gists/gists.org

#+title: Gists by bram85
#+PROPERTY: header-args :mkdirp yes

#+begin_src org :tangle README.org
  Gists referred from [[https://emacs.ch/@bram85][@bram85@emacs.ch]].

  Unfortunately gitea has no gist support and there's no mature yet lightweight gist solution suitable for self-hosting, so resorting to this poor-man's setup of sharing gists with an audience.
#+end_src

* Termux keys :termux:emacs:
:PROPERTIES:
:URL:      https://emacs.ch/@bram85/109393570150138285
:END:

Put this in ~/.termux/termux.properties for a better Emacs experience inside Termux.

#+begin_src conf :tangle gists/termux-emacs-keys.conf
  extra-keys = [[ \
    {key: ESC, popup: {macro: "CTRL g", display: "C-g"}}, \
    {key: CTRL, popup: {macro: "CTRL x", display: "C-x"}}, \
    {key: ALT, popup: {macro: "ALT x", display: "M-x"}}, \
    {key: TAB}, \
    {key: DEL, popup: {macro: "CTRL k", display: C-k}}, \
    {key: LEFT, popup: HOME}, \
    {key: DOWN, popup: PGDN}, \
    {key: UP, popup: PGUP}, \
    {key: RIGHT, popup: END} \
  ]]
#+end_src

* Nesting with use-package :emacs:usepackage:
:PROPERTIES:
:URL:      https://emacs.ch/@bram85/109393551314878399
:END:

#+begin_src elisp :tangle gists/use-package-nesting.el
  ;; Demonstrate that use-package allows for nesting configurations,
  ;; although it is done semantically rather than syntactically. The
  ;; :after keyword makes sure that the 'bar' package is only evaluated
  ;; after the 'foo' package was loaded.

  (use-package foo)

  ;; only loads after foo has been loaded
  (use-package bar
    :after foo)
#+end_src

* Track usage of Emacs packages over time :emacs:org:orgbabel:
:PROPERTIES:
:URL:      https://emacs.ch/@bram85/109403483724552863
:END:

Using the idea of evaluating code on state changes [[id:3be8333e-7a47-4251-8ee4-2cba0ec4614b][below]].

#+begin_src org :tangle gists/track-use-package-over-time.org
  ,* TODO Update Emacs package count
  DEADLINE: <2023-01-04 Wed .+1m>
  :PROPERTIES:
  :LAST_REPEAT: [2022-12-04 Sun 10:56]
  :ON_DONE: (org-babel-execute-subtree)
  :END:
  :LOGBOOK:
  - State "DONE"       from "TODO"       [2022-11-26 Sat 07:57]
  :END:

  A small org file to keep track of some metric in a table, see [[https://orgmode.org/manual/Results-of-Evaluation.html][Results of Evaluation]] in the Org mode manual for more information. It's important that the function is supposed to return a list in order to record the result as a table row.

  In this case, count the number of packages in my Emacs init file. It is executed automatically when the task is marked as done, using [[https://apps.bram85.nl/gitea/bram/gists/src/branch/main/gists/evaluate-code-on-task-state-change.org][this function]].

  Press =C-c C-c= inside the code block to add a new entry to the table below.

  ,#+begin_src elisp :results table append
    (with-temp-buffer
      (insert-file-contents user-init-file)
      (list (format-time-string "%F")
            (count-matches (rx (seq "(" (? "elpaca-") "use-package" space)))))
  ,#+end_src

  ,#+RESULTS:
  | 2022-11-25 | 140 |
  | 2022-11-26 | 140 |
#+end_src

* vertico-repeat setup :emacs:vertico:
:PROPERTIES:
:URL:      https://emacs.ch/@bram85/109408577100294769
:END:

My vertico-repeat setup.

#+begin_src elisp :tangle gists/vertico-repeat.el
  (use-package vertico-repeat
    :straight (vertico-repeat :host github :repo "emacs-straight/vertico" :files ("extensions/vertico-repeat.el"))
    :after (vertico savehist)
    :bind
    ("M-g r" . vertico-repeat-select)
    :config
    (add-to-list 'savehist-additional-variables 'vertico-repeat-history)
    :hook
    (minibuffer-setup . vertico-repeat-save))
#+end_src

* Evaluate code on task state changes :emacs:org:
:PROPERTIES:
:ID:       3be8333e-7a47-4251-8ee4-2cba0ec4614b
:END:

#+begin_src org :tangle gists/evaluate-code-on-task-state-change.org
  The function below evaluates Lisp forms stored in properties of a task, when it changes to a certain state. The function is supposed to be added to the =org-after-todo-state-change-hook=.

  The property should be named =ON_<STATE>= where =STATE= is a state defined in =org-todo-keywords=. See also the example task below (open this file in [[https://apps.bram85.nl/gitea/bram/gists/raw/branch/main/gists/evaluate-code-on-task-state-change.org][raw mode]] to see the properties).

  ,#+begin_src elisp
    (defun my/task-state-event-handler ()
      "Evaluate a Lisp form attached to the task whose state is being changed.

    When this function is added to org-after-todo-state-change-hook,
    it looks for a Lisp form stored in the property called ON_<STATE>
    where STATE is the new state of the todo item. When the state is
    cleared, ON_CLEAR will be used.

    Example:

    ,,* TODO Example task
    :PROPERTIES:
    :ON_PROGRESS: (message \"Busy!\")
    :ON_DONE:     (message \"Done!\")
    :ON_CLEAR:    (message \"No state.\")
    :END:"

      (when-let* ((state (or org-state "CLEAR"))
                  (event-property-name (concat "ON_" state))
                  (code-string (cdr (assoc event-property-name
                                           (org-entry-properties))))
                  (code (car (read-from-string code-string))))
        (org-eval code)))

    (add-hook 'org-after-todo-state-change-hook 'my/task-state-event-handler)
  ,#+end_src

  ,* TODO Example task
  :PROPERTIES:
  :ON_PROGRESS: (message "Busy!")
  :ON_DONE:     (message "Done!")
  :ON_CLEAR:    (message "No state.")
  :END:
#+end_src

* Emacs commenting: do what I actually mean :emacs:

#+begin_src elisp :tangle gists/emacs-comments-do-what-i-actually-mean.el
  ;; Replace comment-dwim (M-;) with a modified version of
  ;; comment-or-uncomment-region. The modification is done by the crux
  ;; [1] package, which acts on a region if active otherwise on the
  ;; current line.
  ;;
  ;; My personal preference goes to using straight.el-powered
  ;; use-package forms, even for built-in modules.
  ;;
  ;; [1] https://github.com/bbatsov/crux

  (use-package newcomment
    :straight (:type built-in)
    :bind
    ([remap comment-dwim] . #'comment-or-uncomment-region))

  (use-package crux
    :config
    (crux-with-region-or-line comment-or-uncomment-region))
#+end_src

* Use xr for more readable regular expressions :emacs:

#+begin_src org :tangle gists/xr-for-readable-regular-expressions.org
  If you look for the value of =org-link-any-re=, you'll see this beauty:

  ,#+begin_example
  "\\(\\[\\[\\(\\(?:[^][\\]\\|\\\\\\(?:\\\\\\\\\\)*[][]\\|\\\\+[^][]\\)+\\)]\\(?:\\[\\([^z-a]+?\\)]\\)?]\\)\\|\\(<\\(bibtex\\|elisp\\|f\\(?:ile\\(?:\\+\\(?:\\(?:emac\\|sy\\)s\\)\\)?\\|tp\\)\\|h\\(?:elp\\|ttps?\\)\\|id\\|mai\\(?:lto\\|rix\\)\\|news\\|org-ql-search\\|shell\\):\\([^>
  ]*\\(?:
  [ 	]*[^>
  ][^>
  ]*\\)*\\)>\\)\\|\\(\\(?:\\<\\(?:\\(bibtex\\|elisp\\|f\\(?:ile\\(?:\\+\\(?:\\(?:emac\\|sy\\)s\\)\\)?\\|tp\\)\\|h\\(?:elp\\|ttps?\\)\\|id\\|mai\\(?:lto\\|rix\\)\\|news\\|org-ql-search\\|shell\\)\\):\\(\\(?:[^][
  ()<>]\\|(\\(?:[^][
  ()<>]\\|([^][
  ()<>]*)\\)*)\\)+\\(?:[^[:punct:]
  ]\\|/\\|(\\(?:[^][
  ()<>]\\|([^][
  ()<>]*)\\)*)\\)\\)\\)\\)"
  ,#+end_example

  [[https://github.com/mattiase/xr][xr]] to the rescue:

  ,#+begin_src elisp
    (pp-to-string (xr org-link-any-re))
  ,#+end_src

  ,#+RESULTS:
  ,#+begin_example
  (or
   (group "[["
          (group
           (one-or-more
            (or
             (not
              (any "[\\]"))
             (seq "\\"
                  (zero-or-more "\\\\")
                  (any "[]"))
             (seq
              (one-or-more "\\")
              (not
               (any "[]"))))))
          "]"
          (opt "["
               (group
                (+\? anything))
               "]")
          "]")
   (group "<"
          (group
           (or "bibtex" "elisp"
               (seq "f"
                    (or
                     (seq "ile"
                          (opt "+"
                               (or "emac" "sy")
                               "s"))
                     "tp"))
               (seq "h"
                    (or "elp"
                        (seq "ttp"
                             (opt "s"))))
               "id"
               (seq "mai"
                    (or "lto" "rix"))
               "news" "org-ql-search" "shell"))
          ":"
          (group
           (zero-or-more
            (not
             (any "\n>")))
           (zero-or-more "\n"
                         (zero-or-more
                          (any "	 "))
                         (not
                          (any "	\n >"))
                         (zero-or-more
                          (not
                           (any "\n>")))))
          ">")
   (group bow
          (group
           (or "bibtex" "elisp"
               (seq "f"
                    (or
                     (seq "ile"
                          (opt "+"
                               (or "emac" "sy")
                               "s"))
                     "tp"))
               (seq "h"
                    (or "elp"
                        (seq "ttp"
                             (opt "s"))))
               "id"
               (seq "mai"
                    (or "lto" "rix"))
               "news" "org-ql-search" "shell"))
          ":"
          (group
           (one-or-more
            (or
             (not
              (any "	\n ()<>[]"))
             (seq "("
                  (zero-or-more
                   (or
                    (not
                     (any "	\n ()<>[]"))
                    (seq "("
                         (zero-or-more
                          (not
                           (any "	\n ()<>[]")))
                         ")")))
                  ")")))
           (or
            (not
             (any "	\n " punct))
            "/"
            (seq "("
                 (zero-or-more
                  (or
                   (not
                    (any "	\n ()<>[]"))
                   (seq "("
                        (zero-or-more
                         (not
                          (any "	\n ()<>[]")))
                        ")")))
                 ")")))))
  ,#+end_example
* Define a lambda in a let expression

#+begin_src elisp :tangle gists/let-lambda.el
  (let ((f (lambda (s) (message s))))
    ;; f is a variable so should be treated as such.
    (funcall f "This works.")

    ;; f is not a function so cannot be found if called like this.
    (f "This does not work."))
#+end_src

* Meta
** License

#+begin_src org :tangle LICENSE.txt
MIT License

Copyright (c) 2022 Bram Schoenmakers

Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
in the Software without restriction, including without limitation the rights
to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the Software is
furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all
copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
SOFTWARE.
#+end_src

** COMMENT Local variables

Auto tangle this file on save.

Local variables:
eval: (add-hook 'after-save-hook #'org-babel-tangle 0 t)
End: