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I don't know Olin Shivers but I've read enough of his writing to know that this acknowledgements section was written with tongue in cheek, and in fact it's a funny enough piece of writing that I've shared it a number of times like the grandparent comment did.

arundeloon An Illustrated Guide to Useful Command Line Tools

I guess the author was thinking of how cat's original purpose is to concatenate multiple files, not show just one file. (But I certainly don't think using cat in the latter way is a misuse.)

There's also a commonly noted "unnecessary use of cat" where people do this:

  cat file.txt | grep foo

instead of this:

  <file.txt grep.foo

but that's not relevant to bat (which can be used unnecessarily in the same way).

arundeloon Show HN: Bel

(1) lack of primitive hash tables (2) lack of primitive arrays

I'll note that if there are primitive arrays and the compiler optimizes arithmetic, the rest of the hash table can be implemented in Bel.

Also, maybe a Sufficiently Smart Compiler could prove that a list's cdrs will never change, store it in cdr-coded form, and treat it like an array (with the ability to zoom right to, say, element 74087 without chasing a bunch of pointers).

arundeloon A Pixel Is Not A Little Square (1995) [pdf]

http://productionadvice.co.uk/no-stair-steps-in-digital-audi...

The “stair-steps” you see in your DAW when you zoom up on a digital waveform only exist inside the computer. [...] When digital audio is played back in the Real World, the reconstruction filter doesn’t reproduce those stair-steps – and the audio becomes truly analogue again.

arundeloon Cocktail Similarity

This all sounds like it would make an interesting blogpost/article if you're into writing one.

arundeloon Firefox 66 to block automatically playing audible video and audio

I'm surprised people put up with them

I don't like them at all but I do most of my Netflixing on my iPhone, where it doesn't happen.

(When I do go to the Netflix site in a web browser I sometimes temporarily use "Mute site" which is a pretty crazy thing for a site for watching movies to make you want to do!)

arundeloon How to create an OS from scratch – tutorial

https://compilers.iecc.com/crenshaw/

arundeloon GNU Mcron

“[A]lmost anything ending in ‘x’ may form plurals in ‘-xen’ (see VAXen and boxen in the main text). Even words ending in phonetic /k/ alone are sometimes treated this way; e.g., ‘soxen’ for a bunch of socks. Other funny plurals are the Hebrew-style ‘frobbotzim’ for the plural of ‘frobbozz’ (see frobnitz) and ‘Unices’ and ‘Twenices’ (rather than ‘Unixes’ and ‘Twenexes’; see Unix, TWENEX in main text). [...] The pattern here [...] is generalization of an inflectional rule that in English is either an import or a fossil (such as the Hebrew plural ending ‘-im’, or the Anglo-Saxon plural suffix ‘-en’) to cases where it isn't normally considered to apply. This [...] is grammatical creativity, a form of playfulness.”

http://catb.org/jargon/html/overgeneralization.html

arundeloon Xz format inadequate for long-term archiving (2017)

I upvoted this because it seems to make some good points and I think the topic is interesting and important, but I can't understand why the "Then, why some free software projects use xz?" section does not mention xz's main selling point of being better than other commonly used alternatives at compressing things to smaller sizes.

https://www.rootusers.com/gzip-vs-bzip2-vs-xz-performance-co...

arundeloon Decades-Old Graph Problem Yields to Amateur Mathematician

That is what it means. Note that the lines ("edges" in graph theory terms) can cross each other.

Nelson asked: What is the smallest number of colors that you’d need to color any such graph, even one formed by linking an infinite number of vertices?

The Wikipedia page describes the infinite-vertices version of this graph as

an infinite graph with all points of the plane as vertices and with an edge between two vertices if and only if the distance between the two points is 1.

This of course is impossible to draw but Wikipedia shows seven-vertex and ten-vertex subgraphs of it:

https://en.wikipedia.org/wiki/Hadwiger%E2%80%93Nelson_proble...

arundeloon List of command line tools for manipulating CSV, XML, HTML, JSON, INI, etc.

I'll look into xmllint. I currently use HTML Tidy for this:

  tidy -xml -indent -wrap 0

  tidy -xml -indent -wrap 0 -quiet

arundeloon The screen that set off the ballistic missile alert on Saturday

Formatting the quote like this makes it too wide to be readable on my phone without repeatedly scrolling right then left. Even in landscape mode the first line ends with the "b" of "brightly painted".

A lot of people format quotes with italics, as in this example:

https://news.ycombinator.com/item?id=7485333

HN formatting documentation:

https://news.ycombinator.com/formatdoc

arundeloon Useful Mental Models (2016)

The efficient-market hypothesis is an idea that already has a well-known name. In the article the words are a Wikipedia link.

arundeloon SQL Keys in Depth

RFC 2392 Message-ID values are supposed to be unique, but they may not be if the software generating them is buggy. I remember reading somewhere about some email program that assumed they were unique (in effect using them as a natural key). If you were unlucky enough to get messages with identical Message-ID values, all but one would disappear.

arundeloon ‘Saluton’: the surprise return of Esperanto

Esperanto has many many more speakers! (People joke about Klingon having more but it's not true.) Really accurate numbers are hard to come by but even based on estimates, it's no contest:

"Arika Okrent guessed in her book In the Land of Invented Languages that there might be 20–30 fluent [Klingon] speakers."[1]

"In 2009 Lu Wunsch-Rolshoven used 2001 year census data from Hungary and Lithuania as a base for an estimate, resulting in approximately 160,000 to 300,000 to speak [Esperanto] actively or fluently throughout the world, with about 80,000 to 150,000 of these being in the European Union."[2]

In fact, Klingon has fewer total speakers than Esperanto has native speakers:

"As of 1996, there were 350 or so attested cases of families with native Esperanto speakers. Estimates from associations indicate that there are currently around 1,000 Esperanto-speaking families, involving perhaps 2,000 children. In all known cases, speakers are natively bilingual, or multilingual, raised in both Esperanto and either the local national language or the native language of their parents."[3]

(Also Esperanto is much easier than Klingon, has much more material to read, and is spoken by a wider variety of people than just science fiction fans, though there are plenty of those too.)

[1]: https://en.wikipedia.org/wiki/Klingon_language#Speakers

[2]: https://en.wikipedia.org/wiki/Esperanto#Number_of_speakers

[3]: https://en.wikipedia.org/wiki/Native_Esperanto_speakers

EDIT: The "160,000 to 300,000" quote was from an older version of the Wikipedia page (I based this comment on an old comment of mine). The current version has various estimates, including Lindstedt's ballpark figures of "10,000 speak it fluently" and "100,000 can use it actively".

arundeloon More Gotchas of Defer in Go, Part II

It would be nice if Go made a new i for each iteration of the loop.

Lua 5.0 made just one loop variable per loop, like Go apparently does. When I first ran into this behavior, I thought that, although it wasn't what I expected, it made at least as much sense as what I was expecting. Since then, every single time I've been in a situation where the two ways of doing it gave different results, I've wanted the "separate variable for each iteration" behavior, so I was glad when Lua's creators changed loop variables to work like this in Lua 5.1.

(Before this change I would just do the Lua equivalent of your "Creates a new `i`" line.)

arundeloon Microsoft Adds an OpenSSH Client to Windows 10

I use forward slashes a lot on Windows but tab completion in cmd.exe only works with backslashes.

arundeloon The Algorithms Behind Moana’s Animated Ocean

I have talked to other people who found CGI Peter Cushing convincing but I did not. I'm confident I would have picked him out as CGI even if I hadn't recognized him as a long-dead actor. (Same for CGI young Carrie Fisher.)

(Still impressive, though, and I expect the uncanny valley to be bridged within the next five, maybe ten years.)

arundeloon Doxing the hero who stopped WannaCry was irresponsible and dumb

https://en.wikipedia.org/wiki/Doxing

arundeloon The licensing program for MP3-related patents has been terminated

Wikipedia says that MP3's last patent expired in the United States last month:

If only the known MP3 patents filed by December 1992 are considered, then MP3 decoding has been patent-free in the US since 22 September 2015 [...] If the longest-running patent mentioned in the aforementioned references is taken as a measure, then the MP3 technology became patent-free in the United States on 16 April 2017 [...].

https://en.wikipedia.org/wiki/MP3#Licensing.2C_ownership_and...

Wikipedia also says (unless I'm missing something) that all the MP3 patents have already expired everywhere else too. If this is true, then Fraunhofer is ending their licensing program just because they don't want to bother getting people to pay for something they can now legally have for free.

arundeloon A quick start guide to Commodore 64 assembly programming on Windows (2011)

Ah, last time I looked at this I thought, "This is cool but it's too bad it doesn't have EQU or some other way to give symbolic names to constants."

Now it does!

  define appleL  $00 ; screen location of apple, low byte

(Looks like the feature was added in November 2014.)

arundeloon Time to Take a Stand

Unfortunately I can't find a source for this but I saw someone saying recently (and it makes sense) that a lot of congress fax numbers just convert the fax to an email message rather than physically printing it out.

arundeloon Don't Mess with Texas – TI-99/4A Megademo [video]

I'm talking about 8-bit microcomputers in general, from the late seventies to the mid-to-late eighties:

https://en.wikipedia.org/wiki/Home_computer#Notable_home_com...

EDIT: I owned a Commodore 64 and a TRS-80 in the eighties, and used an Apple IIe at school. These were all programmable in Basic, and although the C64 was clearly the most powerful, they were all similar in power compared to, say, an Amiga.

arundeloon Wraparound tile maps with sphere topology

There are spots where a vertex would have two hexagons at it rather than three.

For instance, look at the border between the upper left and lower left islands. In this picture, those two islands are only touching along a third of the border that they share on the sphere. If you look at the leftmost point of where they are touching in this picture, that's a vertex that would have only two hexagons.

arundeloon Don't Mess with Texas – TI-99/4A Megademo [video]

(Not relevant to this demo in particular, just a piece of trivia I only learned in the past few years:) It makes sense to think of the TI-99 as part of the 8-bit microcomputer boom of the 1980s (Commodore 64, Apple II, TRS-80), but it actually had a 16-bit processor! (Which communicated with most of the rest of the computer through an 8-bit bus.)

https://en.wikipedia.org/wiki/Texas_Instruments_TI-99/4A#Fir...

arundeloon FAP80, a retro computer without the retro baggage

Read about Thomas Tempelmann's and Mike Pall's disk copy programs for the Commodore 64 and 1541 disk drive:

http://www.pagetable.com/?p=647

http://www.pagetable.com/?p=656

From the second article:

It worked by transferring the "live" GCR-encoded data from the 1541's disk head to the C64 and simultaneously doing a fast checksum. Part of the checksumming was done on the 1541, part was done on the C64. There simply weren't enough cycles left on either side! Most of the transfer happened asynchronously by adjusting for the slightly different CPU frequencies and with only a minimum number of handshakes. This meant meticulous cycle counting and use of some odd tricks.

arundeloon Grokking Python 3’s str

(pro tip: a b'foo' object in Python2.7 or Python3 isn't "a bytes", it's "a bytestring".)

Quotes from the Python 3 documentation:

Bytes literals are always prefixed with 'b' or 'B'; they produce an instance of the bytes type instead of the str type.

class bytes([source[, encoding[, errors]]])

Return a new “bytes” object, which is an immutable sequence of integers in the range 0 <= x < 256. bytes is an immutable version of bytearray – it has the same non-mutating methods and the same indexing and slicing behavior.

https://docs.python.org/3/library/functions.html#bytes

https://docs.python.org/3/reference/lexical_analysis.html#st...

arundeloon A vi-centric family tree of editors (2000)

"vi"[1] is a very influential text editor created in the 1970s (and still used today). This "family tree" show a bunch of other old text editors that directly or indirectly influenced or inspired vi. (For example, George Coulouris's "em" was based on Ken Thompson's "ed". Bill Joy and Chuck Haley's first version of "ex" -- an ancestor of vi -- was based on "em".)

[1]: https://en.wikipedia.org/wiki/Vi

arundeloon Which Language Uses the Most Sounds?

If you're not already familiar with https://en.wikipedia.org/wiki/Toki_Pona , check it out. "Both its sound inventory and phonotactics (patterns of possible sound combinations) are found in the majority of human languages and are therefore readily accessible."