Xah Emacs Blog Archive 2017-01

Emacs: Interactive Abbrev (moved url)

get a practical understanding. Public-Key Cryptography Concepts for Programers

The X-Windows Disaster This rant that every unix user knows in 1990s. Not so much in 2000s. Forgotten today.

learn how to use GNU GPG in 10 minutes. GPG Tutorial

Emacs: Abbrev Mode

The above is rewritten, reverting to my old method of using abbrev by using a elisp abbrev file. It is the most simple and efficient way of using emacs abbrev.

Here's the traditional way of using emacs command, see:

Emacs: Abbrev Mode Tutorial

It's much more complex. After using the traditional way for half a year, i reverted to the elisp file way.

Emacs: git, magit-mode (updated)

Customize Emacs

following are reviewed and updated (all minor).

1. Emacs: Init File Tutorial
2. Emacs: How to Install Packages Using ELPA, MELPA
3. How to Install Emacs Package Manually
4. Emacs: How to Define Keys
5. Emacs: M-x customize Tutorial
6. Emacs: Set File to Open in a Major Mode
7. Emacs: Organize Init File
8. Emacs: Byte Compile Elisp Files
9. Emacs: What's Hook?
10. Emacs: Set Environment Variables within Emacs

i get a lot flames for this over the years.

see Emacs: Why You Should Not Swap CapsLock and Control

Emacs Chinese Input (minor update)

Emacs: Copy/Cut Current Line If No Selection

code update. now xah-copy-line-or-region won't move cursor to next line if region is active.

Thanks to baron42bba, from https://github.com/baron42bba/.emacs.d/commit/d96ce7e671628bb0f7b5307734a7e6f25295e602

JavaScript is the Number 1 Programing Language

Emacs: Xah JavaScript Mode

worked much on this in past year. Still 2 things need to be done. Indentation, and coloring of js regex string. But otherwise, it's got best completion, best function template, and best syntax coloring.

by the way, js is the most popular language for a number of years now. See http://redmonk.com/sogrady/2017/03/17/language-rankings-1-17/ and reddit discussion

also, learn from my tutorial.

[see JavaScript in Depth]

Been working on that in past 6 months, adding ES2015 features, and transforming it into a complete reference. That is, detailed page of ALL JavaScript objects and methods.

see JavaScript Object Reference

[see JavaScript: ECMAScript 2015 Features]

i'm surviving on $500 a month for past few years.

Buy Xah Emacs Tutorial

and

Buy Xah JavaScript Tutorial

much appreciated. Thanks.

Xah Emacs Commands New index.

Emacs: Delete Brackets ()[]{} by Pair (code update. Now if C-u is pressed first, don't delete inner text. See docstring for detail.)

Kinesis Edge keyboard

If you like traditional shaped keyboard, a top-notch one is coming out. Kinesis Edge keyboard. I consider it better than all traditional shaped existing keyboards. If you buy now, you save about $80.

see https://www.kickstarter.com/projects/294674098/freestyle-edge-the-ultimate-split-gaming-keyboard

Also, subscribe my keyboard blog at Xah keyboard Blog

If you are on linux, check out Xah's Linux Setup. lots tips and tutorials.

also, follow my programing blog. Xah Programing Blog

Emacs: xah-get-thing.el (major rewrite)

Emacs: Lines to HTML Table (complete rewrite)

Emacs: Change Brackets () {} [] in Region code update, and emacs repeat-complex-command problem

Emacs: Change Brackets/Quotes (code update.)

fixed the pesky problem of emacs repeat-complex-command problem of not getting the correct region begin/end.

here's quick explanation.

In emacs, after you've done an interactive command call involving prompting, you can call the command again by Alt+x repeat-complex-command, without needing to answer the prompts.

[see Emacs: Repeat Last Prompted Command]

The problem is, if your write your elisp code using interactive with region begin/end as arguments, like this

(defun my-do-line-or-region (begin end)
  "do x, on current line or active region."
  (interactive
   (if (use-region-p)
       (list (region-beginning) (region-end))
     (list (line-beginning-position) (line-end-position))))
  (message "%s %s" begin end))

then, when your call repeat-complex-command, the region positions are hard-coded from last call.

there are solutions but i haven't found them to be robust. don't have time to write a detailed account now.

basically, more reliable is simply remove the begin/end as parameters. The problem with this is that now the command is less convenient to use in elisp code. Before, you can call the function with begin/end positions. This is clear code. Now, you have to mark a region first and make it active. This is less clear code.

Emacs: Novel Reading Mode (updated)

Emacs new version xah-lookup.el, added xah-lookup-etymology Emacs: xah-lookup.el, Lookup the Web

Best Tool for Yak Shaving: Emacs

Xah Emacs Tutorial, new version out

Buy Xah Emacs Tutorial

huge amount of update in the past 3 months. Lots new super efficient commands, tutorial on syntax table, new JavaScript engine of doc popup in browser, and xah-fly-keys now supports qwerty, a major milestone.

Recommend to a friend. Link to articles. Buy it. Thanks.

sending out update to previous buyers this week.

Emacs: Make Whitespaces Visible (major rewrite)

Elisp: Syntax Table Tutorial (new)

Emacs: Delete Brackets ()[]{} by Pair (updated code. Now works on «»‹›“” too.)

Elisp: How to Find Syntax of a Character?

Elisp: How to Modify Syntax Table Temporarily (rewritten)

xah-fly-keys, announced on reddit. https://www.reddit.com/r/emacs/comments/5t884r/xah_fly_keys_now_supports_qwerty_layout/

If you support the project, please give it a upvote, and tell friends. Thanks.

also, star it on github. https://github.com/xahlee/xah-fly-keys Thanks.

home page at Emacs: Xah Fly Keys

Emacs: Run Current File (updated. Now supports TypeScript)

Emacs: xah-lookup.el, Lookup the Web

Major new version. Now you can customize each lookup command's URL and which browser to use. Can also write your own command to lookup php, clojure, etc. New version should be in MELPA the next day.

xah-fly-keys with Truly Ergonomic Keyboard. Major update. New layout design.

for Kinesis users, see Kinesis/Ergodox layout for xah-fly-keys

How to Make the CapsLock Key do Home Key (updated, for Linux, Mac, Microsoft Windows)

Emacs: Working with CSS Color Values (updated code. calls font-lock-flush instead of font-lock-fontify-buffer)

big thanks to Avi for donation $$$ for Emacs: Xah Fly Keys

open this file in emacs. https://tc39.github.io/ecma262/2016/#. 13th line is 1.2M chars. emacs death.

solution: Alt+x fundamental-mode.

Emacs: Xah Fly Keys (now it overrides other minor modes, as it should.)

Emacs: xah-find.el, Find Replace in Pure Elisp (now you can customize face. Alt+x customize-group, then type xah-find.)

reddit discussion, on emacs naming convention

https://www.reddit.com/r/emacs/comments/5pcvmt/when_naming_an_emacs_function_why_is_the_package/

it's the convention of the mothership.

many of these conventions, are kinda vague, some are out-dated, some are ill-designed.

many packages outside GNU emacs do not adhere to them, but are tolerated. For example, the most popular packages on MELPA, dash, s, break these conventions.

it's a gray area, between conservative and progressive.

if you chose progressive, the problem is that huge amounts of existing lisp code are not gonna change (lots work, risking bug to fix but little benefit, or packages not maintained but still used, etc.), you end up with inconsistency.

if you chose conservative, then you reduce progress and adoptation.

For example, let's say the naming convention. Besides the prefix:

• predicate could end in ? (as in Scheme/Racket Lisp, ruby, clojure) instead of p. Since question mark is more intuitive, is easier to identify, and can be syntactically verified by machine. (p can't because not all functions ending in p is a predicate.)

• the double dash for internal methods (aka auxiliary functions) is kinda unsaid convention, and code out there may or may not conform. (if we go strict about this, i think one'll find huge amount of functions need to be renamed.)

• variable beginning with low line _ as form-filler unused var is another unsaid convention. It kinda came from modern (say after 2010) practices in other langs (i think python ruby).

• in function doc string, it's GNU emacs convention to use ALLCAPS for parameters. This is also not a perfect convention, since elisp is case sensitive. This make it hard to actually have parameters that's ALLCAP or camelCase or single capital letter such as Z. Also, using ALLCAPS is a weak, ambiguous markup, since it prevents the normal English convention of using ALLCAPS for emphasis.

but as most coding convention goes, they are not systematically designed. They came by-and-by via practice and evolution. It'd be nice if the language enforce syntactic conventions. For example, var of ALLCAPS has semantics of global var. (sigils in perl, ruby, golang, and other lang feature these) An extreme case would be syntax algebra, where the syntax alone is the semantics and can be processed/manipulated (like highschool algebra). Formal Languages are such case.

• The Sigils WAR, Language Design and Coding Convention
• Docstring Convention: Python vs Emacs Lisp
• Sigil for Function Parameter Names

Emacs: Xah Fly Keys now supports QWERTY layout! Try it.

Emacs lots work on Xah Fly Keys in past month. Added 5 efficient commands. Emacs: Xah Fly Keys

Emacs: 1 Key to Copy/Paste from Register

new command xah-append-to-register-1 and xah-clear-register-1

emacs poll: do you ever use point-to-register and jump-to-register?

vote at https://twitter.com/ErgoEmacs/status/821882792183099393

Emacs: Move Cursor to Beginning of Line/Paragraph code complete rewrite. Now does not depend on another function.

Emacs: Upcase Sentences (new command)

Emacs: Delete Brackets ()[]{} by Pair (now supports ascii quotes.)

all syntax coloring on the site are redone, based on the latest version of Emacs: Xah Emacs Lisp Mode (that is, if you use xah-elisp-mode, the coloring in emacs buffer would be the same as on the website.)

notable is that the coloring are based on the “types” of symbol, as detailed here: Meaning of Lisp List, Function Type, and Syntax Coloring

still to do, is the tooltips for variables.

Emacs: Paste or Paste Previous (bug fix)

Meaning of Lisp List, Function Type, and Syntax Coloring

poll: 'NOERROR vs "NOERROR"

new poll, 'NOERROR vs "NOERROR". vote at

• https://plus.google.com/113859563190964307534/posts/MgSBLBzaYQS?sfc=true
• https://twitter.com/ErgoEmacs/status/819283352041570304

Elisp: Symbol vs String for non-nil Values

Elisp: Find Matching Bracket Character (new article)

Emacs: Quote Lines (code update. Now delimiters are added by skipping whitespaces)

Programing Language: Syntactic and Semantic Difference of Map Function

How Many Keyboard Shortcuts Are There

new tooltips

the tooltips are regenerated, from emacs 25.1

now ALL functions mentioned in elisp manual have tooltips. try (info "(elisp) Point") and Elisp: What's Function. (goto the page, hover mouse over a function name, or touch it in phone/tablet.)

though, it turns out, quite a lot commonly used functions are not in elisp manual. For example, eval-last-sexp, ielm, describe-function.

Am working on that. Also, variable will also have tooltip soon.

Elisp: What's Function (major rewrite.)

i think sometime between 2013 to 2016, defun is moved from implemented in C to implemented in elisp.

;; test if defun is implemented in C
(subrp (symbol-function 'defun))

#emacs ido-completing-read can handle 81k items no problem

Emacs: Delete Brackets ()[]{} by Pair (new command.)

Emacs: Paste or Paste Previous (new command)

Emacs: Xah Emacs Lisp Mode (Major update. Now, ALL elisp symbols in elisp manual are colored, and are colored by their technical type: function, special form, macro, command, user option, variable. )

Emacs: Change to Title Case (minor code update. fixed “can'T” to “can't”)

List of Emacs Starter Kits

new one is scimax, for scientist/engineer for reproducible research and publishing. Focus on LaTeX and org-mode.

Emacs: View Info Page (minor update; new screenshot)