Notices by Dan Drake 🦆 (ddrake@mathstodon.xyz)

Years ago I loved the game Trainyard -- it was a mobile game and was a lovely masterpiece geometric logic puzzle.

https://www.trainyard.ca/

(It's so good, folks went and proved theorems about it: https://www.google.com/search?q=https://doi.org/10.1016/j.tcs.2017.09.039&authuser=1. And of course the connection between train tracks, switching, and logic gates is pretty obvious.)

I finished every puzzle!

Sadly, the game has never been updated and is now old enough so that it doesn't even work on mobile devices.

Fortunately someone is keeping the game alive! Play in your browser:

https://github.com/micoloth/OpenTrainyard

Hooray! Maybe someone is making new levels...!

#trainyard #logicpuzzles #logic #trains #games

The OG Trainyard is defunct-ish, but there are what seem like some new, closely related games that seem to scratch the same itch:

Teeny Tiny Trains: https://www.shortcircuitstudio.com/teeny-tiny-trains

Railbound: https://www.gameflare.com/online-game/railbound/

Cosmic Express: https://cosmicexpressgame.com/

The real puzzle here, though is an optimization problem: how do I find time to play these games, given the approximately-infinite number of other things I have to do?

Hivemind: I recall recently reading about some kind of note-taking sort of tool that helps you when you're doing research on something.

I recall that it was aimed at seamlessly integrating the distinct, but related activities of *sense-making* and *exploration*.

For example, you're learning a topic, and you explore: you do some searches, open a bunch of tabs for various web pages, get a bunch of articles. You're just exploring, gathering,

Then, you start *sense-making*: you take all the various articles, etc, and start organizing and, well, making sense of them. Putting things in your own words, organizing what you've found into something useful for you.

I'm recalling someone like Andy Matsuchak talking about this?

What am I not-really-remembering?

Racket folks: so I hear that Racket is good for making DSLs, and that it's a "programming language programming language".

For example, there's Scribble, for writing documents -- which I'd describe as "Racket's TeX": https://docs.racket-lang.org/scribble/

I want to learn a bit about this, and have an idea for a little DSL I'd like to make: it would describe hikes, walks, bike routes, etc -- any sort of 1-d path. It would describe waypoints, landmarks, elevation, directions, maybe alternate routes, and so on.

The neat thing would be "compilers" for such a DSL: imagine "compiling" such a hike/path into a regular map with the path...or an elevation profile...or a textual list of directions...or a GPX file.

#racket folks, what are some good resources for getting started? I'm poking around but would like to hear your thoughts.

@johncarlosbaez this reminds me of Scott's "Seeing Like a State". And the useful advice on "don't be a dick" reminds me of an interview where Douglas Rushkoff mentioned speaking with billionaires on how they should try to handle their bunkers:

https://www.resilience.org/stories/2023-01-13/the-response-survival-of-the-richest-with-douglas-rushkoff/

The billionaires were all worried about a sudden, global collapse of civilization into a Hobbesian, Mad Max sort of world. So they build their safety bunkers to survive it. But they need to hire guards and so on, because they're billionaires and that's how they think.

But -- the billionaires think -- how do I ensure the guards stay loyal? And how much armament would I need to protect me from my now-savage neighbors?

They hired Rushkoff to advise them.

But of course, the best way to deal with neighbors who want to loot your bunker and kill you is...to be nice to your neighbors and help them. That is: don't be a dick. Be on Team Human, as Rushkoff would say.

The other evening I started reading Daniel Temkin's "44 Esolangs":

https://danieltemkin.com/Esolangs

I just read the introduction and skimmed a few of the languages.

In the following eight hours, I thought of three esolangs of my own!

This book may be slightly deadly to my productivity...

#programming #esolang

Thinking about esoteric programming languages inspired me to imagine...esoteric text editors!

If you can say "a programming language that [insert some interesting thing]" you can do the same with text editors, right?

A couple I thought of:

A text editor that will only write a file to an *existing* file whose contents are very different from the one being edited. I'd call it Clobber.

A text editor that will save every file as an image -- take, say, the UTF-8 representation of the text, and take 3-byte sequences at a time to write pixels of an image.

A text editor that will only save a file if the alphabetical text can be interpreted as a sequence of chemical element abbreviations. So it would save "tick" -- titanium, carbon, potassium -- but if the file had "hello" it wouldn't because there's no way to represent the Ls.

...and what's interesting about thinking about such esoteric text editor behavior is that one realizes many of those ideas could be implemented in emacs.

#emacs #esolang #esoeditor

@marcoxa indeed!

Emacs is a sort of meta-esoteric text editor. It can emulate any other esoteric text editor.

(...or...can it? My challenge now: think of an amusing esoteric text editor description that emacs can't do. Hrm...)

I know I posted about this but can't find it -- but today I learned of the --human-numeric-sort option to the GNU "sort" command!

"sort -h" is smart about suffixes: it knows that 999K is less than 1M, and so on.

It's obviously designed to handle input from things like "du -h", which means

du -h | sort -h

does exactly what you want!

#linux #terminal

@inthehands you beat me to this -- I was going to post that exact sentiment.

Somali immigrants are my neighbors too. They are fellow Saint Paul residents, Twin Citians, Minnesotans. For Trump to call them garbage is just disgusting.

@inthehands this seems pretty obvious, and effective, right?

We have carbon tax for CO2 emissions; all sorts of sin taxes on tobacco and alcohol; related taxes on sugary drinks in some places -- and, very closely related to plastic in general, there's research showing that taxes on plastic bags are very effective: https://www.science.org/doi/10.1126/science.adp9274

This seems like a bog-standard case of increasing the market price to reflect economic externalities...

I used to teach at KAIST and this is a great development from their CS folks -- provably correct translation from C to Rust.

https://news.kaist.ac.kr/newsen/html/news/?mode=V&mng_no=54270

#kaist #c #rust

@inthehands I hope so!

I am also hoping I can talk about surreal numbers sometime, too...

@soaproot @inthehands I am still dabbling, mostly, in the surreals, but would be delighted (subject to time availability, sigh...) to learn more!

🧵 1/2

Earlier this semester, trying to look all super ambitious and so on, I volunteered to speak at the department seminar. My talk is next week, and they sent out a flyer advertising it...and suddenly it's on nearly EVERY office door near me. So now I'm all nervous because it seems like every single one of my colleagues and all sorts of other people are going to show up, and maybe my talk actually isn't that good. Ack.
Flyer screenshot below. Here's hoping I somehow live up to the hype this Tuesday.

But that's not the only problem...

@inthehands oooh, me too. I would love if they would, say, throw a bunch of AI stuff at notifications so that I could give it feedback on what I want shown, not shown, which make noise or not, and so on -- and the system would extract patterns and do it for me.

The other thing I want is a night vision flashlight: sometimes I get up at night and need a little light, but I don't want the crazy bright regular flashlight. Instead, I'd like something that just turns the entire main screen red. That would be less bright, red, but enough for me to see.

(I hacked this up by just making a tiny web page with an entirely red background that I load up in my browser when I want this "flashlight".)

Achievement unlocked: I have ridden a bicycle with square wheels. This is from earlier this week at our department's "block party" for our majors and interested students.

I'm proud (and a bit intimidated TBH) to work in the same department as Stan Wagon, the mathematician who made the square wheel bike -- and the surface on which you can ride it.

https://stanwagon.com/

https://www.macalester.edu/mscs/multimedia/squarewheeledbike/squarewheelbike/

#HeyMac #macalestercollege #bicycling #catenary

@inthehands wait, what's the fourth????

@inthehands I think you could describe me as "-1 times Paul".

I am a super morning person, am fine with the morning slot, and...well, I guess I don't have an opinion (yet?) on the scheduling.

That said, if this is a class I'm also teaching, I'm happy to do the first / earliest time slot.