#+TITLE: Window numbers for Emacs !

[[https://github.com/syl20bnr/spacemacs][file:https://cdn.rawgit.com/syl20bnr/spacemacs/442d025779da2f62fc86c2082703697714db6514/assets/spacemacs-badge.svg]] [[https://melpa.org/#/winum][file:https://melpa.org/packages/winum-badge.svg]] [[https://stable.melpa.org/#/winum][file:https://stable.melpa.org/packages/winum-badge.svg]]

* Contents :TOC:noexport:
- [[#introduction][Introduction]]
- [[#changelog][Changelog]]
  - [[#sep-11-2019][Sep. 11 2019]]
  - [[#nov-15-2018][Nov. 15 2018]]
  - [[#initial-release-whats-changed-since-window-numbering][Initial release: what's changed since window-numbering]]
- [[#installation][Installation]]
  - [[#using-melpa][Using Melpa]]
  - [[#manual-installation][Manual installation]]
- [[#how-to-use][How to use]]
- [[#configuration][Configuration]]
  - [[#keybindings][Keybindings]]
  - [[#customize-options][Customize options]]
  - [[#configuration-file-example][Configuration file example]]
- [[#future-developments][Future developments]]

* Introduction
Window numbers for Emacs: Navigate your windows and frames using numbers !

This package is an extended and actively maintained version of the
[[https://github.com/nschum/window-numbering.el][window-numbering]] package by Nikolaj Schumacher, with some ideas and code taken
from [[https://github.com/abo-abo/ace-window][ace-window]].

This version brings, among other things, support for number sets across multiple
frames, giving the user a smoother experience of multi-screen Emacs.

* Changelog
** Sep. 11 2019
- Added customize variable =winum-ignored-buffers-regexp= to ignored buffers
  based on regexps.
** Nov. 15 2018
- Added customize variable =winum-format=, a format string to configure how the
  window number appears in the mode-line

** Initial release: what's changed since window-numbering
This package brings a lot of additions to the old window-numbering:

- Number sets across multiple frames, giving a smoother experience of
  multi-screen Emacs
- 3 possible scopes: frame-local, visible frames or all frames
- =get-window-by-number= public function, needed in Spacemacs and for future
  developments.
- Unlimited window numbers
- =select-window-by-number= can now be used interactively to select a window
  using prefix arg or =read-from-minibuffer=, allowing the selection of an
  unlimited number.
- Ignore buffers by name
- =;;;###autoload= all functions that should have public visibility
- Improved =customize= integration
- Removed =window-numbering-before-assign-hook=, which just duplicated
  =window-numbering-assign-func= in a more complicated fashion
- New default key bindings under the ~C-x w~ prefix, to be compliant with Emacs
  key bindings conventions and native Emacs key bindings
- =winum-set-keymap-prefix= helper function to change the prefix more easily
- More detailed README.org
- Improved docstrings
- Simplified implementation for better readability

* Installation
** Using Melpa
The recommended way of installing =winum= is from the [[https://melpa.org/#/winum][Melpa]] package repository:

#+BEGIN_SRC emacs-lisp
M-x package-install RET winum RET
#+END_SRC

You will find instructions to setup Melpa [[https://github.com/melpa/melpa#usage][here]] if you don't have it setup yet.

Once the package is installed, you need to load and activate =winum-mode= in
your Emacs configuration:

#+BEGIN_SRC emacs-lisp
  (require 'winum)

  (winum-mode)
#+END_SRC

** Manual installation
- Clone the repo:

#+BEGIN_SRC shell
  cd /path/to/install/folder
  git clone https://github.com/deb0ch/emacs-winum
#+END_SRC

- Add the following to your Emacs configuration:

#+BEGIN_SRC emacs-lisp
  (add-to-list 'load-path "/path/to/install/folder/emacs-winum/")

  (require 'winum)

  (winum-mode)
#+END_SRC

* How to use
| Key binding | Description                                                                                 |
|-------------+---------------------------------------------------------------------------------------------|
| ~C-x w <n>~ | select window <n>, where <n> ranges from 0 to 9. A negative argument deletes the window.    |
| ~C-x w `~   | select window by number. Number can be given as prefix arg or will be read from minibuffer. |

- =select-window-0-or-10=

  By default, ~C-x w 0~ is bound to =select-window-0-or-10=. If window 0 is not
  assigned, it will act on the window 10 instead.

  You can rebind this to the more straightforward =select-window-0= if you
  prefer.

- =select-window-by-number=

  If you happen to have more than 10 windows, you can use the
  =select-window-by-number= function, bound by default to ~C-x w `~.

  This function allows several ways to input the window number:

  - Use a numbered prefix argument.\\
    *Ex:* ~C-1 C-2 C-x w `~ to select window 12.
  - Use a negative prefix argument to delete the window.\\
    *Ex:* ~C-- C-1 C-2 C-x w `~ to delete window 12.
  - Use the negative prefix argument to delete window 0.\\
    *Ex:* ~C-- C-x w `~ to delete window 0.
  - Use the default prefix argument to delete current window.\\
    *Ex:* ~C-u C-x w `~ to delete current window.
  - If no prefix argument ig given, a number is read from minibuffer. A negative
    input will delete the window instead of selecting it.

* Configuration
** Keybindings
The default prefix for key bindings is ~C-x w~ for compatibility with native
Emacs bindings.

If you don't like ~C-x w~, you can set a prefix of your choosing using the
function =winum-set-keymap-prefix=:

#+BEGIN_SRC elisp
  (winum-set-keymap-prefix (kbd "C-c"))
#+END_SRC

This function overrides the value of =winum-keymap=, so you should call it
before customization of =winum-keymap= and/or after customization of
=winum-base-map=. Its argument must be a key sequence, like the ones returned by
=kbd=.

If you prefer no to use a prefix and have even shorter bindings, you can also
override =winum-keymap= in the minor mode bindings table:

#+BEGIN_SRC emacs-lisp
  (setq winum-keymap
      (let ((map (make-sparse-keymap)))
        (define-key map (kbd "C-`") 'winum-select-window-by-number)
        (define-key map (kbd "C-²") 'winum-select-window-by-number)
        (define-key map (kbd "M-0") 'winum-select-window-0-or-10)
        (define-key map (kbd "M-1") 'winum-select-window-1)
        (define-key map (kbd "M-2") 'winum-select-window-2)
        (define-key map (kbd "M-3") 'winum-select-window-3)
        (define-key map (kbd "M-4") 'winum-select-window-4)
        (define-key map (kbd "M-5") 'winum-select-window-5)
        (define-key map (kbd "M-6") 'winum-select-window-6)
        (define-key map (kbd "M-7") 'winum-select-window-7)
        (define-key map (kbd "M-8") 'winum-select-window-8)
        map))

  (require 'winum)

  (winum-mode)
#+END_SRC

Note that it is important to set =winum-keymap= /before/ the =require=.

You can also use the more conventional =define-key= on =winum-keymap=:

#+BEGIN_SRC emacs-lisp
  (define-key winum-keymap (kbd "C-x y o l o") 'winum-select-window-by-number)
#+END_SRC

*NB:* Both ~`~ and ~²~ are mapped to =winum-select-window-by-number= by default
      to handle both =qwerty= and =azerty= keyboard layouts. If you are using a
      different kind of layout, the recommended place to map it is the key
      beside ~1~.

** Customize options
Several options are available through Emacs' Customize interface under
=convenience= > =winum=:

- =winum-scope=

  Frames affected by a number set. Choices are 'frame-local 'visible or
  'global.

  Default: 'global

- =winum-reverse-frame-list=

  If t, order frames by reverse order of creation. Has effect only when
  =winum-scope= is not 'frame-local.

  Default: =nil=

- =winum-auto-assign-0-to-minibuffer=

  If non-nil, =winum-mode= assigns 0 to the minibuffer if active.

  Default: =t=

- =winum-assign-functions=

  List of functions called for each window by `winum-mode'.

  These functions allow for deterministic assignment of numbers to windows. Each
  function is called for every window. A function should return the number to be
  assigned to a window or nil. The /first/ function to output a number for
  a given window will determine this window's number (if more than 1 function
  assigns a number a warning will be logged in the messages buffer).

  If the list is empty or if every function returns nil for a given window winum
  will proceed to automatic number assignment.

  Since this list is meant to allow custom window assignment for /mutiple/
  packages at once it should never be directly set, only added to and removed
  from.

  These functions, along with ~winum-auto-assign-0-to-minibuffer~, are the only
  way to have 0 assigned to a window.

  Example: always assign *Calculator* the number 9 and *NeoTree* the number 0:

  #+BEGIN_SRC emacs-lisp
    (defun winum-assign-9-to-calculator-8-to-flycheck-errors ()
      (cond
       ((equal (buffer-name) "*Calculator*") 9)
       ((equal (buffer-name) "*Flycheck errors*") 8)))

    (defun winum-assign-0-to-neotree ()
      (when (string-match-p (buffer-name) ".*\\*NeoTree\\*.*") 10))

    (add-to-list 'winum-assign-functions #'winum-assign-9-to-calculator-8-to-flycheck-errors)
    (add-to-list 'winum-assign-functions #'winum-assign-0-to-neotree)
  #+END_SRC

  Default: =nil=

- =winum-auto-setup-mode-line=

  When nil, =winum-mode= will not display window numbers in the mode-line. You
  might want this to be nil if you use a package that already manages window
  numbers in the mode-line.

  Default: =t=

- =winum-format=

  Format string defining how the window number looks like in the mode-line.
  This string is passed to the =format= function along with the result of
  =winum-get-number-string=.

  Default: =" %s "=

- =winum-mode-line-position=

  The position in the mode-line =winum-mode= displays the number.

  Default: =1=

- =winum-ignored-buffers=

  List of buffers to ignore when assigning numbers.

  Default: '(" *which-key*")

- =winum-ignored-buffers-regexp=

  List of regexps for buffer names. Matching buffers will be ignored when
  assigning numbers. See [[https://www.gnu.org/software/emacs/manual/html_node/emacs/Regexps.html][Emacs' documentation on regexps]] for syntax.

  Default: '()

- face: =winum-face=

  Face used for the number in the mode-line.

** Configuration file example
Here is an example that you could put in your =.emacs=, which includes all
available winum options.

#+BEGIN_SRC emacs-lisp
  (setq winum-keymap
      (let ((map (make-sparse-keymap)))
        (define-key map (kbd "C-`") 'winum-select-window-by-number)
        (define-key map (kbd "C-²") 'winum-select-window-by-number)
        (define-key map (kbd "M-0") 'winum-select-window-0-or-10)
        (define-key map (kbd "M-1") 'winum-select-window-1)
        (define-key map (kbd "M-2") 'winum-select-window-2)
        (define-key map (kbd "M-3") 'winum-select-window-3)
        (define-key map (kbd "M-4") 'winum-select-window-4)
        (define-key map (kbd "M-5") 'winum-select-window-5)
        (define-key map (kbd "M-6") 'winum-select-window-6)
        (define-key map (kbd "M-7") 'winum-select-window-7)
        (define-key map (kbd "M-8") 'winum-select-window-8)
        map))

  (require 'winum)

  (defun winum-assign-9-to-calculator-8-to-flycheck-errors ()
    (cond
     ((equal (buffer-name) "*Calculator*") 9)
     ((equal (buffer-name) "*Flycheck errors*") 8)))

  (defun winum-assign-0-to-neotree ()
    (when (string-match-p (buffer-name) ".*\\*NeoTree\\*.*") 10))

  (add-to-list 'winum-assign-functions #'winum-assign-9-to-calculator-8-to-flycheck-errors)
  (add-to-list 'winum-assign-functions #'winum-assign-0-to-neotree)

  (set-face-attribute 'winum-face nil :weight 'bold)

  (setq window-numbering-scope            'global
        winum-reverse-frame-list          nil
        winum-auto-assign-0-to-minibuffer t
        winum-assign-func                 'my-winum-assign-func
        winum-auto-setup-mode-line        t
        winum-format                      " %s "
        winum-mode-line-position          1
        winum-ignored-buffers             '(" *which-key*")
        winum-ignored-buffers-regexp      '(" \\*Treemacs-.*"))

  (winum-mode)
#+END_SRC

* Future developments
- send buffer to numbered window

  Send current window's buffer to window N. With prefix argument focus will
  follow.

- swap buffer with numbered window

  Same as previous, but will swap buffers instead of just sending them.

- Evilify

  Adapt the package to the famous `evil-mode` and use a leader key.

- Override native =other-window= (~C-x o~) to use window numbers

- Autocomplete read-from-minibuffer

- Things that you have thought of and I haven't :smile_cat: