6 ms·

Clojure's immutable HAMTs are still a superpower nearly 20 years later. They've been copied in pretty much every language as a library (I did so myself in Zig)

by xeubie 5mo ago

Clojure's immutable HAMTs are still a superpower nearly 20 years later. They've been copied in pretty much every language as a library (I did so myself in Zig) but what really makes it work well in Clojure is the fact that they're built into the language, so the entire ecosystem is built around them. Libraries that were made independently usually fit together like a glove because they are all just maps/vectors in -> maps/vectors out.

dapperdrake 5mo ago
I thought it cheesy at the time. Then I tried clojure. "The value of values". Indeed. Q.e.d. No notes.
- nesarkvechnep 5mo ago
  Lisp programmers know the value of everything and the cost of nothing.
  - andersmurphy 5mo ago
    Apart from Andy Gavin [1]. He knows both the cost and the value of everything. [1] https://en.wikipedia.org/wiki/Game_Oriented_Assembly_Lisp https://en.wikipedia.org/wiki/Game_Oriented_Assembly_Lisp
  - jjtheblunt 5mo ago
    sbcl's optimizers knowing the cost of everything is the gamble, no?
iLemming 5mo ago
Yeah, they are so underappreciated - the practical differences in designing, delivering and maintaining software are real. Initially you see small differences "What's the point? I can write that in Python too... maybe it's not as delightful, but who cares?...", etc. Yet over time small annoyances accumulate and become an endless stream of headaches. I see it over and over again - I work on a team where we have codebases in different languages, and some services written in Clojure. Immutability by default is a game of a different league.
packetlost 5mo ago
Yeah. I do wish there was something that was like Clojure with a TypeScript or Go-like nominal typing, but I do feel myself missing types a lot less with Clojure compared to other languages.
- ux266478 5mo ago
  Type annotations mix poorly with s-expressions imo. Try an ML, which answers the same question of "How do we represent the lambda calculus as a programming language?"
  - packetlost 5mo ago
    There's already type annotations in Clojure and they look fine (though are a bit noisy). There are type algorithms that don't need annotations to provide strong static guarantees anyways, which is the important part (though I'm not sure you can do that with nominal types?). I think TypeScript and Go's syntaxes are a bad fit for s-expr but the idea probably isn't.
  - genxy 5mo ago
    Isn't this like saying types mix poorly with ASTs?
slowmovintarget 5mo ago
HAMT -> Hashed Array Mapped Trie for those wondering. https://en.wikipedia.org/wiki/Hash_array_mapped_trie https://en.wikipedia.org/wiki/Hash_array_mapped_trie (The acronym is expanded in the article, but a ways down.)
kgwxd 5mo ago
I think I know and love more about clojure than any language I actually use. I rewatch hickey talks anytime Im a little stuck on a big problem/idea and there's almost always another "ah ha" moment for me. If the places i work were already on the JVM, i would have switched a decade ago, but I've been in .net world my whole career.
- genxy 5mo ago
  Have you thought about moving to a Clojure shop?
- iLemming 5mo ago
  You don't need team's approval of your choices for using a tool, a technique, an idea. A tool remains useful even if nobody else but only you understand its practicality. There are days when I deal with projects where some don't even know about Clojure's existence, but I still may use babashka to understand the data flow. Having a Clojure REPL around is immensely handy, slashing through data that flows down the APIs is the best - JSON is so lame and annoying to deal with - even LLMs often can't get the jq filter syntax right, or when they do, it looks terrifyingly cryptic and confusing. Or sometimes I'd fire up an nbb REPL with Playwright - just to reproduce some issue without having to manually click through things.
bjoli 5mo ago
Didnt they move to CHAMP? Otherwise, that seems like a waste of resources. They are literally the same but CHAMPs are a little faster in just about every way. I am still a bit disappointed that they didn't change to RRB trees or copy the scala vectors instead of the built in ones. Iirc the scala vectors are faster in general while providing a bunch of benefits (at the cost of code complexity though, but even a better RRB list implementation instead of the scala finger trees would allow for that). I wrote an RRB tree implementation in c# just for fun [0], and while they are harder than the tries of clojure, the complexity is pretty well contained to some functions. 0: https://github.com/bjoli/RrbList/tree/main/src/Collections https://github.com/bjoli/RrbList/tree/main/src/Collections
gsk22 5mo ago
> Libraries that were made independently usually fit together like a glove because they are all just maps/vectors in -> maps/vectors out. This is also the biggest weakness of Clojure (IMO). When everything is "just data", you spend a lot of time digging deep in libraries trying to figure out exactly what shape the data should take. Additionally, the shape of input data is almost never validated, so you spend lots of time debugging nasty type errors far from the place where bad data entered the program. There have been some abortive attempts at solving this with things like spec, Prismatic Schema, etc, but nothing that has taken hold like TypeScript did with JS. I'm still waiting for my dream language with the flexibility and immutability of Clojure, but without the pain points of an anything-goes attitude towards typing and data shape.
- chii 5mo ago
  > When everything is "just data", you spend a lot of time digging deep in libraries trying to figure out exactly what shape the data should take or that is a good spend of time where you familiarize yourself with said library (as they say, the documentation is the code!). Usually the library is well written enough that you can browse through the source code and immediately see the pattern(s) or keys. The additional experimentation with the REPL means you can just play around and visually see the data in the repl. A spec does similar (and it does make it easier to seek through the source to find it).
  - psd1 5mo ago
    I've often got value from digging through libraries (in other languages), but I've almost always had the feeling that I'm not "doing it right", or that someone somewhere isn't "doing it right". Logically, the concept of encapsulation doesn't extend to meta-coding, but it feels like it should, by symmetry. It feels like I'm breaking encapsulation if I use the knowledge I gain from poking around when I code to the library. I'm fumbling at the concept of a library surface not being self-describing but I suspect I lack some concepts; does this thought lead anywhere? Can anyone give me a clue?
    - chii 5mo ago

by xeubie 5mo ago

dapperdrake 5mo ago

I thought it cheesy at the time. Then I tried clojure. "The value of values". Indeed. Q.e.d. No notes.

nesarkvechnep 5mo ago
Lisp programmers know the value of everything and the cost of nothing.
- andersmurphy 5mo ago
  Apart from Andy Gavin [1]. He knows both the cost and the value of everything. [1] https://en.wikipedia.org/wiki/Game_Oriented_Assembly_Lisp https://en.wikipedia.org/wiki/Game_Oriented_Assembly_Lisp
- jjtheblunt 5mo ago
  sbcl's optimizers knowing the cost of everything is the gamble, no?

iLemming 5mo ago

Yeah, they are so underappreciated - the practical differences in designing, delivering and maintaining software are real. Initially you see small differences "What's the point? I can write that in Python too... maybe it's not as delightful, but who cares?...", etc. Yet over time small annoyances accumulate and become an endless stream of headaches. I see it over and over again - I work on a team where we have codebases in different languages, and some services written in Clojure. Immutability by default is a game of a different league.

packetlost 5mo ago

Yeah. I do wish there was something that was like Clojure with a TypeScript or Go-like nominal typing, but I do feel myself missing types a lot less with Clojure compared to other languages.

ux266478 5mo ago
Type annotations mix poorly with s-expressions imo. Try an ML, which answers the same question of "How do we represent the lambda calculus as a programming language?"
- packetlost 5mo ago
  There's already type annotations in Clojure and they look fine (though are a bit noisy). There are type algorithms that don't need annotations to provide strong static guarantees anyways, which is the important part (though I'm not sure you can do that with nominal types?). I think TypeScript and Go's syntaxes are a bad fit for s-expr but the idea probably isn't.
- genxy 5mo ago
  Isn't this like saying types mix poorly with ASTs?

slowmovintarget 5mo ago

HAMT -> Hashed Array Mapped Trie for those wondering. https://en.wikipedia.org/wiki/Hash_array_mapped_trie https://en.wikipedia.org/wiki/Hash_array_mapped_trie (The acronym is expanded in the article, but a ways down.)

kgwxd 5mo ago

I think I know and love more about clojure than any language I actually use. I rewatch hickey talks anytime Im a little stuck on a big problem/idea and there's almost always another "ah ha" moment for me. If the places i work were already on the JVM, i would have switched a decade ago, but I've been in .net world my whole career.

genxy 5mo ago
Have you thought about moving to a Clojure shop?
iLemming 5mo ago
You don't need team's approval of your choices for using a tool, a technique, an idea. A tool remains useful even if nobody else but only you understand its practicality. There are days when I deal with projects where some don't even know about Clojure's existence, but I still may use babashka to understand the data flow. Having a Clojure REPL around is immensely handy, slashing through data that flows down the APIs is the best - JSON is so lame and annoying to deal with - even LLMs often can't get the jq filter syntax right, or when they do, it looks terrifyingly cryptic and confusing. Or sometimes I'd fire up an nbb REPL with Playwright - just to reproduce some issue without having to manually click through things.

bjoli 5mo ago

Didnt they move to CHAMP? Otherwise, that seems like a waste of resources. They are literally the same but CHAMPs are a little faster in just about every way. I am still a bit disappointed that they didn't change to RRB trees or copy the scala vectors instead of the built in ones. Iirc the scala vectors are faster in general while providing a bunch of benefits (at the cost of code complexity though, but even a better RRB list implementation instead of the scala finger trees would allow for that). I wrote an RRB tree implementation in c# just for fun [0], and while they are harder than the tries of clojure, the complexity is pretty well contained to some functions. 0: https://github.com/bjoli/RrbList/tree/main/src/Collections https://github.com/bjoli/RrbList/tree/main/src/Collections

gsk22 5mo ago

> Libraries that were made independently usually fit together like a glove because they are all just maps/vectors in -> maps/vectors out. This is also the biggest weakness of Clojure (IMO). When everything is "just data", you spend a lot of time digging deep in libraries trying to figure out exactly what shape the data should take. Additionally, the shape of input data is almost never validated, so you spend lots of time debugging nasty type errors far from the place where bad data entered the program. There have been some abortive attempts at solving this with things like spec, Prismatic Schema, etc, but nothing that has taken hold like TypeScript did with JS. I'm still waiting for my dream language with the flexibility and immutability of Clojure, but without the pain points of an anything-goes attitude towards typing and data shape.

chii 5mo ago
> When everything is "just data", you spend a lot of time digging deep in libraries trying to figure out exactly what shape the data should take or that is a good spend of time where you familiarize yourself with said library (as they say, the documentation is the code!). Usually the library is well written enough that you can browse through the source code and immediately see the pattern(s) or keys. The additional experimentation with the REPL means you can just play around and visually see the data in the repl. A spec does similar (and it does make it easier to seek through the source to find it).
- psd1 5mo ago
  I've often got value from digging through libraries (in other languages), but I've almost always had the feeling that I'm not "doing it right", or that someone somewhere isn't "doing it right". Logically, the concept of encapsulation doesn't extend to meta-coding, but it feels like it should, by symmetry. It feels like I'm breaking encapsulation if I use the knowledge I gain from poking around when I code to the library. I'm fumbling at the concept of a library surface not being self-describing but I suspect I lack some concepts; does this thought lead anywhere? Can anyone give me a clue?
  - chii 5mo ago