path: root/readme.org

#+TITLE: Evil Collection

[[https://github.com/emacs-evil/evil-collection/actions][file:https://github.com/emacs-evil/evil-collection/workflows/build/badge.svg?branch=master]]
[[https://melpa.org/#/evil-collection][file:https://melpa.org/packages/evil-collection-badge.svg]]
[[https://stable.melpa.org/#/evil-collection][file:https://stable.melpa.org/packages/evil-collection-badge.svg]]

This is a collection of [[https://github.com/emacs-evil/evil][Evil]] bindings for /the parts of Emacs/ that Evil does
not cover properly by default, such as ~help-mode~, ~M-x calendar~, Eshell and
more.

*Warning:* Expect some default bindings to change in the future.

** Goals

   1. Reduce context switching: As soon as "moving around" gets hardwired
      to ~<hjkl>~, it becomes frustratingly inefficient not to have it everywhere.

   2. Community work: setting up bindings is tremendous work and joining force can
      only save hours for all of Evil users out there.  While not everyone may agree
      on the chosen bindings, it helps to have something to start with rather than
      nothing at all.  In the end, users are free to override a subset of the proposed
      bindings to best fit their needs.

   3. Consistency: Having all bindings defined in one place allows for enforcing
      consistency across special modes and coordinating the community work to define a
      reference implementation.

** Installation

   - Get the package, either from MELPA:

   : M-x package-install RET evil-collection RET

   Or clone / download this repository and modify your ~load-path~:

   : (add-to-list 'load-path (expand-file-name "/path/to/evil-collection/" user-emacs-directory))

   - Register the bindings, either all at once with

   : (evil-collection-init)

   or mode-by-mode, for instance:

   : (with-eval-after-load 'calendar (evil-collection-calendar-setup))

   or by providing an argument to ~evil-collection-init~:

   : (evil-collection-init 'calendar)

   The list of supported modes is configured by ~evil-collection-mode-list~.

   ~evil-collection~ assumes ~evil-want-keybinding~ is set to nil and
   ~evil-want-integration~ is set to t before loading ~evil~ and
   ~evil-collection.~ Note some other packages may load evil (e.g. evil-leader)
   so bear that in mind when determining when to set the variables.

   See https://github.com/emacs-evil/evil-collection/issues/60 and https://github.com/emacs-evil/evil/pull/1087
   for more details.

   For example:

   #+begin_src emacs-lisp :tangle yes
(setq evil-want-integration t) ;; This is optional since it's already set to t by default.
(setq evil-want-keybinding nil)
(require 'evil)
(when (require 'evil-collection nil t)
  (evil-collection-init))
   #+end_src

   Here's another full TLDR ~use-package~ example.

   #+begin_src emacs-lisp :tangle yes
(use-package evil
  :ensure t
  :init
  (setq evil-want-integration t) ;; This is optional since it's already set to t by default.
  (setq evil-want-keybinding nil)
  :config
  (evil-mode 1))

(use-package evil-collection
  :after evil
  :ensure t
  :config
  (evil-collection-init))
   #+end_src

   NOTE: If you don't like surprises but still want to use ~evil-collection-init~, setting ~evil-collection-mode-list~ to nil
   and adding each mode manually might be a better option.

** Configuration

   Modify ~evil-collection-mode-list~ to disable or add any modes that should be evilified by ~evil-collection~.

   | Variable                                   | Default | Description                                                       |
   |--------------------------------------------+---------+-------------------------------------------------------------------|
   | evil-collection-company-use-tng            | t       | Set up autocompletion to be similar to Vim's YouCompleteMe.       |
   | evil-collection-calendar-want-org-bindings | nil     | Set up Org functions in calendar keymap.                          |
   | evil-collection-outline-bind-tab-p         | nil     | Enable <tab>-based bindings in Outline mode.                      |
   | evil-collection-term-sync-state-and-mode-p | t       | Synchronize insert/normal state with char/line-mode in term-mode. |
   | evil-collection-setup-minibuffer           | nil     | Set up Vim style bindings in the minibuffer.                      |
   | evil-collection-setup-debugger-keys        | t       | Set up debugger keys for certain modes.                           |

   For example, if you want to enable Evil in the minibuffer, you'll have to turn it on
   explicitly by customizing ~evil-collection-setup-minibuffer~ to ~t~.
   Some minibuffer-related packages such as Helm rely on this option.

   ~use-package~ example:

   #+begin_src emacs-lisp :tangle yes
 (use-package evil-collection
   :custom (evil-collection-setup-minibuffer t)
   :init (evil-collection-init))
   #+end_src

** Guidelines

   The following rules serve as guiding principles to define the set of standard
   Evil bindings for various modes.  Since special modes are by definition
   structurally incomparable, those rules cannot be expected to be applied
   universally.

   The rules are more-or-less sorted by priority.

   1. Don't bind anything to ~:~ nor ~<escape>~.

   2. Keep the movement keys when possible and sensible.

      - ~h~, ~j~, ~k~, ~l~
      - ~w~, ~W~, ~b~, ~B~, ~e~, ~E~, ~ge~, ~gE~
      - ~f~, ~F~, ~t~, ~T~, ~;~, =,=
      - ~gg~, ~G~
      - ~|~
      - ~(~, ~)~
      - ~{~, ~}~
      - ~%~
      - ~+~, ~-~, ~0~, ~^~, ~$~
      - ~C-i~, ~C-o~

   3. Keep the yanking and register keys when possible and sensible.

      - ~y~, ~Y~
      - ="=

   4. Keep the search keys when possible and sensible.

      - ~/~, ~?~
      - ~#~, ~*~

   5. Keep the mark keys when possible and sensible.

      - ~m~
      - ='=, =~=

   6. Keep the windowing keys when possible and sensible.

      - ~H~, ~L~, ~M~
      - ~C-e~, ~C-y~
      - ~C-f~, ~C-b~
      - ~C-d~, ~C-u~
      - ~C-w~-prefixed bindings.
      - Some ~z~-prefixed bindings (see below).

   7. The following keys are free when insert state does not make sense in the
      current mode:

      - ~a~, ~A~, ~i~, ~I~
      - ~c~, ~C~, ~r~, ~R~, ~s~, ~S~
      - ~d~, ~D~, ~x~, ~X~
      - ~o~, ~O~
      - ~p~, ~P~
      - ~=~, ~<~, ~>~
      - ~J~
      - =~=

        Any of those keys can be set to be a prefix key.

   8. Prefix keys: ~g~ and ~z~ are the ubiquitous prefix keys.

      - ~g~ generally stands for "go" and is best used for movements.
      - ~z~ is used for scrolling, folding, spell-checking and more.

   9. Macro and action keys

      - ~@~, ~q~
      - ~.~

   10. Ensure terminal compatibility without sacrificing GUI key bindings.

       - Tab key
         - Tab key is recognized as ~<tab>~ in GUI and ~TAB~ in terminal.
           ~TAB~ equals ~C-i~.
         - ~C-i~ is bound to jumping forward for vim compatibility.
           If Shift+Tab is not relevant, just bind ~g TAB~ to the function
           that Tab is bound to. If Shift+Tab is relevant, bind ~g]~ and
           ~g TAB~ to the function that Tab is bound to, and bind ~g[~ to
           the function that Shift+Tab is bound to for terminal compatibility.
       - Enter key
         - Enter key is recognized as ~<return>~ in GUI and ~RET~ in terminal.
           ~RET~ equals ~Ctrl+m~.
         - Bind only ~RET~ and ~M-RET~. Or, bind ~RET~ and ~M-RET~ to the same
           functions ~<return>~ and ~<M-return>~ are bound to.
         - ~S-RET~ is impossible on terminal. Bind ~<S-return>~ and a vacant key
           to the same function for terminal compatibility.

** Rationale

   Many special modes share the same set of similar actions.  Those actions should
   share the same bindings across all modes whenever feasible.

*** Motion (~[~, ~]~, ~{~, ~}~, ~(~, ~)~, ~gj~, ~gk~, ~C-j~, ~C-k~)

    - ~[~ and ~]~: Use ~[-~ and ~]-~ prefixed keys for navigation between sections.

      If the mode makes no difference between the end of a section and the beginning
      of the next, use ~[~ and ~]~.

    - ~gj~ and ~gk~: synonym for ~[~ and ~]~.  That's what [[evilmagit][evil-magit]] does.

    *Question:* Should ~gj~ / ~gk~ rather be synonyms for ~C-j~ / ~C-k~?  They cannot
    emulate the behaviour of ~[]~ or ~][~.

    - ~C-j~, ~C-k~: If there is granularity, i.e. subsections, use ~C-j~ and ~C-k~
      to browse them.  This reflects [[evilmagit][evil-magit]] and [[evilmu4e][evil-mu4e]] default
      bindings.

    - ~{~, ~}~: If there is no paragraph structure, ~{~ and ~}~ can be used for sub-sectioning.

    - ~(~, ~)~: If there is no sentence structure, ~(~ and ~)~ can be used for sub-sectioning.

    - ~HJKL~: ~hjkl~ can be used for atomic movements, but ~HJKL~ can usually not be used
      because ~H~, ~K~ and ~L~ are all universal (~J~ is ~evil-join~ and usually
      does not make sense in special modes).

    - ~C-h~ should not be remapped: Since we have ~C-j~ and ~C-k~ for vertical motion, it would
      make sense to use ~C-h~ and ~C-l~ for horizontal motion.  There are some
      shortcomings though:

      - In Vim, ~C-h~ works as backspace, but Evil does not follow that behaviour.

      - In Emacs, it is a prefix key for all help-related commands, and so is ~<f1>~.

      - Most importantly, ~C-h~ is too widespread and ubiquitous to be replaced.
        So we don't.

    - ~C-l~: As a consequence of the former point, ~C-l~ is available.

    - ~M-<hjkl>~: Those keys are usually free in Evil but still bound to their Emacs
      default (e.g. ~M-l~ is ~downcase-word~).  Besides, if ~C-j~ and ~C-k~ are
      already used, having ~M-j~ and ~M-k~ might add up to the confusion.

*** Quitting (~q~, ~ZQ~, ~ZZ~)

    In Vim, ~q~ is for recording macros.  Vim quits with ~ZZ~ or ~ZQ~.  In most
    Emacs special modes, it stands for quitting while macros are recorded/played
    with ~<f3>~ and ~<f4>~.

    A good rule of thumb would be:

    - Always bind ~q~, ~ZZ~ and ~ZQ~ to the mode specific quitting functions. If there is none,

    - Bind ~q~ and ~ZZ~ to ~quit-window~

    - Bind ~ZQ~ to ~evil-quit~

    - If macros don't make sense in current mode, then ~@~ is available.

*** Refreshing / Reverting (~gr~)

    - ~gr~ is used for refreshing in [[evilmagit][evil-magit]], [[evilmu4e][evil-mu4e]], and some Spacemacs
      configurations (org-agenda and neotree among others).

    ~C-l~ is traditionally used to refresh the terminal screen.  Since there does
    not seem to be any existing use of it, we leave the binding free for other uses.

*** Marking

    ~m~ defaults to ~evil-set-marker~ which might not be very useful in special
    modes.
    ='= can still be used as it can jump to other buffers.

    - ~m~: Mark or toggle mark, depending on what the mode offers.
      In visual mode, always mark.
      With a numeric argument, toggle mark on that many following lines.

    - ~u~: Unmark current selection.

    - ~U~: Unmark all.

    - =~=: Toggle all marks.  This mirrors the "invert-char" Vim command bound to =~=
      by default.

    - ~M~: Mark all, if available.  Otherwise use =U~=.

    - ~*~: Mark-prefix or mark all if current mode has no prefix. ~*~ is traditionally a wildcard.

    - ~%~: Mark regexp.

    - ~x~: Execute action on marks.  This mirrors Dired's binding of ~x~.

    If ~*~ is used for marking, then ~#~ is free.

    Also note that Emacs inconsistently uses ~u~ and ~U~ to unmark.

*** Selecting / Filtering / Narrowing / Searching

    - ~s~ and ~S~ seem to be used in some places like [[mu4e][mu4e]].

      - ~s~: [s]elect/[s]earch/filter candidates according to a pattern.

      - ~S~: Remove filter and select all.

    - ~=~ is usually free and its significance is obvious.  It's taken for zooming though.

    - ~|~ is not free but the pipe symbolic is very tantalizing.

*** Sorting

    - ~o~: Change the sort [o]rder.
    - ~O~: Sort in reverse order.

    There is no real consensus around which key to bind to sorting.  What others do by default:

    - ~package-menu~ uses ~S~.

    - ~M-x proced~ and Dired use ~s~.

    - ~profiler~ uses ~A~ and ~D~.

    - [[mu4e][mu4e]] uses ~O~.

    - [[http://www.nongnu.org/ranger/][ranger]] uses ~o~, inspired from [[http://mutt.org][Mutt]].

*** Go to definition (~gd~, ~gD~)

    - ~gd~: [g]o to [d]efinition.  This is mostly for programming modes.
      If there's a corresponding 'pop' action, use ~C-t~.

*** Go to current entity

    - ~.~: go to current entity (day for calendar, playing track for [[EMMS][EMMS]]).
      Bind only if more relevant than ~evil-repeat~.

*** Open thing at point (~RET~, ~S-RET~, ~M-RET~, ~go~, ~gO~)

    - ~RET~, ~S-RET~, ~M-RET~: Open thing at point in current window, open in other
      window and display in other window respectively.  The latter is like the
      former with the focus remaining on the current window.

    - ~go~, ~gO~: When available, same as ~S-RET~ and ~M-RET~ respectively.  This is
      useful in terminals where ~S-RET~ and ~M-RET~ might not work.

*** Emacs-style jumping (~J~)

    - ~J~: [[mu4e][mu4e]] has ~j~ and [[evil-mu4e][evil-mu4e]] uses ~J~, so we use ~J~ too.

    Some special modes like [[mu4e][mu4e]] and ibuffer offer to "jump" to a different
    buffer.  This sometimes depends on the thing at point.

    This is not related to Evil jumps like ~C-i~ and ~C-o~, nor to "go to
    definition".

*** Browse URL (~gx~)

    ~gx~: go to URL.  This is a default Vim binding.

*** Help (~?~)

    - ~g?~ : is the standard key for help related commands.
    - ~?~ in places where backward search is not very useful.

*** History browsing (~C-n~, ~C-p~)

    ~C-n~ and ~C-p~ are standard bindings to browse the history elements.

*** Bookmarking

    ?

*** REPL (~gz~)
    If the mode has a Go To REPL-type command, set it to ~gz~.
*** Zooming (~+~, ~-~, ~=~, ~0~)

    - ~+~ and ~-~ have obvious meanings.

    - ~0~ has a somewhat intuitive meaning, plus it is next to ~+~ and ~-~ on QWERTY.

    - ~=~ is useful as a synonym for ~+~ because it is the unshifted key of ~+~ on QWERTY.
*** Debugging
    When debugging is on, debugger keys takes the most precedence.

    These keys will be set when there's an available command for them.

    - ~n~ : Step Over
    - ~i~ : Step Into
    - ~o~ : Step Out
    - ~c~ : Continue/Resume Execution
    - ~L~ : Locals
    - ~t~ : Tracing
    - ~q~ : Quit Debugging
    - ~H~ : Continue until Point
    - ~e~ : Evaluate Expression
    - ~b~ : Set Breakpoint
    - ~u~ : Unset Breakpoint
    - ~>~ : Navigate to Next Frame
    - ~<~ : Navigate to Previous Frame
    - ~g?~ : Help
    - ~J~ : Jump to debugger location
    - ~R~ : Restart

    For debugging outside of debugger being on (e.g. setting initial breakpoints),
    we use similar keys to [[https://github.com/realgud/realgud][realgud]].

    - ~f5~ Start/Continue/Resume Execution
    - ~S-f5~ Continue Execution
    - ~Mouse-1~ Toggle Breakpoint
    - ~f9~ Toggle Breakpoint
    - ~f10~ Step Over
    - ~f11~ Step Into
    - ~S-f11~ Step Out
*** Editable Buffers
    For buffers where insert-state doesn't make sense but buffer can be edited,
    (e.g. wdired or wgrep), pressing ~i~ will change into editable state.

    When this editable state is turned on,

    ~ZQ~ will abort and clear any changes.
    ~ZZ~ will finish and save any changes.
    ~ESC~ will exit editable state.
*** :q/:wq/etc
    Modes with commands that can be bound to :q/:wq/etc will have those keys remapped.
** Key Translation
   ~evil-collection-translate-key~ allows binding a key to the definition of
   another key in the same keymap (comparable to how Vim's keybindings work). Its
   arguments are the ~states~ and ~keymaps~ to bind/look up the key(s) in followed
   optionally by keyword arguments (currently only ~:destructive~) and
   key/replacement pairs. ~states~ should be nil for non-evil keymaps, and both
   ~states~ and ~keymaps~ can be a single symbol or a list of symbols.

   This function can be useful for making key swaps/cycles en masse. For example,
   someone who uses an alternate keyboard layout may want to retain the ~hjkl~
   positions for directional movement in dired, the calendar, etc.

   Here's an example for Colemak of making swaps in a single keymap:
   #+begin_src emacs-lisp
(evil-collection-translate-key nil 'evil-motion-state-map
  ;; colemak hnei is qwerty hjkl
  "n" "j"
  "e" "k"
  "i" "l"
  ;; add back nei
  "j" "e"
  "k" "n"
  "l" "i")
   #+end_src

   Here's an example of using ~evil-collection-setup-hook~ to cycle the keys for
   all modes in ~evil-collection-mode-list~:
   #+begin_src emacs-lisp
(defun my-hjkl-rotation (_mode mode-keymaps &rest _rest)
  (evil-collection-translate-key 'normal mode-keymaps
    "n" "j"
    "e" "k"
    "i" "l"
    "j" "e"
    "k" "n"
    "l" "i"))

;; called after evil-collection makes its keybindings
(add-hook 'evil-collection-setup-hook #'my-hjkl-rotation)

(evil-collection-init)
   #+end_src

   A more common use case of ~evil-collection-translate-key~ would be for keeping
   the functionality of some keys that users may bind globally. For example, ~SPC~,
   ~[~, and ~]~ are bound in some modes. If you use these keys as global prefix
   keys that you never want to be overridden, you'll want to give them higher
   priority than other evil keybindings (e.g. those made by ~(evil-define-key
   'normal some-map ...)~). To do this, you can create an "intercept" map and bind
   your prefix keys in it instead of in ~evil-normal-state-map~:
   #+begin_src emacs-lisp
(defvar my-intercept-mode-map (make-sparse-keymap)
  "High precedence keymap.")

(define-minor-mode my-intercept-mode
  "Global minor mode for higher precedence evil keybindings."
  :global t)

(my-intercept-mode)

(dolist (state '(normal visual insert))
  (evil-make-intercept-map
   ;; NOTE: This requires an evil version from 2018-03-20 or later
   (evil-get-auxiliary-keymap my-intercept-mode-map state t t)
   state))

(evil-define-key 'normal my-intercept-mode-map
  (kbd "SPC f") 'find-file)
;; ...
   #+end_src

   You can then define replacement keys:
   #+begin_src emacs-lisp
(defun my-prefix-translations (_mode mode-keymaps &rest _rest)
  (evil-collection-translate-key 'normal mode-keymaps
    "C-SPC" "SPC"
    ;; these need to be unbound first; this needs to be in same statement
    "[" nil
    "]" nil
    "[[" "["
    "]]" "]"))

(add-hook 'evil-collection-setup-hook #'my-prefix-translations)

(evil-collection-init)
   #+end_src

   By default, the first invocation of ~evil-collection-translate-key~ will make a
   backup of the keymap. Each subsequent invocation will look up keys in the backup
   instead of the original. This means that a call to
   ~evil-collection-translate-key~ will always have the same behavior even if
   evaluated multiple times. When ~:destructive t~ is specified, keys are looked up
   in the keymap as it is currently. This means that a call to
   ~evil-collection-translate-key~ that swapped two keys would continue to
   swap/unswap them with each call. Therefore when ~:destructive t~ is used, all
   cycles/swaps must be done within a single call to
   ~evil-collection-translate-key~. To make a comparison to Vim keybindings,
   ~:destructive t~ is comparable to Vim's ~map~, and ~:destructive nil~ is
   comparable to Vim's ~noremap~ (where the "original" keybindings are those that
   existed in the keymap when ~evil-collection-translate-key~ was first called).
   You'll almost always want to use the default behavior (especially in your init
   file). The limitation of ~:destructive nil~ is that you can't translate a key to
   another key that was defined after the first ~evil-collection-translate-key~, so
   ~:destructive t~ may be useful for interactive experimentation.

   ~evil-collection-swap-key~ is also provided as a wrapper around
   ~evil-collection-translate-key~ that allows swapping keys:
   #+begin_src emacs-lisp
(evil-collection-swap-key nil 'evil-motion-state-map
  ";" ":")
;; is equivalent to
(evil-collection-translate-key nil 'evil-motion-state-map
  ";" ":"
  ":" ";")
   #+end_src

** Third-party packages

   Third-party packages are provided by several parties:

   | Major mode | Evil bindings            |
   |------------+--------------------------|
   | lispy      | [[https://github.com/noctuid/lispyville][lispyville]] or [[https://github.com/sp3ctum/evil-lispy][evil-lispy]] |
   | org        | [[https://github.com/GuiltyDolphin/org-evil][org-evil]] or [[https://github.com/Somelauw/evil-org-mode][evil-org]]     |
   | markdown   | [[https://github.com/Somelauw/evil-markdown][evil-markdown]]          |
   | ledger     | [[https://github.com/atheriel/evil-ledger][evil-ledger]]              |

   Should you know any suitable package not mentioned in this list, let us know and
   file an issue.

   Other references:

   - [[https://github.com/syl20bnr/spacemacs/blob/master/doc/CONVENTIONS.org#key-bindings-conventions][Spacemacs]]
   - [[https://github.com/hlissner/doom-emacs/tree/develop/modules/editor/evil][Doom Emacs]]

** FAQ
   - Making SPC work similarly to [[https://github.com/syl20bnr/spacemacs][spacemacs]].

     ~evil-collection~ binds over SPC in many packages. To use SPC as a leader
     key with the [[https://github.com/noctuid/general.el][general]] library:

     #+begin_src emacs-lisp :tangle yes
        (use-package general
          :ensure t
          :init
          (setq general-override-states '(insert
                                          emacs
                                          hybrid
                                          normal
                                          visual
                                          motion
                                          operator
                                          replace))
          :config
          (general-define-key
           :states '(normal visual motion)
           :keymaps 'override
           "SPC" 'hydra-space/body))
           ;; Replace 'hydra-space/body with your leader function.
     #+end_src

     See [[https://github.com/noctuid/evil-guide][noctuid's evil guide]] for other approaches.

   - Unintialized mode maps in ~evil-collection-setup-hook~.
     ~evil-collection-setup-hook~ is ran with a list of keymaps passed into it.
     Some misconfigured modes may not have yet initialized their keymap at this
     time so the value of the variable may be nil. In that case, an alternative
     is to use a mode-hook to do any custom settings.

     #+begin_src emacs-lisp :tangle yes
   (add-hook 'evil-collection-setup-hook
          (lambda (_mode keymaps)
              (add-hook 'ediff-mode-hook
                (lambda ()
                 (... keymaps ...)))))
     #+end_src
     View [[https://github.com/emacs-evil/evil-collection/issues/196][196]] for more info.

** Modes left behind
   Some modes might still remain unsupported by this package.  Should you be
   missing your ~<hjkl>~, please feel free to do a pull request.

** Contributing
   We welcome any additional modes that are not already supported.

   All bindings in ~evil-collection~ are open to change so if there's
   a better or more consistent binding, please [[https://github.com/emacs-evil/evil-collection/issues][open an issue]] or
   [[https://github.com/emacs-evil/evil-collection/pulls][submit a pull request]].

   Follow [[https://github.com/bbatsov/emacs-lisp-style-guide/][The Emacs Lisp Style Guide]] for coding conventions.

   [[https://github.com/erlang/otp/wiki/writing-good-commit-messages][Erlang/OTP]] has a good read for helpful commit messages.

   #+LINK: EMMS https://www.gnu.org/software/emms/
   #+LINK: evilmagit https://github.com/emacs-evil/evil-magit
   #+LINK: evilmu4e https://github.com/JorisE/evil-mu4e
   #+LINK: mu4e https://www.djcbsoftware.nl/code/mu/mu4e.html