#+title: Emacs configuration
#+author: Aryadev Chavali
#+description: My Emacs configuration
#+property: header-args:emacs-lisp :tangle config.el :comments link :results none
#+startup: noindent
#+options: toc:t num:t
#+latex_header:\usepackage[margin=1.0in]{geometry}
#+latex_class: article
#+latex_class_options: [a4paper,12pt]

* Introduction
:PROPERTIES:
:header-args:emacs-lisp: :tangle config.el :results none
:END:
Welcome to my Emacs configuration.  You may be confused by the fact
it's a readable document with prose rather than just code; this file
serves as both documentation *and* code.  The essential idea is that I
can explain my ideas in prose then provide the code as a block.

Here's an example of some Emacs Lisp code:
#+begin_src emacs-lisp
;;; config.el --- Compiled configuration from config.org  -*- lexical-binding: t; -*-

;; Copyright (C) 2024  Aryadev Chavali

;; Author: Aryadev Chavali <aryadev@aryadevchavali.com>

;; This program is distributed in the hope that it will be useful, but WITHOUT
;; ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
;; FOR A PARTICULAR PURPOSE.  See the MIT License for details.

;; You may distribute and modify this code under the terms of the MIT License,
;; which you should have received a copy of along with this program.  If not,
;; please go to <https://opensource.org/license/MIT>.

;;; Commentary:
;; Welcome to my Emacs configuration.  This file is considered volatile i.e. any
;; edits made to this file will be overwritten if and when the configuration is
;; compiled.

;; To propagate edits from this file back to the literate document, call
;; (org-babel-detangle).
;;; Code:
#+end_src

This is an Emacs Lisp code block, something you will see a *LOT* of
throughout.  All the Emacs Lisp code blocks in this document are
collected, concatenated then written to a file (=config.el=).  This
code file is then evaluated by Emacs
[[file:init.el::+literate/load-config][at boot]].

This style of coding is called /literate programming/.  Donald Knuth
[[https://en.wikipedia.org/wiki/Literate_programming][really liked]]
the idea.  I mainly utilise this to explain my decisions for
configuring or using certain packages: Emacs is an opinionated piece
of software after all.

Sections tagged =WAIT= are not compiled and are, hence, unused.
Usually I provide some reasoning as to why.  Such sections can be
easily placed back into the configuration and in Emacs can be loaded
at runtime when I need them, which is why they're not deleted.  A lot
of code here is essentially write and forget; nothing needs to change
unless I find a more efficient way to do things.

Some sections border on blog posts justifying why I think they're good
applications or giving some greater reasoning about my specific
configuration of a package.  That can be distracting, so tangling this
file (via ~(org-babel-tangle)~) and looking at the source code may be
more helpful.
* Basics
Let's setup a few things:
+ My name and mail address
+ File encoding
+ Backup files (~backup-directory-alist~)
+ Refreshing buffers when a change occurs (~auto-revert-mode~)
+ Yes or no questions being less painful (~y-or-n-p~)
+ Make the kill ring work seamlessly with the clipboard

#+begin_src emacs-lisp
(use-package emacs
  :demand t
  :init
  (setq user-full-name "Aryadev Chavali"
        user-mail-address "aryadev@aryadevchavali.com"
        buffer-file-coding-system 'utf-8-unix
        save-buffer-coding-system 'utf-8-unix
        backup-directory-alist `(("." . ,(no-littering-expand-var-file-name "saves/")))
        global-auto-revert-non-file-buffers t
        auto-revert-verbose nil
        auto-revert-use-notify nil
        select-enable-clipboard t)
  :config
  (fset 'yes-or-no-p 'y-or-n-p)
  (global-auto-revert-mode))
#+end_src
* Custom functionality
This is custom Lisp I've written to help me out throughout the
configuration.  Note that because it's setup so early I can use it
throughout the file.
** Procedure
An anonymous function (~lambda~) which takes no arguments is a
procedure.  This macro generates procedures, with the parameters of
the macro being the body of the procedure.  It returns it in quoted
form, as that is the most common use of this macro.

#+begin_src emacs-lisp
(defmacro proc (&rest BODY)
  "For a given list of forms BODY, return a quoted 0 argument
lambda."
  `(quote (lambda nil ,@BODY)))
#+end_src
** Automatically run a command on saving
Define a macro which creates hooks into ~after-save-hook~.  On certain
~conditions~ being met, ~to-run~ is evaluated.
#+begin_src emacs-lisp
(use-package simple
  :defer t
  :config
  (defmacro +oreo/create-auto-save (conditions &rest to-run)
    "Create a hook for after saves, where on CONDITIONS being met
TO-RUN is evaluated."
    `(add-hook 'after-save-hook
               (proc
                (interactive)
                (when ,conditions ,@to-run)))))
#+end_src
** System specificity
A macro that acts as a switch case on ~(system-name)~ so a user can
write code for multiple hosts.  For me this is for my desktop and
laptop.  Though there may be an easier solution than this, this seems
simple enough.

Note the check for the symbol ~otherwise~ which acts as the default
case.
#+begin_src emacs-lisp
(defmacro system-name-cond (&rest pairs)
  "Switch case on result of function `system-name'.

Each pair in PAIRS is typed as: (string . (forms...)) where the
string represents the system name to test, and forms being the
consequence if true. if string is the symbol OTHERWISE, then it
is considered the default case."
  `(cond ,@(mapcar
            #'(lambda (pair)
                (cl-destructuring-bind (name . body) pair
                  (if (eq name 'otherwise)
                      `(t ,@body)
                    `((string= (system-name) ,name) ,@body))))
            pairs)))
#+end_src
*** Setting number of native jobs
In [[file:early-init.el][early-init.el]] I set the number of
native-workers to 4, which isn't necessarily optimal when
loading/compiling the rest of this file depending on the machine I
use:
- On my laptop (=newboy=) I'd prefer to have it use 2-3 threads so
  I can actually use the rest of the laptop while waiting for
  compilation
- On my desktop (=oldboy=) I'd prefer to use 4-6 threads as I can
  afford more, so I can get a faster load up.
#+begin_src emacs-lisp
(use-package comp
  :init
  (setq native-comp-async-jobs-number
        (system-name-cond
         ("newboy" 3)
         ("oldboy" 6)
         (otherwise 3))))
#+end_src
** Clean buffer list
Clean all buffers except for those in ~+oreo/keep-buffers~.
#+begin_src emacs-lisp
(defconst +oreo/keep-buffers
  (list "config.org" "*scratch*"
        "*dashboard*" "*Messages*"
        "*Warnings*" "*eshell*")
  "List of buffer names to preserve.")

(defun +oreo/clean-buffers ()
  "Kill all buffers except any with names in +oreo/keep-buffers."
  (interactive)
  (let ((should-not-kill #'(lambda (buf) (member (buffer-name buf) +oreo/keep-buffers)))
        (buffers (buffer-list)))
    (mapcar #'kill-buffer (cl-remove-if should-not-kill buffers))))
#+end_src
** Custom window management
Emacs' default window management is horrendous, using other windows on
a whim as if your carefully crafted window setup doesn't exist!
Thankfully you can change this behaviour via the
~display-buffer-alist~ which matches regular expressions on buffer
names with a set of properties and functions that dictate how the
window for a buffer should be displayed.  It's a bit verbose but once
you get the hang of it it's actually really unique.

Here I add a use-package keyword to make ~display-buffer-alist~
records within a single use-package call instead of doing the
~add-to-list~ yourself.  I have no idea whether it's optimal AT ALL,
but it works for me.

2024-04-23: Found this option ~switch-to-buffer-obey-display-actions~
which makes manual buffer switches obey the same constraints via
~display-buffer-alist~ as creating the buffer automatically.
#+begin_src emacs-lisp
(use-package window
  :demand t
  :init
  (setq switch-to-buffer-obey-display-actions nil)
  (with-eval-after-load "use-package-core"
    (add-to-list 'use-package-keywords ':display)
    (defun use-package-normalize/:display (_name-symbol _keyword args)
      "Normalise args for use in handler.  Don't do anything to the args
here."
      args)

    (defun use-package-handler/:display (name _keyword args rest state)
      (use-package-concat
       (use-package-process-keywords name rest state)
       (mapcar
        #'(lambda (arg)
            `(add-to-list 'display-buffer-alist
                          ',arg))
        args)))))
#+end_src

Here's some ~:display~ records for buffers that don't really have
configuration anywhere else in the file.  Good examples as well on how
to use the keyword.
#+begin_src emacs-lisp
(use-package window
  :defer t
  :display
  ("\\*Process List\\*"
   (display-buffer-at-bottom)
   (window-height . 0.25))

  ("\\*Async Shell Command\\*"
   (display-buffer-at-bottom)
   (window-height . 0.25)))
#+end_src
** add-to-list multiple times
I want to be able to add multiple items to a list.  Here's a macro to
do that for me.

#+begin_src emacs-lisp
(defmacro add-multiple-to-list (listvar &rest elements)
  (cons
   'progn
   (cl-loop for element in elements
            collect `(cl-pushnew ,element ,listvar))))
#+end_src
* Aesthetics
General look and feel of Emacs (mostly disabling stuff I don't like).
** Themes
I have both a dark and light theme for differing situations.
*** Dark theme
My preferred dark theme is my own "personal-solarized" theme which is
stored in the Emacs lisp folder (look at
[[file:elisp/personal-solarized-theme.el][this file]]).  It's
essentially a copy of the solarized theme (from the ~solarized-themes~
package) with a few personal changes.
#+begin_src emacs-lisp
(use-package custom
  :init
  (setq custom-theme-directory (concat user-emacs-directory "elisp/"))
  :config
  (load-theme 'personal-solarized t))
#+end_src
*** Switching between light and dark
I'm not very good at designing light themes as I don't really use
them.  However they are necessary in high light situations where a
dark mode would strain the eyes too much.  So I built a custom theme
on top of the default Emacs theme, "personal-light".

2024-06-11: I now use modus-operandi for my light theme.

I don't use it by default but I may need to switch between light and
dark easily, so here's a command to switch between them.

#+begin_src emacs-lisp
(use-package custom
  :defer t
  :commands +oreo/switch-theme
  :init
  (defvar +oreo/theme 'dark)
  :config
  (defun +oreo/switch-theme ()
    (interactive)
    (cl-case +oreo/theme
      (dark
       (mapc #'disable-theme custom-enabled-themes)
       (load-theme 'modus-operandi t)
       (setq +oreo/theme 'light))
      (light
       (mapc #'disable-theme custom-enabled-themes)
       (load-theme 'personal-solarized t)
       (setq +oreo/theme 'dark)))))
#+end_src
** Font size
Make font size bigger on my laptop and smaller on my desktop.
#+begin_src emacs-lisp
(use-package faces
  :defer t
  :config
  (set-face-attribute 'default nil :height
                      (system-name-cond
                       ("newboy" 145)
                       ("oldboy" 135))))
#+end_src
** Startup screen
The default startup screen is quite bad in all honesty.  While for a
first time user it can be very helpful in running the tutorial and
finding out more about Emacs, for someone who's already configured it
there isn't much point.

The scratch buffer is an interaction buffer, made when Emacs is first
started, to quickly prototype Emacs Lisp code.  When startup screen is
disabled, this buffer is the first thing presented on boot for Emacs.
So we can use it to store some useful information.

2024-06-04: I use to load [[*Org mode][org-mode]] here for the scratch
buffer and it literally added 2 seconds of load time, so let's just
use fundamental mode and call it a day.
#+begin_src emacs-lisp
(use-package emacs
  :defer t
  :init
  (setq inhibit-startup-screen t
        inhibit-startup-echo-area-message user-login-name
        initial-major-mode 'fundamental-mode
        initial-scratch-message ""
        ring-bell-function 'ignore)
  :config
  (add-hook
   'emacs-startup-hook
   (proc
    (with-current-buffer "*scratch*"
      (goto-char (point-max))
      (insert
       (format
        "Emacs v%s - %s\n"
        emacs-version (emacs-init-time)))))))
#+end_src
** Blinking cursor
Configure the blinking cursor.
#+begin_src emacs-lisp
(use-package frame
  :defer t
  :init
  (setq blink-cursor-delay 0.2)
  :config
  (blink-cursor-mode))
#+end_src
** Mode line
The mode line is the little bar at the bottom of the buffer, just
above the minibuffer.  It can store quite literally anything, but
generally stuff like the buffer name, file type, column and line info,
etc is put there.

The default mode-line is... disgusting.  It displays information in an
unintelligible format and seems to smash together a bunch of
information without much care for ordering.  Most heartbreaking is
that *anything* can seemingly append new information without any
purview, which can be really annoying.  This means it can be very
overstimulating to look at, without even being that immediately
informative.

I've got a custom Emacs lisp package
([[file:elisp/better-mode-line.el][here]]) which sets up the default
mode line as a set of 3 segments: left, centre and right.  It pads out
the mode line with space strings to achieve this.
#+begin_src emacs-lisp
(use-package better-mode-line
  :load-path "elisp/"
  :demand t
  :init
  (defun +mode-line/evil-state ()
    "Returns either the empty string if no evil-state is defined or
the first character of the evil state capitalised"
    (with-eval-after-load "evil"
      (if (bound-and-true-p evil-state)
          (upcase
           (substring
            (format "%s"
                    evil-state)
            0 1))
        "")))

  (setq better-mode-line/left-segment
        '("    "
          (:eval
           (when (mode-line-window-selected-p)
             '("%l:%c"             ;; Line and column count
               "     "
               "%p"                ;; Percentage into buffer
               ("["                ;; Evil state
                (:eval
                 (+mode-line/evil-state))
                "]")
               ))))
        better-mode-line/centre-segment
        '("%+"                     ;; Buffer state (changed or not)
          "%b"                     ;; Buffer name
          ("("                     ;; Major mode
           (:eval (format "%s" major-mode))
           ")"))
        better-mode-line/right-segment
        '((:eval
           (when (mode-line-window-selected-p)
             (if (project-current) ;; Name of current project (if any)
                 (concat
                  (project-name (project-current))
                  " "
                  vc-mode          ;; Git branch
                  ))))
          mode-line-misc-info      ;; Any other information
          (:eval                   ;; Compilation mode errors
           (if (eq major-mode 'compilation-mode)
               compilation-mode-line-errors))
          "    "                   ;; Extra padding
          ))
  :config
  (better-mode-line/setup-mode-line))
#+end_src
** Fringes
Turning off borders in my window manager was a good idea, so turn off
the borders for Emacs, so called fringes.  However, some things like
[[info:emacs#Compilation Mode][Compilation Mode]] do require fringes
to provide arrows.  So I use the default-minimal fringe style (exactly
1 pixel on either side of the window) to ensure I get those.
#+begin_src emacs-lisp
(use-package fringe
  :defer t
  :config
  (set-fringe-style (cons 1 1)))
#+end_src
** Mouse
Who uses a mouse? This disables the use of GUI dialogues for stuff.
#+begin_src emacs-lisp
(setq-default use-file-dialog nil
              use-dialog-box nil)
#+end_src
** Scrolling
Emacs can automatically scroll the buffer depending on how many lines
the cursor is away from the limits of the window.  Here I set the
margin to 8 (so it'll start correcting at 8) and scroll-conservatively
to the same value so it'll keep the cursor centred.
#+begin_src emacs-lisp
(use-package emacs
  :init
  (setq scroll-conservatively 8
        scroll-margin 8))
#+end_src
* Core packages
For my core packages, whose configuration doesn't change much anyway,
** General
General provides a great solution for binding keys.  It has evil and
use-package support so it fits nicely into configuration.  In this
case, I define a "definer" for the "LEADER" keys.  Leader is bound to
~SPC~ and it's functionally equivalent to the doom/spacemacs leader.
Local leader is bound to ~SPC ,~ and it's similar to doom/spacemacs
leader but doesn't try to fully assimilate the local-leader map,
instead just picking stuff I think is useful.  This forces me to learn
only as many bindings as I find necessary; no more, no less.

I also define prefix leaders for differing applications.  These are
quite self explanatory by their name and provide a nice way to
visualise all bindings under a specific heading just by searching the
code.
#+begin_src emacs-lisp
(use-package general
  :straight t
  :demand t
  :config
  ;; General which key definitions for leaders
  (general-def
    :states '(normal motion)
    "SPC"   'nil
    "\\"    '(nil :which-key "Local leader")
    "SPC a" '(nil :which-key "Applications")
    "SPC b" '(nil :which-key "Buffers")
    "SPC c" '(nil :which-key "Code")
    "SPC d" '(nil :which-key "Directories")
    "SPC f" '(nil :which-key "Files")
    "SPC i" '(nil :which-key "Insert")
    "SPC m" '(nil :which-key "Modes")
    "SPC r" '(nil :which-key "Tabs")
    "SPC s" '(nil :which-key "Search")
    "SPC t" '(nil :which-key "Shell")
    "SPC q" '(nil :which-key "Quit/Literate"))

  (general-create-definer leader
    :states '(normal motion)
    :keymaps 'override
    :prefix "SPC")

  (general-create-definer local-leader
    :states '(normal motion)
    :prefix "\\")

  (general-create-definer code-leader
    :states '(normal motion)
    :keymaps 'override
    :prefix "SPC c")

  (general-create-definer file-leader
    :states '(normal motion)
    :keymaps 'override
    :prefix "SPC f")

  (general-create-definer shell-leader
    :states '(normal motion)
    :keymaps 'override
    :prefix "SPC t")

  (general-create-definer tab-leader
    :states '(normal motion)
    :keymaps 'override
    :prefix "SPC r")

  (general-create-definer mode-leader
    :states '(normal motion)
    :keymaps 'override
    :prefix "SPC m")

  (general-create-definer app-leader
    :states '(normal motion)
    :keymaps 'override
    :prefix "SPC a")

  (general-create-definer search-leader
    :states '(normal motion)
    :keymaps 'override
    :prefix "SPC s")

  (general-create-definer buffer-leader
    :states '(normal motion)
    :keymaps 'override
    :prefix "SPC b")

  (general-create-definer quit-leader
    :states '(normal motion)
    :keymaps 'override
    :prefix "SPC q")

  (general-create-definer insert-leader
    :states '(normal motion)
    :keymaps 'override
    :prefix "SPC i")

  (general-create-definer dir-leader
    :states '(normal motion)
    :keymaps 'override
    :prefix "SPC d")

  (general-create-definer general-nmmap
    :states '(normal motion))

  (defalias 'nmmap #'general-nmmap)

  (general-evil-setup t))
#+end_src
*** Some binds for Emacs
Some bindings that I couldn't fit elsewhere easily.
#+begin_src emacs-lisp
(use-package emacs
  :after general
  :general
  ("C-x d" #'delete-frame)

  (nmmap
    "M-;" #'eval-expression
    "g="  #'align-regexp
    "C--" #'text-scale-decrease
    "C-=" #'text-scale-increase
    "C-+" #'text-scale-adjust)

  (leader
    "SPC" '(execute-extended-command :which-key "M-x")
    "R"   `(revert-buffer :which-key "Revert buffer")
    "p"   `(,project-prefix-map :which-key "Project")
    "'"   '(browse-url-emacs :which-key "Download URL to Emacs")
    ":"   `(,(proc (interactive) (switch-to-buffer "*scratch*"))
            :which-key "Switch to *scratch*")
    "!"   '(async-shell-command :which-key "Async shell command")
    "h"   '(help-command :which-key "Help"))

  (mode-leader
    "T" #'+oreo/switch-theme)

  (code-leader
    "F" `(,(proc (interactive) (find-file "~/Code/"))
          :which-key "Open ~/Code/"))

  (file-leader
    "f" #'find-file
    "F" #'find-file-other-window
    "t" #'find-file-other-tab
    "s" #'save-buffer)

  (buffer-leader
    "b" #'switch-to-buffer
    "d" #'kill-current-buffer
    "c" #'kill-buffer-and-window
    "K" #'kill-buffer
    "j" #'next-buffer
    "k" #'previous-buffer
    "D" '(+oreo/clean-buffers :which-key "Kill most buffers"))

  (quit-leader
    "q" #'save-buffers-kill-terminal
    "c" #'+literate/compile-config
    "C" #'+literate/clean-config
    "l" #'+literate/load-config)

  (search-leader "i" #'imenu))
#+end_src
** Evil
My editor journey started off with Vim rather than Emacs, so my brain
has imprinted on its style.  Thankfully Emacs is super extensible so
there exists a package (more of a supreme system) for porting Vim's
modal editing style to Emacs, called Evil (Emacs Vi Layer).

However there are a lot of packages in Vim that provide greater
functionality, for example 'vim-surround'.  Emacs, by default, has
these capabilities but there are further packages which integrate them
into Evil.
*** Evil core
Setup the evil package, with some opinionated keybindings:
+ Switch ~evil-upcase~ and ~evil-downcase~ because I use ~evil-upcase~
  more
+ Switch ~evil-goto-mark~ and ~evil-goto-mark-line~ as I'd rather have
  the global one closer to the home row
+ Use 'T' character as an action for "transposing objects"
  + Swapping any two textual "objects" is such a Vim thing (the verb
    object model) but by default it can't seem to do it.  But Emacs
    can...
#+begin_src emacs-lisp
(use-package evil
  :straight t
  :demand t
  :general
  (leader
    "w"  '(evil-window-map :which-key "Window")
    "wT" #'window-swap-states
    "wd" #'evil-window-delete)

  (nmmap
    "K"   #'man
    "TAB" #'evil-jump-item
    "r"   #'evil-replace-state
    "zC"  #'hs-hide-level
    "zO"  #'hs-show-all
    "'"   #'evil-goto-mark
    "`"   #'evil-goto-mark-line)

  (general-def
    :keymaps 'override
    :states '(normal motion visual)
    "gu"  #'evil-upcase
    "gU"  #'evil-downcase
    "M-y" #'yank-pop
    "T"   nil)

  (general-def
    :keymaps 'override
    :states '(normal motion visual)
    :infix "T"
    "w" #'transpose-words
    "c" #'transpose-chars
    "s" #'transpose-sentences
    "p" #'transpose-paragraphs
    "e" #'transpose-sexps
    "l" #'transpose-lines)
  :init
  (setq evil-want-keybinding nil
        evil-split-window-below t
        evil-vsplit-window-right t
        evil-move-beyond-eol t
        evil-want-abbrev-expand-on-insert-exit t
        evil-undo-system #'undo-tree)
  :config
  (evil-mode))
#+end_src
*** Evil surround
Evil surround is a port for vim-surround.
#+begin_src emacs-lisp
(use-package evil-surround
  :after evil
  :straight t
  :config
  (global-evil-surround-mode))
#+end_src
*** Evil commentary
Allows generalised commenting of objects easily.
#+begin_src emacs-lisp
(use-package evil-commentary
  :after evil
  :straight t
  :config
  (evil-commentary-mode))
#+end_src
*** Evil multi cursor
Setup for multi cursors in Evil mode.  Don't let evil-mc setup it's own
keymap because it uses 'gr' as its prefix, which I don't like.
#+begin_src emacs-lisp
(use-package evil-mc
  :after evil
  :straight t
  :init
  (defvar evil-mc-key-map (make-sparse-keymap))
  :general
  (nmap
    :infix "gz"
    "q" #'evil-mc-undo-all-cursors
    "d" #'evil-mc-make-and-goto-next-match
    "j" #'evil-mc-make-cursor-move-next-line
    "k" #'evil-mc-make-cursor-move-prev-line
    "j" #'evil-mc-make-cursor-move-next-line
    "m" #'evil-mc-make-all-cursors
    "z" #'evil-mc-make-cursor-here
    "r" #'evil-mc-resume-cursors
    "s" #'evil-mc-pause-cursors
    "u" #'evil-mc-undo-last-added-cursor)
  :config
  (global-evil-mc-mode))
  ;; (evil-mc-define-vars)
  ;; (evil-mc-initialize-vars)
  ;; (add-hook 'evil-mc-before-cursors-created #'evil-mc-pause-incompatible-modes)
  ;; (add-hook 'evil-mc-before-cursors-created #'evil-mc-initialize-active-state)
  ;; (add-hook 'evil-mc-after-cursors-deleted  #'evil-mc-teardown-active-state)
  ;; (add-hook 'evil-mc-after-cursors-deleted  #'evil-mc-resume-incompatible-modes)
  ;; (advice-add #'evil-mc-initialize-hooks :override #'ignore)
  ;; (advice-add #'evil-mc-teardown-hooks :override #'evil-mc-initialize-vars)
  ;; (advice-add #'evil-mc-initialize-active-state :before #'turn-on-evil-mc-mode)
  ;; (advice-add #'evil-mc-teardown-active-state :after #'turn-off-evil-mc-mode)
  ;; (add-hook 'evil-insert-state-entry-hook #'evil-mc-resume-cursors)
#+end_src

*** Evil collection
Provides a community based set of keybindings for most modes in
Emacs.  I don't necessarily like all my modes having these bindings
though, as I may disagree with some.  So I use it in a mode to mode basis.
#+begin_src emacs-lisp
(use-package evil-collection
  :straight t
  :after evil)
#+end_src
*** Evil number
Increment/decrement a number at point like Vim does, but use bindings
that don't conflict with Emacs default.
#+begin_src emacs-lisp
(use-package evil-numbers
  :straight t
  :defer t
  :general
  (nmmap
    "+" #'evil-numbers/inc-at-pt
    "-" #'evil-numbers/dec-at-pt))
#+end_src
** Completion
Emacs is a text based interface.  Completion is its bread and butter
in providing good user experience.  By default Emacs provides
'completions-list' which produces a buffer of options which can be
searched and selected.  We can take this further though!

Ivy and Helm provide more modern interfaces, though Helm is quite
heavy.  Ivy, on the other hand, provides an interface similar to Ido
with less clutter and better customisation options.
*** Ivy
Setup for ivy, in preparation for counsel.  Turn on ivy-mode just
after init.

Setup vim-like bindings for the minibuffer ("M-(j|k)" for down|up the
selection list).
#+begin_src emacs-lisp
(use-package ivy
  :straight t
  :demand t
  :display
  ("\\*ivy-occur.*"
   (display-buffer-at-bottom)
   (window-height . 0.25))
  :general
  (general-def
    :keymaps 'ivy-minibuffer-map
    "C-j"    #'ivy-yank-symbol
    "M-j"    #'ivy-next-line-or-history
    "M-k"    #'ivy-previous-line-or-history
    "C-SPC"  #'ivy-occur)
  (general-def
    :keymaps  'ivy-switch-buffer-map
    "M-j"     #'ivy-next-line-or-history
    "M-k"     #'ivy-previous-line-or-history)
  (nmap
    :keymaps '(ivy-occur-mode-map ivy-occur-grep-mode-map)
    "RET"    #'ivy-occur-press-and-switch
    "J"      #'ivy-occur-press
    "gr"     #'ivy-occur-revert-buffer
    "q"      #'quit-window
    "D"      #'ivy-occur-delete-candidate
    "W"      #'ivy-wgrep-change-to-wgrep-mode
    "{"      #'compilation-previous-file
    "}"      #'compilation-next-file)
  :init
  (with-eval-after-load "evil"
    (evil-set-initial-state 'ivy-occur-mode 'normal)
    (evil-set-initial-state 'ivy-occur-grep-mode 'normal))
  (setq ivy-height 8
        ivy-height-alist nil
        ivy-wrap t
        ivy-fixed-height-minibuffer t
        ivy-use-virtual-buffers nil
        ivy-virtual-abbreviate 'full
        ivy-on-del-error-function #'ignore
        ivy-use-selectable-prompt t)
  :config
  (ivy-mode 1))
#+end_src
*** Counsel
Setup for counsel.  Load as late as possible, after ivy force requires
it.
#+begin_src emacs-lisp
(use-package counsel
  :straight t
  :after ivy
  :general
  (search-leader
    "s" #'counsel-grep-or-swiper
    "R" #'counsel-rg)
  (file-leader
    "r" #'counsel-recentf)
  (insert-leader
    "c" #'counsel-unicode-char)
  (general-def
    [remap describe-bindings]        #'counsel-descbinds
    [remap load-theme]               #'counsel-load-theme)
  :config
  (setq ivy-initial-inputs-alist '((org-insert-link . "^"))
        counsel-describe-function-function #'helpful-callable
        counsel-describe-variable-function #'helpful-variable
        counsel-grep-swiper-limit 1500000
        ivy-re-builders-alist '((swiper . ivy--regex-plus)
                                (counsel-grep-or-swiper . ivy--regex-plus)
                                (counsel-rg . ivy--regex-plus)
                                (t . ivy--regex-ignore-order)))
  (counsel-mode 1))
#+end_src
*** Amx
Amx is a fork of Smex that works to enhance the
execute-extended-command interface.  It also provides support for ido
or ivy (though I'm likely to use ido here) and allows you to switch
between them.

It provides a lot of niceties such as presenting the key bind when
looking for a command.

#+begin_src emacs-lisp
(use-package amx
  :straight t
  :defer 2
  :init
  (setq amx-backend 'auto)
  :config
  (amx-mode))
#+end_src
*** Orderless
Orderless sorting method for completion, probably one of the best
things ever.
#+begin_src emacs-lisp
(use-package orderless
  :straight t
  :after (ivy ido)
  :config
  (setq completion-styles '(orderless basic)
        completion-category-defaults nil
        completion-category-overrides '((file (styles partial-completion))))
  (setf (alist-get t ivy-re-builders-alist) 'orderless-ivy-re-builder))
#+end_src
*** Completions-list
In case I ever use the completions list, some basic commands to look
around.
#+begin_src emacs-lisp
(use-package simple
  :defer t
  :general
  (nmmap
    :keymaps 'completion-list-mode-map
    "l"   #'next-completion
    "h"   #'previous-completion
    "ESC" #'delete-completion-window
    "q"   #'quit-window
    "RET" #'choose-completion)
  :config
  (with-eval-after-load "evil"
    (evil-set-initial-state 'completions-list-mode 'normal)))
#+end_src
*** Company
Company is the auto complete system I use.  I don't like having heavy
setups for company as it only makes it slower to use.  In this case,
just setup some evil binds for company.
#+begin_src emacs-lisp
(use-package company
  :defer t
  :straight t
  :hook
  (prog-mode-hook   . company-mode)
  (eshell-mode-hook . company-mode)
  :general
  (imap
    "C-SPC" #'company-complete
    "C-@" #'company-complete
    "M-j" #'company-select-next
    "M-k" #'company-select-previous))
#+end_src
** Pretty symbols
Prettify symbols mode allows for users to declare 'symbols' that
replace text within certain modes.  Though this may seem like useless
eye candy, it has aided my comprehension and speed of recognition
(recognising symbols is easier than words).

Essentially a use-package keyword which makes declaring pretty symbols
for language modes incredibly easy.  Checkout my [[C/C++][C/C++]] configuration
for an example.
#+begin_src emacs-lisp
(use-package prog-mode
  :demand t
  :init
  (setq prettify-symbols-unprettify-at-point t)
  :config
  (with-eval-after-load "use-package-core"
    (add-to-list 'use-package-keywords ':pretty)
    (defun use-package-normalize/:pretty (_name-symbol _keyword args)
      args)

    (defun use-package-handler/:pretty (name _keyword args rest state)
      (use-package-concat
       (use-package-process-keywords name rest state)
       (mapcar
        #'(lambda (arg)
            (let ((mode (car arg))
                  (rest (cdr arg)))
              `(add-hook
                ',mode
                #'(lambda nil
                    (setq prettify-symbols-alist ',rest)
                    (prettify-symbols-mode)))))
        args)))))
#+end_src

Here's a collection of keywords and possible associated symbols for
any prog language of choice.  Mostly for reference and copying.
#+begin_example
("null"   . "Ø")
("list"   . "ℓ")
("string" . "𝕊")
("true"   . "⊤")
("false"  . "⊥")
("char"   . "ℂ")
("int"    . "ℤ")
("float"  . "ℝ")
("!"      . "¬")
("&&"     . "∧")
("||"      . "∨")
("for"    . "∀")
("return" . "⟼")
("print"  . "ℙ")
("lambda" . "λ")
#+end_example
** Tabs
Tabs in vscode are just like buffers in Emacs but way slower and
harder to use.  Tabs in Emacs are essentially window layouts, similar
to instances in Tmux.  With this setup I can use tabs quite
effectively.

#+begin_src emacs-lisp
(use-package tab-bar
  :defer t
  :init
  (setq tab-bar-show 1)
  :config
  (tab-bar-mode)
  :general
  (tab-leader
    "R" #'tab-rename
    "c" #'tab-close
    "d" #'tab-close
    "f" #'tab-detach
    "h" #'tab-move-to
    "j" #'tab-next
    "k" #'tab-previous
    "l" #'tab-move
    "n" #'tab-new
    "r" #'tab-switch
    "w" #'tab-window-detach)
  (mode-leader
    "t" #'toggle-tab-bar-mode-from-frame))
#+end_src
** Auto typing
Snippets are a pretty nice way of automatically inserting code.  Emacs
provides a ton of packages by default to do this, but there are great
packages to install as well.

Abbrevs and skeletons make up a popular solution within Emacs default.
Abbrevs are for simple expressions wherein the only input is the key,
and the output is some Elisp function.  They provide a lot of inbuilt
functionality and are quite useful.  Skeletons, on the other hand, are
for higher level insertions

The popular external solution is Yasnippet.  Yasnippet is a great
package for snippets, which I use heavily in programming and org-mode.
I setup here the global mode for yasnippet and a collection of
snippets for ease of use.
*** Abbrevs
Just define a few abbrevs for various date-time operations.  Also
define a macro that will assume a function for the expansion, helping
with abstracting a few things away.
#+begin_src emacs-lisp
(use-package abbrev
  :defer t
  :hook
  (prog-mode-hook . abbrev-mode)
  (text-mode-hook . abbrev-mode)
  :init
  (defmacro +abbrev/define-abbrevs (abbrev-table &rest abbrevs)
    `(progn
       ,@(mapcar #'(lambda (abbrev)
                `(define-abbrev
                   ,abbrev-table
                   ,(car abbrev)
                   ""
                   (proc (insert ,(cadr abbrev)))))
            abbrevs)))
  (setq save-abbrevs nil)
  :config
  (+abbrev/define-abbrevs
   global-abbrev-table
   ("sdate"
    (format-time-string "%Y-%m-%d" (current-time)))
   ("stime"
    (format-time-string "%H:%M:%S" (current-time)))
   ("sday"
    (format-time-string "%A" (current-time)))
   ("smon"
    (format-time-string "%B" (current-time)))))
#+end_src
*** Auto insert
Allows inserting text immediately upon creating a new buffer with a
given name.  Supports skeletons for inserting text.  To make it easier
for later systems to define their own auto inserts, I define a
~use-package~ keyword ~auto-insert~ which allows one to define an
entry for ~auto-insert-alist~.
#+begin_src emacs-lisp
(use-package autoinsert
  :demand t
  :hook (emacs-startup-hook . auto-insert-mode)
  :config
  (with-eval-after-load "use-package-core"
    (add-to-list 'use-package-keywords ':auto-insert)
    (defun use-package-normalize/:auto-insert (_name-symbol _keyword args)
      args)
    (defun use-package-handler/:auto-insert (name _keyword args rest state)
      (use-package-concat
       (use-package-process-keywords name rest state)
       (mapcar
        #'(lambda (arg)
            `(add-to-list
              'auto-insert-alist
              ',arg))
        args)))))
#+end_src
*** Yasnippet
Look at the snippets [[file:../.config/yasnippet/snippets/][folder]]
for all snippets I've got.
#+begin_src emacs-lisp
(use-package yasnippet
  :straight t
  :defer t
  :hook
  (prog-mode-hook . yas-minor-mode)
  (text-mode-hook . yas-minor-mode)
  :general
  (insert-leader
    "i" #'yas-insert-snippet)
  :config
  (yas-load-directory (no-littering-expand-etc-file-name "yasnippet/snippets")))
#+end_src
*** Hydra
Hydra is a great package by =abo-abo= (yes the same guy who made ivy
and swiper) and I hope to use it later on in the config.  There are
two use-package declarations here: one for ~hydra~ itself, and the
other for ~use-package-hydra~ which provides the keyword ~:hydra~ in
use-package declarations.
#+begin_src emacs-lisp
(use-package hydra
  :straight t)

(use-package use-package-hydra
  :straight t)

(use-package hydra
  :hydra
  (hydra-window-resize
   nil "Resize the current window effectively"
   ("l" #'evil-window-increase-width)
   ("h" #'evil-window-decrease-width)
   ("j" #'evil-window-decrease-height)
   ("k" #'evil-window-increase-height)
   ("=" #'balance-windows))
  :general
  (leader
    "wr" #'hydra-window-resize/body))
#+end_src
* Small packages
** Info
Info is GNU's attempt at better man pages.  Most Emacs packages have
info pages so I'd like nice navigation options.
#+begin_src emacs-lisp
(use-package info
  :defer t
  :general
  (nmmap
    :keymaps 'Info-mode-map
    "h" #'evil-backward-char
    "k" #'evil-previous-line
    "l" #'evil-forward-char
    "H" #'Info-history-back
    "L" #'Info-history-forward
    "RET" #'Info-follow-nearest-node))
#+end_src
** Display line numbers
I don't really like line numbers, I find them similar to
[[*Fringes][fringes]] (useless space), but at least it provides some
information.  Sometimes it can help with doing repeated commands so a
toggle option is necessary.
#+begin_src emacs-lisp
(use-package display-line-numbers
  :defer t
  :commands display-line-numbers-mode
  :general
  (mode-leader
    "l" #'display-line-numbers-mode)
  :init
  (setq-default display-line-numbers-type 'relative))
#+end_src
** WAIT esup
:PROPERTIES:
:header-args:emacs-lisp: :tangle no
:END:
I used to be able to just use
[[file:elisp/profiler-dotemacs.el][profile-dotemacs.el]], when my
Emacs config was smaller, but now it tells me very little information
about where my setup is inefficient due to the literate config.  Just
found this ~esup~ thing and it works perfectly, exactly how I would
prefer getting this kind of information.  It runs an external Emacs
instance and collects information from it, so it doesn't require
restarting Emacs to profile, and I can compile my configuration in my
current instance to test it immediately.

2023-10-16: Unless I'm doing some optimisations or tests, I don't
really need this in my config at all times.  Enable when needed.
#+begin_src emacs-lisp
(use-package esup
  :straight t
  :defer t)
#+end_src
** Hl-line
:PROPERTIES:
:header-args:emacs-lisp: :tangle no
:END:
Highlights the current line.
#+begin_src emacs-lisp
(use-package hl-line
  :straight t
  :defer t
  :hook (text-mode-hook . hl-line-mode)
  :hook (prog-mode-hook . hl-line-mode))
#+end_src
** Recentf
Recentf provides a method of keeping track of recently opened files.
#+begin_src emacs-lisp
(use-package recentf
  :defer t
  :hook (emacs-startup-hook . recentf-mode))
#+end_src
** Avy
Setup avy with leader.  As I use ~avy-goto-char-timer~ a lot, use the
~C-s~ bind which replaces isearch.  Switch isearch to M-s in case I
need to use it.
#+begin_src emacs-lisp
(use-package avy
  :straight t
  :defer t
  :general
  (nmmap
    :keymaps 'override
    "C-s" #'avy-goto-char-timer
    "M-s" #'isearch-forward
    "gp"  #'avy-copy-region
    "gP"  #'avy-move-region
    "gl"  #'avy-goto-line
    "gw"  #'avy-goto-word-1))
#+end_src
** Ace window
Though evil provides a great many features in terms of window
management, ace window can provide some nicer chords for higher
management of windows (closing, switching, etc).

#+begin_src emacs-lisp
(use-package ace-window
  :straight t
  :defer t
  :custom
  (aw-keys '(?a ?s ?d ?f ?g ?h ?j ?k ?l))
  :general
  (nmmap
    [remap evil-window-next] #'ace-window))
#+end_src
** Ace link
Avy-style link following!
#+begin_src emacs-lisp
(use-package ace-link
  :straight t
  :defer t
  :general
  (nmmap
    :keymaps 'override
    "gL" #'ace-link))
#+end_src
** Helpful
Helpful provides a modernised interface for some common help
commands.  I replace ~describe-function~, ~describe-variable~ and
~describe-key~ by their helpful counterparts.
#+begin_src emacs-lisp
(use-package helpful
  :straight t
  :defer t
  :commands (helpful-callable helpful-variable)
  :general
  (general-def
    [remap describe-function] #'helpful-callable
    [remap describe-variable] #'helpful-variable
    [remap describe-key]      #'helpful-key)
  :display
  ("\\*helpful.*"
   (display-buffer-at-bottom)
   (inhibit-duplicate-buffer . t)
   (window-height . 0.25))
  :config
  (evil-define-key 'normal helpful-mode-map "q" #'quit-window))
#+end_src
** Which-key
Which key uses the minibuffer when performing a keybind to provide
possible options for the next key.
#+begin_src emacs-lisp
(use-package which-key
  :straight t
  :after general
  :config
  (which-key-mode))
#+end_src
** (Rip)grep
Grep is a great piece of software, a necessary tool in any Linux
user's inventory.  By default Emacs has a family of functions to use
grep, presenting results in a ~compilation~ style.  ~grep~ searches
files, ~rgrep~ searches in a directory using the ~find~ program and
~zgrep~ searches archives.  This is a great solution for a general
computer environment; essentially all Linux installs will have ~grep~
and ~find~ installed.

Ripgrep is a Rust program that attempts to perform better than grep,
and it actually does.  This is because of a set of optimisations, such
as checking the =.gitignore= to exclude certain files from being
searched.  The ripgrep package provides utilities to ripgrep projects
and files for strings.  Though [[*Ivy][ivy]] comes with
~counsel-rg~, it uses Ivy's completion framework rather than the
~compilation~ style buffers, which sometimes proves very useful.

Of course, this requires installing the rg binary which is available
in most repositories nowadays.
*** Grep
I have no use for standard 'grep'; ~counsel-swiper~ does the same
thing faster and within Emacs lisp.  ~rgrep~ is useful though.
#+begin_src emacs-lisp
(use-package grep
  :defer t
  :display
  ("^\\*grep.*"
   (display-buffer-reuse-window display-buffer-at-bottom)
   (window-height . 0.35)
   (reusable-frames . t))
  :general
  (search-leader
    "d" #'rgrep)
  (nmmap
    :keymaps 'grep-mode-map
    "0" #'evil-beginning-of-line
    "q" #'quit-window
    "i" #'wgrep-change-to-wgrep-mode
    "c" #'recompile)
  (nmmap
    :keymaps 'wgrep-mode-map
    "q"  #'evil-record-macro
    "ZZ" #'wgrep-finish-edit
    "ZQ" #'wgrep-abort-changes)
  :config
  ;; Without this wgrep doesn't work properly
  (evil-set-initial-state 'grep-mode 'normal))
#+end_src
*** rg
#+begin_src emacs-lisp
(use-package rg
  :straight t
  :defer t
  :display
  ("^\\*\\*ripgrep\\*\\*"
   (display-buffer-reuse-window display-buffer-at-bottom)
   (window-height . 0.35)
   (reusable-frames . t))
  :general
  (search-leader
    "r" #'rg)
  (nmmap
    :keymaps 'rg-mode-map
    "c"  #'rg-recompile
    "C"  #'rg-rerun-toggle-case
    "]]" #'rg-next-file
    "[[" #'rg-prev-file
    "q"  #'quit-window
    "i"  #'wgrep-change-to-wgrep-mode)
  :init
  (setq rg-group-result t
        rg-hide-command t
        rg-show-columns nil
        rg-show-header t
        rg-custom-type-aliases nil
        rg-default-alias-fallback "all"
        rg-buffer-name "*ripgrep*")
  :config
  (evil-set-initial-state 'rg-mode 'normal))
#+end_src
** Olivetti
Olivetti provides a focus mode for Emacs, which makes it look a bit
nicer.  It uses margins by default and centres using fill-column.  I
actually really like olivetti mode particularly with my [[*Mode
line][centred mode-line]], so I also define a global minor mode which
enables it in all but the minibuffer.
#+begin_src emacs-lisp
(use-package olivetti
  :straight t
  :defer t
  :general
  (mode-leader
    "o" #'olivetti-global-mode)
  :init
  (setq-default olivetti-body-width nil)
  (setq-default olivetti-minimum-body-width 100)
  (setq olivetti-style nil)
  :config
  (define-globalized-minor-mode olivetti-global-mode olivetti-mode
    (lambda nil (unless (minibufferp)
           (olivetti-mode 1)))))
#+end_src
** All the Icons
Nice set of icons with a great user interface to manage them.
#+begin_src emacs-lisp
(use-package all-the-icons
  :straight t
  :defer t
  :commands (all-the-icons-insert)
  :general
  (insert-leader
    "e" #'all-the-icons-insert))
#+end_src
** Hide mode line
Custom minor mode to toggle the mode line.  Check it out at
[[file:elisp/hide-mode-line.el][elisp/hide-mode-line.el]].
#+begin_src emacs-lisp
(use-package hide-mode-line
  :load-path "elisp/"
  :defer t
  :general
  (mode-leader
    "m" #'hide-mode-line-mode))
#+end_src
** Save place
Saves current place in a buffer permanently, so on revisiting the file
(even in a different Emacs instance) you go back to the place you were
at last.
#+begin_src emacs-lisp
(use-package saveplace
  :defer t
  :config
  (save-place-mode))
#+end_src
** Licensing
Loads [[file:elisp/license.el][license.el]] for inserting licenses.
Licenses are important for distribution and attribution to be defined
clearly.
#+begin_src emacs-lisp
(use-package license
  :demand t
  :load-path "elisp/"
  :general
  (insert-leader
    "l" #'+license/insert-copyright-notice
    "L" #'+license/insert-complete-license))
#+end_src
** Memory-report
New feature of Emacs-29, gives a rough report of memory usage with
some details.  Useful to know on a long Emacs instance what could be
eating up memory.
#+begin_src emacs-lisp
(use-package memory-report
  :defer t
  :general
  (leader
    "qm" #'memory-report))
#+end_src
** Save minibuffer history
#+begin_src emacs-lisp
(use-package savehist
  :defer t
  :config
  (savehist-mode t))
#+end_src
** Drag Stuff
#+begin_src emacs-lisp
(use-package drag-stuff
  :straight t
  :defer t
  :general
  (nmmap
    "C-M-h" #'drag-stuff-left
    "C-M-j" #'drag-stuff-down
    "C-M-k" #'drag-stuff-up
    "C-M-l" #'drag-stuff-right))
#+end_src
** Searching git directories efficiently
Using [[file:elisp/search.el][search.el]] I can search a set of
directories particularly efficiently.
#+begin_src emacs-lisp
(use-package search
  :defer t
  :load-path "elisp/"
  :general
  (file-leader
    "p" #'+search/find-file
    "S" #'+search/search-all))
#+end_src
** Separedit
Edit anything anywhere all at once!
#+begin_src emacs-lisp
(use-package separedit
  :defer t
  :straight t
  :general
  (leader "e" #'separedit)
  :init
  (setq separedit-default-mode 'org-mode
        separedit-remove-trailing-spaces-in-comment t))
#+end_src
** lorem ipsum
Sometimes you need placeholder text for some UI or document.  Pretty
easy to guess what text I'd use.
#+begin_src emacs-lisp
(use-package lorem-ipsum
  :straight t
  :general
  (insert-leader
    "p" #'lorem-ipsum-insert-paragraphs))
#+end_src
** diff mode
Oh diffs; the way of the ancient ones.  Nowadays we use our newfangled
"pull requests" and "cool web interfaces" to handle change management
in our code repositories, but the old school projects use patches to
make code changes.  I actually somewhat like patches, if only for
their simplicity in concept.

[[https://git.aryadevchavali.com/dwm][dwm]] uses patches for adding
new features and Emacs has great functionality to work with patches
effectively.  Here I configure ~diff-mode~, which provides most of this
cool stuff, to be a bit more ergonomic with ~evil~.
#+begin_src emacs-lisp
(use-package diff-mode
  :general
  (nmmap
    :keymaps 'diff-mode-map
    "}" #'diff-hunk-next
    "{" #'diff-hunk-prev
    "RET" #'diff-goto-source))
#+end_src
* Applications
Emacs is basically an operating system whose primary datatype is text.
Applications are interfaces/environments which serve a variety of
purposes, but provide a lot of capability.
** EWW
Emacs Web Wowser is the inbuilt text based web browser for Emacs.  It
can render images and basic CSS styles but doesn't have a JavaScript
engine, which makes sense as it's primarily a text interface.
#+begin_src emacs-lisp
(use-package eww
  :defer t
  :general
  (app-leader
    "w" #'eww)
  (nmmap
    :keymaps 'eww-mode-map
    "w" #'evil-forward-word-begin
    "Y" #'eww-copy-page-url)
  :config
  (with-eval-after-load "evil-collection"
    (evil-collection-eww-setup)))
#+end_src
** Calendar
Calendar is a simple inbuilt application that helps with date
functionalities.  I add functionality to copy dates from the calendar
to the kill ring and bind it to "Y".
#+begin_src emacs-lisp
(use-package calendar
  :defer t
  :commands (+calendar/copy-date +calendar/toggle-calendar)
  :display
  ("\\*Calendar\\*"
   (display-buffer-at-bottom)
   (inhibit-duplicate-buffer . t)
   (window-height . 0.17))
  :general
  (nmmap
    :keymaps 'calendar-mode-map
    "Y" #'+calendar/copy-date)
  (app-leader
    "d" #'calendar)
  :config
  (defun +calendar/copy-date ()
    "Copy date under cursor into kill ring."
    (interactive)
    (if (use-region-p)
        (call-interactively #'kill-ring-save)
      (let ((date (calendar-cursor-to-date)))
        (when date
          (setq date (encode-time 0 0 0 (nth 1 date) (nth 0 date) (nth 2 date)))
          (kill-new (format-time-string "%Y-%m-%d" date)))))))
#+end_src
** Mail
Mail is a funny thing; most people use it just for business or
advertising and it's come out of use in terms of personal
communication in the west for the most part (largely due to "social"
media applications).  However, this isn't true for the open source and
free software movement who heavily use mail for communication.

Integrating mail into Emacs helps as I can send source code and
integrate it into my workflow just a bit better.
*** Notmuch
#+begin_src emacs-lisp
(use-package notmuch
  :straight t
  :defer t
  :commands (notmuch +mail/flag-thread)
  :general
  (app-leader "m" #'notmuch)
  (nmap
    :keymaps 'notmuch-search-mode-map
    "f" #'+mail/flag-thread)
  :init
  (defconst +mail/local-dir (no-littering-expand-var-file-name "mail/"))
  (setq notmuch-show-logo nil
        notmuch-search-oldest-first nil
        notmuch-hello-sections '(notmuch-hello-insert-saved-searches
                                 notmuch-hello-insert-alltags
                                 notmuch-hello-insert-recent-searches)
        notmuch-archive-tags '("-inbox" "-unread" "+archive")
        message-auto-save-directory +mail/local-dir
        message-directory +mail/local-dir)
  :config
  (defun +mail/flag-thread (&optional unflag beg end)
    (interactive (cons current-prefix-arg (notmuch-interactive-region)))
    (notmuch-search-tag
     (notmuch-tag-change-list '("-inbox" "+flagged") unflag) beg end)
    (when (eq beg end)
      (notmuch-search-next-thread)))
  (with-eval-after-load "evil-collection"
    (evil-collection-notmuch-setup)))
#+end_src
*** Smtpmail
#+begin_src emacs-lisp
(use-package smtpmail
  :defer t
  :commands mail-send
  :init
  (setq-default
   smtpmail-smtp-server "mail.aryadevchavali.com"
   smtpmail-smtp-user "aryadev"
   smtpmail-smtp-service 587
   smtpmail-stream-type 'starttls
   send-mail-function #'smtpmail-send-it
   message-send-mail-function #'smtpmail-send-it))
#+end_src
*** Mail signature using fortune
#+begin_src emacs-lisp
(use-package fortune
  :init
  (setq fortune-dir "/usr/share/fortune"
        fortune-file "/usr/share/fortune/cookie")
  :config
  (defvar +mail/signature "---------------\nAryadev Chavali\n---------------\n%s")
  (defun +mail/make-signature ()
    (interactive)
    (format +mail/signature
            (with-temp-buffer
              (let ((fortune-buffer-name (current-buffer)))
                (fortune-in-buffer t)
                (if (bolp) (delete-char -1))
                (buffer-string)))))
  (add-hook 'message-setup-hook
            (lambda nil (setq message-signature (+mail/make-signature)))))
#+end_src
** Dired
Dired: Directory editor for Emacs.  An incredibly nifty piece of
software which deeply integrates with Emacs as a whole.  Probably the
best file manager overall and for large scale file system tasks I
can't think of a better tool than this.

Here I setup dired with a few niceties
+ Hide details by default (no extra stuff from ~ls~)
+ Omit dot files by default (using ~dired-omit-mode~)
+ If I have two dired windows open, moving or copying files in one
  dired instance will automatically target the other dired window
  (~dired-dwim~)
+ If opening an application on a PDF file, suggest ~zathura~
+ Examine all the subdirectories within the same buffer
  (~+dired/insert-all-subdirectories~)
#+begin_src emacs-lisp
(use-package dired
  :defer t
  :commands (dired find-dired)
  :hook
  (dired-mode-hook . auto-revert-mode)
  (dired-mode-hook . dired-hide-details-mode)
  (dired-mode-hook . dired-omit-mode)
  :init
  (setq-default dired-listing-switches "-AFBlu --group-directories-first"
                dired-omit-files "^\\." ; dotfiles
                dired-omit-verbose nil
                dired-dwim-target t
                dired-kill-when-opening-new-dired-buffer t)
  (with-eval-after-load "evil-collection"
    (evil-collection-dired-setup))
  :general
  (nmmap
    :keymaps 'dired-mode-map
    "SPC"   nil
    "SPC ," nil
    "("     #'dired-hide-details-mode
    ")"     #'dired-omit-mode
    "T"     #'dired-create-empty-file
    "H"     #'dired-up-directory
    "L"     #'dired-find-file)
  (dir-leader
    "f" #'find-dired
    "d" #'dired
    "D" #'dired-other-window
    "i" #'image-dired
    "p" `(,(proc (interactive)
                 (dired "~/Text/PDFs/"))
          :which-key "Open PDFs"))
  (local-leader
    :keymaps 'dired-mode-map
    "i" #'dired-maybe-insert-subdir
    "I" #'+dired/insert-all-subdirectories
    "o" #'dired-omit-mode
    "k" #'dired-prev-subdir
    "j" #'dired-next-subdir
    "K" #'dired-kill-subdir
    "m" #'dired-mark-files-regexp
    "u" #'dired-undo)
  :config
  (add-to-list 'dired-guess-shell-alist-user '("\\.pdf\\'" "zathura"))
  (defun +dired/insert-all-subdirectories ()
    "Insert all subdirectories currently viewable."
    (interactive)
    (dired-mark-directories nil)
    (mapc #'dired-insert-subdir (dired-get-marked-files))
    (dired-unmark-all-marks)))
#+end_src
*** image-dired
Image dired is a little cherry on top for Dired: the ability to look
through swathes of images in a centralised fashion while still being
able to do all the usual dired stuff as well is really cool.
#+begin_src emacs-lisp
(use-package dired
  :defer t
  :init
  (setq image-dired-external-viewer "nsxiv")
  :general
  (nmmap
    :keymaps 'image-dired-thumbnail-mode-map
    "h"   #'image-dired-backward-image
    "l"   #'image-dired-forward-image
    "j"   #'image-dired-next-line
    "k"   #'image-dired-previous-line
    "H"   #'image-dired-display-previous
    "L"   #'image-dired-display-next
    "RET" #'image-dired-display-this
    "m"   #'image-dired-mark-thumb-original-file
    "q"   #'quit-window))
#+end_src
*** fd-dired
Uses fd for finding file results in a directory: ~find-dired~ ->
~fd-dired~.

#+begin_src emacs-lisp
(use-package fd-dired
  :straight t
  :after dired
  :general
  (dir-leader
    "g" #'fd-dired))
#+end_src
*** wdired
Similar to [[*(Rip)grep][wgrep]] =wdired= provides
the ability to use Emacs motions and editing on file names.  This
makes stuff like mass renaming and other file management tasks way
easier than even using the mark based system.
#+begin_src emacs-lisp
(use-package wdired
  :straight t
  :after dired
  :general
  (nmmap
    :keymaps 'dired-mode-map
    "W" #'wdired-change-to-wdired-mode)
  (nmmap
    :keymaps 'wdired-mode-map
    "ZZ" #'wdired-finish-edit
    "ZQ" #'wdired-abort-changes))
#+end_src
** Eshell
*** Why Eshell?
Eshell is an integrated shell environment for Emacs, written in Emacs
Lisp.  I argue henceforth that it is the best shell/command
interpreter to use in Emacs.

Eshell is unlike the other alternatives in Emacs as it's a /shell/
first, not a terminal emulator, with the ability to spoof some aspects
of a terminal emulator (through the shell parser).

The killer benefits of eshell (which would appeal particularly to an
Emacs user) are a direct result of eshell being written in Emacs Lisp:
- incredible integration with Emacs utilities (such as ~dired~,
  ~find-file~, any read functions, etc)
- very extensible, easy to write new commands which leverage Emacs
  commands as well as external utilities
- agnostic of platform: "eshell/cd" will call the underlying change
  directory function for you, so commands will (usually) mean the same
  thing regardless of platform
  - this means as long as Emacs can run on an operating system, one
    may run eshell

However, my favourite feature of eshell is the set of evaluators that
run on command input.  Some of the benefits listed above come as a
result of this powerful feature. These evaluators are described below.

Lisp evaluator: works on braced expressions, evaluating them as Lisp
expressions (e.g. ~(message "Hello, World!\n")~).  Any returned
objects are printed.  This makes eshell a LISP REPL!

External evaluator: works within curly braces, evaluating them via
some external shell process (like sh) (e.g. ~{echo "Hello,
world!\n"}~).  This makes eshell a (kinda dumb) terminal emulator!

The alias evaluator is the top level evaluator.  It is the main
evaluator for each expression given to eshell.  When given an
expression it tries to evaluate it by testing against these conditions:
- it's an alias defined by the user or in the ~eshell/~ namespace of
  functions (simplest evaluator)
- it's some form of lisp expression (lisp evaluator)
- it's an external command (bash evaluator)
Essentially, you get the best of both Emacs and external shell
programs *ALL WITHIN* Emacs for free.
*** Eshell keymaps, display and variables
Bind some evil-like movements for easy shell usage, a display record
so when you call eshell it kinda looks like VSCode's terminal popup.

NOTE: This mode doesn't allow you to set maps the normal way; you need
to set keybindings on eshell-mode-hook, otherwise it'll just overwrite
them.
#+begin_src emacs-lisp
(use-package eshell
  :defer t
  :display
  ("\\*.*eshell\\*"
   (display-buffer-same-window)
   (reusable-frames . t))
  :init
  (setq eshell-cmpl-ignore-case t
        eshell-cd-on-directory t
        eshell-highlight-prompt nil)
  (add-hook
   'eshell-mode-hook
   (proc
    (interactive)
    (nmap
      :keymaps 'eshell-mode-map
      "0" #'eshell-bol)
    (general-def
      :states '(normal insert)
      :keymaps 'eshell-mode-map
      "C-j" #'eshell-next-matching-input-from-input
      "C-k" #'eshell-previous-matching-input-from-input)
    (local-leader
      :keymaps 'eshell-mode-map
      "c" (proc (interactive) (eshell/clear)
                (recenter))
      "k" #'eshell-kill-process))))
#+end_src
*** Eshell prompt
Here I use my external library
[[file:elisp/eshell-prompt.el][eshell-prompt]], which provides a more
dynamic prompt for Eshell.  Current features include:
+ Git (with difference from remote and number of modified files)
+ Current date and time
+ A coloured prompt which changes colour based on the exit status of
  the previous command

NOTE: I don't defer this package because it doesn't use any eshell
internals, just standard old Emacs packages.
#+begin_src emacs-lisp
(use-package eshell-prompt
  :load-path "elisp/"
  :config
  (defun +eshell/banner-message ()
    (concat (shell-command-to-string "cowfortune") "\n"))
  (setq eshell-prompt-regexp (format "^%s" +eshell-prompt/user-prompt)
        eshell-prompt-function #'+eshell-prompt/make-prompt
        eshell-banner-message '(+eshell/banner-message)))
#+end_src
*** Eshell additions
Using my external library
[[file:elisp/eshell-additions.el][eshell-additions]], I get a few new
eshell internal commands and a surface command to open eshell at the
current working directory.

NOTE: I don't defer this package because it autoloads any eshell
internals that it uses so I'm only loading what I need to.  Any
~eshell/*~ functions need to be known by eshell before launching, so
if I loaded this ~:after~ eshell then the first instance has no
knowledge of the new additions.
#+begin_src emacs-lisp
(use-package eshell-additions
  :defer t
  :load-path "elisp/"
  :general
  (shell-leader
    "t" #'+eshell/open)
  (leader
    "T" #'+eshell/at-cwd))
#+end_src
*** Eshell syntax highlighting
This package external package adds syntax highlighting to eshell
(disabling it for remote work).  Doesn't require a lot of config
thankfully.
#+begin_src emacs-lisp
(use-package eshell-syntax-highlighting
  :straight t
  :after eshell
  :hook (eshell-mode-hook . eshell-syntax-highlighting-mode))
#+end_src
** WAIT Elfeed
:PROPERTIES:
:header-args:emacs-lisp: :tangle no
:END:
Elfeed is the perfect RSS feed reader, integrated into Emacs
perfectly.  I've got a set of feeds that I use for a large variety of
stuff, mostly media and entertainment.  I've also bound "<leader> ar"
to elfeed for loading the system.
#+begin_src emacs-lisp
(use-package elfeed
  :straight t
  :general
  (app-leader "r" #'elfeed)
  (nmmap
    :keymaps 'elfeed-search-mode-map
    "gr"       #'elfeed-update
    "s"        #'elfeed-search-live-filter
    "<return>" #'elfeed-search-show-entry)
  :init
  (setq elfeed-db-directory (no-littering-expand-var-file-name "elfeed/"))

  (setq +rss/feed-urls
        '(("Arch Linux"
           "https://www.archlinux.org/feeds/news/"
           News Technology)
          ("The Onion"
           "https://www.theonion.com/rss"
           Social)
          ("Protesilaos Stavrou"
           "https://www.youtube.com/@protesilaos"
           YouTube Technology)
          ("Tsoding Daily"
           "https://www.youtube.com/feeds/videos.xml?channel_id=UCrqM0Ym_NbK1fqeQG2VIohg"
           YouTube Technology)
          ("Tsoding"
           "https://www.youtube.com/feeds/videos.xml?channel_id=UCrqM0Ym_NbK1fqeQG2VIohg"
           YouTube Technology)
          ("Nexpo"
           "https://www.youtube.com/feeds/videos.xml?channel_id=UCpFFItkfZz1qz5PpHpqzYBw"
           YouTube Stories)
          ("3B1B"
           "https://www.youtube.com/feeds/videos.xml?channel_id=UCYO_jab_esuFRV4b17AJtAw"
           YouTube)
          ("Fredrik Knusden"
           "https://www.youtube.com/feeds/videos.xml?channel_id=UCbWcXB0PoqOsAvAdfzWMf0w"
           YouTube Stories)
          ("Barely Sociable"
           "https://www.youtube.com/feeds/videos.xml?channel_id=UC9PIn6-XuRKZ5HmYeu46AIw"
           YouTube Stories)
          ("Atrocity Guide"
           "https://www.youtube.com/feeds/videos.xml?channel_id=UCn8OYopT9e8tng-CGEWzfmw"
           YouTube Stories)
          ("Hacker News"
           "https://news.ycombinator.com/rss"
           Social News Technology)
          ("Hacker Factor"
           "https://www.hackerfactor.com/blog/index.php?/feeds/index.rss2"
           Social)))
  :config
  (with-eval-after-load "evil-collection"
    (evil-collection-elfeed-setup))

  (setq elfeed-feeds (cl-map 'list #'(lambda (item)
                                       (append (list (nth 1 item)) (cdr (cdr item))))
                             +rss/feed-urls))

  (advice-add  'elfeed-search-show-entry :after #'+elfeed/dispatch-entry)

  (defun +elfeed/dispatch-entry (entry)
    "Process each type of entry differently.
  e.g., you may want to open HN entries in eww."
    (let ((url (elfeed-entry-link entry)))
      (pcase url
        ((pred (string-match-p "https\\:\\/\\/www.youtube.com\\/watch"))
         (mpv-play-url url))
        (_ (eww url))))))
#+end_src
** Magit
Magit is *the* git porcelain for Emacs, which perfectly encapsulates
the git CLI.  It's so good that some people use Emacs just to use it.
It's difficult to describe well without using it, in my opinion, and
it integrates so well with Emacs that there is very little need to use
the git CLI ever.

In this case I just need to setup the bindings for it.  As magit will
definitely load after evil (as it must be run by a binding, and evil
will load after init), I can use evil-collection freely.  Also, define
an auto insert for commit messages so that I don't need to write
everything myself.

#+begin_src emacs-lisp
(use-package magit
  :straight t
  :defer t
  :display
  ("magit:.*"
   (display-buffer-same-window)
   (inhibit-duplicate-buffer . t))
  ("magit-diff:.*"
   (display-buffer-below-selected))
  ("magit-log:.*"
   (display-buffer-same-window))
  :general
  (leader
    "g" '(magit-dispatch :which-key "Magit"))
  (code-leader
    "b" #'magit-blame)
  :auto-insert
  (("COMMIT_EDITMSG" . "Commit skeleton")
   ""
   "(" (read-string "Enter feature/module: ") ")"
   (read-string "Enter simple description: ") "\n\n")
  :init
  (setq vc-follow-symlinks t
        magit-blame-echo-style 'lines
        magit-copy-revision-abbreviated t)
  :config
  (with-eval-after-load "evil"
    (evil-set-initial-state 'magit-status-mode 'motion))
  (with-eval-after-load "evil-collection"
    (evil-collection-magit-setup)))
#+end_src
** IBuffer
IBuffer is the dired of buffers: providing the ability to mark
buffers, mass rename/delete and just observe stuff.
#+begin_src emacs-lisp
(use-package ibuffer
  :defer t
  :general
  (buffer-leader
    "i" #'ibuffer)
  :config
  (with-eval-after-load "evil-collection"
    (evil-collection-ibuffer-setup)))
#+end_src
** Proced
Emacs has two systems for process management:
+ proced: a general 'top' like interface which allows general
  management of linux processes
+ list-processes: a specific Emacs based system that lists processes
  spawned by Emacs (similar to a top for Emacs specifically)

Core proced config, just a few bindings and evil collection setup.
#+begin_src emacs-lisp
(use-package proced
  :defer t
  :general
  (app-leader
    "p" #'proced)
  (nmap
    :keymaps 'proced-mode-map
    "za" #'proced-toggle-auto-update)
  :display
  ("\\*Proced\\*"
   (display-buffer-at-bottom)
   (window-height . 0.25))
  :init
  (setq proced-auto-update-interval 0.5)
  :config
  (with-eval-after-load "evil-collection"
    (evil-collection-proced-setup)))
#+end_src
** Calculator
Surprise, surprise Emacs comes with a calculator.

~calc-mode~ is a calculator system within Emacs that provides a
diverse array of mathematical operations.  It uses reverse polish
notation, but there is a standard infix algebraic notation mode so
don't be too shocked.  It can do a surprising amount of stuff, such
as:
+ finding derivatives/integrals of generic equations
+ matrix operations
+ finding solutions for equations, such as for finite degree multi
  variable polynomials

It also has this thing called embedded mode.  This allows one to
perform computation within a non ~calc-mode~ buffer.  Surround any
equation with dollar signs (such as 2^20, for example) and call
~(calc-embedded)~ with your cursor on it to compute it.  It'll replace
the equation with the result it computed.

Say I want to find the 4th power of 2 cos I'm writing some bit
manipulation code and I need to set the 4th bit of some variable to 1.
Instead of computing it outside of my editor then copying the result
back in, I can just do it within Emacs.  Pretty nifty, right?

#+begin_src emacs-lisp
(use-package calc
  :defer t
  :display
  ("*Calculator*"
   (display-buffer-at-bottom)
   (window-height . 0.18))
  :general
  (app-leader
    "c" #'calc-dispatch)
  :init
  (setq calc-algebraic-mode t)
  :config
  (with-eval-after-load "evil-collection"
    (evil-collection-calc-setup)))
#+end_src
** Zone
Of course Emacs has a cool screensaver software.

#+begin_src emacs-lisp
(use-package zone-matrix
  :straight t
  :defer t
  :commands (zone)
  :general
  (leader
    "z" #'zone)
  :init
  (setq zone-programs
        [zone-pgm-drip
         zone-pgm-drip-fretfully
         zone-pgm-martini-swan-dive
         zone-pgm-stress
         zone-pgm-random-life]))
#+end_src
** (Wo)man
Man pages are the user manuals for most software on Linux.  Really
useful when writing code for Un*x systems, though they can be very
verbose.

2023-08-17: `Man-notify-method' is the reason the `:display' record
doesn't work here.  I think it's to do with how Man pages are rendered
or something, but very annoying as it's a break from standards!
#+begin_src emacs-lisp
(use-package man
  :defer t
  :init
  (setq Man-notify-method 'pushy)
  :display
  ("^\\*Man.*"
   (display-buffer-reuse-mode-window display-buffer-same-window))
  :general
  (file-leader
    "m" #'man) ;; kinda like "find man page"
  (nmmap
    :keymaps 'Man-mode-map
    "RET" #'man-follow))
#+end_src
** WAIT gif-screencast
:PROPERTIES:
:header-args:emacs-lisp: :tangle no
:END:
Little application that uses =gifsicle= to make essentially videos of
Emacs.  Useful for demonstrating features.
#+begin_src emacs-lisp
(use-package gif-screencast
  :straight t
  :general
  (app-leader
    "x" #'gif-screencast-start-or-stop)
  :init
  (setq gif-screencast-output-directory (expand-file-name "~/Media/emacs/")))
#+end_src
** Image-mode
Image mode, for viewing images.  Supports tons of formats, easy to use
and integrates slickly into image-dired.  Of course,
#+begin_src emacs-lisp
(use-package image-mode
  :defer t
  :general
  (nmmap
    :keymaps 'image-mode-map
    "+" #'image-increase-size
    "-" #'image-decrease-size
    "p" #'image-animate
    "P" #'image-animate-set-speed
    "h" #'image-backward-hscroll
    "j" #'image-next-line
    "k" #'image-previous-line
    "l" #'image-forward-hscroll))
#+end_src
** WAIT ERC
:PROPERTIES:
:header-args:emacs-lisp: :tangle no
:END:
#+begin_src emacs-lisp
(use-package erc
  :defer t
  :init
  (setq erc-server "irc.libera.chat"
        erc-nick "oreodave"
        erc-buffer-display "current"))
#+end_src
** mpv
My [[file:elisp/mpv.el][custom mpv module]] for opening videos in
Emacs.

#+begin_src emacs-lisp
(use-package mpv
  :defer t
  :load-path "elisp/"
  :general
  (app-leader
    "v" #'mpv-open-video))
#+end_src
* Text modes
Standard packages and configurations for text-mode and its derived
modes.
** Flyspell
Flyspell allows me to quickly spell check text documents.  I use
flyspell primarily in org mode, as that is my preferred prose writing
software, but I also need it in commit messages and so on.  So
flyspell-mode should be hooked to text-mode.
#+begin_src emacs-lisp
(use-package flyspell
  :straight t
  :defer t
  :hook (text-mode-hook . flyspell-mode)
  :general
  (nmmap
    :keymaps 'text-mode-map
    (kbd "M-C") #'flyspell-correct-word-before-point
    (kbd "M-c") #'flyspell-auto-correct-word)
  (mode-leader
    "s" #'flyspell-mode))
#+end_src
** Undo tree
Undo tree sits on top of the incredible Emacs undo capabilities.
Provides a nice visual for edits and a great way to produce branches
of edits.  Also allows saving of undo trees, which makes Emacs a quasi
version control system in and of itself!  The only extra necessary
would be describing changes...
#+begin_src emacs-lisp
(use-package undo-tree
  :demand t
  :straight t
  :general
  (leader
    "u" #'undo-tree-visualize)
  :init
  (setq undo-tree-auto-save-history t
        undo-tree-history-directory-alist backup-directory-alist)
  :config
  (global-undo-tree-mode))
#+end_src
** Whitespace
Deleting whitespace, highlighting when going beyond the 80th character
limit, all good stuff.  I don't want to highlight whitespace for
general mode categories (Lisp shouldn't really have an 80 character
limit), so set it for specific modes need the help.

#+begin_src emacs-lisp
(use-package whitespace
  :defer t
  :general
  (nmmap
    "M--"   #'whitespace-cleanup)
  (mode-leader
    "w" #'whitespace-mode)
  :hook
  (before-save-hook  . whitespace-cleanup)
  ((c-mode-hook c++-mode-hook haskell-mode-hook python-mode-hook org-mode-hook text-mode-hook)
   . whitespace-mode)
  :init
  (setq whitespace-line-column nil
        whitespace-style '(face empty spaces tabs newline trailing lines-char
                                tab-mark)))
#+end_src
** Filling and displaying fills
The fill-column is the number of characters that should be in a single
line of text before doing a hard wrap.  The default case is 80
characters for that l33t Unix hard terminal character limit.  I like
different fill-columns for different modes: text modes should really
use 70 fill columns while code should stick to 80.
#+begin_src emacs-lisp
(use-package emacs
  :init
  (setq-default fill-column 80)
  (add-hook 'text-mode-hook  (proc (setq-local fill-column 70)))
  :hook
  (text-mode-hook . auto-fill-mode)
  ((c-mode-hook c++-mode-hook haskell-mode-hook python-mode-hook
                org-mode-hook text-mode-hook)
   . display-fill-column-indicator-mode))
#+end_src
** Show-paren-mode
Show parenthesis for Emacs
#+begin_src emacs-lisp
(add-hook 'prog-mode-hook #'show-paren-mode)
#+end_src
** Smartparens
Smartparens is a smarter electric-parens, it's much more aware of
context and easier to use.
#+begin_src emacs-lisp
(use-package smartparens
  :straight t
  :defer t
  :hook
  (prog-mode-hook . smartparens-mode)
  (text-mode-hook . smartparens-mode)
  :config
  (setq sp-highlight-pair-overlay nil
        sp-highlight-wrap-overlay t
        sp-highlight-wrap-tag-overlay t)

  (let ((unless-list '(sp-point-before-word-p
                       sp-point-after-word-p
                       sp-point-before-same-p)))
    (sp-pair "'"  nil :unless unless-list)
    (sp-pair "\"" nil :unless unless-list))
  (sp-local-pair sp-lisp-modes "(" ")" :unless '(:rem sp-point-before-same-p))
  (require 'smartparens-config))
#+end_src
** Thesaurus
=le-thesaurus= is a great extension for quickly searching up words for
synonyms or antonyms.  I may need it anywhere so I bind it to all
keymaps.  Same with dictionary searching.
#+begin_src emacs-lisp
(use-package le-thesaurus
  :straight t
  :defer t
  :display
  ("\\*Dictionary\\*"
   (display-buffer-reuse-window display-buffer-same-window)
   (reusable-frames . t))
  :init
  (setq dictionary-server "dict.org")
  :general
  (search-leader
    :infix "w"
    "s" #'le-thesaurus-get-synonyms
    "a" #'le-thesaurus-get-antonyms
    "d" #'dictionary-search))
#+end_src
* Programming packages
Packages that help with programming in general, providing IDE like
capabilities.
** Eldoc
Eldoc presents documentation to the user upon placing ones cursor upon
any symbol.  This is very useful when programming as it:
- presents the arguments of functions while writing calls for them
- presents typing and documentation of variables

Eldoc box makes the help buffer a hovering box instead of printing it
in the minibuffer.  A lot cleaner.

2024-05-31: Eldoc box is a bit useless now that I'm not using frames.
I prefer the use of the minibuffer for printing documentation now.
#+begin_src emacs-lisp
(use-package eldoc
  :defer t
  :hook (prog-mode-hook . eldoc-mode)
  :init
  (global-eldoc-mode 1)
  :general
  (leader
    "h>" #'eldoc-doc-buffer))
#+end_src
** Flycheck
Flycheck is the checking system for Emacs.  I don't necessarily like
having all my code checked all the time, so I haven't added a hook to
prog-mode as it would be better for me to decide when I want checking
and when I don't.

I've added it to C/C++ mode because I use them regularly and flycheck
has very little overhead to work there.
#+begin_src emacs-lisp
(use-package flycheck
  :straight t
  :defer t
  :commands (flycheck-mode flycheck-list-errors)
  :hook
  (c-mode-hook   . flycheck-mode)
  (c++-mode-hook . flycheck-mode)
  :general
  (mode-leader
    "f" #'flycheck-mode)
  (code-leader
    "x" #'flycheck-list-errors
    "j" #'flycheck-next-error
    "k" #'flycheck-previous-error)
  :display
  ("\\*Flycheck.*"
   (display-buffer-at-bottom)
   (window-height . 0.25))
  :init
  (setq-default flycheck-check-syntax-automatically '(save idle-change new-line mode-enabled))
  :config
  (with-eval-after-load "evil-collection"
    (evil-collection-flycheck-setup)))
#+end_src
** Eglot
Eglot is package to communicate with LSP servers for better
programming capabilities.  Interactions with a server provide results
to the client, done through JSON.

NOTE: Emacs 28.1 comes with better JSON parsing, which makes Eglot
much faster.

2023-03-26: I've found Eglot to be useful sometimes, but many of the
projects I work on don't require a heavy server setup to efficiently
edit and check for errors; Emacs provides a lot of functionality.  So
by default I've disabled it, using =M-x eglot= to startup the LSP
server when I need it.

2024-06-27: In projects where I do use eglot and I know I will need it
regardless of file choice, I prefer setting it at the dir-local level
via an eval form.  So I add to the safe values for the eval variable
to be set.
#+begin_src emacs-lisp
(use-package eglot
  :defer t
  :general
  (code-leader
    :keymaps 'eglot-mode-map
    "f" #'eglot-format
    "a" #'eglot-code-actions
    "r" #'eglot-rename
    "R" #'eglot-reconnect)
  :init
  (setq eglot-stay-out-of '(flymake)
        eglot-ignored-server-capabilities '(:documentHighlightProvider
                                            :documentOnTypeFormattingProvider
                                            :inlayHintProvider))
  (add-to-list 'safe-local-variable-values '(eval eglot-ensure))
  :config
  (add-to-list 'eglot-server-programs '((c++-mode c-mode) "clangd")))
#+end_src
*** Flycheck-Eglot
By default Eglot uses the integrated flymake package for error
reporting.  I don't mind flymake, and I think an integrated solution
which doesn't rely on external packages is always a great idea.
However, I just personally prefer flycheck and it's become part of my
mental model when programming.  So here's a package which will
integrate flycheck into Eglot's error reporting.

(Funny but also kind of depressing is this issue in Eglot where
someone requested this integration, which caused a bit of a flame war.
People are stupid.
[[https://github.com/joaotavora/eglot/issues/42][no opinion on
flymake]])
#+begin_src emacs-lisp
(use-package flycheck-eglot
  :straight t
  :after (flycheck eglot)
  :hook (eglot-managed-mode-hook . flycheck-eglot-mode))
#+end_src
** Indentation
By default, turn off tabs and set the tab width to two.
#+begin_src emacs-lisp
(setq-default indent-tabs-mode nil
              tab-width 2)
#+end_src

However, if necessary later, define a function that may activate tabs locally.
#+begin_src emacs-lisp
(defun +oreo/use-tabs ()
  (interactive)
  (setq-local indent-tabs-mode t))
#+end_src
** Highlight todo items
TODO items are highlighted in org-mode, but not necessarily in every
mode.  This minor mode highlights all TODO like items via a list of
strings to match.  It also configures faces to use when highlighting.
I hook it to prog-mode.

#+begin_src emacs-lisp
(use-package hl-todo
  :straight t
  :after prog-mode
  :hook (prog-mode-hook . hl-todo-mode)
  :init
  (setq hl-todo-keyword-faces
        '(("TODO"  . "#E50000")
          ("WIP"   . "#ffa500")
          ("NOTE"  . "#00CC00")
          ("FIXME" . "#d02090"))))
#+end_src
** Hide-show mode
Turn on ~hs-minor-mode~ for all prog-mode.  This provides folds for
free.
#+begin_src emacs-lisp
(use-package hideshow
  :defer t
  :hook (prog-mode-hook . hs-minor-mode))
#+end_src
** Aggressive indenting
Essentially my dream editing experience: when I type stuff in, try and
indent it for me on the fly.  Just checkout the
[[https://github.com/Malabarba/aggressive-indent-mode][page]], any
description I give won't do it justice.

#+begin_src emacs-lisp
(use-package aggressive-indent
  :straight t
  :demand t
  :config
  (add-multiple-to-list aggressive-indent-excluded-modes
                        'c-mode 'c++-mode 'cc-mode
                        'asm-mode)
  (global-aggressive-indent-mode))
#+end_src
** Compilation
Compilation mode is an incredibly useful subsystem of Emacs which
allows one to run arbitrary commands.  If those commands produce
errors (particularly errors that have a filename, column and line)
compilation-mode can colourise these errors and help you navigate to
them.

Here I add some bindings and a filter which colourises the output of
compilation mode for ANSI escape sequences; the eyecandy is certainly
nice but it's very useful when dealing with tools that use those codes
so you can actually read the text.
#+begin_src emacs-lisp
(use-package compile
  :defer t
  :general
  (leader
    "j" #'next-error
    "k" #'previous-error)
  (code-leader
    "c" #'compile
    "C" #'recompile)
  (nmmap
    :keymaps 'compilation-mode-map
    "c" #'recompile)
  (general-def
    :keymaps 'compilation-mode-map
    "g" nil) ;; by default this is recompile
  :display
  ("\\*compilation\\*"
   (display-buffer-reuse-window display-buffer-at-bottom)
   (reusable-frames . t)
   (window-height . 0.25))
  :init
  (setq compilation-scroll-output 'first-error
        compilation-context-lines nil
        next-error-highlight 'fringe-arrow)
  :config
  (add-hook 'compilation-filter-hook #'ansi-color-compilation-filter))
#+end_src
** xref
Find definitions, references and general objects using tags without
external packages.  Provided by default in Emacs and just requires a
way of generating a =TAGS= file for your project.  Helps with minimal
setups for programming without heavier packages like [[*Eglot][Eglot]].
#+begin_src emacs-lisp
(use-package xref
  :defer t
  :display
  ("\\*xref\\*"
   (display-buffer-at-bottom)
   (inhibit-duplicate-buffer . t)
   (window-height . 0.25))
  :general
  (code-leader
    "t" '(nil :which-key "Tags"))
  (code-leader
    :infix "t"
    "t" #'xref-find-apropos
    "d" #'xref-find-definitions
    "r" #'xref-find-references)
  (nmmap
    :keymaps 'xref--xref-buffer-mode-map
    "RET" #'xref-goto-xref
    "J" #'xref-next-line
    "K" #'xref-prev-line
    "g" #'xref-revert-buffer
    "q" #'quit-window))
#+end_src
** Project.el
An inbuilt solution for creating and managing projects that doesn't
require a dependency.  Where possible we should try to use Emacs
defaults (admittedly this is a philosophy I've only recently adopted)
so when setting up a new computer it takes a bit less time.

Here I write a TAGS command, mimicking projectile's one, so I can
quickly generate them in C/C++ projects.

#+begin_src emacs-lisp
(use-package project
  :defer t
  :general
  (general-def
    :keymaps 'project-prefix-map
    "R" #'+project/generate-tags)
  :config
  (defun +project/generate-tags ()
    (interactive)
    (let ((project (project-current)))
      (if (not project)
          (message "+project/generate-tags: Not in project.")
        (let ((tags-file (concat (project-root project) "TAGS"))
              (files (format "%s" (project-files project))))
          (set-process-sentinel
           (start-process-shell-command
            "PROJECT-GENERATE-TAGS"
            "*gen-tags*"
            (format "ctags -Re -f %s %s"
                    tags-file
                    (substring files 1 (- (length files) 1))))
           (lambda (p event)
             (when (string= event "finished\n")
               (visit-tags-table (concat (project-root (project-current)) "TAGS"))
               (message "Finished generating tags!")))))))))
#+end_src
** devdocs
#+begin_src emacs-lisp
(use-package devdocs
  :straight t
  :defer t
  :general
  (file-leader
    "d" #'devdocs-lookup))
#+end_src
** rainbow-delimiters
Makes colours delimiters (parentheses) based on their depth in an
expression.  Rainbow flag in your Lisp source code.
#+begin_src emacs-lisp
(use-package rainbow-delimiters
  :defer t
  :straight t
  :general
  (mode-leader "r" #'rainbow-delimiters-mode)
  :hook
  ((lisp-mode-hook emacs-lisp-mode-hook racket-mode-hook) . rainbow-delimiters-mode))
#+end_src
* Org mode
Org is, at its most basic, a markup language.  =org-mode= is a major
mode for Emacs to interpret org buffers.  org-mode provides a lot of
capabilities, some are:
+ A complete table based spreadsheet system, with formulas (including
  [[*Calculator][calc-mode]] integration)
+ Code blocks with proper syntax highlighting and editing experience
  + Evaluation
  + Export of code blocks to a variety of formats
  + Export of code blocks to a code file (so called "tangling", which
    is what occurs in this document)
+ Feature complete scheduling system with [[*Calendar][calendar]]
  integration
  + A clock-in system to time tasks
+ TODO system
+ Export to a variety of formats or make your own export engine using
  the org AST.
+ Inline $\LaTeX$, with the ability to render the fragments on
  demand within the buffer
+ Links to a variety of formats:
  + Websites (via http or https)
  + FTP
  + SSH
  + Files (even to a specific line)
  + Info pages

I'd argue this is a bit more than a markup language.  Like
[[*Magit][Magit]], some use Emacs just for this system.
** Org Essentials
Org has a ton of settings to tweak, which change your experience quite
a bit.  Here are mine, but this took a lot of just reading other
people's configurations and testing.  I don't do a good job of
explaining how this works in all honesty, but it works well for me so
I'm not very bothered.

+ By default =~/Text= is my directory for text files.  I actually have
  a repository that manages this directory for agenda files and other
  documents
+ Indentation in file should not be allowed, i.e. text indentation, as
  that forces other editors to read it a certain way as well.  It's
  obtrusive hence it's off.
+ Org startup indented is on by default as most documents do benefit
  from the indentation, but I do turn it off for some files via
  ~#+startup:noindent~
+ When opening an org document there can be a lot of headings, so I
  set folding to just content
+ Org documents can also have a lot of latex previews, which make
  opening some after a while a massive hassle.  If I want to see the
  preview, I'll do it myself, so turn it off.
+ Org manages windowing itself, to some extent, so I set those options
  to be as unobtrusive as possible
+ Load languages I use in =src= blocks in org-mode (Emacs-lisp for
  this configuration, C and Python)

#+begin_src emacs-lisp
(use-package org
  :straight t
  :defer t
  :init
  (setq org-directory "~/Text/"
        org-adapt-indentation nil
        org-indent-mode nil
        org-startup-indented t
        org-startup-folded 'content
        org-startup-with-latex-preview nil
        org-imenu-depth 10
        org-src-window-setup 'current-window
        org-indirect-buffer-display 'current-window
        org-link-frame-setup '((vm . vm-visit-folder-other-frame)
                               (vm-imap . vm-visit-imap-folder-other-frame)
                               (file . find-file))
        org-babel-load-languages '((emacs-lisp . t)
                                   (lisp . t)
                                   (shell . t))))
#+end_src
** Org Latex
Org mode has deep integration with latex, can export to PDF and even
display latex fragments in the document directly.  I setup the
pdf-process, code listing options via minted and the format options
for latex fragments.
#+begin_src emacs-lisp
(use-package org
  :defer t
  :init
  (setq org-format-latex-options
        '(:foreground default :background default :scale 2
          :html-foreground "Black" :html-background "Transparent"
          :html-scale 1.0 :matchers ("begin" "$1" "$" "$$" "\\(" "\\["))
        org-latex-src-block-backend 'minted
        org-latex-minted-langs '((emacs-lisp "common-lisp")
                                 (ledger "text")
                                 (cc "c++")
                                 (cperl "perl")
                                 (shell-script "bash")
                                 (caml "ocaml"))
        org-latex-packages-alist '(("" "minted"))
        org-latex-pdf-process
        (list (concat "latexmk -f -bibtex -pdf "
                      "-shell-escape -%latex -interaction=nonstopmode "
                      "-output-directory=%o %f"))
        org-latex-minted-options
        '(("style" "colorful")
          ("linenos")
          ("frame" "single")
          ("mathescape")
          ("fontfamily" "courier")
          ("samepage" "false")
          ("breaklines" "true")
          ("breakanywhere" "true"))))
#+end_src
** Org Core Variables
Tons of variables for org-mode, including a ton of latex ones.  Can't
really explain because it sets up quite a lot of local stuff.  Also I
copy pasted the majority of this, tweaking it till it felt good.  Doom
Emacs was very helpful here.
#+begin_src emacs-lisp
(use-package org
  :defer t
  :init
  (setq org-edit-src-content-indentation 0
        org-eldoc-breadcrumb-separator " → "
        org-enforce-todo-dependencies t
        org-export-backends '(ascii html latex odt icalendar)
        org-fontify-quote-and-verse-blocks t
        org-fontify-whole-heading-line t
        org-footnote-auto-label t
        org-goto-interface 'outline
        org-hide-emphasis-markers nil
        org-hide-leading-stars t
        org-image-actual-width nil
        org-imenu-depth 10
        org-link-descriptive nil
        org-priority-faces '((?A . error) (?B . warning) (?C . success))
        org-refile-targets '((nil . (:maxlevel . 2)))
        org-tags-column 0
        org-todo-keywords '((sequence "TODO" "WIP" "DONE")
                            (sequence "PROJ" "WAIT" "COMPLETE"))
        org-use-sub-superscripts '{}))
#+end_src
** Org Core Functionality
Hooks, prettify-symbols and records for auto insertion.
#+begin_src emacs-lisp
(use-package org
  :defer t
  :hook
  (org-mode-hook . prettify-symbols-mode)
  :display
  ("\\*Org Src.*"
   (display-buffer-same-window))
  :auto-insert
  (("\\.org\\'" . "Org skeleton")
   "Enter title: "
   "#+title: " str | (buffer-file-name) "\n"
   "#+author: " (read-string "Enter author: ") | user-full-name "\n"
   "#+description: " (read-string "Enter description: ") | "Description" "\n"
   "#+date: " (format-time-string "%Y-%m-%d" (current-time)) "\n"
   "* " _))
#+end_src
** Org Core Bindings
Some bindings for org mode.
#+begin_src emacs-lisp
(use-package org
  :defer t
  :general
  (file-leader
    "l" #'org-store-link
    "i" #'org-insert-last-stored-link)
  (code-leader
    :keymaps 'emacs-lisp-mode-map
    "D" #'org-babel-detangle)
  (local-leader
    :keymaps 'org-mode-map
    "l" '(nil :which-key "Links")
    "'" '(nil :which-key "Tables")
    "c" '(nil :which-key "Clocks")
    "r" #'org-refile
    "d" #'org-date-from-calendar
    "t" #'org-todo
    "," #'org-priority
    "T" #'org-babel-tangle
    "i" #'org-insert-structure-template
    "p" #'org-latex-preview
    "s" #'org-property-action
    "e" #'org-export-dispatch
    "o" #'org-edit-special)
  (local-leader
    :keymaps 'org-mode-map
    :infix "l"
    "i" #'org-insert-link
    "l" #'org-open-at-point
    "f" #'org-footnote-action)
  (local-leader
    :keymaps 'org-mode-map
    :infix "'"
    "a" #'org-table-align
    "c" #'org-table-create
    "f" #'org-table-edit-formulas
    "t" #'org-table-toggle-coordinate-overlays
    "s" #'org-table-sum
    "e" #'org-table-calc-current-TBLFM
    "E" #'org-table-eval-formula))
#+end_src
** Searching org files
The default ~imenu~ support for Org-mode is god-awful.  ~Imenu~ for
org-mode should show me a list of headings and provide a
completing-read interface to search them.

[[*Counsel][Counsel]] has me covered for this as I can just provide it
a regex as an initial prompt to narrow the candidates down to just the
headings then let the user go from there.  I use ~swiper~ when
considering just the local file (a la ~imenu~) and ~counsel-rg~ to
search multiple org-files.

The cherry on top is ~+org/search-config-headings~ which searches the
org files in ~user-emacs-directory~ and provides the headings for
them.  This allows me to search my configuration pretty quickly.
#+begin_src emacs-lisp
(use-package counsel
  :defer t
  :commands (+org/swiper-goto
             +org/search-headings-dir)
  :general
  (file-leader
    "P" (proc (interactive)
              (+org/search-headings-dir (file-name-directory user-emacs-directory)
                                        "--max-depth=1"))
    "T" (proc (interactive)
              (+org/search-headings-dir (file-name-directory org-directory)
                                        "--max-depth=2")))
  (search-leader
    :keymaps 'org-mode-map
    "I" #'+org/search-headings)
  (nmmap
    :keymaps 'org-mode-map
    [remap imenu] #'+org/swiper-goto)
  :config
  (defvar +org/heading-regexp "^[\\*]+[ ] ")

  (defun +org/swiper-goto ()
    (interactive)
    (counsel-grep-or-swiper +org/heading-regexp))

  (defun +org/search-headings-dir (directory &optional rg-args)
    "Searches DIRECTORY for org headings via counsel-rg."
    (counsel-rg +org/heading-regexp directory rg-args)))
#+end_src
** Org Agenda
Org agenda provides a nice viewing for schedules.  With org mode it's
a very tidy way to manage your time.
#+begin_src emacs-lisp
(use-package org-agenda
  :defer t
  :init
  (defconst +org/agenda-root "~/Text"
    "Root directory for all agenda files")
  (setq org-agenda-files (list (expand-file-name +org/agenda-root))
        org-agenda-window-setup 'current-window
        org-agenda-skip-deadline-prewarning-if-scheduled t
        org-agenda-skip-scheduled-if-done t
        org-agenda-skip-deadline-if-done t
        org-agenda-start-with-entry-text-mode nil)
  :config
  (evil-set-initial-state 'org-agenda-mode 'normal)
  :general
  (file-leader
    "a" `(,(proc (interactive)
                 (find-file (completing-read "Enter directory: " org-agenda-files nil t)))
          :which-key "Open agenda directory"))
  (app-leader
    "a" #'org-agenda)
  (nmmap
    :keymaps 'org-agenda-mode-map
    "zd" #'org-agenda-day-view
    "zw" #'org-agenda-week-view
    "zm" #'org-agenda-month-view
    "gd" #'org-agenda-goto-date
    "RET" #'org-agenda-switch-to
    "J" #'org-agenda-later
    "K" #'org-agenda-earlier
    "t" #'org-agenda-todo
    "." #'org-agenda-goto-today
    "," #'org-agenda-goto-date
    "q" #'org-agenda-quit
    "r" #'org-agenda-redo))
#+end_src
** Org capture
Org capture provides a system for quickly "capturing" some information
into an org file.  A classic example is creating a new TODO in a
todo file, where the bare minimum to record one is:
+ where was it recorded?
+ when was it recorded?
+ what is it?
Org capture provides a way to do that seamlessly without opening the
todo file directly.
#+begin_src emacs-lisp
(use-package org-capture
  :defer t
  :init
  (setq
   org-default-notes-file (concat org-directory "todo.org")
   org-capture-templates
   '(("t" "Todo" entry
      (file "")
      "* TODO %?
%T
%a")))
  :general
  (leader
    "C" #'org-capture)
  (nmmap
    :keymaps 'org-capture-mode-map
    "ZZ" #'org-capture-finalize
    "ZR" #'org-capture-refile
    "ZQ" #'org-capture-kill))
#+end_src
** Org clock-in
Org provides a nice timekeeping system that allows for managing how
much time is taken per task.  It even has an extensive reporting
system to see how much time you spend on specific tasks or overall.
#+begin_src emacs-lisp
(use-package org-clock
  :after org
  :init
  (defvar +org/clock-out-toggle-report nil
    "Non-nil means update the first clock report in the file every
time a clock out occurs.")
  :config
  (advice-add #'org-clock-out
              :after
              (proc (interactive)
                    (if +org/clock-out-toggle-report
                        (org-clock-report t))))
  :general
  (local-leader
    :keymaps 'org-mode-map
    :infix "c"
    "d" #'org-clock-display
    "c" #'org-clock-in
    "o" #'org-clock-out
    "r" #'org-clock-report
    "t" (proc (interactive)
              (setq-local +org/clock-out-toggle-report
                          (not +org/clock-out-toggle-report)))))
#+end_src
** Org compile to PDF on save
If ~+org/compile-to-pdf-on-save-p~ is non-nil, then compile to
\(\LaTeX\) and run an async process to compile it to a PDF.  Doesn't
make Emacs hang (like ~org-latex-export-to-pdf~) and doesn't randomly
crash (like the async handler for org-export).
#+begin_src emacs-lisp
(use-package org
  :defer t
  :init
  (defvar +org/compile-to-pdf-on-save-p
    nil
    "Non-nil to activate compile functionality.")
  :general
  (local-leader
    :keymaps 'org-mode-map
    "C" (proc (interactive)
              (if (+org/compile-to-pdf-on-save-f)
                  (setq-local +org/compile-to-pdf-on-save-p nil)
                (setq-local +org/compile-to-pdf-on-save-p t))))
  :config
  (+oreo/create-auto-save
   (and (eq major-mode 'org-mode) +org/compile-to-pdf-on-save-p)
   (start-process-shell-command
    "" "*pdflatex*"
    (concat "pdflatex -shell-escape " (org-latex-export-to-latex)))))
#+end_src
** WAIT Org ref
:PROPERTIES:
:header-args:emacs-lisp: :tangle no
:END:
For bibliographic stuff in $\LaTeX$ export.
#+begin_src emacs-lisp
(use-package org-ref
  :straight t
  :defer t
  :init
  (setq bibtex-files '("~/Text/bibliography.bib")
        bibtex-completion-bibliography '("~/Text/bibliography.bib")
        bibtex-completion-additional-search-fields '(keywords)))
#+end_src
*** Org ref ivy integration
Org ref requires ivy-bibtex to work properly with ivy, so we need to
set that up as well
#+begin_src emacs-lisp
(use-package ivy-bibtex
  :straight t
  :after org-ref
  :config
  (require 'org-ref-ivy))
#+end_src
** Org message
Org message allows for the use of org mode when composing mails,
generating HTML multipart emails.  This integrates the WYSIWYG
experience with mail in Emacs while also providing powerful text
features with basically no learning curve (as long as you've already
learnt the basics of org).

#+begin_src emacs-lisp
(use-package org-msg
  :straight t
  :hook
  (message-mode-hook . org-msg-mode)
  (notmuch-message-mode-hook . org-msg-mode)
  :config
  (setq org-msg-options "html-postamble:nil H:5 num:nil ^:{} toc:nil author:nil email:nil \\n:t tex:dvipng"
        org-msg-greeting-name-limit 3)

  (add-to-list 'org-msg-enforce-css
               '(img latex-fragment-inline
                     ((transform . ,(format "translateY(-1px) scale(%.3f)"
                                            (/ 1.0 (if (boundp 'preview-scale)
                                                       preview-scale 1.4))))
                      (margin . "0 -0.35em")))))
#+end_src
** Org for evil
Evil org for some nice bindings.
#+begin_src emacs-lisp
(use-package evil-org
  :straight t
  :defer t
  :hook (org-mode-hook . evil-org-mode)
  :general
  (nmmap
    :keymaps 'org-mode-map
    "TAB" #'org-cycle))
#+end_src
** Org reveal
Org reveal allows one to export org files as HTML presentations via
reveal.js.  Pretty nifty and it's easy to use.
#+begin_src emacs-lisp
(use-package ox-reveal
  :straight t
  :defer t
  :init
  (setq org-reveal-root "https://cdn.jsdelivr.net/npm/reveal.js"
        org-reveal-theme "sky"))
#+end_src
** Org superstar
Org superstar adds unicode symbols for headers, much better than the
default asterisks.
#+begin_src emacs-lisp
(use-package org-superstar
  :straight t
  :defer t
  :hook (org-mode-hook . org-superstar-mode))
#+end_src
** Org bookmark
I maintain a bookmarks file at =~/Text/bookmarks.org=.  I would like
the ability to construct new bookmarks and open bookmarks.  They may
be either articles I want to read, useful information documents or
just straight up youtube videos.  So I wrote a
[[file:elisp/org-bookmark.el][library]] myself which does the
appropriate dispatching and work for me.  Pretty sweet!

Also I define a template for org-capture here for bookmarks and add it
to the list ~org-capture-templates~.

#+begin_src emacs-lisp
(use-package org-bookmark
  :defer t
  :load-path "elisp/"
  :general
  (file-leader
    "b" #'org-bookmark/open-bookmark)
  :init
  (with-eval-after-load "org-capture"
    (add-to-list
     'org-capture-templates
     '("b" "Bookmark" entry
       (file "bookmarks.org")
       "* %? :bookmark:
%T
%^{url|%x}p
"
       ))))
#+end_src
* Languages
For a variety of (programming) languages Emacs comes with default
modes but this configures them as well as pulls any modes Emacs
doesn't come with.
** Makefile
Defines an auto-insert for Makefiles.  Assumes C but it's very easy to
change it for C++.
#+begin_src emacs-lisp
(use-package make-mode
  :defer t
  :auto-insert
  (("[mM]akefile\\'" . "Makefile skeleton")
   ""
	 "CC=gcc
OUT=main.out
LIBS=
ARGS=

RELEASE=0
GFLAGS=-Wall -Wextra -Werror -Wswitch-enum -std=c11
DFLAGS=-ggdb -fsanitize=address -fsanitize=undefined
RFLAGS=-O3
DEPFLAGS=-MT $@ -MMD -MP -MF
ifeq ($(RELEASE), 1)
CFLAGS=$(GFLAGS) $(RFLAGS)
else
CFLAGS=$(GFLAGS) $(DFLAGS)
endif

SRC=src
DIST=build
CODE=$(addprefix $(SRC)/, ) # add source files here
OBJECTS=$(CODE:$(SRC)/%.c=$(DIST)/%.o)
DEPDIR:=$(DIST)/dependencies
DEPS:=$(CODE:$(SRC)/%.c=$(DEPDIR):%.d) $(DEPDIR)/main.d

.PHONY: all
all: $(OUT)

$(OUT): $(DIST)/$(OUT)

$(DIST)/$(OUT): $(OBJECTS) $(DIST)/main.o | $(DIST)
	$(CC) $(CFLAGS) $^ -o $@ $(LIBS)

$(DIST)/%.o: $(SRC)/%.c | $(DIST) $(DEPDIR)
	$(CC) $(CFLAGS) $(DEPFLAGS) $(DEPDIR)/$*.d -c $< -o $@ $(LIBS)

.PHONY: run
run: $(DIST)/$(OUT)
	./$^ $(ARGS)

.PHONY:
clean:
	rm -rfv $(DIST)/*

$(DIST):
	mkdir -p $(DIST)

$(DEPDIR):
	mkdir -p $(DEPDIR)

-include $(DEPS)
"
   _))
#+end_src
** WAIT SQL
:PROPERTIES:
:header-args:emacs-lisp: :tangle no
:END:
The default SQL package provides support for connecting to common
database types (sqlite, mysql, etc) for auto completion and query
execution.  I don't use SQL currently but whenever I need it it's
there.
#+begin_src emacs-lisp
(use-package sql
  :defer t
  :init
  (setq sql-display-sqli-buffer-function nil))
#+end_src
** WAIT Ada
:PROPERTIES:
:header-args:emacs-lisp: :tangle no
:END:
Check out [[file:elisp/ada-mode.el][ada-mode]], my custom ~ada-mode~
that replaces the default one.  This mode just colourises stuff, and
uses eglot and a language server to do the hard work.

#+begin_src emacs-lisp
(use-package ada-mode
  :load-path "elisp/"
  :defer t
  :config
  (with-eval-after-load "eglot"
    (add-hook 'ada-mode-hook #'eglot)))
#+end_src
** NHexl
Hexl-mode is the inbuilt package within Emacs to edit hex and binary
format buffers.  There are a few problems with hexl-mode though,
including an annoying prompt on /revert-buffer/.

Thus, nhexl-mode!  It comes with a few other improvements. Check out
the [[https://elpa.gnu.org/packages/nhexl-mode.html][page]] yourself.
#+begin_src emacs-lisp
(use-package nhexl-mode
  :straight t
  :defer t
  :mode ("\\.bin" "\\.out"))
#+end_src
** C/C++
Setup for C and C++ modes, using Emacs' default package: cc-mode.
*** cc-mode
Tons of stuff, namely:
+ ~auto-fill-mode~ for 80 char limit
+ Some keybindings to make evil statement movement easy
+ Lots of pretty symbols
+ Indenting options and a nice (for me) code style for C
+ Auto inserts to get a C file going
#+begin_src emacs-lisp
(use-package cc-mode
  :defer t
  :hook
  (c-mode-hook   . auto-fill-mode)
  (c++-mode-hook . auto-fill-mode)
  :general
  (:keymaps '(c-mode-map c++-mode-map)
   :states '(normal motion visual)
   "(" #'c-beginning-of-statement
   ")" #'c-end-of-statement
   "{" #'c-beginning-of-defun
   "}" #'c-end-of-defun)
  :init
  (setq-default c-basic-offset 2)
  (setq-default c-auto-newline nil)
  (setq-default c-default-style '((other . "user")))
  (defun +cc/copyright-notice ()
    (let* ((lines (split-string (+license/copyright-notice) "\n"))
           (copyright-line (car lines))
           (rest (cdr lines)))
      (concat
       "* "
       copyright-line
       "\n"
       (mapconcat
        #'(lambda (x)
            (if (string= x "")
                ""
              (concat " * " x)))
        rest
        "\n"))))
  :auto-insert
  (("\\.c\\'" . "C skeleton")
   ""
   "/" (+cc/copyright-notice) "\n\n"
   " * Created: " (format-time-string "%Y-%m-%d") "\n"
   " * Author: " user-full-name "\n"
   " * Description: " _ "\n"
   " */\n"
   "\n")
  (("\\.cpp\\'" "C++ skeleton")
   ""
   "/" (+cc/copyright-notice) "\n\n"
   " * Created: " (format-time-string "%Y-%m-%d") "\n"
   " * Author: " user-full-name "\n"
   " * Description: " _ "\n"
   " */\n"
   "\n")
  (("\\.\\([Hh]\\|hh\\|hpp\\|hxx\\|h\\+\\+\\)\\'" . "C / C++ header")
   (replace-regexp-in-string "[^A-Z0-9]" "_"
                             (string-replace "+" "P"
                                             (upcase
                                              (file-name-nondirectory buffer-file-name))))
   "/" (+cc/copyright-notice) "\n\n"
   " * Created: " (format-time-string "%Y-%m-%d") "\n"
   " * Author: " user-full-name "\n"
   " * Description: " _ "\n"
   " */\n\n"
   "#ifndef " str n "#define " str "\n\n" "\n\n#endif")
  :config
  (c-add-style
   "user"
   '((c-basic-offset . 2)
     (c-comment-only-line-offset . 0)
     (c-hanging-braces-alist (brace-list-open)
                             (brace-entry-open)
                             (substatement-open after)
                             (block-close . c-snug-do-while)
                             (arglist-cont-nonempty))
     (c-cleanup-list brace-else-brace)
     (c-offsets-alist
      (statement-block-intro . +)
      (substatement-open . 0)
      (access-label . -)
      (inline-open  . 0)
      (label . 0)
      (statement-cont . +)))))
#+end_src
*** Clang format
clang-format is a program that formats C/C++ files.  It's highly
configurable and quite fast.  I have a root configuration in my
Dotfiles (check it out
[[file:~/Dotfiles/ClangFormat/).clang-format][here]].

Clang format comes inbuilt with clang/LLVM, so it's quite likely to be
on your machine.

#+begin_src emacs-lisp
(use-package clang-format
  :load-path "/usr/share/clang/"
  :defer t
  :after cc-mode
  :commands (+code/clang-format-region-or-buffer
             clang-format-mode)
  :general
  (code-leader
    :keymaps '(c-mode-map c++-mode-map)
    "f" #'clang-format-buffer)
  :config
  (define-minor-mode clang-format-mode
    "On save formats the current buffer via clang-format."
    :lighter nil
    (let ((save-func (proc (interactive)
                           (clang-format-buffer))))
      (if clang-format-mode
          (add-hook 'before-save-hook save-func nil t)
        (remove-hook 'before-save-hook save-func t))))
  (defun +code/clang-format-region-or-buffer ()
    (interactive)
    (if (mark)
        (clang-format-region (region-beginning) (region-end))
      (clang-format-buffer))))
#+end_src
*** cc org babel
To ensure org-babel executes language blocks of C/C++, I need to load
it as an option in ~org-babel-load-languages~.
#+begin_src emacs-lisp
(use-package org
  :after cc-mode
  :init
  (org-babel-do-load-languages
   'org-babel-load-languages
   '((C . t))))
#+end_src
*** cc compile fsan
Sanitisers are a blessing for C/C++.  An additional runtime on top of
the executable which catches stuff like undefined behaviour or memory
leaks make it super easy to see where and how code is failing.
However, by default, Emacs' compilation-mode doesn't understand the
logs =fsanitize= makes so you usually have to manually deal with it
yourself.

Compilation mode uses regular expressions to figure out whether
something is an error and how to navigate to the file where that error
is located.  So adding support for =-fsanitize= is as simple as making
a regular expression which captures file names and digits
#+begin_src emacs-lisp
(use-package compile
  :after cc-mode
  :config
  (add-to-list 'compilation-error-regexp-alist-alist
               '(fsan "^    #[[:digit:]] 0x[[:alnum:]]+ in .*? \\(.*.c\\(pp\\)?\\):\\([[:digit:]]+\\):\\([[:digit:]]+\\)"
                      1 3 4))
  (add-to-list 'compilation-error-regexp-alist
               'fsan))
#+end_src
** WAIT D
:PROPERTIES:
:header-args:emacs-lisp: :tangle no
:END:
D is a systems level programming language with C-style syntax.  I
think it has some interesting ideas such as a toggleable garbage
collector.  Here I just install the D-mode package, enable ~org-babel~
execution of d-mode blocks and alias ~D-mode~ with ~d-mode~.

#+begin_src emacs-lisp
(use-package d-mode
  :defer t
  :straight t
  :config
  (fset 'D-mode 'd-mode)
  (with-eval-after-load "org-mode"
    (setf (alist-get 'd org-babel-load-languages) t)))
#+end_src
** Rust
#+begin_src emacs-lisp
(use-package rust-mode
  :straight t
  :defer t
  :general
  (code-leader
    :keymaps 'rust-mode-map
    "f" #'rust-format-buffer)
  (local-leader
    :keymaps 'rust-mode-map
    "c" #'rust-run-clippy)
  :init
  (setq rust-format-on-save t)
  (with-eval-after-load "eglot"
    (add-to-list 'eglot-server-programs '(rust-mode "rust-analyzer"))))
#+end_src
** Racket
A scheme with lots of stuff inside it.  Using it for a language design
book so it's useful to have some Emacs binds for it.
#+begin_src emacs-lisp
(use-package racket-mode
  :straight t
  :defer t
  :hook (racket-mode-hook . racket-xp-mode)
  :display
  ("\\*Racket REPL*"
   (display-buffer-at-bottom)
   (window-height . 0.25))
  :init
  (setq racket-documentation-search-location 'local)
  :general
  (nmap
    :keymaps 'racket-describe-mode-map
    "q" #'quit-window)
  (nmap
    :keymaps 'racket-mode-map
    "gr" #'racket-eval-last-sexp)
  (local-leader
    :keymaps '(racket-mode-map racket-repl-mode-map)
    "d" #'racket-repl-describe)
  (local-leader
    :keymaps 'racket-mode-map
    "r" #'racket-run
    "i" #'racket-repl
    "e" #'racket-send-definition
    "sr" #'racket-send-region
    "sd" #'racket-send-definition))
#+end_src
** WAIT CSharp
:PROPERTIES:
:header-args:emacs-lisp: :tangle no
:END:
Haven't used C# in a while, but Emacs is alright for it with
omnisharp.
#+begin_src emacs-lisp
(use-package csharp-mode
  :defer t)
#+end_src
** WAIT Java
:PROPERTIES:
:header-args:emacs-lisp: :tangle no
:END:
I kinda dislike Java, but if necessary I will code in it.  Just setup
a style and some pretty symbols.  You can use LSP to get cooler
features to be fair.
#+begin_src emacs-lisp
(use-package ob-java
  :defer t
  :config
  (with-eval-after-load "cc-mode"
    (c-add-style
     "java"
     '((c-basic-offset . 4)
       (c-comment-only-line-offset 0 . 0)
       (c-offsets-alist
        (inline-open . 0)
        (topmost-intro-cont . +)
        (statement-block-intro . +)
        (knr-argdecl-intro . 5)
        (substatement-open . 0)
        (substatement-label . +)
        (label . +)
        (statement-case-open . +)
        (statement-cont . +)
        (arglist-intro . c-lineup-arglist-intro-after-paren)
        (arglist-close . c-lineup-arglist)
        (brace-list-intro first c-lineup-2nd-brace-entry-in-arglist c-lineup-class-decl-init-+ +)
        (access-label . 0)
        (inher-cont . c-lineup-java-inher)
        (func-decl-cont . c-lineup-java-throws))))
    (add-to-list 'c-default-style '(java-mode . "java")))

  (with-eval-after-load "abbrev"
    (define-abbrev-table 'java-mode-abbrev-table nil)
    (add-hook 'java-mode-hook
              (proc (setq-local local-abbrev-table java-mode-abbrev-table)))))
#+end_src
** Haskell
Haskell is a static lazy functional programming language (what a
mouthful).  It's quite a beautiful language and really learning it will
change the way you think about programming.  However, my preferred
functional language is still unfortunately Lisp so no extra brownie
points there.

Here I configure the REPL for Haskell via the
~haskell-interactive-mode~.  I also load my custom package
[[file:elisp/haskell-multiedit.el][haskell-multiedit]] which allows a
user to create temporary ~haskell-mode~ buffers that, upon completion,
will run in the REPL.  Even easier than making your own buffer.
#+begin_src emacs-lisp
(use-package haskell-mode
  :straight t
  :defer t
  :hook
  (haskell-mode-hook . haskell-indentation-mode)
  (haskell-mode-hook . interactive-haskell-mode)
  :custom
  (haskell-interactive-prompt "[λ] ")
  (haskell-interactive-prompt-cont "{λ} ")
  (haskell-interactive-popup-errors nil)
  (haskell-stylish-on-save nil)
  (haskell-process-type 'auto)
  :general
  (shell-leader
    "h" #'haskell-interactive-bring)
  (local-leader
    :keymaps 'haskell-mode-map
    "l" #'haskell-process-load-or-reload
    "t" #'haskell-process-do-type)
  (local-leader
    :keymaps 'haskell-interactive-mode-map
    "c" #'haskell-interactive-mode-clear)
  (imap
    :keymaps 'haskell-interactive-mode-map
    "M-k" #'haskell-interactive-mode-history-previous
    "M-j" #'haskell-interactive-mode-history-next)
  :display
  ("\\*haskell.**\\*"
   (display-buffer-at-bottom)
   (window-height . 0.25))
  :config
  (load (concat user-emacs-directory "elisp/haskell-multiedit.el")))
#+end_src
** Python
Works well for python.  If you have ~pyls~ it should be on your path, so
just run eglot if you need.  But an LSP server is not necessary for a
lot of my time in python.  Here I also setup org-babel for python
source code blocks.
#+begin_src emacs-lisp
(use-package python
  :defer t
  :pretty
  (python-mode-hook
   ("None"   . "Ø")
   ("list"   . "ℓ")
   ("List"   . "ℓ")
   ("str"    . "𝕊")
   ("True"   . "⊨")
   ("False"  . "⊭")
   ("!"      . "¬")
   ("&&"     . "∧")
   ("||"     . "∨")
   ("for"    . "∀")
   ("print"  . "φ")
   ("lambda" . "λ")
   ("return" . "⟼")
   ("yield"  . "⟻"))
  :init
  (setq python-indent-offset 4)
  :config
  (with-eval-after-load "org-mode"
    (setf (alist-get 'python org-babel-load-languages) t)))
#+end_src
*** Python shell
Setup for python shell, including a toggle option
#+begin_src emacs-lisp
(use-package python
  :defer t
  :commands +python/toggle-repl
  :general
  (shell-leader
    "p" #'run-python)
  :display
  ("\\*Python\\*"
   (display-buffer-at-bottom)
   (window-height . 0.25)))
#+end_src
** YAML
YAML is a data language which is useful for config files.
#+begin_src emacs-lisp
(use-package yaml-mode
  :straight t)
#+end_src
** HTML/CSS/JS
Firstly, web mode for consistent colouring of syntax.
#+begin_src emacs-lisp
(use-package web-mode
  :straight t
  :defer t
  :mode ("\\.html" . web-mode)
  :mode ("\\.js"   . web-mode)
  :mode ("\\.css"  . web-mode)
  :custom
  ((web-mode-code-indent-offset 2)
   (web-mode-markup-indent-offset 2)
   (web-mode-css-indent-offset 2)))
#+end_src
*** Emmet
Emmet for super speed code writing.
#+begin_src emacs-lisp
(use-package emmet-mode
  :straight t
  :hook (web-mode-hook . emmet-mode)
  :general
  (imap
    :keymaps 'emmet-mode-keymap
    "TAB" #'emmet-expand-line
    "M-j" #'emmet-next-edit-point
    "M-k" #'emmet-prev-edit-point))
#+end_src
*** HTML Auto insert
#+begin_src emacs-lisp
(use-package web-mode
  :defer t
  :auto-insert
  (("\\.html\\'" . "HTML Skeleton")
   ""
   "<!doctype html>
<html lang=''>
  <head>
    <meta charset='utf-8'>
    <meta http-equiv='x-ua-compatible' content='ie=edge'>
    <title>"(read-string "Enter title: ") | """</title>
    <meta name='description' content='" (read-string "Enter description: ") | "" "'>
    <meta name='author' content='"user-full-name"'/>
    <meta name='viewport' content='width=device-width, initial-scale=1'>

    <link rel='apple-touch-icon' href='/apple-touch-icon.png'>
    <link rel='shortcut icon' href='/favicon.ico'/>
    <!-- Place favicon.ico in the root directory -->

  </head>
  <body>
    <!--[if lt IE 8]>
      <p class='browserupgrade'>
      You are using an <strong>outdated</strong> browser. Please
      <a href='http://browsehappy.com/'>upgrade your browser</a> to improve
      your experience.
      </p>
    <![endif]-->
"
   _
   "     </body>
</html>"))
#+end_src
*** WAIT Typescript
:PROPERTIES:
:header-args:emacs-lisp: :tangle no
:END:
A child language of javascript which compiles to it.
#+begin_src emacs-lisp
(use-package typescript-mode
  :straight t
  :defer t
  :init
  (setq typescript-indent-level 2))
#+end_src
** Scheme
Another Lisp but simpler than the rest.  A beauty of engineering and
fun to write programs in.
#+begin_src emacs-lisp
(use-package cmuscheme
  :display
  ("\\*scheme\\*"
   (display-buffer-reuse-window display-buffer-at-bottom)
   (window-height . 0.25))
  :general
  (local-leader
    :keymaps 'scheme-mode-map
    "t"  #'run-scheme
    "cc" #'scheme-compile-definition
    "cf" #'scheme-compile-file
    "cr" #'scheme-compile-region
    "sf" #'scheme-send-definition
    "sr" #'scheme-send-region
    "e" #'scheme-send-last-sexp))
#+end_src
** Common Lisp
Common Lisp is a dialect of Lisp, the most /common/ one around.  Emacs
comes with builtin Lisp support, of course, and it's really good in
comparison to literally everything else.  However, I wish it had a
better REPL...
*** Sly
Enter /SLY/.  Sly is a fork of /SLIME/ and is *mandatory* for lisp
development on Emacs.

Here I just setup Sly to use ~sbcl~.
#+begin_src emacs-lisp
(use-package sly
  :defer t
  :straight t
  :init
  (setq inferior-lisp-program "sbcl"
        sly-lisp-loop-body-forms-indentation 0)
  :display
  ("\\*sly-db"
   (display-buffer-at-bottom)
   (window-height . 0.5))
  ("\\*sly-"
   (display-buffer-at-bottom)
   (window-height . 0.25))
  :config
  (evil-set-initial-state 'sly-db-mode 'normal)
  (with-eval-after-load "org"
    (setq-default org-babel-lisp-eval-fn #'sly-eval))
  (with-eval-after-load "company"
    (add-hook 'sly-mrepl-hook #'company-mode))
  :general
  (shell-leader
    "s" #'sly)
  (nmap
    :keymaps 'lisp-mode-map
    "gr" #'sly-eval-buffer
    "gd" #'sly-edit-definition
    "gR" #'sly-who-calls)
  (local-leader
    :keymaps 'lisp-mode-map
    "a" '(sly-apropos :which-key "Apropos")
    "d" '(sly-describe-symbol :which-key "Describe symbol")
    "D" '(sly-documentation-lookup :which-key "Lookup on lispworks")
    "l" '(sly-load-file :which-key "Load file")
    "c" '(sly-compile-defun :which-key "Compile defun")
    "C" '(sly-compile-file :which-key "Compile file")
    "S" '(sly-mrepl-sync :which-key "Sync REPL"))
  (local-leader
    :keymaps 'lisp-mode-map
    :infix "e"
    "b" #'sly-eval-buffer
    "e" #'sly-eval-last-expression
    "f" #'sly-eval-defun
    "r" #'sly-eval-region)
  (nmap
    :keymaps 'sly-mrepl-mode-map
    "M-j" #'sly-mrepl-next-input-or-button
    "M-k" #'sly-mrepl-previous-input-or-button)
  (local-leader
    :keymaps 'sly-mrepl-mode-map
    "s" '(sly-mrepl-shortcut :which-key "Shortcut"))
  (nmap
    :keymaps 'sly-db-mode-map
    "\C-i" 'sly-db-cycle
    "g?" 'describe-mode
    "S" 'sly-db-show-frame-source
    "e" 'sly-db-eval-in-frame
    "d" 'sly-db-pprint-eval-in-frame
    "D" 'sly-db-disassemble
    "i" 'sly-db-inspect-in-frame
    "gj" 'sly-db-down
    "gk" 'sly-db-up
    (kbd "C-j") 'sly-db-down
    (kbd "C-k") 'sly-db-up
    "]]" 'sly-db-details-down
    "[[" 'sly-db-details-up
    (kbd "M-j") 'sly-db-details-down
    (kbd "M-k") 'sly-db-details-up
    "gg" 'sly-db-beginning-of-backtrace
    "G" 'sly-db-end-of-backtrace
    "t" 'sly-db-toggle-details
    "gr" 'sly-db-restart-frame
    "I" 'sly-db-invoke-restart-by-name
    "R" 'sly-db-return-from-frame
    "c" 'sly-db-continue
    "s" 'sly-db-step
    "n" 'sly-db-next
    "o" 'sly-db-out
    "b" 'sly-db-break-on-return
    "a" 'sly-db-abort
    "q" 'sly-db-quit
    "A" 'sly-db-break-with-system-debugger
    "B" 'sly-db-break-with-default-debugger
    "P" 'sly-db-print-condition
    "C" 'sly-db-inspect-condition
    "g:" 'sly-interactive-eval
    "0" 'sly-db-invoke-restart-0
    "1" 'sly-db-invoke-restart-1
    "2" 'sly-db-invoke-restart-2
    "3" 'sly-db-invoke-restart-3
    "4" 'sly-db-invoke-restart-4
    "5" 'sly-db-invoke-restart-5
    "6" 'sly-db-invoke-restart-6
    "7" 'sly-db-invoke-restart-7
    "8" 'sly-db-invoke-restart-8
    "9" 'sly-db-invoke-restart-9)
  (nmap
    :keymaps 'sly-inspector-mode-map
    "q" #'sly-inspector-quit))
#+end_src
*** Sly-ASDF
#+begin_src emacs-lisp
(use-package sly-asdf
  :straight t
  :after sly)
#+end_src
*** Emacs lisp
#+begin_src emacs-lisp
(use-package elisp-mode
  :defer t
  :pretty
  (lisp-mode-hook
   ("lambda" . "λ")
   ("nil"    . "Ø")
   ("and"    . "∧")
   ("or"     . "∨")
   ("<="     . "≤")
   (">="     . "≥")
   ("defun"  . "ƒ")
   ("loop"   . "Σ")
   ("mapcar" . "→")
   ("reduce" . "↓")
   ("some"   . "∃")
   ("every"  . "∀"))
  (emacs-lisp-mode-hook
   ("lambda" . "λ")
   ("nil"    . "Ø")
   ("and"    . "∧")
   ("or"     . "∨")
   ("defun"  . "ƒ")
   ("mapcar" . "→"))
  :general
  (:states '(normal motion visual)
   :keymaps '(emacs-lisp-mode-map lisp-mode-map lisp-interaction-mode-map)
   ")" #'sp-next-sexp
   "(" #'sp-previous-sexp)
  (nmmap
    :keymaps '(emacs-lisp-mode-map lisp-interaction-mode-map)
    "gr" #'eval-last-sexp)
  (vmap
    :keymaps '(emacs-lisp-mode-map lisp-interaction-mode-map)
    "gr" #'eval-region))
#+end_src
*** WIP Hydra like Lispy
:PROPERTIES:
:header-args:emacs-lisp: :tangle no
:END:
A [[*Hydra][Hydra]] which uses the ~Lispy~ package (by
abo-abo) to create a set of motions that allow movement around a lisp
file easily.

2024-04-18: Still working on this, quite rough around the edges.
#+begin_src emacs-lisp
(use-package lispy
  :after (lisp-mode elisp-mode)
  :hydra
  (hydra-lispy
   nil "Move around quickly in Lisp"
   ("h" #'lispy-left)
   ("j" ("t" #'lispy-teleport)
    #'lispy-down)
   ("k" #'lispy-up)
   ("l" #'lispy-right)
   ("d" #'lispy-different)
   ("u" #'lispy-flow)
   ("o" #'lispy-oneline)
   ("m" #'lispy-multiline)
   ("N" #'lispy-narrow)
   ("W" #'lispy-widen)
   ("c" #'lispy-clone)
   ("fp" #'lispy-ace-paren)
   ("fs" #'lispy-ace-symbol :exit t)
   ("H" #'lispy-slurp)
   ("L" #'lispy-barf)
   ("M-h" #'lispy-move-left)
   ("M-j" #'lispy-move-down)
   ("M-k" #'lispy-move-up)
   ("M-l" #'lispy-move-right)
   ("C-g" nil))
  :general
  (nmmap
    :keymaps '(emacs-lisp-mode-map lisp-mode-map)
    "." #'hydra-lispy/body))
#+end_src
*** Lisp indent function
Add a new lisp indent function which indents newline lists more
appropriately.
#+begin_src emacs-lisp
(use-package lisp-mode
  :defer t
  :config
  (defun +oreo/lisp-indent-function (indent-point state)
    (let ((normal-indent (current-column))
          (orig-point (point)))
      (goto-char (1+ (elt state 1)))
      (parse-partial-sexp (point) calculate-lisp-indent-last-sexp 0 t)
      (cond
       ;; car of form doesn't seem to be a symbol, or is a keyword
       ((and (elt state 2)
           (or (not (looking-at "\\sw\\|\\s_"))
              (looking-at ":")))
        (if (not (> (save-excursion (forward-line 1) (point))
                    calculate-lisp-indent-last-sexp))
            (progn (goto-char calculate-lisp-indent-last-sexp)
                   (beginning-of-line)
                   (parse-partial-sexp (point)
                                       calculate-lisp-indent-last-sexp 0 t)))
        ;; Indent under the list or under the first sexp on the same
        ;; line as calculate-lisp-indent-last-sexp.  Note that first
        ;; thing on that line has to be complete sexp since we are
        ;; inside the innermost containing sexp.
        (backward-prefix-chars)
        (current-column))
       ((and (save-excursion
             (goto-char indent-point)
             (skip-syntax-forward " ")
             (not (looking-at ":")))
           (save-excursion
             (goto-char orig-point)
             (looking-at ":")))
        (save-excursion
          (goto-char (+ 2 (elt state 1)))
          (current-column)))
       (t
        (let ((function (buffer-substring (point)
                                          (progn (forward-sexp 1) (point))))
              method)
          (setq method (or (function-get (intern-soft function)
                                        'lisp-indent-function)
                          (get (intern-soft function) 'lisp-indent-hook)))
          (cond ((or (eq method 'defun)
                    (and (null method)
                       (> (length function) 3)
                       (string-match "\\`def" function)))
                 (lisp-indent-defform state indent-point))
                ((integerp method)
                 (lisp-indent-specform method state
                                       indent-point normal-indent))
                (method
                 (funcall method indent-point state))))))))
  (setq-default lisp-indent-function #'+oreo/lisp-indent-function))
#+end_src