Writing Grex/Sed in Python, Perl, Emacs Lisp
also updated. Python: Find/Replace by Regex Text Pattern
for a Perl version: Perl: Find/Replace on Multiple Files
emacs lisp version: How to Write grep in Emacs Lisp
major update again. keyboard design. ErgoEmacs Keyboard
keyboard design. updated. ErgoEmacs Keyboard
for keyboard freaks. updated. Exotic Ergonomic Keyboards
some intermediate git tips, on its own page: git Frequently Asked Questions
How to set git output non-interactive?
there's no way. Just send it to a file then view that file.
git log > 888888
If you are using emacs, you can place cursor on the file path then call ffap (see: Emacs: Open File Path Under Cursor Fast), or install “magit” package for git. It's in MELPA repository. See
A Guide on Emacs 24 Package System.
How to make git display date in ISO format?
Use --date=iso.
git log --date=iso
See also: git Tutorial
Note: for those of you who know me, i got the keyboards free, but my opinion isn't bought, judge for yourself.
video. how i write blogs in emacs
lots pictures now. Computer Keyboards, Layouts, Hotkeys, Macros, RSI ⌨
Been using the Truly Ergonomic keyboard for 5 months now. Added my experience here at bottom: Truly Ergonomic Computer Keyboard Review.
updated. Python ＆ Perl: Traverse Directory
uploaded several of my file utils in perl to github. https://github.com/xahlee/xahscripts/tree/master/file_util
Perl: General Function for Sorting Matrix
wrote that in 1999, and used it in production back then. In 2006, i wrote a Python version but was incorrect. Going to write a Python version again.
Ruby, JavaScript, versions welcome.
there's a fantastic heart-shaped keyboard. If you haven't seen it already, see at Keyboard Porn to Infinity ⌨ ∞. The guy plans to manufacture it. To keep updated for news, watch his website at http://launch.keyboard.io/
the quality of a programing language, can be judged by how much of it can be explained by its syntax alone.
with this criterion, the order are roughly: Mathematica ≻ PHP ≻ Lisp ≻ JavaScript ≻ Ruby? ≻ Perl ≻ Python ≻ Java.
this is also the most important criterion in judging a language.
If you have coded one of {Haskell, ML/OCaml/F#, erlang, Scala, Pascal/Ada, Lua, tcl, APL, SmallTalk, PostScript}, i'd be interested in your opinion on their placement in the above. (you should have coded in the lang for a few years)
A new function key manufacture. See: http://www.access-is.com/custom_keyboards.php
that's nice if you are the master of function keys. See also:
thx to David Rogoff
inspired from emacs lisp doc. Logic Write Style: the Incongruousness of the Word “Actually”
to convert HTML to PDF on Linux, you can use wkhtmltopdf. It's based on webkit, the web browser engine used by Safari an Google Chrome.
# install sudo apt-get install wkhtmltopdf
wkhtmltopdf my_resume.html my_resume.pdf
if you just have one single file, you can also use libreoffice.
# install libreoffice sudo apt-get install libreoffice
Type libreoffice to start it, then, open the HTML file, then use menu 〖File ▸ Export…〗.
updated. Perl ＆ Python: Regex Example
on its own page. Tech Writing and Unix Humor
found a chinese site with tons of photos on KBC Poker keyboard. See links at: KBC Poker Keyboard, Ducky Keyboard (thx to cloudsben)
the Happy Hacking Keyboard, model “professional 2”, don't even have arrow keys. The Idiocy of Happy Hacking Keyboard
updated. Unicode Full-Width Characters
also updated. Python: Find/Replace by Regex Text Pattern
for a Perl version: Perl: Find/Replace on Multiple Files
emacs lisp version: How to Write grep in Emacs Lisp
also updated. Python: Find/Replace by Regex Text Pattern
want color diff?
sudo apt-get install colordiff
updated. discovered big chunck of code in emacs lisp using math symbols as function/variable names. Programing Style: Variable Naming: English Words Considered Harmful
why you need to swap middle/right mouse buttons, and how. Swap Mouse Buttons: Right-Click ＆ Middle-Click
Vote which one you want me to work on. Tell your friends please. http://pledgie.com/campaigns/19973
updated. Probably final form for a while. Linux Firewall Tutorial: iptables ＆ netfilter
more update. Some important problems of XML syntax. Refresh page. Nested Syntax Design: XML vs LISP
every now and then, people will ask what's the best keyboard for emacs. I thought i'll start a article dedicated to that. Best Keyboard for Emacs
updated. New photo. Kinesis Contoured Keyboard Review and RSI
excursion. 2 hands pen-spinning, by yours truely.
JavaScript in 3 hours. More massive update. Array manipulation, and others. JavaScript Basics by Example
discovered a keyboard tool, KeyTweak. See: Microsoft Windows: Keyboard Layout and Key Macro Tools
spent the whole day improving this JavaScript app for Unicode. Unicode: Arrow Symbols ← → ↑ ↓.
article hit hackernews. https://news.ycombinator.com/item?id=5184907 ◇ Why Python's Lambda is Broken and Can't be Fixed
updated. Keyboard Hardware Design Flaws
one of my article hit HackerNews. https://news.ycombinator.com/item?id=5517593
What Does it Means When a Programing Language Claims “Whitespace is Insignificant”?
updated. Unicode ASCII Art Collection
for unicode freaks. Allograph
updated. Unicode ASCII Art: Font Emulation
I have always wondered about this. You know that retrieving a indexed item of array takes O(1) time. Why is that? You have n things, and you want the kth item. It should be O(k) for kth item. It is impossible to get it with O(1).
The answer can't explained in software or algorithm. It really have to do with how the hardware is implemented. This article explains: 〔Why is Indexing Faster Than Binary Search By Yin Wang. @ yinwang0.wordpress.com…〕
updated, on its own page. Linux: Job Control Tutorial
cum, money. 19dfoa3Q7oehm9MwCULQzBG8vqfCaeMazH cum all you want on me. i swallow. #bitcoin
“when a man swallows, his destitution can be seen.” —Xah Lee
major revamp. Xah's CSS Tutorial
on its own page. IBM Model M keyboard, Unicomp
wow, Richard Stallman got into a quarrel with Linus on stage in FOSS'13 London and a riot started.
am very happy, that i've settled on this Unicode symbol ⁖ to represent “e.g.” or “example”. The name of that symbol in Unicode is THREE DOT PUNCTUATION. See bottom: Symbol, Semantics, Design: Unicode for “e.g.” (exempli gratia)
A nice essay: 〈Programming Languages Have Social Mores Not Idioms〉. Added the link to the bottom of Programing: Why Idiomatic Programing Are Bad.
on its own page. Python Libraries for Scientist
slight facelift. Xah's Java Tutorial
3 articles on the statet of the onion. Perl is not dead, but is dead end.
〔Texinfo 5.0 in Perl By Dave Cross. @ perlhacks.com…〕
〔Perl is not Dead, it is a Dead End By Stevan Little. @ speakerdeck.com…〕
〔Goodnight, Parrot By Chromatic. @ www.modernperlbooks.com…〕
Microsoft Sculpt Comfort Keyboard. Space bar is now split into a ⌫ Backspace key.
the keyboard from outer space.
more words added to the idiotic aspell. Go github at bottom to grab it. aspell's Dismal Vocabulary Size
hot from the oven. learn ngnix in 1 hour!
updated. Xah's Java Logo
added a photo of Commodore 64 keyboard. Keyboard: Control vs Capslock Position
MERCURY ☿ VENUS ♀ EARTH ♁ ⊕ MARS ♂ JUPITER ♃ SATURN ♄ URANUS ♅ ⛢ NEPTUNE ♆ PLUTO ♇. Added some interesting notes about these symbols, see bottom. Unicode Ancient Astronomy Symbols ☿ ♆ 🌛 ♋ (you might need to refresh the page)
new collection. documentation idiocy collection
facelifted. Python Documentation Problems
updated. How to Improve Python Doc; Notes on Rewriting Python Regex Doc
After 8 years, Python doc haven't improved much. There are complaints about Python doc about every year in Python mailing list, and Python doc wiki constantly crop up, but the python priests always flame and turn it down.
learned a new linux command. man lsmod. It shows the status of modules in the Linux Kernel. Basically pretty print 〔/proc/modules〕
sitewide replace all the Google Map and Google Earth icons.
the AIRPLANE was used for Google Map before because i couldn't find a better Unicode symbol. Same for Google Earth. The CIRCLED PLUS was a old astronomical symbol for Guia, mother earth. Unicode 6 now has better symbols, but i still can't find one that more properly represent map. Can you?
if you need fonts for Unicode 6, see Unicode 6 Emoticons and Supporting Fonts
here's a examples of pages that contain Google map/earth links:
eureka, i just found the name of my lang. laputa!
PS Gulliver's Travels. PART III. A VOYAGE TO LAPUTA, BALNIBARBI, LUGGNAGG, GLUBBDUBDRIB, AND JAPAN.
Xah Edict of the Day: anyone using the term REPL is to be despised upon immediately.
How should one call REPL then?
command-line user interface (CLUI)
Why should one call it CLUI?
Because, first of all, you are a idiot. That's what that I is for. And U don't have a clue. That's the CLU is for.
It's called CLUI because that's what it is.
REPL is like calling a car “gas combust crank run”. It's fashionable because you are a Tech Geeker and delights in jargon to hint your in-group status.
read more at REPL Jargon
on its own page. USB3 Drive Speed
updated on how to fix. Fix Defective Keys in Comfort Curve Keyboard
much more info about the OMeta lang at bottom: Proliferation of Computing Languages
started to work on Linux iptables tutorial. Linux: iptables Basics
another keyboard layout. qwpr Keyboard Layout. Also, the Workman layout has a much improved home page, with a active forum. See bottom: Computer Keyboard Layouts: Dvorak vs Colemak vs Workman
lol. perl added a say in v5.10 . It's like print but adds newline at the end. But you have to use v5.10; first. Quote from perldoc -f say.
say FILEHANDLE LIST
say FILEHANDLE
say LIST
say Just like "print", but implicitly appends a newline. "say LIST"
is simply an abbreviation for "{ local $\ = "\n"; print LIST }".
To use FILEHANDLE without a LIST to print the contents of $_ to
it, you must use a real filehandle like "FH", not an indirect
one like $fh.
This keyword is available only when the "say" feature is
enabled; see feature. Alternately, include a "use v5.10" or
later to the current scope.
these days, perl monger remnants try to revive perl from death bed, and talk about “modern perl”. LOL. the very name is funny. Am guessing the next step would be post-modern perl? or is that already a trope?
learned a new Linux command: watch. ⁖ watch netstat.
this is useful when you want to run some command regularly and itself doesn't have auto-update.
thx to Ryuutei Sebastien BLANC
I don't know much about Operating System. I was just wondering whether or why the networking component is part of the kernel. Then, found this fantastic map. Linux Kernel Map.
learning notes. Linux: What's Netfilter, iptables, Their Differences?
Linux networking. iptables man page.
ACCEPT means to let the packet through. DROP means to drop the packet on the floor.
Note that we drop it to the floor, not, river or lake, as Microsoft might.
Xah's Edu Corner of the Day
there are 2 types of firewalls. Complicated and Uncomplicated. Linux supports the uncomplicated type, called ufw. It stands for Uncomplicated Fire Wall. Type man ufw in terminal to read its doc.
the complicated type is related to the math concept of complex number.
PS this post is of import due to its affinity to the field of linguistics, category theory, the theory of archetype, and ontology.
added a video review of the mech4 mechanical keyboard. Real high quality keyboard. Gaming Keyboards: Levetron, BlackWidow, Sidewinder. Also added them is the BlackWidow from Razer.
added domino tiles, mahjong tiles. Sports ＆ Games Icons ⚽ ⛷ 🏁 🂡 ♞
recently discovered proper symbol for the Alt key, and few others. Example:
charmap, there's a note that this symbol can be used to mean “control”. (haven't found out what's the source of the note. Might be from ISO standard. Anyone knows?)btw, when you plugin a Mac keyboard into PC, or PC keyboard into Mac, you'll notice that Mac's ⌥ Opt = PC's Alt, and likewise for ⌘ Cmd and ❖ Win. I always wondered if the keys send the same signal or perhaps it's the OS that's doing the remapping. Answer: The keys send the same signal. So, this means the keys are just difference in key label, and the physical positions are swapped.
you can see all these here Unicode: Keyboard Symbols, UI Icons ↹ ⌫ ⌘ ✉ ✍ ⌖
heard a new language OMeta. Home page at http://tinlizzie.org/ometa/
from a comment at Pattern Matching vs Lexical Grammar Specification
now complete. Unicode Music Symbols 𝄞 ♩ ♪ ♫ ♬ 🎸 🎹 🎻 🎷
playing cards in Unicode. Sports ＆ Games Icons ⚽ ⛷ 🏁 🂡 ♞
learned a new linux command tree. It prints a dir in a visual tree format, similar to pstree. You have to install: sudo apt-get install tree. See also Linux: Most Frequently Used Shell Commands.
learned today that Apple's color font, is actually color font technology, not secondary step of replacing fonts by images. See screenshots here: Unicode Icons: Food, Drink
Unicode is such a beast. Y'know, it encompasses all written languages, including ancient dead ones. But that's not all. When you dig into Unicode symbols, you see the thousands of math symbols, printer's symbols, forgotten punctuations, ancient astronomy symbols…, some of which we use today but don't have any clue of their origin. ⁖ ☤ ☧ 卐 ☥ ☯ ⚸ ….
See, for example: Unicode: Dingbats, Cultural Symbols
you might be curious, and started to read about what they are for. I started that way some 5 years ago. First due to my love with math symbols. After few years doing it casually, you realize, to really understand all the symbols, their origin, history, can take you few years to decades. Not even counting the alphabets of dead writing systems.
unicode 6 added over 2k chars. 600 of them are emoticons, and many others are pictographs. Unicode 6 came out in 2010, but there's still not that many fonts supporting all those pictogram. On Mac, it's most beautifully done. See screenshots at bottom of Unicode Icons: Food, Drink. On Window, Microsoft came up with Segoe UI Symbol-12, in 2012, as part of Window update. On linux, nada, but you can download the free font Symbola, which is very high quality. See bottom here: Unicode 6 Emoticons and Supporting Fonts.
to install font on Ubuntu, just unzip it, and double click it should do.
all i ever needed to know about keyboard, i didn't learn in kindergarten. Three hundred fourty images of keyboards. Keyboard Image Index
wrote a JavaScript app. Goto Unicode Emoticons, Faces 😸, hover your mouse over (or click if you are on tablet). Unicode name and char number will show.
also created the following pages.
python tip. To get image dimension (width and height in pixels), you can do:
# -*- coding: utf-8 -*- # Python import Image print Image.open("/home/xah/pictures/cat.jpg").size
but for python 3, the image library isn't there yet.
about a month ago, i decided to replace all use of “e.g.” on my site to the Unicode “ℯℊ”. Symbol, Semantics, Design: Unicode for “e.g.” (exempli gratia)
But now, it's like The Tell-Tale Heart, i confess, i can no longer tolerate my incorrect use of symbols. The scripted e ℯ is usually used for Euler's number in math. The scripted g ℊ has no popular designated meaning. They in no way means “exempli gratia”. So, now i decided to replace them all to the more symbolic ⥱.
My writing's already filled with willful eyesore to the establishment. (☛ The Writing Style of Xah Lee) What's with just one more symbolic idiosyncrazy?
but i take console that i'm in the same class as Stanislaw Szukalski, Robert Crumb, Jonathan Swift, Friedrich Nietzsche, Leo Tolstoy. No doubt.
Kinesis has a new generation of their split keyboard, Freestyle 2. See: 2-Piece Split Keyboards
Ruby's predefined global variables is not documented, but Ruby 2.0, which came out few days ago, fixed that. Ruby: List of Predefined Global Variables