The best example of all is Prolog. It is always held up as the paradigmatic representative of logic programming, a rare language paradigm. But it doesn't need to be a language. It is really a collection of algorithms which should be a library in every language, together with a nice convention for expressing Prolog things in that language's syntax.
(My comment is slightly off-topic to the article but on-topic to the title.)
The main thing about prolog isn't the algorithms. In fact, the actual depth-first search isn't even part of the standard.
The nice thing about prolog is that you write logical rules, and they can get used in whatever order and direction that is needed. By direction, I mean that if you define "a grandparent is the parent of a parent", you can now use that rule not just to evaluate whether one person is a parent (or to find all grandparents) but also to conclude that if you know someone is a grandparent, and they are the parent of some one, then that person is someone's parent. Ok, it can also do recursion, so if you define an ancestor as a parent or the parent of an ancestor it will recurse all the way up the family tree. Neat.
You could write some kind of runtime that takes c code and brute-forces its way from outputs to inputs, except that regular imperative code allows for all kinds of things that make this impossible (e.g. side-effects). So then, you'd be limited to some subset, essentially ending up with a domain specific language again, albeit with the same syntax as your regular code, rather than those silly :- symbols (although LISP looks much sillier than prolog IMHO).
What the article is getting at is that if you use some features specific to a language, it's hard to embed your code as a library in another language. But is it? I mean, DLLs don't need to be written in the same language, there's stuff like JNI, and famously there's stuff like pytorch and tensorflow that runs CUDA code from python.
> By direction, I mean that if you define "a grandparent is the parent of a parent", you can now use that rule not just to evaluate whether one person is a parent (or to find all grandparents) but also to conclude that if you know someone is a grandparent, and they are the parent of some one, then that person is someone's parent.
Debugging rarely works correctly between languages, and features like "find all references" usually break too. Maybe that's not an issue with Prolog because a C logic solver would also be hard to debug, but it's a problem with many template languages.
>The nice thing about prolog is that you write logical rules, and they can get used in whatever order and direction that is needed.
This generalizes!
Prolog: declare relations. Engine figures out how to satisfy them. Bidirectional -- same rules answer "is X a grandparent?" and "find all grandparents."
LLMs do something similar but fuzzier. Declare intent. Model figures out how to satisfy it. No parse -> AST -> evaluate. Just: understand, act.
@tannhaeuser is right that Prolog's power comes from what the engine does -- variables that "range over potential values," WAM optimization, automatic pruning. You can't get that from a library bolted onto an imperative language. The execution model is different.
Same argument applies to LLMs. You can't library your way into semantic understanding. The model IS the execution model. Skills aren't code the LLM runs -- they're context that shapes how it thinks.
Prolog showed that declarative beats imperative for problems where you can formalize the rules. LLMs extend that to problems where you can't.
I've been playing with and testing this: Directories of YAML files as a world model -- The Sims meets TinyMUD -- with the LLM as the inference engine. Seven architectural extensions to Anthropic Skills. 50+ skills. 33 turns of a card game, 10 characters, one LLM call. No round trips. It just works.
The syntax of Prolog is basically a subset of the language of First Order Logic (sans quantifiers and function symbols), it doesn't get any more minimal than that. What's special in Prolog compared to imperative languages including functional languages is that variables aren't "assigned" but implicitly range over potential values until satisfying the context, like in math formulas for sets. Yes you can express that awkwardly with tons of type annotations and DSL conventions so that you never have to leave your favourite programming language. But then there's the problem of a Prolog "engine" doing quite a bit more than what could be reasonably assumed behind a synchronous library call, such as working with a compact solution space representation and/or value factoring, parallel execution environment, automatic value pruning and propagation, etc.
The integration of a Prolog backend into a mainstream stack is typically achieved via Prolog code generation (and also code generation via LLMs) or as a "service" on the Prolog side, considering Prolog also has excellent support for parsing DSLs or request/responses of any type; as in, you can implement a JSON parser in a single line of code actually.
As they say, if Prolog fits your application, it fits really well, like with planning, constraint solving, theorem proving, verification/combinatoric test case enumeration, pricing models, legal/strategic case differentiation, complex configuration and the like, the latter merely leveraging the modularity of logic clauses in composing complex programs using independent units.
So I don't know how much you've worked hands on with Prolog, but I think you actually managed to pick about one of the worst rather than best examples ;)
> So I don't know how much you've worked hands on with Prolog, but I think you actually managed to pick about one of the worst rather than best examples ;)
Seems more like an interesting research project than something I'd ever deploy in an application serving millions of users
I can't speak to any sort of scalability but I can definitely say that not everything needs to be built for millions of users. There's plenty of utility in tools you use to help even a single person (even yourself!)
Typically, what's nicer is the absence of other features that interfere with the important ones.
For example, Prolog isn't a general purpose functional or imperative language: you can assert, retract and query facts in the automatically managed database, risking only incorrect formulas, inefficiencies and non-monotonicity accidents, but not express functions, types, loops, etc. which could have far more general bugs.
I like how classes escape closures but then dependency injection frameworks have to work around that because now it is hard to think of construction as passing arguments to functions in the correct order.
I am so glad LLMs eliminate all of that and just call functions in the right order.
No, LLMs like NextJS style injection as much as anyone.
There is nothing magical about topological sort and calling constructors in the right order, which is all DI is.
I dislike it a lot, it is exactly like any other construct that allows you to throw code at anything in a way that sucks (Haskell lens, optics, monad transformers).
It allows people to granularize the whole codebase to the point where you can’t do much about it. For most, they should just stick with functions, no one can build 100 levels deep function callstacks without it being cumbersome, but DI makes it a breeze.
I fell out of love with Java not because of the language, but because it got tied up with DI. Don't get me wrong, the allure of DI is really neat. Make all sort of interfaces and just call the function and it can be implemented by dozens of things. Perfect for a lot of use-cases. But then reality hits, and you eventually realize how complex the entire codebase is because it's pattern 1, pattern 2, p3, p4, etc... People are so obsessed with GoF patterns that they're not getting anything done other than spending the first month on a beautiful API.
Then I got into Python and people were building useful server APIs in a day.
Both have their place, but I think the problem with the first route is that EVERYTHING ends up with Spring or CDI and complexity overload even if only 1 thing will ever be "implemented".
> There is nothing magical about topological sort and calling constructors in the right order, which is all DI is.
Lol... That's exactly the kind of thing we call "magic" in software development.
Anyway, if your framework is entirely based on DI, everybody that uses the framework will use DI, and the LLMs will generate code for it that uses DI. That does not contest my point in any way.
Absolutely. In the same direction as some people I've heard along the lines of "Anything you can do with language X, can be done with assembler, just have some routines for that in your stash"
The only languages I know that can do prolog-like-constructs as-a-library are lisps, or at least langs that have reasonable symbol constructs. Usability is way way worse if you can’t talk about variables as first class objects.
I was talking to Bob Harper about this specific issue (context was why macro systems are important to me) and his answer was “you can just write a separate programming language”. Which I get.
But all of this is just to say that doing relational-programming-as-a-library has a ton of issues unless your language supports certain things.
I believe Rust uses datafrog, Datalog as a library to implement some of its next gen solvers for traits and lifetimes. Not a lisp and maybe this still isn’t as elegant as you had in mind? Curious how this library compares for you.
If you want to see what it looks like when you actually embed Datalog in your language, have a look at Flix: https://flix.dev/
(Select the "Usinag Datalog..." example in the code sample dropdown)
The Rust code looks completely "procedural"... it's like building a DOM document using `node.addElement(...)` instead of, say, writing HTML. People universally prefer the declarative alternative given the choice.
The experimental "Polonius" borrow checker was first implemented with datafrog, but I believe it's been abandoned in favour of a revised (also "Polonius") datalog-less algorithm.
Yea I’ve wanted to try using logict to do some larger logic programming stuff. I’ve done it with list monad but found a lot of speed issues, never quite figured out why it was so slow.
Speaking of prolog, any recommendations for resources learning it at a stage somewhere between "draw three circles" and "draw the rest of the owl"
I don't have real work I need prolog for, but I find it an interesting subject, My personal learning goal, the point where I can say I know prolog reasonably well is when I can get it to solve this mit puzzle I found, a sort of variant of soduku. I found a clever prolog solver for soduku that I thought could teach me more in this domain, but it was almost to clever, super optimized for soduku(it exploited geometric features to build it's relationships) and I was still left with no idea on how to build the more generic relationships I need for my puzzle(specific example if soduku cells were not in a grid how could they be specified?), in fact I can find very little information on how to specify moderately complex, ad hoc relationships. One that particularly flummoxed me was that some rules(but you don't know which) are wrong.
Prolog is great because when it works it feels like magic. You give it some pragmas and it tells you the answer. The downside is when it doesn't work it also feels like magic. It's not easy to reason about the amount of work it needs to do. If your Prolog program is taking a long time to run it is hard to figure out if it is going to take 2 hours or 4,000 millennia.
Disclaimer: I've no idea what I'm talking about. :)
But I have heard repeatedly that the good thing of prolog is the compiler, that takes information and queries that would be awful inefficient, and convert them in something that actually works. So I'm not sure... of course, you can convert virtually any language in a kind of library with some API that basically accepts source code... but I'm pretty sure is not what you meant.
I think the examples others have highlighted show the problem with just making it a library. They’re all lacking a lot of features from Prolog, particularly in terms of optimization. Just use Prolog if you need its features and invoke SWI-Prolog like you’d call any other language’s interpreter.
As an example of a use case, "Gerrit Code Review"[1] is written in Java and uses prolog for the submit rules.[2]
I haven't looked into the implementation. But taking a brief glance now, it looks interesting. They appear to be translating Prolog to Java via a WAM representation[3]. The compiler (prolog-cafe) is written in prolog and bootstrapped into Java via swi-prolog.
I don't know why compilation is necessary, it seems like an interpreter would be fast enough for that use case, but I'd love to take it apart and see how it works.
Embedded DSLs are libraries. They are the epitome of the advice to write a library. It just so happens that the library abstractions could map to a language if you wanted to add parsing and all of the other machinery.
References were Racket with the Racklog library¹. There's also Datalog² and MiniKanren, picat, flix. There were tons of good comments there which you should check out, but PySwip seemed like "the right thing" when I was looking at it: https://github.com/yuce/pyswip/
...documentation is extremely sparse, and assumes you already know prolog, but here's a slightly better example of kindof the utility of it:
# ya don't really care how this works
prolog.consult("diabetes_risk.pl")
# ...but you can query into it!
query = "at_risk_for_diabetes(Person)"
results = list(prolog.query(query))
...the point being there's sometimes some sort of "logic calculation that you wish could be some sort of regex", and I always think of prolog as "regexes for logic".
One time I wished I could use prolog was trying to figure the best match between video file, format, bitrate, browser, playback plugin... or if you've seen https://pcpartpicker.com/list/ ...being able to "just" encode all the constraints, and say something like:
...this is a terribly syntactically incorrect example, but you could imagine that this would be horrific code to maintain in python (and sqrt(horrific) to maintain in prolog), but _that's_ the benefit! You can take a well-defined portion and kindof sqrt(...) the maintenance cost, at the expense of 1.5x'ing the number of programming languages you need to expect people to know.
Think of Prolog the language as just a serialization of a Prolog AST. The AST could be constructed in any programming language as a library. But what if we want to share and store these ASTs? We can serialize them to Prolog the language! The language has value even if it’s a library.
Prolog admittedly mystifies me even more than the Haskell family. How do you do anything effectful, like read from a file, or output arbitrary data to standard out, or set up a loop to process keyboard events every 1/n seconds? How do you make system calls?
Prolog is a contrived example. It's small and simple enough to be implemented as a DSL embedded in another language, reusing most of the parser and leaningn its execution logic.
Now try to produce a library that adds compile-time features: static types, lifetimes, the notion of const and constexpr, etc. You can, of course, write external tools like mypy, or use some limited mechanism like Java annotations. But you have a really hard time implementing that in an ergonomic way (unless your language is its own metalanguage, like Lisp or Forth, and even then).
Creating a library that alters the way the runtime works, e.g. adding async, is not entirely impossible, but usually involves some surgery (see Python Twisted, or various C async libs) that results in a number of surprising footguns to avoid.
Frankly, even adding something by altering a language, but not reworking it enough to make the new feature cohesive, results in footguns that the source language did not have. See C#'s LINQ and exceptions.
But why should it be though? You haven’t really addressed that. It’s like saying “Haskell shouldn’t be its own language, it should just be a couple of features like lambdas integrated into a JavaScript library”. Well if you do that you get some nice features in JavaScript but you’ve done away with the whole value proposition of pure functional programming. That’s an actual loss, there’s something to be said for maintaining a pure set of features that gives languages different properties and guarantees you can’t get with “everything is just a lib to an imperative language”
Pure functional programming and lazy evaluation.. sure, you could create classes and a meta-function that selectively eval's thunks at a time, but the call site of that kind of library would look atrocious..
You might be able to hack on some of the datatype semantics into JS prototype-based inheritance (I'd rather start with TypeScript at that point, but then we're back at the "why isn't it a library" debate) to keep those ontologies from being semantically separate, but that's an uphill battle with some of JS's implicit value conversions.
I consider Logic Programming languages to be the go-to counterargument to TFA but yeah, anything with lazy eval and a mature type system are strong counterexamples too.
I was big fan of Scala a decade ago. The idea of a “scalable language” where DSLs could be built within the type system seemed super powerful. I lost my enthusiasm when the community decided they wanted to use it as Haskell on the JVM.
I’m hoping more recent developments, like WASM or Graal, provide a route for more flexibility when selecting languages. It’s nice to see Rust slowly become a serious choice for web development. Most of the time JS is fine, but it’s good to have the option to pull out a stricter low-level language when needed.
That's the main issue I found with Scala, and as I grow older also with certain libraries (especially in unit testing land) that try to add a language / DSL on top. Not only do you need to learn Scala, you need to learn various DSLs on top of that depending on what you use or want to achieve. Some egregious examples here and there.
I'm sure there's good use cases for it - one impressive example at the time was using functional programming to create Hadoop map / reduce jobs, a oneliner in Scala was five different files / classes in Java. But for most programming tasks it's overkill.
You can write boring code in Scala, but in my (limited) experience, Scala developers don't want to write boring code. They picked Scala not because it was the best tool for the job, but because they were bored and wanted to flex their skills. Disregarding the other 95% of programmers that would have to work with it.
(And since these were consultants, they left within a year to become CTOs and the like and ten years on the companies they sold Scala to are still dealing with the fallout)
> Not only do you need to learn Scala, you need to learn various DSLs on top of that depending on what you use or want to achieve
That is AFAIK the "curse of lisp" because is so easy (and needed and encouraged) to write SDLs, any ecosystem grows many languages in a hurry, so suddenly that elegant minimalistic beautiful pure language, becomes 1000 beautiful clean languages. Now you have to learn them all...
> You can write boring code in Scala, but in my (limited) experience, Scala developers don't want to write boring code. They picked Scala not because it was the best tool for the job, but because they were bored and wanted to flex their skills. Disregarding the other 95% of programmers that would have to work with it.
Intersting observation.
So basically Scala is to the JVM what Perl is to scripting?
You can write readable Scala code, just like you can write readable Perl code. But both languages allow you to to write very concise and cryptic code as well.
Scala doesn't seem to optimize for the "one obvious solution" approach like Python does. Scala seems to be more TIMTOWDY like Perl.
Scala was designed from the beginning to support classical Java-style OOP code and also Haskell-like functional code. These are 2 very different styles in one language. And then Scala supports defining DSLs which give you even more flexibility.
You can write boring code in Scala, but in my (limited) experience, Scala developers don't want to write boring code.
Guilty as charged!
> They picked Scala not because it was the best tool for the job, but because they were bored and wanted to flex their skills.
Guilty as charged!
> Disregarding the other 95% of programmers that would have to work with it.
No. Your coworkers end up being the other 5% of programmers that have the same taste as you. Interviewers ask about monads and lenses. It's fine, as long as everyone is on the same page. Which... they kind of have to be.
> I lost my enthusiasm when the community decided they wanted to use it as Haskell on the JVM
It's not the whole community, not by a long shot. Don't judge Scala by the Scala subreddit.
Most new things you'll see written about Scala are about solving difficult problems with types, because those problems are inexhaustible and some people enjoy them, for one reason or another. Honestly I think this shows how easy and ergonomic everything else is with Scala, that the difficulties people write about are all about deep type magic and how to handle errors in monadic code. You can always avoid that stuff when it isn't worth it to you.
The type poindexters will tell you that you're giving up all the benefit of Scala the moment you accept any impurity or step back from the challenge of solving everything with types, and you might as well write Java instead, but they're just being jerks and gatekeepers. Scala is a wonderful language, and Scala-as-a-better-Java is a huge step up from Java for writing simple and readable code. It lets you enjoy the lowest hanging fruit of functional programming, the cases where simple functional code outshines OO-heavy imperative code, in a way that Java doesn't and probably never will.
Haskell is usually used as a DSL. I believe Haxl is used at Meta and TidalCycles is a good example of another DSL built in Haskell.
Although I agree the usual lens, optics, machines, pipes or other higher kinded libs are completely unnecessary, solving problems you do not want to have and have dire performance implications, but are at least correct and allow you to throw code at problems quickly, even though that code sucks in all ways except correctness.
I don’t agree that pipes should be in your list, at least for some use cases. Streaming data through pipes gives capabilities that systems written in more traditional ways often simply don’t match. Look at the use of the Stream API in Java for an example of the utility of this outside of the Haskell context.
Pipes also don’t necessarily have “dire performance implications”, but it depends a lot on the implementation. Haskell libraries don’t always emphasize real world performance as a top criterion. E.g. see https://github.com/composewell/streaming-benchmarks for some truly wild variations in performance across libraries (disclaimer: I haven’t investigated or verified those numbers.)
Have you tried Clojure(Script)? It could be just what you need, bottom-up programming in a Lisp-like language essentally means extending the langauge in order to solve the problem at hand.
Or, as Paul Grahmam put it in his 1993 book On Lisp:
"a bottom-up style in which a program is written as a series of layers, each one
acting as a sort of programming language for the one above"
I recently started to learn Scala and I love it, also for it's functional aspect.
Regarding your comment, it feels like scala is generic enough to be used also in other ways, and definitively for DSLs. What do you think it's missing?
I think the GP is thinking about how libraries and ecosystems are often more important than the language. Most emphasis in scales is in a collection of competing frameworks that, today, are very FP oriented. Some hide the category theory while others put it up front, but it's ultimately what you do. The libraries that wanted to do imperative OO lost most support.
Also see, for instance, Java. There's Java, the language that keeps improving, and then the Spring ecosystem, which is what 95% of programmers end up having to use professionally, with its heavy "magic" component. Writing services avoiding Spring is going against the grain. It might as well be part of the language as far professional Java use is concerned.
Communities matter more than the language features, and Java is all Spring, and now Scala is really a choice of Zio and Cats
Hopefully project Panama will see better interoperability with libraries using the C memory model however migration does not appear to be easy. Arrow Java still uses sun.misc.Unsafe for native memory access.
Doing fancy things with types used to interest me, now it's the last thing I want to touch, after being burned too many times by libs trying to be clever.
I used Scala a few times when it was semi popular, just seemed like Java but with lots of redundant features added. Not sure what the aim was.
Certainly one can get too clever/fancy, but I appreciated that Scala let me express things in the type system that made more of my program confidently correct at compile time than I could do in Java. I hate writing tests, and with Scala, I could write fewer of them, but still be confident that things were working as intended.
But ultimately using Scala at the place I worked at the time was a failure. A couple of my co-workers had introduced it, and I joined the bandwagon at some point, but it just didn't work out.
Many Java developers inside the company didn't want to learn, and it was really hard to hire good Scala developers. The ones who did learn (myself included) wrote terrible Scala for a least the first 6 months, and that technical debt lingered for a long time. When other people outside the team (who didn't know Scala) needed to make changes to our code, they had a lot of trouble figuring things out, and even when they could, the code they wrote was -- quite understandably -- bad, creating extra work for us to review it and get it into shape.
I also feel like Scala suffers from similar complexity/ways-to-do-things problems as C++. I often hear people say things like "C++ can be a safe, consistent language if you just use a subset of it!", and then of course everyone has a subtly (or not-so-subtly) different subset that they consider as The One True Subset. With Scala, you can write some very complex, type-heavy code that's incredibly hard to read if you are not well-versed in type/category/etc. theory (especially if you are using a library like cats or scalaz). Sure, you could perhaps try to come up with some rules around what things are acceptable and what aren't, but I think in this case it's a hard thing to specify, and different people will naturally disagree on what should be allowed.
I really wanted Scala to succeed at our company, but I think that's hard to do. I feel like the ideal case is a small company with just a few tens of developers, all whom were hired specifically for their Scala expertise, with a product/business that is going to keep the number-of-developers requirement roughly static. But that's probably very rare.
i mean, it follows the java philosophy (preseving backward compat). theyve done great work improving java. but i see no reason to use it over scala where i get better features, its more like a java 2.0
Then don't. You can use Scala to your heart's content. No one is stopping you.
I had to work on a Scala codebase at some point, and I thought it horrible. I judge a language on how easy it allows you to create an unreadable mess. Scala makes it incredibly easy. And the people that enjoy Scala seem to like "unreadable messiness" as a feature.
I found it fun to learn the basics, and it was interesting to think of problems from a FP approach, but it is never something I would use in the real world.
I vastly prefer Java. The features it imported from Scala were fine, made the language better. It doesn't need to import everything.
In pretty common applications, virtual threads will make the difference between chaining futures (this.then(that).then(...)) vs not, all throughout your code. Or some frameworks had far uglier ways to deal with cooperative multitasking.
Lambdas weren't simple to shoehorn into Java. But most of the recent changes have been implemented as well or better, or as well as you could imagine while maintaining backwards compatibility and Java-ness.
Records/sealed interfaces (ADTs) are quite clean.
Text Blocks are better in Java IMO. The margin junk in Scala is silly.
Scala is a fantastic language and in fact I'd say it's the language that proves the article wrong.
Java was the language where "write libraries instead" happened, and it became an absolute burden. So many ugly libraries, frameworks and patterns built to overcome the limitations of a simple language.
Scala unified the tried-and-tested design patterns and library features used in the Java ecosystem into the core of its language, and we're better off for it.
In Java we needed Spring (urghh) for dependency injection. In Scala we have the "given" keyword.
In Java we needed Guava to do anything interesting with functional programming. FP features were slowly added to the Java core, but the power and expressivity of Java FP is woeful compared what's available at the core of Scala and its collections libraries.
In Java we needed Lombok and builder patterns. In Scala we have case classes, named and default parameters and immutability by default.
In the Java ecosystem, optionality comes through a mixture of nulls (yuck) and the crude and inconsistently-used "Optional". In Scala, Option is in the core, and composes naturally.
In Java, checked exceptions infect method signatures. In Scala we have Try, Either and Validated. Errors are values. It's so much more composable.
There's so much more - but hopefully I've made the point that there's a legitimate benefit in taking the best from a mature ecosystem and simple language like Java and creating a new, more elegant and complete language like Scala.
I think you misunderstood the article (or only read the first couple paragraphs). The author sets the stage with the statement in the article title (a quote heard from other people), but shows that those fancy language features in some languages are exactly why rich, easy-to-use libraries can be built. And that some of these rich, easy-to-use libraries simply cannot be built in some languages that lack those features.
I would love to have a scripting language has typed features and you can replace bash with.
What comes close is:
#! /usr/bin/env elixir
Mix.install([:jason])
defmodule JsonPrettyPrinter do
def get_stdin_data do
:stdio
|> IO.read(:all)
|> Jason.decode()
|> case do
{:ok, json_data} -> json_data
_ -> raise "Invalid JSON payload was provided"
end
end
end
JsonPrettyPrinter.get_stdin_data()
|> JsonPrettyPrinter.pretty_print_json()
|> IO.puts()
(drops your size formatting, so not strictly equivalent)
Which isn't meant to "compete" - nushell looks nice -, but to show that the lower-threshold option for those of us who don't want to switch shells is to throw together a few helpers in a language... (you can get much closer to your example with another helper or two and a few more "evil" abuses of Ruby's darker corners, but I'm not sure it'd be worth it; I might a wrapper for the above in my bin/ though)
This example shows nicely how ugly text processing is: you have to use head and tail simply to trim out the first line of ls (the total).
I think it doesn't even work correctly. ls lists files and directories and then picks the first 4 (it should only select files).
And this also uses awk and jq, which are not just simple "one purpose" tools, but pretty much complete programming languages. jq is not even part of most standard installations, it has to be installed first.
> And this also uses awk and jq, which are not just simple "one purpose" tools, but pretty much complete programming languages
In a way that exactly illustrates the GGP's point: why learn a new language (nushell's) when you can learn awk or jq, which are arguably more generally- and widely-applicable than nushell. Or if awk and jq are too esoteric, you could even pipe the output of `find` into the python or ruby interpreters (one of which you may already know, and are much more generally applicable than nushell, awk, or jq), with a short in-line script on the command line.
> awk or jq, which are arguably more generally- and widely-applicable than nushell
That is backwards. I know I said "complete programming languages", but to be fair, awk only shines when it comes to "records processing", jq only shines for JSON processing. nushell is more like a general scripting language — much more flexible.
I'd replace the first part with (which isn't any shorter, but in general if I want a list of files for a pipeline, find is usually more flexible than ls for anything but the most trivial):
find -maxdepth 1 -type f -printf '%s %f\n' | sort -n | head -n 5
For the latter part, I'd tend to think that if you're going to use awk and jq, you might as well use Ruby.
("-nae" effectively takes an expression on the command line (-e), wraps it in "while gets; ... end" (-a), and adds the equivalent to "$F = $_.split" before the first line of your expression (-n))
It's still ugly, so no competition for nushell still.
I'd be inclined to drop a little wrapper in my bin with a few lines of helpers (see my other comment) and do all Ruy if I wanted to get closer without having to change shells...
It's close, but there are some things that could be better to make it easier to access e.g. file size and type. I think maybe a 50-100 line set of helpers and a one line wrapper (to spawn Ruby with -r<helper> -e <command line>) would get you mostly to where nushell is.
Unfortunately, I don't think Nushell brings much benefit for folks who already know Bash enough to change directories and launch executables and who already know Python enough to use more complicated data structures/control flow/IDE features
I'm still rooting for Nushell as I think its a really cool idea.
For me the blocker was having to switch to bash/powershell when moving to a different machine (ie: servers, work machine, etc..). I would end up needing to redo same things to be compatible with the existing tools; eventually I just gave up and got used to readily available shells instead.
Ok if it's not for you. But there is of course a very good reason — work with objects in the pipeline instead of "dumb text". Also PowerShell and nushell are quite nice to learn, whereas Bash is absolutely horrible.
I wonder if this is a case of "worse is better", or just the long-term entrenchment of text. Because nushell hasn't been adopted all that much compared to bash or even zsh (or a "real" scripting language like python or ruby). I don't know much about PowerShell adoption (haven't used Windows in over 20 years), but I'd assume since it's a first-party system that's default installed(?), it's done better adoption-wise.
I agree that bash sucks, but I really have no motivation to learn something like nushell. I can get by with bash for simpler things, and when I get frustrated with bash, I switch to python, which is default-available everywhere I personally need it to be.
Back to text, though... I'm honestly not sure objects are strictly better than dumb text. Objects means higher cognitive overhead; text is... well, text. You can see it right there in front of you, count lines and characters, see its delimiters and structure, and come up with code to manipulate it. And, again, if I need objects, I have python.
I get the point of "either Bash or straight to a real programming language". That's what I do too, for automation. I like how PowerShell makes one-off tasks easier which would otherwise be the typical pipe of cat, grep, sed, awk etc.
Well, the reason is you can stop using Bash. If you never write Bash scripts already then you probably don't need it (and also congratulations on doing things right), but most people at least have lazy colleagues that write shell scripts. One day I'd like them to be not awful.
The naming convention is `verb-noun`. It's convenient for discoverability and consistency. The short commands are aliases.
The last command is properly cased, because I pressed tab (it auto-completes and fixes the case). The other commands I typed without tab completion. You can write however you want, PS is not case sensitive.
For me the best benefit of nushell is not the easier syntax, but the static type checks. It catches most typos before running the script, which is a godsend when the script is slow and/or has destructive operations.
OCaml is a scripting language in this sense. No need to compile an executable ahead of time, just have a `#!/usr/bin/env ocaml` shebang (or more realistically: `#!/usr/bin/env -S ocaml -I +unix unix.cma`) at the top of a source file.
Though, I don't think it has the capability for single-file scripts to declare 3rd-party dependencies to be automatically installed.
I am unhappy with python. It degrades fast. It deprecates libraries every minor release and that tends to break the applications I use. Recent examples are distutils and opsaudio.
For everyday scripting -- the types of things where I'd be writing in bash but get frustrated with it and switch to python -- I nearly always only need what's in the stdlib.
Sure, for "applications", the ecosystem can be frustrating at times, but I don't think that's what we're talking about here.
Doesn't help much because even the standard library bitrots after enough Python releases. I have things I write today but can't run on a NAS that has older Python. No issues like that with Powershell for example.
I dunno what issues you are running into, but generally, code from old Python should work fine under new releases if you are developing, you just have to set up your venv right up front and install the specific version of libraries that don't have modern Python code.
I still work on projects that were written under 3.6.
If you care enough, you can also use something like asdf to install an older Python alongside the system one.
Python is actually kind of awkward for this use case since you can't import from other files easily unless you are in a proper Python package, which isn't usually the case for everyday scripting.
No it doesn't. You can't do something like `import ../../foo/bar`. You can mess around with PYTHONPATH and importlib to work around that but that's a horrible hack that also breaks all tooling. Not a good idea.
With Deno you can just import by relative file path and it just works like you'd expect and the tools support it. I wish more languages worked like that.
>You can mess around with PYTHONPATH and importlib to work around that but that's a horrible hack that also breaks all tooling
....no.
import keyword uses importlib under the hood. It just does a lot of things for you like setting up namespace. But importlib has all the functionality to add the code in any python file cleanly.
My custom agent that I use basically has the functionality to wrap every piece of code it writes as a tool and stores it into python files. During tool calls, it pretty much dynamically imports that code as part of a module within the project. Works perfectly fine.
Common misconception. That doesn't import by relative file path; it imports by relative package path. It's actually quite different. Scripts you run directly aren't in a package so you can't use it at all. You can go above the package root. Namespace packages mean it can jump to other directories.
Everyone wants that to just mean "import relative to this file" but it doesn't.
you won't believe how powerful Python is with libraries. ChatGPT and Claude made a brand new browser, that isn't based on Chromium or Firefox, and yet still follows many aspects of layout correctly. I read the article we're discussing ("stop designing languages") on this browser and I'm currently using it to post this reply.
it doesn't look like it would be easily derived from Chromium or Firefox, because this code is Python and those don't use Python this way.
By the way is there any feature you'd like to see added to the toy browser? The goal is that one day it's a replacement for Chrome, Firefox, etc. It's being built by ChatGPT and Claude at the moment. Let me know if there are any feature ideas you have that would be cool to add.
>A python-based browser? What are you using for the GUI toolkit?
Great questions.
1. Yes, for the moment. Like the title of this article suggests - we're using a library! :)
It's great to iterate in Python, which has a large ecosystem of libraries. Believe it or not, there is a chance that in the future it would be able to translate the language into a different one (for example, C++) while using C++ bindings for the same gui libraries. This would speed up its actions by 40x. However, not all of the libraries used have C++ bindings so it could be harder than it looks.
you can have a quick read through. Originally it was using tkinter for the GUI toolkit. I believe it is still using tkinter, but the AI might be leaning on some other library. As you read it, is it using anything but tkinter for the GUI toolkit?
These libraries are doing a lot of heavy lifting, but I think it is still ending up drawing in tkinter (not handing off rendering to any other library.)
If you just wait a few months, then that program will be written in a typed language. The type checker for Elixir is coming along nicely and every release brings more checks.
Babashka (https://babashka.org/) is an interesting tool for scripting. It's Clojure, so dynamic typing, but it's data orientation makes it a great fit for something like your example.
I wanted to say Haskell with shh[^1] and stack's or nix's shebangs[^2][^3], but interpreted haskell is not particularly fast.
Also I think a Python script is reasonable if you use a type-checker with full type annotations, although they are not a silver bullet. For most scripts I use fish, which is my preferred interactive shell too.
[3]: https://wiki.nixos.org/wiki/Nix-shell_shebang. On a side note, if you were to use nix's shebang for haskell scripts with dependencies, you should be using https://github.com/tomberek/- instead of impure inputs, because it allows for cached evaluation. I personally cloned the repo to my personal gitlab account, since it's small and should never change
@dev_l1x_be: The answer isn't a new typed scripting language. It's recognizing what the interpreter already is.
LLMs are eval(). Skills are programs. YAML is the motherboard.
@unkulunkulu nails it -- "library as the final language", languages all the way down. Exactly. Skills ARE languages. They teach the interpreter what to understand. When the interpreter understands intent, the distinction dissolves.
@conartist6: "DSL is fuzzy... languages and libraries don't have to be opposing" -- yes. Traditional DSL: parse -> AST -> evaluate. LLM "DSL": read intent -> understand -> act. All one step. You can code-switch mid-sentence and it doesn't care.
The problem with opinionated frameworks like ROR and their BDFLs like DHH is that one opinion is the WRONG number!
The key insight nobody's mentioned: SPEED OF LIGHT vs CARRIER PIGEON.
Carrier pigeon: call LLM, get response, parse it, call LLM again, repeat. Slow. Noisy. Every round-trip destroys precision through tokenization.
Speed of light: ONE call. I ran 33 turns of Stoner Fluxx -- 10 characters, many opinions, game state, hands, rules, dialogue, jokes -- in a single LLM invocation. The LLM simulates internally at the speed of thought. No serialization overhead. No context-destroying round trips.
@jakkos, @PaulHoule: nushell and Python are fine. But you're still writing syntax for a parser. What if you wrote intent for an understander?
Bash is a tragedy -- quoting footguns, jq gymnastics, write-only syntax. Our pattern: write intent in YAML, let the LLM "uplift" to clean Python when you need real code.
Postel's Law as type system: liberal in what you accept. Semantic understanding catches nonsense because it knows what you MEANT, not just what you TYPED.
That's a trite, low effort, worthless, content free comment, which totally misses the point and fails to engage. You haven't made any other comments contributing to this discussion, except that one shallow drive by complaint. If you're going to whine about using llms as a shell, then at least try to do better than an llm or redditor yourself.
So do you disagree with any of my points, or my direct replies to other people's points, or is that all you can think of to say, instead of engaging?
Do you prefer to use bash directly? Why? If not, then what is your alternative?
What do you think of Anthropic Skills? Have you used or made any yourself, or can you suggest any improvements? I've created 50+ skills, and I've suggested, implemented, and tested seven architectural extensions -- do you have any criticism of those?
Obviously you use llms yourself, so you're not a complete luddite, and you must have some deeper more substantial understanding and criticism than those two words from your own experience.
How do your own ideas that you blogged about in "My LLM System Prompt" compare to my ideas and experience, in your own "professional, no bullshit, scientific" opinion?
Your entire blog post on LLM prompts is "I don't like verbiage" in five sentences. Ironic, then, that your entire contribution here is two empty words. I made specific technical points, replied to real people, linked proof. 'Slop' is the new 'TL;DR' -- a confession of laziness dressed as critique. Calling substance slop while contributing nothing? That's actual slop.
This looks to me like partly a false dichotomy. We can design languages and write libraries. Some would even argue that some kinds of "libraries" could be viewed as languages themselves, as much as some languages might as well have been written as libraries in another language.
Also often, the language doesn't live isolated from its implementation (compiler or interpreter). While theory looks at languages via its semantics, in practice as the OP notes it is about the quality of the implementation and what can be reasonably done with the language.
A recent [1] case is Julia. I think it has hit a kind of sweet spot for language design where new performant code tends to get written in Julia rather than in some other language and bound to it. At its core, it is a simple "call functions, passing data in and getting results out" kind of language, but what the functions ("methods") mean and how the compiler does just-ahead-of-time compilation with deep type specialized code means you can write high level code that optimizes very well. Those mechanics operate under the hood though, which makes for a pleasant programming experience ... and there are loads of cutting edge packages being written in Julia. It is less interesting to look at Julia as "just the language".
[1] recent in programming languages is perhaps anything <= 15 years? .. because it takes time to discover a language's potential.
Well, maybe. The problem is that mature languages and ecosystems are mature and new features have to be shoehorned in. Raku (https://raku.org) on the other hand is intentionally designed as a braid of sub languages (slangs) for quoting, regex, PEG, etc and you can easily make your own slang with eg. https://raku.land/zef:lizmat/Slangify so you get your DSL as a drop down language in a general PL setting.
I would go so far as to say the rise of Rails and the downfall of J2EE being concurrent was not entirely accidental. I have/had no particular affiliation for Rails, but it demonstrated how to write simple, opinionated backend code, and that inspired a flurry of Java/JVM web frameworks that tried to follow a similar pattern and eventually gave us libraries like DropWizard, Javalin, SparkJava, even Spring Boot to some extent.
One side of my brain agrees that's a dumb way to judge anyone but then when I think about the accepted filtering mechanism they really aren't any better or any worse. You cannot interview everyone and ultimately you're looking for some combination of competence, alignment, drive and social fit. Filtering on where you worked previously or where you went to school or whether you can pass some coding challenge only partially fills in the matrix. And the size and shape of the organization can drive how much people in the hiring loop look at each data point. This senior engineer's ideal for alignment and social fit probably favored people who think like them or their department's head.
To be fair, years ago Rails was what all the "bootcamp" programmer mills were pushing. Only you have the full context, but absent of that it is likely that Rails was truly found to be associated with poor applicants. Not because of anything about Rails itself, but because of those "bootcamps" not developing quality people. The culling has to occur at some point. If you throw some great developers out with the bathwater, so be it. There isn't enough time in the day to worry about them.
Admittedly, Ruby on Rails makes me think "bootcamp" like you said, and I barely even know what it is.
But shouldn't the check just be that the candidate has used more than one different stack? It's pretty hard for anyone with real experience to stick to one, and even if they do, that's not a good sign either. Or are you saying those bootcamp people end up learning another stack but still not being very good?
> But shouldn't the check just be that the candidate has used more than one different stack?
If you had another filtering mechanism, perhaps you could do that. But what other arbitrary, legally acceptable, filter are you going to use to further narrow the search? Can't realistically throw out all the resumes with female-sounding names, for example. What is going to keep you out of trouble is quite limited.
Why not throw out all the "Rails" resumes? If you had all the time in the world you would interview every last person, of course, but in the real world, with real world constraints, you have to pick a few to interview and live with your choice.
To use the internet's favourite analogy: It's like buying a car. Most people would never find it reasonable to test-drive every single one of them. It is just too time consuming to do that. So, instead, one normally looks at signals to try and distill the choice down to a few cars to test drive. You very well might miss out on what is actually your perfect car by doing that, but if you find one that is good enough, who cares?
On the one hand, that obviously filters out many qualified candidates.
On the other, you only have so much time in the day. It'd take me 3-6 months to give phone screens to every resume that comes in the door for any one engineering role, 8x that for a full 4-hour interview. I have to filter through them somehow if it's my job to hire several people in a month.
You'll obviously start with things that are less controversial: Half of resumes are bot-spam in obvious ways [0]. Half of the remainder can easily be tossed in the circular filing bin by not having anything at all in their resume even remotely related to the core job functions [1].
You're still left with a lot of resumes, more than you're able to phone screen. What do you choose to screen on?
- "Good" schools? I personally see far too much variance in performance to want to use this as a filter, not to mention that you'd be competing even more than normal on salary with FAANG.
- Good grades? This is a better indicator IME for early-career roles, but it's still a fairly weak signal, and you also punish people who had to take time off as a caretaker or who started before they were mature enough or whatever.
- Highest degree attained? I don't know what selection bias causes this since I know a ton of extremely capable PhDs, but if anything I'd just use this to filter out PhDs at the resume screening stage given how many perform poorly in the interviews and then at work if we choose to hire them.
- Gender? Age? ... I know this happens, but please stop.
If there's a strong GitHub profile or something then you can easily pass a person forward to a screen, but it's not fair to just toss the rest of the resumes. They have a list of jobs, skills, and accomplishments, and it's your job to use those as best as possible to figure out if they're likely to come out on top after a round of interviews.
I don't have any comment on rails in particular, but for a low-level ML role there are absolutely skills I don't want to see emphasized too heavily -- not because they're bad, but because there exists some large class of people who have learned those skills and nothing else, and they dominate the candidate pool. I used to give those resumes a chance, and I can't accept 100:1 odds anymore on the phone screen turning into a full interview and hopefully an offer. It's not fair to the candidates, and I don't have time for it either.
And that's ... bad, right? I have some things I do to make it better in some ways (worse in others, but on average trying to save people time and not reject too many qualified candidates) -- pass resumes on to a (brief) written screen instead of outright rejecting them if I think they might have a chance, always give people a phone screen if they write back that I've made a mistake, revisit those filtering rules I've built up from time to time and offer phone screens anwyay, etc -- hiring still sucks on both sides of the fence though.
[0] One of my favorites is when their "experience" includes things like how they've apparently done some hyper-specific task they copy-pasted from the job description (which exists not as a skills requirement but as a description of what their future day-to-day looks like), they did it before we pioneered whatever the tech in question was, they did it at several FAANG companies, and using languages and tools those companies don't use and which didn't exist during their FAANG tenure. Maybe they just used an LLM incorrectly to touch up their resume, but when the only evidence I should interview you is a pack of bold-faced lies I'm not going to give the benefit of the doubt.
[1] And I'm not even talking about requiring specific languages or frameworks, or even having interacted with a database for a database-adjacent role. Those sorts of restrictions can often be too overbearing. Just the basics of "I need you to do complicated math and program some things that won't wake me up at night" and resumes that come in without anything suggesting they've ever done either at any level of proficiency (or even a forward or a cover letter stating why their resume appears bare-bones and they deserve a shot anyway).
Any language/library needs to communicate in two directions: to the machine and to the people. At the micro-level, machines work with bits, or voltages, or whatever. That's a technological problem, not easy, but tractable in a mechanical sense.
People, on the other hand, work with ideas, metaphors, expressions of intent, etc. If a language/library makes the communication of those things easier/better/faster; if it can be "written down" clearly, and "read" clearly by a person, then does it really matter into which taxonomic category it fits? We pick horses for courses. That seems about right.
If Rails works for you, is complementary with what you want to achieve, is an accelerator, and is generally well-understood by the people with whom you work, then use it. Alternatively, if the answer to all the previous is Stanza then go with that. There's less "right" and "wrong" in those decisions than there is "advance", or "struggle". It sounds trite. But, use what works. If something doesn't work make something that does, iff that's the most efficient approach.
For me the title is a bit of a contradiction: I always think about the library as “the final language”.
So author’s example of RoR/Ruby is “RoR is a great web service language that uses Ruby as the base, they evolved together and arguably as RoR is the main source of clients for ruby, ruby was as well designed for RoR as RoR for ruby”
I think about programming/design as languages/translation in a lot of ways: its languages all the way down.
I agree. c# and asp.net core also co-developed. Interestingly in both direction, towards users (tons of type inference, removing boilerplate, ...) and system (writing highly optimized web servers with low level paradigms)
I don't understand, what's Express? As for libraries and Java, I'd argue Java became a well established enterprise language and platform exactly because it makes such highly effective use of libraries.
Javalin was inspired by https://sparkjava.com/ which was inspired by Sinatra (which I think also inspired Express?).
Anyway, libraries like this were only really feasible after Java 8 because of the reliance on lambdas. Having to instantiate anonymous nested classes for every "function" was a total pain before that.
Kinda now that Java has lambdas, but still async in that disn't work as easily as JS, which is important. This is only recently starting to change with Project Loom.
I agree with the sentiment of this article but the question that fascinates me is "when do you need a language feature instead of a library in order to accomplish X, Y, or Z?"
I have to disagree about the author's described purpose of programming languages. PLs exist to provide elegant expression to a curated subset of ways of expressing solutions to problems.
At the extremes, we call these paradigms. Functional languages, Object Oriented languages, Array languages, etc. But every language exists to make some subset of "shapes" of solutions easier to read and write. Elixir encourages you to describe your programs as a distributed system of programs each running a series of transformations to data, thanks to its pipeline system, and to push your branching to function-call level with its pattern-matching multiple dispatch.
Java encourages you to write your application as a collection of things, that know stuff and do stuff, including telling other things to do stuff based on things they know.
C and Go encourage you to write your programs as an ordered series of atomic tasks for the computer to complete.
SQL has you describe what you want your output to look like.
Etc, etc. There are inherent trade offs between languages, because what you make inelegant to express or even inexpressible carries value, too.
There are a few approaches if you want to write a new language. One, as the author argues, is to write a library in an existing language, which may require sacrificing ergonomics to fit inside the syntax of the host language, but is safe, modular and reusable.
Many DSLs can be bolted onto an existing language with support for compiler extensions. This approach offers more flexibility, but often leads to fragmentation and poor interoperability in the language ecosystem.
There is third approach, established by a group in Minnesota [1], which is to design languages and tools which are modular and extensible from the get-go, so that extensions are more interoperable. They do research on how to make this work using attribute grammars.
If the host language has a sufficiently expressive type system, you can often get away with writing a fluent API [2] or type safe embedded DSL. But designing languages and type systems with good support for meta-programming is also an active area of research. [3, 4]
If none of these options work, the last resort is to start from tabula rasa and write your own parser, compiler, and developer tools. This offers the most flexibility, but requires an enormous amount of engineering, and generally is not recommended in 2026.
> If none of these options work, the last resort is to start from tabula rasa and write your own parser, compiler, and developer tools. This offers the most flexibility, but requires an enormous amount of engineering, and generally is not recommended in 2026.
> There is third approach, established by a group in Minnesota [1], which is to design languages and tools which are modular and extensible from the get-go, so that extensions are more interoperable. They do research on how to make this work using attribute grammars.
MLIR [1] has entered the chat :P
I know I know MLIR is an IR and not a programming language, but MLIR does give me the feeling of "an IR to rule them all" (as long as you're ok with SSA representation), and the IR itself is quite high-level to the point it almost feels like an actual programming language, e.g. you can write a MLIR program that compiles to C using the EmitC dialect that feels a lot like writing C.
The author makes a good point about language capabilities enabling certain libraries to be written, just as DSL makes it easier to reason about problems and implement solutions with the right kind of abstractions and language ergonomics (usually at the expense of expressivity and flexibility).
There’s a time in my life where I designed languages and wrote compilers. One type of language I’ve always thought about that could be made more approachable to non technical users is an outline-liked language with English like syntaxes and being a DSL, the shape of the outline would be very much fixed and on a guardrail, and can’t express arbitrary instructions like normal programming languages, but an escape hatch (to more expressive language) for advanced users can be provided. An area where this DSL can be used would be common portal admin app generation and workflow automation.
That said, with the advent of AI assistants, I’m not sure if there is still room for my DSL idea.
As a student of philosophy of language, I obviously agree with the author (against the quoted thesis).
The structure of a language matters to the ease and feel of its use, despite even being logically identical. One parallel would be the syntactic benefits of something like Hintikka’s independence-friendly logic vs first order logic, even if they are equivalent.
The sentiment shared is that we should sacrifice benefits to the next generation to make our own lives easier. This is a common sentiment, but a sad one. The goal should be a natural language based programming language, that everyone can use, along side a technical programming language that makes unambiguous the interface between the language and the machine.
Everyone seems to endorse their happy medium, and those languages are also perfectly fine.
> Can we design a language so expressive that library writers can easily write the most appropriate object system, or most appropriate type system, to fit their application?
The OP's point is well-taken: a new language usually forces you to change 100% of your environment and tooling, whereas a new library respects your habits and preferences.
I follow new language developments with keen interest, but few of them will ever reach the level of maturity to be considered serious candidates for adoption. It's also risky to adopt a language that you cannot easily hire developers for, for example.
Libraries are great, but there is only so much they can address, and that depends on the language, too, as the article correctly points out. And there are two kinds of libries: tool libraries and frameworks. Someone once said it nicely: "Frameworks are like Hollywood - 'You don't call us, we call you!'". Frameworks often require you to submit to their control flow rather the other way round; that's why I prefer tool libraries.
With a Domain Specific Language (DSL), you parse code and build an abstract syntax tree. But you can also build a Python library where you construct the same tree. With the benefit that LLMs are already better trained on Python code. If you need a deterministic programming language, you could use starlark.
DSL is a term with such fuzzy meaning, I don't like it at all. It's always valid to just say "language". Languages and libraries don't even have to be opposing concepts either. Let's say you write the first ever JSON parsing library. Did you just create a library? Or a language?
I have started gathering DSL specific content over on https://reddit.com/r/domainspecificlangs … there are several definitions over there. Personally I would distinguish between a drop down DSL and a full blown independent language.
Logic systems are a good place where the library first approach tends to work well: you keep a small, boring core (the inference engine), and let people extend it with predicates, rules/operators, and domain packages.
I’ve been experimenting with a small defeasible-logic core (argumentation semantics + priorities + conflict detection) that stays stable, while most of the real meaning lives in extension points. https://github.com/canto-lang/canto-lang
Java has Grails web framework. We have designed apps with 75% less resources and time compared to Spring at a big enterprise. But most devs wanted springboot.
Grails requires Groovy, though you can integrate Java classes into a grails app.
Now that we can develop script style with Java 21, I'd like to see something like Grails that worked with Java only...that would be a fun way to develop web apps. I liked Grails, just not Groovy.
> In summary, the purpose of a general-purpose programming language is to enable the creation of powerful and easy-to-use libraries.
Close! The purpose of a general-purpose programming language is to enable the creation of powerful and easy-to-use languages, but often just libraries.
But they are still worse experience that dedicated, separate languages.
Compare ModelingToolkit.jl with Modelica (ok, there are some differences in capacilities, but just compare how better is to express models in Modelica).
> Stanza provides an optional type system, garbage collection, and a multimethod based object system. But if you don't like Stanza's object system, there is no way to write your own. This is one of the main directions of programming language research. Can we design a language so expressive that library writers can easily write the most appropriate object system, or most appropriate type system, to fit their application? Perhaps one day we'll have such a language.
We already have it. It's an obscure little language called C++. Tise interested in those kinds of extensions to a language should look into Herb Sutter's experiments with cppfront: https://hsutter.github.io/cppfront/welcome/overview/
Lisp is what you are after if you want to include some object system as a library, or a new type of switch statement as a library or a new kind of if statement as a library.
C++ can do some of that. Let's say I want an if statement that takes an integer and three blocks of code. It executes the first block if the integer is less than zero, the second if it is zero, and the third if it is positive.
OK, if you squint enough that by "block of code" you mean closure, or function object, then I can write that in C++. I can make the if statement a free-standing function (that is, not a member of a class), and add it to any library I wish.
Now, you can say that it's going to be tedious to use that, because you have to set up three closures every time you want to call this "super if". And you'd be right, but that's a different argument.
One problem is that closures don't actually behave like blocks. Consider that you might want to use this three-legged-if inside a loop. If it's a real statement, then those branches can have `break;` and `continue;` statements which affect the surrounding loop. If those branches are just closures being passed to a function, then they can't.
> OK, if you squint enough that by "block of code" you mean closure, or function object,
But we aren't squinting here; those closures can't perform a return where your `new-if` function is being used, they can't perform a `return` like a proper `if` can, you can't goto, or break or continue.
It's just a function taking functions, with all the restrictions that that entails.
Yes, a function call. Not new syntax. But as a function, it would be trivial to add to a library.
My point was that you can often get the effect you want with no new syntax. (Cue 10,000 replies that state "but you can't get this effect without new syntax!" Perhaps not. Many of those tend to be rather contrived, though. I'm more sympathetic to the argument that new syntax would make something less clumsy. If it's something you need to do a lot, that matters.)
Yes - I see what you mean. There are degrees of ease of use at between - at the extremes - what writing assembly provides, which technically can do it too, and what something like, say, Haskell provides. C++ is of course closer to Haskell than Assembly, but there's still quite a headache in using your solution that is down to absent C++ language features.
You can always use macros! Just look at how beautiful and elegant and easy to learn and transparent to debug the Microsoft C++ MFC COM/OLE/IDispatch/ActiveX object system macrology is. /s
it's strange cause for some devs (lispers, smalltalkers, forth..ists), the language is the core, and any concept is to become a generic linguistic trait (and everything will be build by composing expressions with these traits).
yet at the same time, clojurists love the idea of doing lots of dsl libraries..
Libraries and languages are not actually about syntax or function. They are communities first. They each have a community of users and one of developers. Depending on their application they each attract very different people - which is wonderful.
The work matters too of course. Frequently used functions should be categorically bagged into libs and if the lib is used often enough some of it's functionality should be baked into the language. If languages require something often enough the language layer above should provide it and if things are frequently needed close to the metal it should be baked in hardware. Possibly as a co-processor and then as part of the cpu. We should even have a similar process moving things in the other direction. I cant wait for the day when floating-point arithmetic becomes a library complete with a community of people who still think it's wonderful. Like a football channel to cleanly contain that kind of undesirable materials. Some libraries/modules/frameworks should also be replaced by competent developers. We don't want a leftpad community.
It looks that somebody listened. We now have 3 GTK libraries in a system, a lot of graphics libraries (cairo, etc) 3d libraries (Mesa, vulkan). It is a mess.
Lots of languages could just be implemented with classes in C++. Every "probabilistic language" could just be types that interact with each other properly.
I think I mostly agree with the thesis here, but I actually liked the point in the title at face value, too. We need both, I think. I guess I'll be another annoying Lisp guy, but:
> At this point, the right question to ask would be, well can you write a static-typing library for Scheme that then automatically checks your code for type errors? And the current answer, for now and for the foreseeable future, is no. No mainstream language today allows you to write a library to extend its type system.
The author seems to provide a counter example themselves(?):
> Racket and Shen provide mechanisms for extending their type systems...
I wonder if this is as clear-cut as the author is making it out to be. Coalton, which is effectively a library (and language) for Common Lisp, seems like it basically does this. Maybe that's not exactly what the author is referring to, because it is essentially a new language on top of Lisp using its meta-programming facilities, as opposed to merely extending the type system. Still, it can be used as a library right alongside Lisp code, so I think it's in the same spirit of of the first question of writing a "static-typing library that automatically checks your code" in a dynamic language.
Standard scheme may or may not be able to do this, but most Scheme implementations have unhygienic macros like CL's too, so I'd assume something similar would be possible. The fact that that these tend to be extensions from implementation designers might align with the article's point though. Also somewhat to the author's point, Coalton does rely strongly on CL's underlying type system, for which there's no real equivalent in Scheme. It also relies on implementation-specific optimizations alongside that.
For what it's worth you can (and indeed people have) written object systems in Scheme, despite the language not having one, though they tend not to be performant, which is likely another point towards using/writing a different language. CL also tends to allow fairly deep extension of its object system through the Meta-object Protocol.
I guess my point is that in my (probably biased) opinion, Lisps, or other languages with very strong meta-programming facilities, are pretty close to the language longed for in "Perhaps one day we'll have such a language." They aren't a silver bullet, of course. CL has no easy way to write performant coroutines/continuations, for example, even given all its extensibility. Scheme has no real type system, etc. etc.
I don't think any of this invalidates the articles points, I'm just not sure I agree with the absolutes.
> But thanks to Ruby on Rails, he doesn't have to! So he said that he has no particular opinion about the Ruby programming language, but he absolutely loves Rails.
Ruby got a hype phase with regards to rails. It then dropped. A lot.
TIOBE, while it is in general crap, is somewhat accurate when you plot things over time:
So, ruby peaked with rails between 2006 to 2009 or so, give or take. Then the decline phase set in, and now it is unfortunately also crawling behind perl into extinction. This is very unfortunate - I still use ruby almost daily as the ultimate glue language. But this can not be denied now that ruby is following the extinction path perl already had going some years before.
I was using ruby before rails was created and ruby covers all my web-needs. I had a web-framework in PHP, used it for about three years, ported it into ruby and expanded it massively in the last 20 years or so (well, almost 20 years). I retired from rubygems.org when RubyCentral got crazy in 2024 (and even crazier in 2025 with the mass purge of developers). So, one difference here is that the friend he talks about is using a specific framework. He probably no longer uses ruby nor rails. I use ruby because the language is very well designed and covers (most of my) use cases; the rest I may sprinkle down with java. So whether rails exists or not, makes zero difference to me. Actually without rails it would be better, because people using ruby would be using it because of ... ruby. Even if there are then fewer users. I still think this is better than those who will jump ship anyway because they only use ruby due to rails. These guys are not like in the same boat. They have use cases for getting work done via rails, designing websites, infrastructure related to websites, user-interaction and so forth. But they don't really use ruby as such. Their use case is quite limited. I think this is one of the biggest problems here. It in part explains why ruby dropped down a lot (there are many reasons for this, python being so successful is in my opinion the biggest reason, but the other smaller reasons also add up - that also includes the laughable joke that is documentation in the whole ruby ecosystem. That's inexcusable - note, I am not saying documentation must be perfect, but please look at opal, ruby-wasm or rack - the documentation there is virtually NOT EXISTING.)
> The vast majority of programmers are non-experts, like himself
No, I think he is an expert - just in a specific niche and field. Not all experts know everything equally well.
> Subtle language features like first-class functions, and object systems, are lost on them because they don't really use them anyway.
I don't think this is true. Some language features are very useful. Ruby's blocks for instance. They are probably one of the top three win-win features ruby offers.
> Computer scientists should really be spending their time developing new libraries rather than inventing new programming languages.
I also disagree here. I would, however had, say, that new languages should be well-designed. Many new languages suck. Old languages also suck. Designing a great language is very hard. If it is just a toy or research language then this is fine, but once a language is meant to be "real", it really needs to have compelling use cases and be great in many areas including documentation.
> These features are simply not available in all other languages. Java's meta-programming features, for example, are just not powerful enough to implement a system like ActiveRecords. Rails is only possible because of Ruby.
That's also incorrect. You can create any DSL as you like in Java too. Ruby just makes this a lot easier out of the box. Plus, you can also have great websites without rails.
> Ruby on Rails was designed to make it possible to build websites without understanding type theory, or memory management, or object-oriented design patterns.
Ok so ... why would this not be possible in Java? Why would he have to write Java code for a library to be used in this regard?
> Ruby on Rails provides a concise way for expressing: do this when the button is clicked
But you have the same in many other languages and frameworks too. I mean this is how PHP was started initially.
> The "do this" part is implemented in Ruby as a first-class function. How would it be implemented in languages like Java which don't support them?
Write a solid DSL.
> The programming language directly shapes the design of its libraries.
If this were true, why would GTK have glib+vala? I mean, they could just rely
on C directly, right?
Besides, ruby is just a wrapper over C really.
> The more powerful the language, the easier the libraries are to use.
That part is true. A better designed language makes for better libraries or a chance to have better libraries. I noticed this when I compared my PHP code to my ruby code. I am not a good programmer, but my ruby code is much better on every level than the equivalent PHP code. Fewer lines too. While this also has to do with experience, at the end of the day PHP is simply a much worse language than Ruby is. At some point I decided I don't want to invest into languages that suck when I could be using better languages instead. That is also why I stopped writing shell scripts - it is just a waste of time having them.
Rails is also, by the way, fairly well documented. So I am not saying all in ruby has horrible documentation of course.
> now it is unfortunately also crawling behind perl into extinction. This is very unfortunate - I still use ruby almost daily as the ultimate glue language. But this can not be denied now that ruby is following the extinction path perl already had going some years before.
I'm pretty sure that can be denied.
Rails and Ruby (both separately and as a unit) is still absolutely huge. It's launching massive new releases regularly and still underpins a healthy chunk of the top websites on the planet (Shopify, GitHub, Airbnb, Twitch, Hulu, Kickstarter, Zendesk, Basecamp, Crunchbase, Dribbble etc etc) and is still taught to new developers as well.
I know that HN is famously a discussion forum where users comment based on the titles of submitted articles, rather than their content.
With that said, the divergence in comments on this very insightful and well written article will soon provide an unusually clear means of determining who is commenting on the title and who is commenting on the article.
The omission of quotations in the title triggered my Lisp-damaged brain to man the walls, only to immediately be met with Ruby and Scheme examples. False alarm.
That's fair. It's also the case that to some extent HN's article titles serve the same purpose as that one line description in a speed dating event. They're ice breakers, everybody has the same prompt and then writes about that, and even if they did read the article which I agree often they don't, they come at it from a different angle.
I feel similarly to the article author, it is trivially true that we could express anything in all the general purpose languages, that's what general purpose even means, but I find for Computer Languages the Weak Sapir-Whorf Hypothesis checks out pretty well. The language changes how you think about the problem.
As a long-time HN contributor, I believe in visualizing myself like water flowing downhill. As such, I certainly would never try to overturn the prevailing culture of commenting on article titles and in fact engaging in it myself from time to time.
Yes! This is also why I think it's stupid that languages are now trying to kill their most popular libraries as a matter of principle.
E.g. node says "oh no, you need a library to write tests!" and now that means that you have to have a testing framework built into your runtime. And of course it's just another library, really, that competes with the original one, but this one is blessed with standards so it has a monopolistic advantage that will deter further innovation.
> And of course it's just another library, really, that competes with the original one, but this one is blessed with standards so it has a monopolistic advantage that will deter further innovation.
It's called convenience. You're free to create a testing library so good that it'll knock socks off the stdlib one.
My question is so simple: why is a level playing field seen as bad now?
Have we given up on having a market economy? You can't have a fair game when one team playing is also the referee. Yet everywhere I look that's the way of it. Apple runs the app store so that they can also ensures that every successful app is theirs. The supermarket stocks the shelves, but also uses their position of power to kill successful independent brands. Node takes libraries which have taken years of work and shits out builtins with at most a week invested.
I think it's a national embarrassment: anticompetition to the point of communism held up as if it were the genuine spirit of the American Dream.
All programming languages are equivalent meaning their level of expressiveness is the same, it's not an opinion it's a fact. Each language comes with its runtime and its peculiarities but potentially you can always make any feature that another language runtime has with any language, even though probably not with the same performance and efficiency has been that feature native to the runtime itself.
So there are no "more powerful languages" just runtimes that allow you to hide away some stuff considered stable enough that they become some kind of primitive for the programmer, now we may have different opinions on what elegant code is, but personally I'd like to avoid code that directly (i.e. no kind of abstraction) relies on runtime features and instead express clearly my intention in code, but I recognize the productivity gains.
Furthermore, turing completeness says nothing about expressiveness or capability. Imagine a language that has no IO. Such a language would be able to compute any function any other language can but not do anything viewable by the rest of the world. So obviously not equivalent.
I understand and agree, what I was trying to say is that one should not confine ones thinking by the constraints of a tool, would it be a programming language or whole framework, but to express everything as freely as possible without details of implementation only then one can go deeper and add concreteness that brings its set of constraints and all of this should be possible in any programming languages.
No I wasn't, it was a really interesting read thank you, but that blog post seem to me like an argument for me not the OP point of view, because if you refuse to understand how things work by blindly delegating to libraries and frameworks (like RoR) you become a "Blub" programmer that thinks in the way of constructs and decisions that the library/framework authors made.
Yeah I can see that, but that lisp feature is not exclusive to lisp, if you know what you want and what you are doing you can implement the very same thing in any other language, you may say it is convenient that lisp already has it, but it does not make it more powerful. I don't know list, but there will surely be something that is missing from it that another language has it, now I ask you which is more powerful? See? Everything is relative to what you want to do. The very author of the blog you shared is falling in the same set of programmers he wants to criticize because now he thinks in lisp macro and the very moment he cannot use lisp, he will feel lost but has he stopped and thought that what he needed was something to manipulate code at compile time he could have used any language
I just came across a situation where I had a DSL but it was clear that a language would have been better. What I don't like about this is the dogmatic tone which is pretty common in IT. Don't to it that way, do it my way! Sometimes a DSL is a solid choice, sometimes a language is a better one, sometimes you might want to support both but I guess "Choose the right abstraction for your domain" doesn't make for a clickbait title.
All programming languages are domain specific, so presumably he is referring to English (or another natural language of the same nature). Meaning that he must be saying that sometimes letting the vibes flow is best.
No, I meant a General Purpose Language (GPL) or actually this was an application specific language. You don't need to be so pedantic. Yes, the L is for language but the idea of a DSL is not well defined but these remarks reinforce my argument that people are too dogmatic.
I wasn't trying to be dogmatic, I was genuinely trying to understand what you were trying to say, because it didn't seem to relate to languages vs libraries, and I found it confusing.
Languages are "Easy" to design. There is nothing wrong designing a new language and it can be fun.
There is however something wrong with releasing your new language! In most cases you should show it off to close friends, or your professor, and then burn it and all the source. Sure you might be better than the current language, but you won't be enough better as to be worth it. (even if the language is notoriously bad C++ where it is easy to be better - you won't be enough better as to be worth it).
If you want a better language there are two good options: switch to a different one that already exists; or make your language better. There are lots of great choices for languages out there if you want to switch. If the language you are thinking of doesn't have an active community of people working on making it better, it probably isn't a good choice.
Whichever language you choose though, libraries are the hard part. There are a lot of bad libraries, we need someone to write a better one - but only if one doesn't exist! For the great libraries out there, most need someone to contribute.
A large part of libraries is the consistent interface. Often there is a great libFoo and libBar, but their APIs are not consistent and so we need a libBarWithFooStyleInterface, and/or libFooWithBarStyleInterface. Better yet, we need everyone to come together and agree on how the interface should be and then make both use that new standard - cleaning Augean stables with a toothbrush seems like an easier task. Of course in the real world there a hundreds of libraries each with a great interface that is not consistent with the others.
The best example of all is Prolog. It is always held up as the paradigmatic representative of logic programming, a rare language paradigm. But it doesn't need to be a language. It is really a collection of algorithms which should be a library in every language, together with a nice convention for expressing Prolog things in that language's syntax.
(My comment is slightly off-topic to the article but on-topic to the title.)
The main thing about prolog isn't the algorithms. In fact, the actual depth-first search isn't even part of the standard.
The nice thing about prolog is that you write logical rules, and they can get used in whatever order and direction that is needed. By direction, I mean that if you define "a grandparent is the parent of a parent", you can now use that rule not just to evaluate whether one person is a parent (or to find all grandparents) but also to conclude that if you know someone is a grandparent, and they are the parent of some one, then that person is someone's parent. Ok, it can also do recursion, so if you define an ancestor as a parent or the parent of an ancestor it will recurse all the way up the family tree. Neat.
You could write some kind of runtime that takes c code and brute-forces its way from outputs to inputs, except that regular imperative code allows for all kinds of things that make this impossible (e.g. side-effects). So then, you'd be limited to some subset, essentially ending up with a domain specific language again, albeit with the same syntax as your regular code, rather than those silly :- symbols (although LISP looks much sillier than prolog IMHO).
What the article is getting at is that if you use some features specific to a language, it's hard to embed your code as a library in another language. But is it? I mean, DLLs don't need to be written in the same language, there's stuff like JNI, and famously there's stuff like pytorch and tensorflow that runs CUDA code from python.
> By direction, I mean that if you define "a grandparent is the parent of a parent", you can now use that rule not just to evaluate whether one person is a parent (or to find all grandparents) but also to conclude that if you know someone is a grandparent, and they are the parent of some one, then that person is someone's parent.
Not necessarily.
Could you please expand? Because I have the same state of knowledge of the previous poster. I would like to learn if I'm wrong.
Someone who is a grandparent may also have other children who do not have children.
Debugging rarely works correctly between languages, and features like "find all references" usually break too. Maybe that's not an issue with Prolog because a C logic solver would also be hard to debug, but it's a problem with many template languages.
>The nice thing about prolog is that you write logical rules, and they can get used in whatever order and direction that is needed.
This generalizes!
Prolog: declare relations. Engine figures out how to satisfy them. Bidirectional -- same rules answer "is X a grandparent?" and "find all grandparents."
LLMs do something similar but fuzzier. Declare intent. Model figures out how to satisfy it. No parse -> AST -> evaluate. Just: understand, act.
@tannhaeuser is right that Prolog's power comes from what the engine does -- variables that "range over potential values," WAM optimization, automatic pruning. You can't get that from a library bolted onto an imperative language. The execution model is different.
Same argument applies to LLMs. You can't library your way into semantic understanding. The model IS the execution model. Skills aren't code the LLM runs -- they're context that shapes how it thinks.
Prolog showed that declarative beats imperative for problems where you can formalize the rules. LLMs extend that to problems where you can't.
I've been playing with and testing this: Directories of YAML files as a world model -- The Sims meets TinyMUD -- with the LLM as the inference engine. Seven architectural extensions to Anthropic Skills. 50+ skills. 33 turns of a card game, 10 characters, one LLM call. No round trips. It just works.
https://github.com/SimHacker/moollm/blob/main/designs/stanza...
https://github.com/SimHacker/moollm/tree/main/skills
The syntax of Prolog is basically a subset of the language of First Order Logic (sans quantifiers and function symbols), it doesn't get any more minimal than that. What's special in Prolog compared to imperative languages including functional languages is that variables aren't "assigned" but implicitly range over potential values until satisfying the context, like in math formulas for sets. Yes you can express that awkwardly with tons of type annotations and DSL conventions so that you never have to leave your favourite programming language. But then there's the problem of a Prolog "engine" doing quite a bit more than what could be reasonably assumed behind a synchronous library call, such as working with a compact solution space representation and/or value factoring, parallel execution environment, automatic value pruning and propagation, etc.
The integration of a Prolog backend into a mainstream stack is typically achieved via Prolog code generation (and also code generation via LLMs) or as a "service" on the Prolog side, considering Prolog also has excellent support for parsing DSLs or request/responses of any type; as in, you can implement a JSON parser in a single line of code actually.
As they say, if Prolog fits your application, it fits really well, like with planning, constraint solving, theorem proving, verification/combinatoric test case enumeration, pricing models, legal/strategic case differentiation, complex configuration and the like, the latter merely leveraging the modularity of logic clauses in composing complex programs using independent units.
So I don't know how much you've worked hands on with Prolog, but I think you actually managed to pick about one of the worst rather than best examples ;)
You can implement a JSON parser in a single line of code in C, but why?
To win an entry at IOCCC.
> So I don't know how much you've worked hands on with Prolog, but I think you actually managed to pick about one of the worst rather than best examples ;)
Seems more like an interesting research project than something I'd ever deploy in an application serving millions of users
I can't speak to any sort of scalability but I can definitely say that not everything needs to be built for millions of users. There's plenty of utility in tools you use to help even a single person (even yourself!)
> Seems more like an interesting research project
You mean like the kinds of problems digital computing was originally invented to solve?
You know that still exists, right? There are many people using computers to advance the state of Mathematics & related subjects.
By that same logic, we don't need object oriented features in a language, because we have closures and can get the same functionality with a library.
Sometimes, having a language with a distinct syntax is nicer.
Typically, what's nicer is the absence of other features that interfere with the important ones.
For example, Prolog isn't a general purpose functional or imperative language: you can assert, retract and query facts in the automatically managed database, risking only incorrect formulas, inefficiencies and non-monotonicity accidents, but not express functions, types, loops, etc. which could have far more general bugs.
I like how classes escape closures but then dependency injection frameworks have to work around that because now it is hard to think of construction as passing arguments to functions in the correct order.
I am so glad LLMs eliminate all of that and just call functions in the right order.
> I am so glad LLMs eliminate all of that
When LLMs do something, it's always because everybody was already doing it.
The noise you see online about it exists exactly because most people don't understand and can't use DI.
No, LLMs like NextJS style injection as much as anyone.
There is nothing magical about topological sort and calling constructors in the right order, which is all DI is.
I dislike it a lot, it is exactly like any other construct that allows you to throw code at anything in a way that sucks (Haskell lens, optics, monad transformers).
It allows people to granularize the whole codebase to the point where you can’t do much about it. For most, they should just stick with functions, no one can build 100 levels deep function callstacks without it being cumbersome, but DI makes it a breeze.
I fell out of love with Java not because of the language, but because it got tied up with DI. Don't get me wrong, the allure of DI is really neat. Make all sort of interfaces and just call the function and it can be implemented by dozens of things. Perfect for a lot of use-cases. But then reality hits, and you eventually realize how complex the entire codebase is because it's pattern 1, pattern 2, p3, p4, etc... People are so obsessed with GoF patterns that they're not getting anything done other than spending the first month on a beautiful API.
Then I got into Python and people were building useful server APIs in a day.
Both have their place, but I think the problem with the first route is that EVERYTHING ends up with Spring or CDI and complexity overload even if only 1 thing will ever be "implemented".
> There is nothing magical about topological sort and calling constructors in the right order, which is all DI is.
Lol... That's exactly the kind of thing we call "magic" in software development.
Anyway, if your framework is entirely based on DI, everybody that uses the framework will use DI, and the LLMs will generate code for it that uses DI. That does not contest my point in any way.
Absolutely. In the same direction as some people I've heard along the lines of "Anything you can do with language X, can be done with assembler, just have some routines for that in your stash"
The only languages I know that can do prolog-like-constructs as-a-library are lisps, or at least langs that have reasonable symbol constructs. Usability is way way worse if you can’t talk about variables as first class objects.
I was talking to Bob Harper about this specific issue (context was why macro systems are important to me) and his answer was “you can just write a separate programming language”. Which I get.
But all of this is just to say that doing relational-programming-as-a-library has a ton of issues unless your language supports certain things.
I believe Rust uses datafrog, Datalog as a library to implement some of its next gen solvers for traits and lifetimes. Not a lisp and maybe this still isn’t as elegant as you had in mind? Curious how this library compares for you.
https://github.com/rust-lang/datafrog
If you want to see what it looks like when you actually embed Datalog in your language, have a look at Flix: https://flix.dev/
(Select the "Usinag Datalog..." example in the code sample dropdown)
The Rust code looks completely "procedural"... it's like building a DOM document using `node.addElement(...)` instead of, say, writing HTML. People universally prefer the declarative alternative given the choice.
The experimental "Polonius" borrow checker was first implemented with datafrog, but I believe it's been abandoned in favour of a revised (also "Polonius") datalog-less algorithm.
Haskell can do the same, and does with a lot of little embedded DSLs.
Yea I’ve wanted to try using logict to do some larger logic programming stuff. I’ve done it with list monad but found a lot of speed issues, never quite figured out why it was so slow.
Speaking of prolog, any recommendations for resources learning it at a stage somewhere between "draw three circles" and "draw the rest of the owl"
I don't have real work I need prolog for, but I find it an interesting subject, My personal learning goal, the point where I can say I know prolog reasonably well is when I can get it to solve this mit puzzle I found, a sort of variant of soduku. I found a clever prolog solver for soduku that I thought could teach me more in this domain, but it was almost to clever, super optimized for soduku(it exploited geometric features to build it's relationships) and I was still left with no idea on how to build the more generic relationships I need for my puzzle(specific example if soduku cells were not in a grid how could they be specified?), in fact I can find very little information on how to specify moderately complex, ad hoc relationships. One that particularly flummoxed me was that some rules(but you don't know which) are wrong.
https://www.swi-prolog.org/pldoc/man?section=clpfd-sudoku
I got recommended and have in my bookshelf "The art of prolog" waiting for the year when I have time (or need) for it.
Prolog Programming for Artificial Intelligence" by Ivan Bratko, is a reasonable text book on Prolog.
The only decent Prolog book out there, IMNSHO, is "Clause and Effect" by Clocksin. Maybe some of the later chapters might help?
All the other books that I looked at were pretty awful, including the usual recommendations.
I would go with the reference, "The Art of Prolog".
If you want to learn LP concepts in general, Tarski's World is a great resource as well.
Prolog is great because when it works it feels like magic. You give it some pragmas and it tells you the answer. The downside is when it doesn't work it also feels like magic. It's not easy to reason about the amount of work it needs to do. If your Prolog program is taking a long time to run it is hard to figure out if it is going to take 2 hours or 4,000 millennia.
Disclaimer: I've no idea what I'm talking about. :)
But I have heard repeatedly that the good thing of prolog is the compiler, that takes information and queries that would be awful inefficient, and convert them in something that actually works. So I'm not sure... of course, you can convert virtually any language in a kind of library with some API that basically accepts source code... but I'm pretty sure is not what you meant.
I think the examples others have highlighted show the problem with just making it a library. They’re all lacking a lot of features from Prolog, particularly in terms of optimization. Just use Prolog if you need its features and invoke SWI-Prolog like you’d call any other language’s interpreter.
Agree. The optimization caveat also applies to OOP, another example someone threw in above.
Sure you can implement OOP as a library in pretty much any language, but you’ll probably sacrifice ergonomics, performance and/or safety I guess.
Are there any particularly excellent examples of prolog implemented as a library you could point us to?
As an example of a use case, "Gerrit Code Review"[1] is written in Java and uses prolog for the submit rules.[2]
I haven't looked into the implementation. But taking a brief glance now, it looks interesting. They appear to be translating Prolog to Java via a WAM representation[3]. The compiler (prolog-cafe) is written in prolog and bootstrapped into Java via swi-prolog.
I don't know why compilation is necessary, it seems like an interpreter would be fast enough for that use case, but I'd love to take it apart and see how it works.
[1]: https://www.gerritcodereview.com/ [2]: https://gerrit-documentation.storage.googleapis.com/Document... [3]: https://gerrit.googlesource.com/prolog-cafe/+/refs/heads/mas...
Not exactly prolog, but logic programming implemented as a library/DSL: https://minikanren.org/
If it's a DSL then it's "writing a new language" and you're just calling from a native API, no?
Embedded DSLs are libraries. They are the epitome of the advice to write a library. It just so happens that the library abstractions could map to a language if you wanted to add parsing and all of the other machinery.
Clojure's core.logic is based on minikanren, so that fits the bill.
My time to shine! https://news.ycombinator.com/item?id=45902088
References were Racket with the Racklog library¹. There's also Datalog² and MiniKanren, picat, flix. There were tons of good comments there which you should check out, but PySwip seemed like "the right thing" when I was looking at it: https://github.com/yuce/pyswip/
...documentation is extremely sparse, and assumes you already know prolog, but here's a slightly better example of kindof the utility of it:
https://eugeneasahara.com/2024/08/12/playing-with-prolog-pro...
...ie:
...the point being there's sometimes some sort of "logic calculation that you wish could be some sort of regex", and I always think of prolog as "regexes for logic".One time I wished I could use prolog was trying to figure the best match between video file, format, bitrate, browser, playback plugin... or if you've seen https://pcpartpicker.com/list/ ...being able to "just" encode all the constraints, and say something like:
...this is a terribly syntactically incorrect example, but you could imagine that this would be horrific code to maintain in python (and sqrt(horrific) to maintain in prolog), but _that's_ the benefit! You can take a well-defined portion and kindof sqrt(...) the maintenance cost, at the expense of 1.5x'ing the number of programming languages you need to expect people to know.not OP, but for clojure : https://github.com/bobschrag/clolog
not prolog but logical programming in python: https://sites.google.com/site/pydatalog/
Think of Prolog the language as just a serialization of a Prolog AST. The AST could be constructed in any programming language as a library. But what if we want to share and store these ASTs? We can serialize them to Prolog the language! The language has value even if it’s a library.
Prolog admittedly mystifies me even more than the Haskell family. How do you do anything effectful, like read from a file, or output arbitrary data to standard out, or set up a loop to process keyboard events every 1/n seconds? How do you make system calls?
By thinking in LP terms, like FP, LP requires rewiring the brain to think differently how to approach algorithms.
Here is a sample on how to read a file.
https://lpn.swi-prolog.org/lpnpage.php?pagetype=html&pageid=...
How to make syscalls,
https://www.swi-prolog.org/pldoc/man?section=foreign
Prolog is a contrived example. It's small and simple enough to be implemented as a DSL embedded in another language, reusing most of the parser and leaningn its execution logic.
Now try to produce a library that adds compile-time features: static types, lifetimes, the notion of const and constexpr, etc. You can, of course, write external tools like mypy, or use some limited mechanism like Java annotations. But you have a really hard time implementing that in an ergonomic way (unless your language is its own metalanguage, like Lisp or Forth, and even then).
Creating a library that alters the way the runtime works, e.g. adding async, is not entirely impossible, but usually involves some surgery (see Python Twisted, or various C async libs) that results in a number of surprising footguns to avoid.
Frankly, even adding something by altering a language, but not reworking it enough to make the new feature cohesive, results in footguns that the source language did not have. See C#'s LINQ and exceptions.
But why should it be though? You haven’t really addressed that. It’s like saying “Haskell shouldn’t be its own language, it should just be a couple of features like lambdas integrated into a JavaScript library”. Well if you do that you get some nice features in JavaScript but you’ve done away with the whole value proposition of pure functional programming. That’s an actual loss, there’s something to be said for maintaining a pure set of features that gives languages different properties and guarantees you can’t get with “everything is just a lib to an imperative language”
Pure functional programming and lazy evaluation.. sure, you could create classes and a meta-function that selectively eval's thunks at a time, but the call site of that kind of library would look atrocious..
You might be able to hack on some of the datatype semantics into JS prototype-based inheritance (I'd rather start with TypeScript at that point, but then we're back at the "why isn't it a library" debate) to keep those ontologies from being semantically separate, but that's an uphill battle with some of JS's implicit value conversions.
I consider Logic Programming languages to be the go-to counterargument to TFA but yeah, anything with lazy eval and a mature type system are strong counterexamples too.
How many Prolog programmers does it take to change a lightbulb?
false.
https://www.j-paine.org/dobbs/prolog_lightbulb.html
I always wanted to write a compiler whose front-end consumes Prolog and back-end emits PostScript, and call it "PrologueToPostscript".
prologue: a separate introductory section of a literary, dramatic, or musical work.
postscript: an additional remark at the end of a letter, after the signature and introduced by ‘PS’.
Except when implemented as library it doesn't take advantage of WAM and related JIT.
i treat it like i treat SQL.
I was big fan of Scala a decade ago. The idea of a “scalable language” where DSLs could be built within the type system seemed super powerful. I lost my enthusiasm when the community decided they wanted to use it as Haskell on the JVM.
I’m hoping more recent developments, like WASM or Graal, provide a route for more flexibility when selecting languages. It’s nice to see Rust slowly become a serious choice for web development. Most of the time JS is fine, but it’s good to have the option to pull out a stricter low-level language when needed.
That's the main issue I found with Scala, and as I grow older also with certain libraries (especially in unit testing land) that try to add a language / DSL on top. Not only do you need to learn Scala, you need to learn various DSLs on top of that depending on what you use or want to achieve. Some egregious examples here and there.
I'm sure there's good use cases for it - one impressive example at the time was using functional programming to create Hadoop map / reduce jobs, a oneliner in Scala was five different files / classes in Java. But for most programming tasks it's overkill.
You can write boring code in Scala, but in my (limited) experience, Scala developers don't want to write boring code. They picked Scala not because it was the best tool for the job, but because they were bored and wanted to flex their skills. Disregarding the other 95% of programmers that would have to work with it.
(And since these were consultants, they left within a year to become CTOs and the like and ten years on the companies they sold Scala to are still dealing with the fallout)
> Not only do you need to learn Scala, you need to learn various DSLs on top of that depending on what you use or want to achieve
That is AFAIK the "curse of lisp" because is so easy (and needed and encouraged) to write SDLs, any ecosystem grows many languages in a hurry, so suddenly that elegant minimalistic beautiful pure language, becomes 1000 beautiful clean languages. Now you have to learn them all...
> You can write boring code in Scala, but in my (limited) experience, Scala developers don't want to write boring code. They picked Scala not because it was the best tool for the job, but because they were bored and wanted to flex their skills. Disregarding the other 95% of programmers that would have to work with it.
Intersting observation.
So basically Scala is to the JVM what Perl is to scripting?
You can write readable Scala code, just like you can write readable Perl code. But both languages allow you to to write very concise and cryptic code as well. Scala doesn't seem to optimize for the "one obvious solution" approach like Python does. Scala seems to be more TIMTOWDY like Perl.
Scala was designed from the beginning to support classical Java-style OOP code and also Haskell-like functional code. These are 2 very different styles in one language. And then Scala supports defining DSLs which give you even more flexibility.
You can write boring code in Scala, but in my (limited) experience, Scala developers don't want to write boring code. Guilty as charged!
> They picked Scala not because it was the best tool for the job, but because they were bored and wanted to flex their skills.
Guilty as charged!
> Disregarding the other 95% of programmers that would have to work with it.
No. Your coworkers end up being the other 5% of programmers that have the same taste as you. Interviewers ask about monads and lenses. It's fine, as long as everyone is on the same page. Which... they kind of have to be.
i use scala because i can write more expressive and simpler/safer code than java language.
> I lost my enthusiasm when the community decided they wanted to use it as Haskell on the JVM
It's not the whole community, not by a long shot. Don't judge Scala by the Scala subreddit.
Most new things you'll see written about Scala are about solving difficult problems with types, because those problems are inexhaustible and some people enjoy them, for one reason or another. Honestly I think this shows how easy and ergonomic everything else is with Scala, that the difficulties people write about are all about deep type magic and how to handle errors in monadic code. You can always avoid that stuff when it isn't worth it to you.
The type poindexters will tell you that you're giving up all the benefit of Scala the moment you accept any impurity or step back from the challenge of solving everything with types, and you might as well write Java instead, but they're just being jerks and gatekeepers. Scala is a wonderful language, and Scala-as-a-better-Java is a huge step up from Java for writing simple and readable code. It lets you enjoy the lowest hanging fruit of functional programming, the cases where simple functional code outshines OO-heavy imperative code, in a way that Java doesn't and probably never will.
Haskell is usually used as a DSL. I believe Haxl is used at Meta and TidalCycles is a good example of another DSL built in Haskell.
Although I agree the usual lens, optics, machines, pipes or other higher kinded libs are completely unnecessary, solving problems you do not want to have and have dire performance implications, but are at least correct and allow you to throw code at problems quickly, even though that code sucks in all ways except correctness.
I don’t agree that pipes should be in your list, at least for some use cases. Streaming data through pipes gives capabilities that systems written in more traditional ways often simply don’t match. Look at the use of the Stream API in Java for an example of the utility of this outside of the Haskell context.
Pipes also don’t necessarily have “dire performance implications”, but it depends a lot on the implementation. Haskell libraries don’t always emphasize real world performance as a top criterion. E.g. see https://github.com/composewell/streaming-benchmarks for some truly wild variations in performance across libraries (disclaimer: I haven’t investigated or verified those numbers.)
Have you tried Clojure(Script)? It could be just what you need, bottom-up programming in a Lisp-like language essentally means extending the langauge in order to solve the problem at hand.
Or, as Paul Grahmam put it in his 1993 book On Lisp: "a bottom-up style in which a program is written as a series of layers, each one acting as a sort of programming language for the one above"
https://paulgraham.com/progbot.html
https://www.paulgraham.com/onlisptext.html
Here is a talk that explains the concept in Clojure, titled Bottom Up vs Top Down Design in Clojure:
https://www.contalks.com/talks/1692/bottom-up-vs-top-down-de...
I recently started to learn Scala and I love it, also for it's functional aspect. Regarding your comment, it feels like scala is generic enough to be used also in other ways, and definitively for DSLs. What do you think it's missing?
I think the GP is thinking about how libraries and ecosystems are often more important than the language. Most emphasis in scales is in a collection of competing frameworks that, today, are very FP oriented. Some hide the category theory while others put it up front, but it's ultimately what you do. The libraries that wanted to do imperative OO lost most support.
Also see, for instance, Java. There's Java, the language that keeps improving, and then the Spring ecosystem, which is what 95% of programmers end up having to use professionally, with its heavy "magic" component. Writing services avoiding Spring is going against the grain. It might as well be part of the language as far professional Java use is concerned.
Communities matter more than the language features, and Java is all Spring, and now Scala is really a choice of Zio and Cats
Hopefully project Panama will see better interoperability with libraries using the C memory model however migration does not appear to be easy. Arrow Java still uses sun.misc.Unsafe for native memory access.
Reminds me of a joke.
I have a problem.
Right, I'll design a DSL.
Hmm. Now I have two problems.
Doing fancy things with types used to interest me, now it's the last thing I want to touch, after being burned too many times by libs trying to be clever.
I used Scala a few times when it was semi popular, just seemed like Java but with lots of redundant features added. Not sure what the aim was.
Certainly one can get too clever/fancy, but I appreciated that Scala let me express things in the type system that made more of my program confidently correct at compile time than I could do in Java. I hate writing tests, and with Scala, I could write fewer of them, but still be confident that things were working as intended.
But ultimately using Scala at the place I worked at the time was a failure. A couple of my co-workers had introduced it, and I joined the bandwagon at some point, but it just didn't work out.
Many Java developers inside the company didn't want to learn, and it was really hard to hire good Scala developers. The ones who did learn (myself included) wrote terrible Scala for a least the first 6 months, and that technical debt lingered for a long time. When other people outside the team (who didn't know Scala) needed to make changes to our code, they had a lot of trouble figuring things out, and even when they could, the code they wrote was -- quite understandably -- bad, creating extra work for us to review it and get it into shape.
I also feel like Scala suffers from similar complexity/ways-to-do-things problems as C++. I often hear people say things like "C++ can be a safe, consistent language if you just use a subset of it!", and then of course everyone has a subtly (or not-so-subtly) different subset that they consider as The One True Subset. With Scala, you can write some very complex, type-heavy code that's incredibly hard to read if you are not well-versed in type/category/etc. theory (especially if you are using a library like cats or scalaz). Sure, you could perhaps try to come up with some rules around what things are acceptable and what aren't, but I think in this case it's a hard thing to specify, and different people will naturally disagree on what should be allowed.
I really wanted Scala to succeed at our company, but I think that's hard to do. I feel like the ideal case is a small company with just a few tens of developers, all whom were hired specifically for their Scala expertise, with a product/business that is going to keep the number-of-developers requirement roughly static. But that's probably very rare.
C++ was how I'd describe it, too many different ways to do simple things. I guess Java++
> I used Scala a few times when it was semi popular, just seemed like Java but with lots of redundant features added. Not sure what the aim was.
Blub is a great language!
then why is java adding back half baked versions of scala features every major release
Saying that the new Java features are half baked, to me, shows you're just feeling hurt because people prefer Java over your favourite language.
Java may not be the pinnacle of programming languages, but since Java 8, pretty much every feature it's added has been absolutely excellently done.
i mean, it follows the java philosophy (preseving backward compat). theyve done great work improving java. but i see no reason to use it over scala where i get better features, its more like a java 2.0
Then don't. You can use Scala to your heart's content. No one is stopping you.
I had to work on a Scala codebase at some point, and I thought it horrible. I judge a language on how easy it allows you to create an unreadable mess. Scala makes it incredibly easy. And the people that enjoy Scala seem to like "unreadable messiness" as a feature.
I found it fun to learn the basics, and it was interesting to think of problems from a FP approach, but it is never something I would use in the real world.
I vastly prefer Java. The features it imported from Scala were fine, made the language better. It doesn't need to import everything.
Cause it actually needed lambdas and things that go with it. Didn't need all the Scala-specific data structs like Array.
And the most important thing Java was always missing until recently, virtual threads, were lacking in Scala too.
Virtual threads is a JVM & stdlib feature, not a language feature.
(And I'd disagree that virtual threads were all that important compared to language features.)
In pretty common applications, virtual threads will make the difference between chaining futures (this.then(that).then(...)) vs not, all throughout your code. Or some frameworks had far uglier ways to deal with cooperative multitasking.
Lambdas weren't simple to shoehorn into Java. But most of the recent changes have been implemented as well or better, or as well as you could imagine while maintaining backwards compatibility and Java-ness.
Records/sealed interfaces (ADTs) are quite clean.
Text Blocks are better in Java IMO. The margin junk in Scala is silly.
Scala is a fantastic language and in fact I'd say it's the language that proves the article wrong.
Java was the language where "write libraries instead" happened, and it became an absolute burden. So many ugly libraries, frameworks and patterns built to overcome the limitations of a simple language.
Scala unified the tried-and-tested design patterns and library features used in the Java ecosystem into the core of its language, and we're better off for it.
In Java we needed Spring (urghh) for dependency injection. In Scala we have the "given" keyword.
In Java we needed Guava to do anything interesting with functional programming. FP features were slowly added to the Java core, but the power and expressivity of Java FP is woeful compared what's available at the core of Scala and its collections libraries.
In Java we needed Lombok and builder patterns. In Scala we have case classes, named and default parameters and immutability by default.
In the Java ecosystem, optionality comes through a mixture of nulls (yuck) and the crude and inconsistently-used "Optional". In Scala, Option is in the core, and composes naturally.
In Java, checked exceptions infect method signatures. In Scala we have Try, Either and Validated. Errors are values. It's so much more composable.
There's so much more - but hopefully I've made the point that there's a legitimate benefit in taking the best from a mature ecosystem and simple language like Java and creating a new, more elegant and complete language like Scala.
I think you misunderstood the article (or only read the first couple paragraphs). The author sets the stage with the statement in the article title (a quote heard from other people), but shows that those fancy language features in some languages are exactly why rich, easy-to-use libraries can be built. And that some of these rich, easy-to-use libraries simply cannot be built in some languages that lack those features.
So you don't actually disagree with the article.
> the language that proves the article wrong
It helps to actually read it. The title is in quotes because the point of the article is to refute it.
I would love to have a scripting language has typed features and you can replace bash with.
What comes close is:
Have you seen nushell? It lets me one-liner so many things that would have previously taken breaking out a "real" language to do
Contrived example:
outputsWith this:
This becomes valid Ruby: (drops your size formatting, so not strictly equivalent)Which isn't meant to "compete" - nushell looks nice -, but to show that the lower-threshold option for those of us who don't want to switch shells is to throw together a few helpers in a language... (you can get much closer to your example with another helper or two and a few more "evil" abuses of Ruby's darker corners, but I'm not sure it'd be worth it; I might a wrapper for the above in my bin/ though)
I've tried nushell and other shell replacements and it just feels like I'm learning a new programming language for no good reason
To be fair the example above is easier to remember than:
This example shows nicely how ugly text processing is: you have to use head and tail simply to trim out the first line of ls (the total).
I think it doesn't even work correctly. ls lists files and directories and then picks the first 4 (it should only select files).
And this also uses awk and jq, which are not just simple "one purpose" tools, but pretty much complete programming languages. jq is not even part of most standard installations, it has to be installed first.
> And this also uses awk and jq, which are not just simple "one purpose" tools, but pretty much complete programming languages
In a way that exactly illustrates the GGP's point: why learn a new language (nushell's) when you can learn awk or jq, which are arguably more generally- and widely-applicable than nushell. Or if awk and jq are too esoteric, you could even pipe the output of `find` into the python or ruby interpreters (one of which you may already know, and are much more generally applicable than nushell, awk, or jq), with a short in-line script on the command line.
> awk or jq, which are arguably more generally- and widely-applicable than nushell
That is backwards. I know I said "complete programming languages", but to be fair, awk only shines when it comes to "records processing", jq only shines for JSON processing. nushell is more like a general scripting language — much more flexible.
I'd replace the first part with (which isn't any shorter, but in general if I want a list of files for a pipeline, find is usually more flexible than ls for anything but the most trivial):
For the latter part, I'd tend to think that if you're going to use awk and jq, you might as well use Ruby. ("-nae" effectively takes an expression on the command line (-e), wraps it in "while gets; ... end" (-a), and adds the equivalent to "$F = $_.split" before the first line of your expression (-n))It's still ugly, so no competition for nushell still.
I'd be inclined to drop a little wrapper in my bin with a few lines of helpers (see my other comment) and do all Ruy if I wanted to get closer without having to change shells...
Ruby is a pretty natural fit for shell scripting.
https://lucasoshiro.github.io/posts-en/2024-06-17-ruby-shell...
It's close, but there are some things that could be better to make it easier to access e.g. file size and type. I think maybe a 50-100 line set of helpers and a one line wrapper (to spawn Ruby with -r<helper> -e <command line>) would get you mostly to where nushell is.
Yes, the point was to show that nushell is pretty awesome. I totally punted on the file only part.
I'm aware ;)
Yeah... https://www.sophiajt.com/case-for-nushell/ makes a really good case for Nushell as an alternative to Bash.
Unfortunately, I don't think Nushell brings much benefit for folks who already know Bash enough to change directories and launch executables and who already know Python enough to use more complicated data structures/control flow/IDE features
I'm still rooting for Nushell as I think its a really cool idea.
For me the blocker was having to switch to bash/powershell when moving to a different machine (ie: servers, work machine, etc..). I would end up needing to redo same things to be compatible with the existing tools; eventually I just gave up and got used to readily available shells instead.
Ok if it's not for you. But there is of course a very good reason — work with objects in the pipeline instead of "dumb text". Also PowerShell and nushell are quite nice to learn, whereas Bash is absolutely horrible.
I wonder if this is a case of "worse is better", or just the long-term entrenchment of text. Because nushell hasn't been adopted all that much compared to bash or even zsh (or a "real" scripting language like python or ruby). I don't know much about PowerShell adoption (haven't used Windows in over 20 years), but I'd assume since it's a first-party system that's default installed(?), it's done better adoption-wise.
I agree that bash sucks, but I really have no motivation to learn something like nushell. I can get by with bash for simpler things, and when I get frustrated with bash, I switch to python, which is default-available everywhere I personally need it to be.
Back to text, though... I'm honestly not sure objects are strictly better than dumb text. Objects means higher cognitive overhead; text is... well, text. You can see it right there in front of you, count lines and characters, see its delimiters and structure, and come up with code to manipulate it. And, again, if I need objects, I have python.
I get the point of "either Bash or straight to a real programming language". That's what I do too, for automation. I like how PowerShell makes one-off tasks easier which would otherwise be the typical pipe of cat, grep, sed, awk etc.
About objects vs. text: I'm convinced that objects are vastly superior. There was a comment about this here with good arguments: https://news.ycombinator.com/item?id=45907248
Well, the reason is you can stop using Bash. If you never write Bash scripts already then you probably don't need it (and also congratulations on doing things right), but most people at least have lazy colleagues that write shell scripts. One day I'd like them to be not awful.
In PowerShell:
ConvertTo-Json? What kind of naming convention is that, especially with all the other commands being lowercase?
The naming convention is `verb-noun`. It's convenient for discoverability and consistency. The short commands are aliases.
The last command is properly cased, because I pressed tab (it auto-completes and fixes the case). The other commands I typed without tab completion. You can write however you want, PS is not case sensitive.
i dont think you need to select name and size, you can just remove it and use `select -first 4`, but cool, I never knew about `/=` syntax
I was trying to replicate the nushell example, which only has name and size in the output.
For me the best benefit of nushell is not the easier syntax, but the static type checks. It catches most typos before running the script, which is a godsend when the script is slow and/or has destructive operations.
Was just about to suggest nushell. I love programming in nushell, the out of the box features are excellent.
this is pretty cool!
You can use various programming languages with shebangs.
C#: https://devblogs.microsoft.com/dotnet/announcing-dotnet-run-...
Java: https://dev.to/toliyansky/scripting-with-java-3i9k
Go: https://golangcookbook.com/chapters/running/shebang/
https://github.com/igor-petruk/scriptisto will let you generate shebang scripts for pretty much any language
OCaml is a scripting language in this sense. No need to compile an executable ahead of time, just have a `#!/usr/bin/env ocaml` shebang (or more realistically: `#!/usr/bin/env -S ocaml -I +unix unix.cma`) at the top of a source file.
Though, I don't think it has the capability for single-file scripts to declare 3rd-party dependencies to be automatically installed.
It also has poor support for Windows.
The best option I've found for this use case (ad-hoc scripting with third party dependencies) is Deno.
I'm hoping Rust will get there in the end too.
There's a trick shared here days ago to add a kind of shebang to Go that may interest you: https://lorentz.app/blog-item.html?id=go-shebang
Discussion: https://news.ycombinator.com/item?id=46431028
Two interesting options for everyday scripting are Python and Powershell.
A nice part of PowerShell: you can `Add-Type` and embed C#/F# when you want.
I am unhappy with python. It degrades fast. It deprecates libraries every minor release and that tends to break the applications I use. Recent examples are distutils and opsaudio.
For everyday scripting -- the types of things where I'd be writing in bash but get frustrated with it and switch to python -- I nearly always only need what's in the stdlib.
Sure, for "applications", the ecosystem can be frustrating at times, but I don't think that's what we're talking about here.
Thats why venv exists. Much better solution than lock files.
Doesn't help much because even the standard library bitrots after enough Python releases. I have things I write today but can't run on a NAS that has older Python. No issues like that with Powershell for example.
I dunno what issues you are running into, but generally, code from old Python should work fine under new releases if you are developing, you just have to set up your venv right up front and install the specific version of libraries that don't have modern Python code.
I still work on projects that were written under 3.6.
If you care enough, you can also use something like asdf to install an older Python alongside the system one.
Python is actually kind of awkward for this use case since you can't import from other files easily unless you are in a proper Python package, which isn't usually the case for everyday scripting.
Lol what.
Python lets you dynamically import from anywhere. The syntax is a bit funky, but thats what llms are for.
No it doesn't. You can't do something like `import ../../foo/bar`. You can mess around with PYTHONPATH and importlib to work around that but that's a horrible hack that also breaks all tooling. Not a good idea.
With Deno you can just import by relative file path and it just works like you'd expect and the tools support it. I wish more languages worked like that.
>You can mess around with PYTHONPATH and importlib to work around that but that's a horrible hack that also breaks all tooling
....no.
import keyword uses importlib under the hood. It just does a lot of things for you like setting up namespace. But importlib has all the functionality to add the code in any python file cleanly.
My custom agent that I use basically has the functionality to wrap every piece of code it writes as a tool and stores it into python files. During tool calls, it pretty much dynamically imports that code as part of a module within the project. Works perfectly fine.
> You can't do something like `import ../../foo/bar`.
https://docs.python.org/3/reference/import.html#relativeimpo...
You'd use:
Common misconception. That doesn't import by relative file path; it imports by relative package path. It's actually quite different. Scripts you run directly aren't in a package so you can't use it at all. You can go above the package root. Namespace packages mean it can jump to other directories.
Everyone wants that to just mean "import relative to this file" but it doesn't.
you won't believe how powerful Python is with libraries. ChatGPT and Claude made a brand new browser, that isn't based on Chromium or Firefox, and yet still follows many aspects of layout correctly. I read the article we're discussing ("stop designing languages") on this browser and I'm currently using it to post this reply.
Knowing that LLM’s have been extensively trained on public code, I wonder how much of it is based on Chromium or Firefox.
That's a good question! You can read through the entire source code for the latest version:
https://taonexus.com/publicfiles/jan2026/171toy-browser.py.t...
it doesn't look like it would be easily derived from Chromium or Firefox, because this code is Python and those don't use Python this way.
By the way is there any feature you'd like to see added to the toy browser? The goal is that one day it's a replacement for Chrome, Firefox, etc. It's being built by ChatGPT and Claude at the moment. Let me know if there are any feature ideas you have that would be cool to add.
A python-based browser? What are you using for the GUI toolkit?
>A python-based browser? What are you using for the GUI toolkit?
Great questions. 1. Yes, for the moment. Like the title of this article suggests - we're using a library! :)
It's great to iterate in Python, which has a large ecosystem of libraries. Believe it or not, there is a chance that in the future it would be able to translate the language into a different one (for example, C++) while using C++ bindings for the same gui libraries. This would speed up its actions by 40x. However, not all of the libraries used have C++ bindings so it could be harder than it looks.
2. Here's the current version of the source code:
https://taonexus.com/publicfiles/jan2026/171toy-browser.py.t...
you can have a quick read through. Originally it was using tkinter for the GUI toolkit. I believe it is still using tkinter, but the AI might be leaning on some other library. As you read it, is it using anything but tkinter for the GUI toolkit?
These libraries are doing a lot of heavy lifting, but I think it is still ending up drawing in tkinter (not handing off rendering to any other library.)
Have you considered PowerShell? It's open-source, and typed, and definitely usable from the command line with lots of resources for.
https://github.com/PowerShell/PowerShell
And dotnet run can now run single files of C# code, with the ability to import other projects and packages if needed.
https://devblogs.microsoft.com/dotnet/announcing-dotnet-run-...https://andrewlock.net/exploring-dotnet-10-preview-features-...
If you just wait a few months, then that program will be written in a typed language. The type checker for Elixir is coming along nicely and every release brings more checks.
Suggest you take a look at https://raku.org for a strongly (but gradual) typed scripting language.
that's just perl with a new coat of paint
Perl 5 does not have types, as far as I know.
I’m taking the GP seriously instead of dismissing it. Raku looks like more fun than nushell tbh.
Raku types are a bit thicker than paint https://gist.github.com/raiph/849a4a9d8875542fb86df2b2eda892...
It has. They are just poorly supported and disliked.
it is so much slower to start than perl, that you don't want to run it for quick one-off tasks
well waiting for Raku (formerly perl6) to be built was like watching paint dry
They should have named it Godot. ;) But now that name is taken.
Lead paint with asbestos sprinkles and radium racing stripes! ;)
Babashka (https://babashka.org/) is an interesting tool for scripting. It's Clojure, so dynamic typing, but it's data orientation makes it a great fit for something like your example.
I wanted to say Haskell with shh[^1] and stack's or nix's shebangs[^2][^3], but interpreted haskell is not particularly fast.
Also I think a Python script is reasonable if you use a type-checker with full type annotations, although they are not a silver bullet. For most scripts I use fish, which is my preferred interactive shell too.
[1]: https://hackage.haskell.org/package/shh
[2]: https://docs.haskellstack.org/en/v3.9.1/topics/scripts/
[3]: https://wiki.nixos.org/wiki/Nix-shell_shebang. On a side note, if you were to use nix's shebang for haskell scripts with dependencies, you should be using https://github.com/tomberek/- instead of impure inputs, because it allows for cached evaluation. I personally cloned the repo to my personal gitlab account, since it's small and should never change
It probably is perl or Python.
@dev_l1x_be: The answer isn't a new typed scripting language. It's recognizing what the interpreter already is.
LLMs are eval(). Skills are programs. YAML is the motherboard.
@unkulunkulu nails it -- "library as the final language", languages all the way down. Exactly. Skills ARE languages. They teach the interpreter what to understand. When the interpreter understands intent, the distinction dissolves.
@conartist6: "DSL is fuzzy... languages and libraries don't have to be opposing" -- yes. Traditional DSL: parse -> AST -> evaluate. LLM "DSL": read intent -> understand -> act. All one step. You can code-switch mid-sentence and it doesn't care.
The problem with opinionated frameworks like ROR and their BDFLs like DHH is that one opinion is the WRONG number!
The key insight nobody's mentioned: SPEED OF LIGHT vs CARRIER PIGEON.
Carrier pigeon: call LLM, get response, parse it, call LLM again, repeat. Slow. Noisy. Every round-trip destroys precision through tokenization.
Speed of light: ONE call. I ran 33 turns of Stoner Fluxx -- 10 characters, many opinions, game state, hands, rules, dialogue, jokes -- in a single LLM invocation. The LLM simulates internally at the speed of thought. No serialization overhead. No context-destroying round trips.
@jakkos, @PaulHoule: nushell and Python are fine. But you're still writing syntax for a parser. What if you wrote intent for an understander?
Bash is a tragedy -- quoting footguns, jq gymnastics, write-only syntax. Our pattern: write intent in YAML, let the LLM "uplift" to clean Python when you need real code.
Postel's Law as type system: liberal in what you accept. Semantic understanding catches nonsense because it knows what you MEANT, not just what you TYPED.
Proof and philosophy: https://github.com/SimHacker/moollm/blob/main/designs/stanza...
Holy slop!
That's a trite, low effort, worthless, content free comment, which totally misses the point and fails to engage. You haven't made any other comments contributing to this discussion, except that one shallow drive by complaint. If you're going to whine about using llms as a shell, then at least try to do better than an llm or redditor yourself.
So do you disagree with any of my points, or my direct replies to other people's points, or is that all you can think of to say, instead of engaging?
Do you prefer to use bash directly? Why? If not, then what is your alternative?
What do you think of Anthropic Skills? Have you used or made any yourself, or can you suggest any improvements? I've created 50+ skills, and I've suggested, implemented, and tested seven architectural extensions -- do you have any criticism of those?
https://github.com/SimHacker/moollm/tree/main/skills
Obviously you use llms yourself, so you're not a complete luddite, and you must have some deeper more substantial understanding and criticism than those two words from your own experience.
How do your own ideas that you blogged about in "My LLM System Prompt" compare to my ideas and experience, in your own "professional, no bullshit, scientific" opinion?
https://mahesh-hegde.github.io/posts/llm_system_prompt/
Your entire blog post on LLM prompts is "I don't like verbiage" in five sentences. Ironic, then, that your entire contribution here is two empty words. I made specific technical points, replied to real people, linked proof. 'Slop' is the new 'TL;DR' -- a confession of laziness dressed as critique. Calling substance slop while contributing nothing? That's actual slop.
This looks to me like partly a false dichotomy. We can design languages and write libraries. Some would even argue that some kinds of "libraries" could be viewed as languages themselves, as much as some languages might as well have been written as libraries in another language.
Also often, the language doesn't live isolated from its implementation (compiler or interpreter). While theory looks at languages via its semantics, in practice as the OP notes it is about the quality of the implementation and what can be reasonably done with the language.
A recent [1] case is Julia. I think it has hit a kind of sweet spot for language design where new performant code tends to get written in Julia rather than in some other language and bound to it. At its core, it is a simple "call functions, passing data in and getting results out" kind of language, but what the functions ("methods") mean and how the compiler does just-ahead-of-time compilation with deep type specialized code means you can write high level code that optimizes very well. Those mechanics operate under the hood though, which makes for a pleasant programming experience ... and there are loads of cutting edge packages being written in Julia. It is less interesting to look at Julia as "just the language".
[1] recent in programming languages is perhaps anything <= 15 years? .. because it takes time to discover a language's potential.
> This looks to me like partly a false dichotomy
Wasn't that the point of the article? That you need both?
Yes, but most of the commenters didn't read the article.
Yup, articles like this where the title is the opposite of the article's message is a trap to reveal that.
Well, maybe. The problem is that mature languages and ecosystems are mature and new features have to be shoehorned in. Raku (https://raku.org) on the other hand is intentionally designed as a braid of sub languages (slangs) for quoting, regex, PEG, etc and you can easily make your own slang with eg. https://raku.land/zef:lizmat/Slangify so you get your DSL as a drop down language in a general PL setting.
There's so many languages out there, I reject Raku out-of-hand simply since IMO the type should follow the variable name.
You mean like:
orhmmm Raku is C style
Very good, I wrote Pascal many years ago, but I was thinking more Kotlin/Scala (right?) vs Java.
> Are Java developers just not as competent as Ruby programmers?
years ago a senior developer close to me said "when screening interviews, if i see rails i throw the resume in the trash"
so ironic how trivial/stupid these language-based judgements are
I would go so far as to say the rise of Rails and the downfall of J2EE being concurrent was not entirely accidental. I have/had no particular affiliation for Rails, but it demonstrated how to write simple, opinionated backend code, and that inspired a flurry of Java/JVM web frameworks that tried to follow a similar pattern and eventually gave us libraries like DropWizard, Javalin, SparkJava, even Spring Boot to some extent.
> years ago a senior developer close to me said
What was the senior's stack?
I’m going to assume Google Docs.
I couple of years ago I would ask to collect your coworker’s garbage bin :)
Not as easy to find in my vicinity, at least good ones, which is of course true for any language and profession in general.
I have RoR on my resume and very fond of it.
If one is looking for Java developers, it only makes sense to throw rails resumes in the trash. It will save time for both parties.
One side of my brain agrees that's a dumb way to judge anyone but then when I think about the accepted filtering mechanism they really aren't any better or any worse. You cannot interview everyone and ultimately you're looking for some combination of competence, alignment, drive and social fit. Filtering on where you worked previously or where you went to school or whether you can pass some coding challenge only partially fills in the matrix. And the size and shape of the organization can drive how much people in the hiring loop look at each data point. This senior engineer's ideal for alignment and social fit probably favored people who think like them or their department's head.
To be fair, years ago Rails was what all the "bootcamp" programmer mills were pushing. Only you have the full context, but absent of that it is likely that Rails was truly found to be associated with poor applicants. Not because of anything about Rails itself, but because of those "bootcamps" not developing quality people. The culling has to occur at some point. If you throw some great developers out with the bathwater, so be it. There isn't enough time in the day to worry about them.
Admittedly, Ruby on Rails makes me think "bootcamp" like you said, and I barely even know what it is.
But shouldn't the check just be that the candidate has used more than one different stack? It's pretty hard for anyone with real experience to stick to one, and even if they do, that's not a good sign either. Or are you saying those bootcamp people end up learning another stack but still not being very good?
> But shouldn't the check just be that the candidate has used more than one different stack?
If you had another filtering mechanism, perhaps you could do that. But what other arbitrary, legally acceptable, filter are you going to use to further narrow the search? Can't realistically throw out all the resumes with female-sounding names, for example. What is going to keep you out of trouble is quite limited.
Why not throw out all the "Rails" resumes? If you had all the time in the world you would interview every last person, of course, but in the real world, with real world constraints, you have to pick a few to interview and live with your choice.
To use the internet's favourite analogy: It's like buying a car. Most people would never find it reasonable to test-drive every single one of them. It is just too time consuming to do that. So, instead, one normally looks at signals to try and distill the choice down to a few cars to test drive. You very well might miss out on what is actually your perfect car by doing that, but if you find one that is good enough, who cares?
On the one hand, that obviously filters out many qualified candidates.
On the other, you only have so much time in the day. It'd take me 3-6 months to give phone screens to every resume that comes in the door for any one engineering role, 8x that for a full 4-hour interview. I have to filter through them somehow if it's my job to hire several people in a month.
You'll obviously start with things that are less controversial: Half of resumes are bot-spam in obvious ways [0]. Half of the remainder can easily be tossed in the circular filing bin by not having anything at all in their resume even remotely related to the core job functions [1].
You're still left with a lot of resumes, more than you're able to phone screen. What do you choose to screen on?
- "Good" schools? I personally see far too much variance in performance to want to use this as a filter, not to mention that you'd be competing even more than normal on salary with FAANG.
- Good grades? This is a better indicator IME for early-career roles, but it's still a fairly weak signal, and you also punish people who had to take time off as a caretaker or who started before they were mature enough or whatever.
- Highest degree attained? I don't know what selection bias causes this since I know a ton of extremely capable PhDs, but if anything I'd just use this to filter out PhDs at the resume screening stage given how many perform poorly in the interviews and then at work if we choose to hire them.
- Gender? Age? ... I know this happens, but please stop.
If there's a strong GitHub profile or something then you can easily pass a person forward to a screen, but it's not fair to just toss the rest of the resumes. They have a list of jobs, skills, and accomplishments, and it's your job to use those as best as possible to figure out if they're likely to come out on top after a round of interviews.
I don't have any comment on rails in particular, but for a low-level ML role there are absolutely skills I don't want to see emphasized too heavily -- not because they're bad, but because there exists some large class of people who have learned those skills and nothing else, and they dominate the candidate pool. I used to give those resumes a chance, and I can't accept 100:1 odds anymore on the phone screen turning into a full interview and hopefully an offer. It's not fair to the candidates, and I don't have time for it either.
And that's ... bad, right? I have some things I do to make it better in some ways (worse in others, but on average trying to save people time and not reject too many qualified candidates) -- pass resumes on to a (brief) written screen instead of outright rejecting them if I think they might have a chance, always give people a phone screen if they write back that I've made a mistake, revisit those filtering rules I've built up from time to time and offer phone screens anwyay, etc -- hiring still sucks on both sides of the fence though.
[0] One of my favorites is when their "experience" includes things like how they've apparently done some hyper-specific task they copy-pasted from the job description (which exists not as a skills requirement but as a description of what their future day-to-day looks like), they did it before we pioneered whatever the tech in question was, they did it at several FAANG companies, and using languages and tools those companies don't use and which didn't exist during their FAANG tenure. Maybe they just used an LLM incorrectly to touch up their resume, but when the only evidence I should interview you is a pack of bold-faced lies I'm not going to give the benefit of the doubt.
[1] And I'm not even talking about requiring specific languages or frameworks, or even having interacted with a database for a database-adjacent role. Those sorts of restrictions can often be too overbearing. Just the basics of "I need you to do complicated math and program some things that won't wake me up at night" and resumes that come in without anything suggesting they've ever done either at any level of proficiency (or even a forward or a cover letter stating why their resume appears bare-bones and they deserve a shot anyway).
Probably the other person's boss was hiring for some generalist role and not a specific thing like low-level ML.
Any language/library needs to communicate in two directions: to the machine and to the people. At the micro-level, machines work with bits, or voltages, or whatever. That's a technological problem, not easy, but tractable in a mechanical sense.
People, on the other hand, work with ideas, metaphors, expressions of intent, etc. If a language/library makes the communication of those things easier/better/faster; if it can be "written down" clearly, and "read" clearly by a person, then does it really matter into which taxonomic category it fits? We pick horses for courses. That seems about right.
If Rails works for you, is complementary with what you want to achieve, is an accelerator, and is generally well-understood by the people with whom you work, then use it. Alternatively, if the answer to all the previous is Stanza then go with that. There's less "right" and "wrong" in those decisions than there is "advance", or "struggle". It sounds trite. But, use what works. If something doesn't work make something that does, iff that's the most efficient approach.
For me the title is a bit of a contradiction: I always think about the library as “the final language”. So author’s example of RoR/Ruby is “RoR is a great web service language that uses Ruby as the base, they evolved together and arguably as RoR is the main source of clients for ruby, ruby was as well designed for RoR as RoR for ruby”
I think about programming/design as languages/translation in a lot of ways: its languages all the way down.
I agree. c# and asp.net core also co-developed. Interestingly in both direction, towards users (tons of type inference, removing boilerplate, ...) and system (writing highly optimized web servers with low level paradigms)
"The more powerful the language, the easier the libraries are to use." for anyone thinking of reading the title without the body
It's true, you couldn't really do Express in Java, at least not back then.
I don't understand, what's Express? As for libraries and Java, I'd argue Java became a well established enterprise language and platform exactly because it makes such highly effective use of libraries.
It's the NodeJS webserver
See C#'s asp.net core minimal apis (a express clone). So it is definitely possible but you need to co-develop the language. I think as you point out.
It’s possible to have something like Express, take a look at Javalin.
But Java problem is not the mechanics, it’s that the community doesn’t want nice things.
Javalin was inspired by https://sparkjava.com/ which was inspired by Sinatra (which I think also inspired Express?).
Anyway, libraries like this were only really feasible after Java 8 because of the reliance on lambdas. Having to instantiate anonymous nested classes for every "function" was a total pain before that.
Kinda now that Java has lambdas, but still async in that disn't work as easily as JS, which is important. This is only recently starting to change with Project Loom.
There is a good web framework for C. It's called PHP. ;)
I think you stretch this library thought a bit too far :)
I agree with the sentiment of this article but the question that fascinates me is "when do you need a language feature instead of a library in order to accomplish X, Y, or Z?"
Well there are really bad languages. Like ABAP or SQL. But even in higher languages like Java, you sometimes loose expressiveness
I have to disagree about the author's described purpose of programming languages. PLs exist to provide elegant expression to a curated subset of ways of expressing solutions to problems.
At the extremes, we call these paradigms. Functional languages, Object Oriented languages, Array languages, etc. But every language exists to make some subset of "shapes" of solutions easier to read and write. Elixir encourages you to describe your programs as a distributed system of programs each running a series of transformations to data, thanks to its pipeline system, and to push your branching to function-call level with its pattern-matching multiple dispatch.
Java encourages you to write your application as a collection of things, that know stuff and do stuff, including telling other things to do stuff based on things they know.
C and Go encourage you to write your programs as an ordered series of atomic tasks for the computer to complete.
SQL has you describe what you want your output to look like.
Etc, etc. There are inherent trade offs between languages, because what you make inelegant to express or even inexpressible carries value, too.
There are a few approaches if you want to write a new language. One, as the author argues, is to write a library in an existing language, which may require sacrificing ergonomics to fit inside the syntax of the host language, but is safe, modular and reusable.
Many DSLs can be bolted onto an existing language with support for compiler extensions. This approach offers more flexibility, but often leads to fragmentation and poor interoperability in the language ecosystem.
There is third approach, established by a group in Minnesota [1], which is to design languages and tools which are modular and extensible from the get-go, so that extensions are more interoperable. They do research on how to make this work using attribute grammars.
If the host language has a sufficiently expressive type system, you can often get away with writing a fluent API [2] or type safe embedded DSL. But designing languages and type systems with good support for meta-programming is also an active area of research. [3, 4]
If none of these options work, the last resort is to start from tabula rasa and write your own parser, compiler, and developer tools. This offers the most flexibility, but requires an enormous amount of engineering, and generally is not recommended in 2026.
[1]: https://melt.cs.umn.edu
[2]: https://arxiv.org/pdf/2211.01473
[3]: https://www.cs.tsukuba.ac.jp/~kam/papers/aplas2016.pdf
[4]: https://arxiv.org/pdf/2404.17065
> If none of these options work, the last resort is to start from tabula rasa and write your own parser, compiler, and developer tools. This offers the most flexibility, but requires an enormous amount of engineering, and generally is not recommended in 2026.
You mean like this?
https://github.com/williamcotton/webpipe
https://github.com/williamcotton/webpipe-lsp
https://github.com/williamcotton/webpipe-js
It's less effort if you, well, you know where I'm going with this...
> There is third approach, established by a group in Minnesota [1], which is to design languages and tools which are modular and extensible from the get-go, so that extensions are more interoperable. They do research on how to make this work using attribute grammars.
MLIR [1] has entered the chat :P
I know I know MLIR is an IR and not a programming language, but MLIR does give me the feeling of "an IR to rule them all" (as long as you're ok with SSA representation), and the IR itself is quite high-level to the point it almost feels like an actual programming language, e.g. you can write a MLIR program that compiles to C using the EmitC dialect that feels a lot like writing C.
[1]: https://mlir.llvm.org
Well some languages, like Mojo, expose MLIR directly in the language as intrisics.
https://arxiv.org/abs/2509.21039
The author makes a good point about language capabilities enabling certain libraries to be written, just as DSL makes it easier to reason about problems and implement solutions with the right kind of abstractions and language ergonomics (usually at the expense of expressivity and flexibility).
There’s a time in my life where I designed languages and wrote compilers. One type of language I’ve always thought about that could be made more approachable to non technical users is an outline-liked language with English like syntaxes and being a DSL, the shape of the outline would be very much fixed and on a guardrail, and can’t express arbitrary instructions like normal programming languages, but an escape hatch (to more expressive language) for advanced users can be provided. An area where this DSL can be used would be common portal admin app generation and workflow automation.
That said, with the advent of AI assistants, I’m not sure if there is still room for my DSL idea.
I mean that's Zapier or n8n?
As a student of philosophy of language, I obviously agree with the author (against the quoted thesis).
The structure of a language matters to the ease and feel of its use, despite even being logically identical. One parallel would be the syntactic benefits of something like Hintikka’s independence-friendly logic vs first order logic, even if they are equivalent.
The sentiment shared is that we should sacrifice benefits to the next generation to make our own lives easier. This is a common sentiment, but a sad one. The goal should be a natural language based programming language, that everyone can use, along side a technical programming language that makes unambiguous the interface between the language and the machine.
Everyone seems to endorse their happy medium, and those languages are also perfectly fine.
> Can we design a language so expressive that library writers can easily write the most appropriate object system, or most appropriate type system, to fit their application?
Why yes, it can and has been done: https://www.dreamsongs.com/Files/ECOOP.pdf
The OP's point is well-taken: a new language usually forces you to change 100% of your environment and tooling, whereas a new library respects your habits and preferences.
I follow new language developments with keen interest, but few of them will ever reach the level of maturity to be considered serious candidates for adoption. It's also risky to adopt a language that you cannot easily hire developers for, for example.
Libraries are great, but there is only so much they can address, and that depends on the language, too, as the article correctly points out. And there are two kinds of libries: tool libraries and frameworks. Someone once said it nicely: "Frameworks are like Hollywood - 'You don't call us, we call you!'". Frameworks often require you to submit to their control flow rather the other way round; that's why I prefer tool libraries.
Agree. I don't know why a statement that uncontroversial got the bums rush.
With a Domain Specific Language (DSL), you parse code and build an abstract syntax tree. But you can also build a Python library where you construct the same tree. With the benefit that LLMs are already better trained on Python code. If you need a deterministic programming language, you could use starlark.
DSL is a term with such fuzzy meaning, I don't like it at all. It's always valid to just say "language". Languages and libraries don't even have to be opposing concepts either. Let's say you write the first ever JSON parsing library. Did you just create a library? Or a language?
I have started gathering DSL specific content over on https://reddit.com/r/domainspecificlangs … there are several definitions over there. Personally I would distinguish between a drop down DSL and a full blown independent language.
Doesn't seem fuzzy to me. JSON parser is a lib.
Logic systems are a good place where the library first approach tends to work well: you keep a small, boring core (the inference engine), and let people extend it with predicates, rules/operators, and domain packages.
I’ve been experimenting with a small defeasible-logic core (argumentation semantics + priorities + conflict detection) that stays stable, while most of the real meaning lives in extension points. https://github.com/canto-lang/canto-lang
I'd say that the best thing ever would be an easy way to call a library written in xxx from a program written in yyyy.
There are lots of libraries already. Instead of rewriting them in every language why make them available to every language.
Yes, I know it would be difficult and in some cases impossible.
Java has Grails web framework. We have designed apps with 75% less resources and time compared to Spring at a big enterprise. But most devs wanted springboot.
Grails requires Groovy, though you can integrate Java classes into a grails app.
Now that we can develop script style with Java 21, I'd like to see something like Grails that worked with Java only...that would be a fun way to develop web apps. I liked Grails, just not Groovy.
Of course, in Lisp, you can implement language features as libraries, which kind of undercuts the point of this article.
> In summary, the purpose of a general-purpose programming language is to enable the creation of powerful and easy-to-use libraries.
Close! The purpose of a general-purpose programming language is to enable the creation of powerful and easy-to-use languages, but often just libraries.
I think this thinking makes sense if you've not used enough programming languages pragmatically.
But, if you squint, great API design is a bit like embedded domain specific language design as well.
I think there's room for both.
Julia got it right with its macro system. You can write embedded DSLs easily.
But they are still worse experience that dedicated, separate languages. Compare ModelingToolkit.jl with Modelica (ok, there are some differences in capacilities, but just compare how better is to express models in Modelica).
> Stanza provides an optional type system, garbage collection, and a multimethod based object system. But if you don't like Stanza's object system, there is no way to write your own. This is one of the main directions of programming language research. Can we design a language so expressive that library writers can easily write the most appropriate object system, or most appropriate type system, to fit their application? Perhaps one day we'll have such a language.
We already have it. It's an obscure little language called C++. Tise interested in those kinds of extensions to a language should look into Herb Sutter's experiments with cppfront: https://hsutter.github.io/cppfront/welcome/overview/
C++ is most definitely not it.
Lisp is what you are after if you want to include some object system as a library, or a new type of switch statement as a library or a new kind of if statement as a library.
C++ can do none of that.
C++26 reflection alongside compile time code execution, and template metaprogramming, can already do a lot.
It is the best way? Probably not, but we seldom get to chose what mainstream languages win out on the field.
C++ can do some of that. Let's say I want an if statement that takes an integer and three blocks of code. It executes the first block if the integer is less than zero, the second if it is zero, and the third if it is positive.
OK, if you squint enough that by "block of code" you mean closure, or function object, then I can write that in C++. I can make the if statement a free-standing function (that is, not a member of a class), and add it to any library I wish.
Now, you can say that it's going to be tedious to use that, because you have to set up three closures every time you want to call this "super if". And you'd be right, but that's a different argument.
One problem is that closures don't actually behave like blocks. Consider that you might want to use this three-legged-if inside a loop. If it's a real statement, then those branches can have `break;` and `continue;` statements which affect the surrounding loop. If those branches are just closures being passed to a function, then they can't.
> OK, if you squint enough that by "block of code" you mean closure, or function object,
But we aren't squinting here; those closures can't perform a return where your `new-if` function is being used, they can't perform a `return` like a proper `if` can, you can't goto, or break or continue.
It's just a function taking functions, with all the restrictions that that entails.
How can you declare new syntax in C++? Wouldn't it just be a function call?
Yes, a function call. Not new syntax. But as a function, it would be trivial to add to a library.
My point was that you can often get the effect you want with no new syntax. (Cue 10,000 replies that state "but you can't get this effect without new syntax!" Perhaps not. Many of those tend to be rather contrived, though. I'm more sympathetic to the argument that new syntax would make something less clumsy. If it's something you need to do a lot, that matters.)
Yes - I see what you mean. There are degrees of ease of use at between - at the extremes - what writing assembly provides, which technically can do it too, and what something like, say, Haskell provides. C++ is of course closer to Haskell than Assembly, but there's still quite a headache in using your solution that is down to absent C++ language features.
You can always use macros! Just look at how beautiful and elegant and easy to learn and transparent to debug the Microsoft C++ MFC COM/OLE/IDispatch/ActiveX object system macrology is. /s
https://learn.microsoft.com/en-us/cpp/mfc/tn038-mfc-ole-iunk...
Rails wouldn't exist without Ruby, Ruby wouldn't exist without C, Rails can't be rewritten in C, Rails isn't a library.
But aren't Rails, Laravel and Django a bit similar? At least for the people not directly involved in coding.
> Rails can't be rewritten in C
It could if you added message passing to C.
Which we have, and DHH admits that Rails took directly from that. Rails is (loosely) a rewrite of what was originally written in C [with extensions].
> Rails is (loosely) a rewrite of what was originally written in C [with extensions].
Are you talking about WebObjects, which was written in Objective-C? (1) If so your comment is somewhat tangential to the truth.
(1 2104) https://news.ycombinator.com/item?id=8765009
The problem is really that sometimes making something feel ergonomic in a language can be a pain.
Although that in itself might be a hint to change language and write your library there, instead of inventing a new one.
it's strange cause for some devs (lispers, smalltalkers, forth..ists), the language is the core, and any concept is to become a generic linguistic trait (and everything will be build by composing expressions with these traits).
yet at the same time, clojurists love the idea of doing lots of dsl libraries..
i think that languages is are for worlds and libraries are for adding ships, planes and cars to that worlds, enabling those worlds itself.
the key is that not all worlds enable the same kinds of libraries.
- i need a language that looks like typed python
- and runs 50 times faster than c, c++, rust and zig
- comes with a standard library covering 50000 use cases
- has direct integrations with drivers to every major database, crm, analytics provider, key value store, queue systems
The article seems to vibe railing against Java.
Nothing wrong with that. Log4shell should have been the end of everyone using Java.
There is this little mobile phone platform out there.
It has moved to Kotlin, which is what Java should be. With a custom VM. And even now, Google is moving to Fuschia which is Dart based.
Libraries and languages are not actually about syntax or function. They are communities first. They each have a community of users and one of developers. Depending on their application they each attract very different people - which is wonderful.
The work matters too of course. Frequently used functions should be categorically bagged into libs and if the lib is used often enough some of it's functionality should be baked into the language. If languages require something often enough the language layer above should provide it and if things are frequently needed close to the metal it should be baked in hardware. Possibly as a co-processor and then as part of the cpu. We should even have a similar process moving things in the other direction. I cant wait for the day when floating-point arithmetic becomes a library complete with a community of people who still think it's wonderful. Like a football channel to cleanly contain that kind of undesirable materials. Some libraries/modules/frameworks should also be replaced by competent developers. We don't want a leftpad community.
I don't know ruby or rails so probably wrong on this but why does the author say no framework for Java web. How different is Spring from that?
They talk about the programmer which doesn't know neither cares about the language stuff. So what is Spring lacking from that perspective?
"Java is a DSL for taking large XML files and converting them to stack traces"
"XML is like violence. If it doesn't solve your problem, you're not using enough of it."
XML is like a flyer saying "do violence" maybe, it doesn't do anything by itself.
That excuse worked for Trump on January 6.
> “Stop Designing Languages. Write Libraries Instead” (2016)
It looks that somebody listened. We now have 3 GTK libraries in a system, a lot of graphics libraries (cairo, etc) 3d libraries (Mesa, vulkan). It is a mess.
Lots of languages could just be implemented with classes in C++. Every "probabilistic language" could just be types that interact with each other properly.
I think I mostly agree with the thesis here, but I actually liked the point in the title at face value, too. We need both, I think. I guess I'll be another annoying Lisp guy, but:
> At this point, the right question to ask would be, well can you write a static-typing library for Scheme that then automatically checks your code for type errors? And the current answer, for now and for the foreseeable future, is no. No mainstream language today allows you to write a library to extend its type system.
The author seems to provide a counter example themselves(?):
> Racket and Shen provide mechanisms for extending their type systems...
I wonder if this is as clear-cut as the author is making it out to be. Coalton, which is effectively a library (and language) for Common Lisp, seems like it basically does this. Maybe that's not exactly what the author is referring to, because it is essentially a new language on top of Lisp using its meta-programming facilities, as opposed to merely extending the type system. Still, it can be used as a library right alongside Lisp code, so I think it's in the same spirit of of the first question of writing a "static-typing library that automatically checks your code" in a dynamic language.
Standard scheme may or may not be able to do this, but most Scheme implementations have unhygienic macros like CL's too, so I'd assume something similar would be possible. The fact that that these tend to be extensions from implementation designers might align with the article's point though. Also somewhat to the author's point, Coalton does rely strongly on CL's underlying type system, for which there's no real equivalent in Scheme. It also relies on implementation-specific optimizations alongside that.
For what it's worth you can (and indeed people have) written object systems in Scheme, despite the language not having one, though they tend not to be performant, which is likely another point towards using/writing a different language. CL also tends to allow fairly deep extension of its object system through the Meta-object Protocol.
I guess my point is that in my (probably biased) opinion, Lisps, or other languages with very strong meta-programming facilities, are pretty close to the language longed for in "Perhaps one day we'll have such a language." They aren't a silver bullet, of course. CL has no easy way to write performant coroutines/continuations, for example, even given all its extensibility. Scheme has no real type system, etc. etc.
I don't think any of this invalidates the articles points, I'm just not sure I agree with the absolutes.
> But thanks to Ruby on Rails, he doesn't have to! So he said that he has no particular opinion about the Ruby programming language, but he absolutely loves Rails.
Ruby got a hype phase with regards to rails. It then dropped. A lot.
TIOBE, while it is in general crap, is somewhat accurate when you plot things over time:
https://www.tiobe.com/tiobe-index/ruby/
So, ruby peaked with rails between 2006 to 2009 or so, give or take. Then the decline phase set in, and now it is unfortunately also crawling behind perl into extinction. This is very unfortunate - I still use ruby almost daily as the ultimate glue language. But this can not be denied now that ruby is following the extinction path perl already had going some years before.
I was using ruby before rails was created and ruby covers all my web-needs. I had a web-framework in PHP, used it for about three years, ported it into ruby and expanded it massively in the last 20 years or so (well, almost 20 years). I retired from rubygems.org when RubyCentral got crazy in 2024 (and even crazier in 2025 with the mass purge of developers). So, one difference here is that the friend he talks about is using a specific framework. He probably no longer uses ruby nor rails. I use ruby because the language is very well designed and covers (most of my) use cases; the rest I may sprinkle down with java. So whether rails exists or not, makes zero difference to me. Actually without rails it would be better, because people using ruby would be using it because of ... ruby. Even if there are then fewer users. I still think this is better than those who will jump ship anyway because they only use ruby due to rails. These guys are not like in the same boat. They have use cases for getting work done via rails, designing websites, infrastructure related to websites, user-interaction and so forth. But they don't really use ruby as such. Their use case is quite limited. I think this is one of the biggest problems here. It in part explains why ruby dropped down a lot (there are many reasons for this, python being so successful is in my opinion the biggest reason, but the other smaller reasons also add up - that also includes the laughable joke that is documentation in the whole ruby ecosystem. That's inexcusable - note, I am not saying documentation must be perfect, but please look at opal, ruby-wasm or rack - the documentation there is virtually NOT EXISTING.)
> The vast majority of programmers are non-experts, like himself
No, I think he is an expert - just in a specific niche and field. Not all experts know everything equally well.
> Subtle language features like first-class functions, and object systems, are lost on them because they don't really use them anyway.
I don't think this is true. Some language features are very useful. Ruby's blocks for instance. They are probably one of the top three win-win features ruby offers.
> Computer scientists should really be spending their time developing new libraries rather than inventing new programming languages.
I also disagree here. I would, however had, say, that new languages should be well-designed. Many new languages suck. Old languages also suck. Designing a great language is very hard. If it is just a toy or research language then this is fine, but once a language is meant to be "real", it really needs to have compelling use cases and be great in many areas including documentation.
> These features are simply not available in all other languages. Java's meta-programming features, for example, are just not powerful enough to implement a system like ActiveRecords. Rails is only possible because of Ruby.
That's also incorrect. You can create any DSL as you like in Java too. Ruby just makes this a lot easier out of the box. Plus, you can also have great websites without rails.
> Ruby on Rails was designed to make it possible to build websites without understanding type theory, or memory management, or object-oriented design patterns.
Ok so ... why would this not be possible in Java? Why would he have to write Java code for a library to be used in this regard?
> Ruby on Rails provides a concise way for expressing: do this when the button is clicked
But you have the same in many other languages and frameworks too. I mean this is how PHP was started initially.
> The "do this" part is implemented in Ruby as a first-class function. How would it be implemented in languages like Java which don't support them?
Write a solid DSL.
> The programming language directly shapes the design of its libraries.
If this were true, why would GTK have glib+vala? I mean, they could just rely on C directly, right?
Besides, ruby is just a wrapper over C really.
> The more powerful the language, the easier the libraries are to use.
That part is true. A better designed language makes for better libraries or a chance to have better libraries. I noticed this when I compared my PHP code to my ruby code. I am not a good programmer, but my ruby code is much better on every level than the equivalent PHP code. Fewer lines too. While this also has to do with experience, at the end of the day PHP is simply a much worse language than Ruby is. At some point I decided I don't want to invest into languages that suck when I could be using better languages instead. That is also why I stopped writing shell scripts - it is just a waste of time having them.
Rails is also, by the way, fairly well documented. So I am not saying all in ruby has horrible documentation of course.
> now it is unfortunately also crawling behind perl into extinction. This is very unfortunate - I still use ruby almost daily as the ultimate glue language. But this can not be denied now that ruby is following the extinction path perl already had going some years before.
I'm pretty sure that can be denied.
Rails and Ruby (both separately and as a unit) is still absolutely huge. It's launching massive new releases regularly and still underpins a healthy chunk of the top websites on the planet (Shopify, GitHub, Airbnb, Twitch, Hulu, Kickstarter, Zendesk, Basecamp, Crunchbase, Dribbble etc etc) and is still taught to new developers as well.
The quotation marks having been stripped from the title changes the meaning quite a bit…
I admit the article is not what I at first expected. But I liked it. The references to Ruby feel dated, though.
I know that HN is famously a discussion forum where users comment based on the titles of submitted articles, rather than their content.
With that said, the divergence in comments on this very insightful and well written article will soon provide an unusually clear means of determining who is commenting on the title and who is commenting on the article.
The omission of quotations in the title triggered my Lisp-damaged brain to man the walls, only to immediately be met with Ruby and Scheme examples. False alarm.
That's fair. It's also the case that to some extent HN's article titles serve the same purpose as that one line description in a speed dating event. They're ice breakers, everybody has the same prompt and then writes about that, and even if they did read the article which I agree often they don't, they come at it from a different angle.
I feel similarly to the article author, it is trivially true that we could express anything in all the general purpose languages, that's what general purpose even means, but I find for Computer Languages the Weak Sapir-Whorf Hypothesis checks out pretty well. The language changes how you think about the problem.
As a long-time HN contributor, I believe in visualizing myself like water flowing downhill. As such, I certainly would never try to overturn the prevailing culture of commenting on article titles and in fact engaging in it myself from time to time.
I will not. I refuse
Yes! This is also why I think it's stupid that languages are now trying to kill their most popular libraries as a matter of principle.
E.g. node says "oh no, you need a library to write tests!" and now that means that you have to have a testing framework built into your runtime. And of course it's just another library, really, that competes with the original one, but this one is blessed with standards so it has a monopolistic advantage that will deter further innovation.
> And of course it's just another library, really, that competes with the original one, but this one is blessed with standards so it has a monopolistic advantage that will deter further innovation.
It's called convenience. You're free to create a testing library so good that it'll knock socks off the stdlib one.
My question is so simple: why is a level playing field seen as bad now?
Have we given up on having a market economy? You can't have a fair game when one team playing is also the referee. Yet everywhere I look that's the way of it. Apple runs the app store so that they can also ensures that every successful app is theirs. The supermarket stocks the shelves, but also uses their position of power to kill successful independent brands. Node takes libraries which have taken years of work and shits out builtins with at most a week invested.
I think it's a national embarrassment: anticompetition to the point of communism held up as if it were the genuine spirit of the American Dream.
> Node takes libraries which have taken years of work and shits out builtins with at most a week invested.
> I think it's a national embarrassment: anticompetition to the point of communism held up as if it were the genuine spirit of the American Dream.
You think including a testing library in a language implementation or standard tooling is tantamount to communism?
Yes, I think it's taking several steps on the path away from individual creativity towards society-wide approved ideas.
I completely disagree with the post.
All programming languages are equivalent meaning their level of expressiveness is the same, it's not an opinion it's a fact. Each language comes with its runtime and its peculiarities but potentially you can always make any feature that another language runtime has with any language, even though probably not with the same performance and efficiency has been that feature native to the runtime itself.
So there are no "more powerful languages" just runtimes that allow you to hide away some stuff considered stable enough that they become some kind of primitive for the programmer, now we may have different opinions on what elegant code is, but personally I'd like to avoid code that directly (i.e. no kind of abstraction) relies on runtime features and instead express clearly my intention in code, but I recognize the productivity gains.
You may be thinking of turing completeness. All turing complete languages can compute the same functions. And in that way they are equivalent.
However, not all languages are turing complete. See, for example, charity: https://github.com/dobesv/charity
Furthermore, turing completeness says nothing about expressiveness or capability. Imagine a language that has no IO. Such a language would be able to compute any function any other language can but not do anything viewable by the rest of the world. So obviously not equivalent.
And w.r.t. expressiveness, there is some academic research into how to quantify that: https://www2.ccs.neu.edu/racket/pubs/scp91-felleisen.pdf
I understand and agree, what I was trying to say is that one should not confine ones thinking by the constraints of a tool, would it be a programming language or whole framework, but to express everything as freely as possible without details of implementation only then one can go deeper and add concreteness that brings its set of constraints and all of this should be possible in any programming languages.
I hope I've cleared my standpoint.
Are you familiar with https://paulgraham.com/avg.html?
No I wasn't, it was a really interesting read thank you, but that blog post seem to me like an argument for me not the OP point of view, because if you refuse to understand how things work by blindly delegating to libraries and frameworks (like RoR) you become a "Blub" programmer that thinks in the way of constructs and decisions that the library/framework authors made.
It does directly address your claim that there do not exist "more powerful languages."
Yeah I can see that, but that lisp feature is not exclusive to lisp, if you know what you want and what you are doing you can implement the very same thing in any other language, you may say it is convenient that lisp already has it, but it does not make it more powerful. I don't know list, but there will surely be something that is missing from it that another language has it, now I ask you which is more powerful? See? Everything is relative to what you want to do. The very author of the blog you shared is falling in the same set of programmers he wants to criticize because now he thinks in lisp macro and the very moment he cannot use lisp, he will feel lost but has he stopped and thought that what he needed was something to manipulate code at compile time he could have used any language
I just came across a situation where I had a DSL but it was clear that a language would have been better. What I don't like about this is the dogmatic tone which is pretty common in IT. Don't to it that way, do it my way! Sometimes a DSL is a solid choice, sometimes a language is a better one, sometimes you might want to support both but I guess "Choose the right abstraction for your domain" doesn't make for a clickbait title.
It's not clear what you're trying to say, because the "L" in DSL is "Language".
All programming languages are domain specific, so presumably he is referring to English (or another natural language of the same nature). Meaning that he must be saying that sometimes letting the vibes flow is best.
No, I meant a General Purpose Language (GPL) or actually this was an application specific language. You don't need to be so pedantic. Yes, the L is for language but the idea of a DSL is not well defined but these remarks reinforce my argument that people are too dogmatic.
I wasn't trying to be dogmatic, I was genuinely trying to understand what you were trying to say, because it didn't seem to relate to languages vs libraries, and I found it confusing.
Languages are "Easy" to design. There is nothing wrong designing a new language and it can be fun.
There is however something wrong with releasing your new language! In most cases you should show it off to close friends, or your professor, and then burn it and all the source. Sure you might be better than the current language, but you won't be enough better as to be worth it. (even if the language is notoriously bad C++ where it is easy to be better - you won't be enough better as to be worth it).
If you want a better language there are two good options: switch to a different one that already exists; or make your language better. There are lots of great choices for languages out there if you want to switch. If the language you are thinking of doesn't have an active community of people working on making it better, it probably isn't a good choice.
Whichever language you choose though, libraries are the hard part. There are a lot of bad libraries, we need someone to write a better one - but only if one doesn't exist! For the great libraries out there, most need someone to contribute.
A large part of libraries is the consistent interface. Often there is a great libFoo and libBar, but their APIs are not consistent and so we need a libBarWithFooStyleInterface, and/or libFooWithBarStyleInterface. Better yet, we need everyone to come together and agree on how the interface should be and then make both use that new standard - cleaning Augean stables with a toothbrush seems like an easier task. Of course in the real world there a hundreds of libraries each with a great interface that is not consistent with the others.
> then burn it and all the source
Nah, don't do that. You will enjoy looking back at it in your old age. I wish I had all my old code now.
fare enough. So long as you don't inflict it on the world as something they might really use it is fine.