Hacker News: leontrolski

New comment by leontrolski in "All of human cooking compressed into 2 megabytes"

leontrolski — Wed, 27 May 2026 12:10:14 +0000

Neat.

I'm trying to compress recipes into little schematics https://leontrolski.github.io/recipes.html

New comment by leontrolski in "Generalised plusequals"

leontrolski — Sat, 25 Apr 2026 08:55:08 +0000

What would be the equivalent to this in Haskell (with or without lens):

    cat = Cat(age=3)
    l = [1, [2, cat], 4]
    alt l[1][1].age.=9

That would give us l equal to:

    [1, [2, Cat(age=9)], 4]

New comment by leontrolski in "Generalised plusequals"

leontrolski — Sat, 25 Apr 2026 08:41:13 +0000

This is surprising to me:

  l[1][1].age:9
  # (1,(2,{"age":9}),4)

How come it doesn't return just:

  {"age":9}

Or is there something totally different going on with references here? As in, how is this different to:

  l_inner = l[1][1]
  l_inner.age:9

Generalised plusequals

leontrolski — Fri, 24 Apr 2026 21:34:25 +0000

Article URL: https://leontrolski.github.io/alt.html

Comments URL: https://news.ycombinator.com/item?id=47896086

Points: 16

# Comments: 11

“Disregard That” Attacks

leontrolski — Wed, 25 Mar 2026 23:11:34 +0000

Article URL: https://calpaterson.com/disregard.html

Comments URL: https://news.ycombinator.com/item?id=47524519

Points: 129

# Comments: 94

New comment by leontrolski in "Is anybody else bored of talking about AI?"

leontrolski — Tue, 24 Mar 2026 21:58:54 +0000

Yes, AI or no AI, tell me about something actually interesting that you're working on.

Currently it feels a bit like everyone is talking about what new editor they're using. I don't care about that type of developer tooling very much. AI isn't coming up with some exciting new database, type system, etc etc.

"Look at how I'm able to web dev x% faster" because of LLMs is boring.

Aldo's Game of Music

leontrolski — Wed, 04 Mar 2026 22:34:28 +0000

Article URL: https://www.aldodevos.nl/game_of_music/

Comments URL: https://news.ycombinator.com/item?id=47254933

Points: 1

# Comments: 0

National Raisin Reserve

leontrolski — Sun, 28 Dec 2025 09:30:37 +0000

Article URL: https://en.wikipedia.org/wiki/National_Raisin_Reserve

Comments URL: https://news.ycombinator.com/item?id=46409705

Points: 6

# Comments: 0

Show HN: I 3D printed a running buggy

leontrolski — Mon, 17 Nov 2025 20:57:29 +0000

Article URL: https://leontrolski.github.io/buggy.html

Comments URL: https://news.ycombinator.com/item?id=45958194

Points: 1

# Comments: 0

New comment by leontrolski in "Venn Diagram for 7 Sets"

leontrolski — Sat, 08 Nov 2025 11:13:52 +0000

Ditto, another Upset blog post - https://leontrolski.github.io/upset.html

Using Python 3.14 template strings to write Python

leontrolski — Tue, 07 Oct 2025 20:30:28 +0000

Article URL: https://leontrolski.github.io/trolskgen.html

Comments URL: https://news.ycombinator.com/item?id=45508428

Points: 3

# Comments: 1

New comment by leontrolski in "A Early History of Algebraic Data Types"

leontrolski — Thu, 25 Sep 2025 19:18:32 +0000

Lovely writeup!

> Pascal did not have sum types because Wirth thought they were less flexible than untagged unions

I'm not sure whether my dream language would have tagged or untagged unions (Scala 3 has both it seems). I'd be interested if anyone has any further points of comparison beyond:

Tagged unions, eg. in Rust: enum Tagged {A(i64), B(String), C(f64)} Untagged unions, eg. in typed Python: Tagged = int | str | float

Tagged unions are better as you can represent duplicated types and types with no data, eg: enum Tagged {A, B(f64), C(f64)}

Untagged unions are better as you can willy nilly create new subsets and intersections of types. I find often in AST-ish work I want to express eg: def f(x: A | B | C) -> A | B

New comment by leontrolski in "Do not download the app, use the website"

leontrolski — Sat, 26 Jul 2025 09:03:01 +0000

A reminder of all the features available right now with PWAs - https://whatpwacando.today

Cheeky Python Shell Script

leontrolski — Wed, 16 Jul 2025 10:35:25 +0000

Article URL: https://leontrolski.github.io/python-script.html

Comments URL: https://news.ycombinator.com/item?id=44580676

Points: 3

# Comments: 1

New comment by leontrolski in "Postgres LISTEN/NOTIFY does not scale"

leontrolski — Fri, 11 Jul 2025 04:36:32 +0000

> also fast when transactions are held open

In my linked example, on getting the item from the queue, you immediately set the status to something that you're not polling for - does Postgres still have to skip past these tuples (even in an index) until they're vacuumed up?

New comment by leontrolski in "Postgres LISTEN/NOTIFY does not scale"

leontrolski — Thu, 10 Jul 2025 21:00:49 +0000

I'd be interested as to how dumb-ol' polling would compare here (the FOR UPDATE SKIP LOCKED method https://leontrolski.github.io/postgres-as-queue.html). One day I will set up some benchmarks as this is the kind of thing people argue about a lot without much evidence either way.

Wasn't aware of this AccessExclusiveLock behaviour - a reminder (and shameless plug 2) of how Postgres locks interact: https://leontrolski.github.io/pglockpy.html

Senior Engineer tries Vibe Coding [video]

leontrolski — Fri, 04 Jul 2025 07:36:00 +0000

Article URL: https://www.youtube.com/watch?v=_2C2CNmK7dQ

Comments URL: https://news.ycombinator.com/item?id=44462091

Points: 2

# Comments: 0

Show HN: trolskgen – Ergonomic Codegen for Python

leontrolski — Thu, 26 Jun 2025 14:45:30 +0000

Article URL: https://github.com/leontrolski/trolskgen

Comments URL: https://news.ycombinator.com/item?id=44387972

Points: 2

# Comments: 1

My dream thermostat (2024)

leontrolski — Tue, 06 May 2025 22:11:24 +0000

Article URL: https://leontrolski.github.io/thermostat.html

Comments URL: https://news.ycombinator.com/item?id=43910155

Points: 48

# Comments: 68

New comment by leontrolski in "Show HN: Tkintergalactic - Declarative Tcl/Tk UI Library for Python"

leontrolski — Mon, 05 May 2025 21:23:13 +0000

I plan on using it for semi throw away UIs for things where I don't want the user to have to spin up a Web server. Right now there's no canvas support, but there is that kind of thing in the Tk/Tcl docs (linked in the project). I probably need to add a way to reference a specific Widget so you can access the raw name and run taw Tcl against it.