, omap =ys= |

In other modules:
+ The tools/neotree & tools/treemacs modules contain a =NERDTree= equivalent.
+ The editor/multiple-cursors module contains:
  + ~vim-multiedit~ => evil-multiedit
  + ~vim-multiple-cursors~ => evil-mc

** Custom Text Objects
+ A list of new text objects:
  + Blocks: ~B~ (from ~evil-textobj-anyblock~)
  + Args: ~a~ (from ~evil-args~)
  + Indentation: ~i~ / ~I~ / ~J~ (from ~evil-indent-plus~)

** Custom Ex Commands
| Ex Command           | Description                                                                      |
|----------------------+----------------------------------------------------------------------------------|
| ~:al[ign][!] REGEXP~ | Align text to the first match of REGEXP. If BANG, align all matches on each line |
| ~:mv[!] NEWPATH~     | Move the current file to NEWPATH                                                 |
| ~:cp[!] NEWPATH~     | Copy the current file to NEWPATH                                                 |
| ~:rm[!] [PATH]~      | Delete the current buffer's file and buffer                                      |

** A hybrid code-folding system
This module combines ~vimish-fold~ and ~hideshow~. The former allows arbitrary
folds and the latter allows folds on markers and indentation. Together, they
create a more consistent (and feature-complete) code-folding system.

Most vim folding keys should work, e.g. =zr=, =zm=, =za=, =zo=, etc.

** Differences from vim
+ Column-wise ranges in ex commands are enabled by default. i.e. the range in
  =:'<,'>s/a/b= will only affects the visual selection, not full lines (see
  ~evil-ex-visual-char-range~).
+ =:g= will incrementally highlight buffer matches.

* Configuration
** Removing evil-mode
You must do two things to remove Evil:

1. Remove =:feature evil= from =~/.doom.d/init.el=,
2. Run ~bin/doom refresh~ to clean up lingering dependencies and refresh yuor
   autoloads files.
3. [OPTIONAL] You may want a new ~doom-leader-alt-key~ and
   ~doom-localleader-alt-key~. By default, these are bound to =M-SPC= and =M-SPC
   m=.

#+begin_quote
Ignore ~doom-leader-key~ and ~doom-localleader-key~, they don't apply to
non-evil sessions.
#+end_quote

Note that evil-specific configuration and keybinds (defined with ~map!~) will be
ignored without evil present (and stripped out when byte-compiling).

Unfortunately, since Doom was designed by a vimmer, for vimmers, little
consideration into a keybinding scheme for vanilla Emacs users.