Xah Programing Blog Archive 2016-08
[The piracy paradox at Udemy By Troy Hunt. At https://www.troyhunt.com/the-piracy-paradox-at-udemy/ , Accessed on 2016-08-28 ]
- udemy is a online learning platform. It lets people upload courses, and learner buy them.
- But udemy has a piracy problem.
- That is, you write a tutorial for something, and people steal it and sell it on udemy.
- And this seems to be happening a lot.
- udemy is likened to youtube, that itself doesn't filter or check for quality.
hackers in the 1990s, are interested in literature, linguistics, nerd as walking encyclopedia. Today, i don't seem to see much.
Today's coder gone illiterate? or, perhaps social media and too much info made the real nerd hard to find?
selected collection of lisp essays.
Revamped index. Collected criticism of computer lang docs.
Xah Python Tutorial Accolade
MiniKanren relational language, name origin
MiniKanren relational language. The name “kan ren” came from Japanese 関连, which is Chinese, meaning “relations”. lol
html navigation panel implementation redone
redone navigation panel for all my sites.
2601 files changed.
and the following files created
The change shouldn't be visible to user. It's the implementation that changed, for the side panel.
For those curious, here's the deal.
before, each page contains the whole static html side panel. That is, a list of links is duplicated in every file. The problem is, if you want to change the navigation bar, you have to change every file. You also have to make sure that every file's text is exactly the same. And, if one file happens to have a extra space, that causes problem in your find/replace script when you change the side panel.
now, the new implementation, the nav panel is a file by itself, and is embedded in each page as iframe.
The disadvantage using iframe is that each page now needs to make an extra http request. (but it's cached, good if the nav panel contains several images)
on the whole, i think with iframe is much better. The iframe solves a major issue about navigation panel i had, that is, it's not possible to keep the side panel code identical when articles are in different directories. (and the consequence of that is you cannot use find/replace anymore when you want to change side panel.)
here's a sampling, hope it's interesting.
- Python Doc Problem Example: sort()
- Idiocy of Computer Language Docs: Unix, Python, Perl, Haskell
- Once upon a troll…
- Paul Graham's Infatuation with the Concept of Hacker
- The Jargon Automata in Finite State Automata
- On the Question of Too Many Programing Libraries
- OOP's Jargons and Complexities
- Netiquette Anthropology: Tales of Tech Geekers
- Clojure Instaparse Parser Tutorial
- Curves and Their Properties: Catenary, p012
- How Compiler Works
after Shakespeare [see The Tragedy Of Titus Andronicus by Shakespeare] , Sir Richard Burton's arabian nights is the most fascinating literature and style i've read.
here's a story of The Arabian Nights, where girls fight to suck… The Arabian Nights: 70. ABU AL-ASWAD AND HIS SLAVE-GIRL
and this is the most wondrous scifi. finish in couple hrs, understand 4th dimension.
best short scifi. FLATLAND: A Romance of Many Dimensions
can finish in few hours. You'll understand 4th dimension. It's also a social philosophy, mock history, and a tragedy.
Weird Unicode Math Symbol: DIFFERENCE BETWEEN
- name: DIFFERENCE BETWEEN
- codepoint 8783, x224f
unicode symbol becomes pictograph, a problem
wow, unicode “U+FE0E: VARIATION SELECTOR-15”. Add that char after another char to select the variation you want.
Microsoft release PowerShell on Linux and Open Source!
[PowerShell on Linux and Open Source! By Microsoft. At https://blogs.msdn.microsoft.com/powershell/2016/08/18/powershell-on-linux-and-open-source-2/ , Accessed on 2016-08-19 ]
for a quick tutorial, see PowerShell Tutorial
pure speculation, but i suspect, any math proof related work/software traditionally done with #ocaml or #haskell can be done with golang easily.
in other words, i don't think there's any critical or foundational stuff in OCaml related to theorem proving.
[Category Theory for the Working Hacker By Philip Wadler. At https://www.infoq.com/presentations/category-theory-propositions-principle?utm_source=twitter&utm_medium=link&utm_campaign=calendar , Accessed on 2016-08-19 ]
why random number is critical in encryption?
yesterday i had a question answered that puzzled me for years. thanks to @johnkitchin @bren_fdez
Q: why random number is critical in encryption?
A: because symmetric cypher is used for payload, and the key is a random number.
understand Public-key Cryptography in 5 minutes Understanding Public-Key Cryptography for Beginner
learn Julia in y minutes. https://learnxinyminutes.com/docs/julia/
functional programers and Golang
i've heard a few functional programers in my circle criticize golang. I think it's more like “it's not my clan” type of thing
i've also heard a few functional programers in my circle loving rustlang. I think it's “i don't want golang to win cuz its from skynet”
golang is fantastic. It's spec The Go Programming Language Specification - The Go Programming Language is shorter than Scheme Lisp now.
the best golang tutorial is https://gobyexample.com/ by @mmcgrana , simple, concrete, by example, no more.
line diff and semantic diff
recently there's idea of semantic diff. not line diff. Note that, line diff originates from unix brain damage of line truncation.
actually, the very concept of diff should be ban'd, line or semantic. Am not sure the detail, but a haunch
ocaml haskell are not math language, julia is
am beginning to see, ocaml haskell isn't my thing. like C, they are still computer engineer's by-product, not mathematician's thing.
i want a lang that's Wolfram Language in design principle but efficient. A mathematician's lang. I think, Julia is my hope.
what's this math lang i speak of? it's a lang where concepts of computer engineering by-product does not surface in the lang. if so, it's explicit.
are there such lang? yes. APL, Matlab, Wolfram Language, Julia.
whatever relation of ocaml haskell has with math, is only a historical happenstance. As lisp is.
the major concepts of comp engineering by-product are: int float double long reference pointer. They should be ban'd.
one of the most garish by-product of computer engineering in languages is: main()!
you can judge if a computer language is stupid by whether it has the “main”. Surprise of surprise, haskell has it! no wonder.
Do KNOW, that the origin of ocaml is ML, which is from 1973. Ancient. haskell's concepts and demeanors, belongs to the same lineage.
see also Is Math Important for Programers?
Agile is a cancer that we have to eliminate from the industry. — Erik Meijer
What's Disjoint Union, Sum Type? (on its own page)
Seymour Papert died, 88. Inventor of non-paren lisp: Logo
Seymour Papert died, 88. Invented “logo”, probably first non-paren lisp. Logo pioneered “turtle graphics”, we see in Scratch and Processing languages today.
I never learned logo, but ~1992 read a lot story about it, fascinated. I was busy doing Mathematica, this Visual Dictionary of Special Plane Curves
particularly interesting about logo is that there's a 3 volumes book 〈Computer Science Logo Style〉 Buy at amazon by Brian Harvey, another lisp pillar.
Brian Harvey is another lisp pillar.
History of OCaml Syntax, and The Next 700 Programming Languages
OCaml Syntax Sucks (heavily expanded, on its own page.)
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