Hacker News Board Hacker News, browsed like a classic message board
Live data from Hacker News

From First Principles: Why Scala?

lihaoyi.com

Post reply on HN
Print view View original

91–100 of 342 posts

Re: From First Principles: Why Scala?

#91

Post by yw3410 »

bsg75 wrote: post #21
adenozine wrote: post #3

If I've said it once I've said it a thousand times: the day Scala kills sbt officially will be the day thousands of devs consider a return to it. Until then, I couldn't dare.

For new Scala devs, how much of a challenge is it to avoid sbt? Especially for those coming from languages like Python and Go, where the former has no build system (ignoring setup.py), or an almost universal one (go build, sometimes make). All of the projects I have touched are documented using sbt, and transitioning the build process for existing code projects while a new language learner is a double cognitive load.

It's easy; there's mill, maven and fury. Mill is quite good - but I've had to dive into the source code a few times to do things.

If you're dealing with dependencies only, then it's a straightforward change. OTOH I've never had an issue with SBT since it's cleanup a couple of years back so YMMV.

Re: From First Principles: Why Scala?

#92

Post by yw3410 »

mark_l_watson wrote: post #7
agbell wrote: post #4

Great Analysis! I agree that languages are becoming more like Scala. I'm not sure about the JIT part though. Aren't many of the recent language success stories now about AOT compiled languages like Go, Rust and Swift?

I am working on an AI book using Swift. Yesterday in a meeting, my manager was asking why Swift. I compared it to Scala, but built on LLVM, and a rich CoreML and other library infrastructure. REPL + closures, very fast build times. I haven’t had much opportunity to use Scala, but I did take Martin’s Functional Programming with Scala course years ago, and that was great.

Complete aside, but how is Swift these days? I used it literally a week after release and promptly stopped because the compiler kept segfaulting - I imagine it's more stable now?

Re: From First Principles: Why Scala?

#93

Post by runT1ME »

dominotw wrote: post #40
MrPowers wrote: post #36

I am a Scala programmer & think it's a great language. Here are some arguments for why not Scala: * Li's libs (os-lib, upickle, utest) have clean public interfaces, but most Scala ecosystem libs are hard to use, see the JSON alternatives for examples: https://www.lihaoyi.com/post/uJsonfastflexibleandintuitiveJS... * The Mill build tool looks a lot better than SBT, but seems like everyone is still using SBT * Scala mi…

> Hard to win technical arguments with Scala geniuses that like using complicated language features. I was on a team building good old crud apps using monads, monoids, categories, combinators, effects cats, seamless and bunch of other nonsense that i've now purged from my brain. You could've easily mistaken our team for a programming language research group at a university. This is literally the number one reason i w…

>I was on a team building good old crud apps using monads, monoids, categories

Here's the thing, if you look at a basic Spring crud app, you are also using Monads, Monoids, Categories, Traverse, etc. but you aren't expressing it in the type system. Seriously go look at modern Spring's flux stuff, it's all there minus the type classes.

I've seen teams that tried to over engineer Spring, teams that tried to over engineer Node applications, and yes there are teams that over engineer Functional style Scala.

All the teams I worked with (and managed) at Verizon leaned pretty heavily into FP style Scala without much over engineering and the experience was extremely pleasant. The only production issues in my three years there I remember were performance related, finding out how to get more throughput or lower latency out of FP Scala. I literally can't remember any 'bugs' that made it to production.

Re: From First Principles: Why Scala?

#94

Post by MrPowers »

bcrosby95 wrote: post #89
MrPowers wrote: post #50

Earlier quoted context omitted.

In the Spark world, you can use a tiny subset of the Scala features and enjoy huge productivity gains over the other language APIs (Java & Python). Those productivity gains are wiped out as more crazy language features get used. I don't think the super complex language features should be removed. Li's libs do some crazy stuff under the hood, but provide a clean, Python-like public interface. Most devs aren't that goo…

> Lots of folks would love Scala codebases that only use 10% of the available language features and none of the complex frameworks. But, like you mentioned, it's a hard language to use responsibly. Does this have the same problem in large languages such as C++ though? Where everyone thinks there's an optimal subset of the language, but no one agrees on what that optimal subset is?

Yep, there is even a talk on the Scala Infinity War which argues for one subset version of Scala that it needs in order to survive: https://www.youtube.com/watch?v=v8IQ-X2HkGE&ab_channel=Scala...

For me, Scala is a multi-paradigm language with tons of features. The community just needs different types of style guides for different apps. vars are horrifying for the functional crowd, but cool with me for example.

Re: From First Principles: Why Scala?

#95

Post by Kototama »

yw3410 wrote: post #81
dkarl wrote: post #74

Earlier quoted context omitted.

I'm on exactly that kind of team now. They've been working on a very simple problem for several years now and have an enormous, sophisticated, but still buggy and unstable solution. They're really smart people, and they had to be extremely capable programmers to get this far, but the embarrassing question is, how would a team of mediocre developers have tackled this problem? They would have picked a mediocre language…

I am continually perplexed at the swallowing of exceptions in certain FP communities. Result types, Either et cetera make it extremely easy to swallow errors by flatMapping thoughtlessly losing the context of where they were - you typically /want/ the call stack when you hit into an exceptional flow.

It makes the code impure (that is with side-effects). One can also argue that if you can encode the potential errors in the type they are not exceptional.

It's not that bad though, because you get much less of these kind of errors than in a typical Java program (for example).

Re: From First Principles: Why Scala?

#96

Post by neysofu »

atbpaca wrote: post #44

I think that the Scala experience will get even better with Scala 3, tons of well thought refactorings for metaprogramming and typeclasses, among others. Also, looking forward to (optional) indentation based syntax.

It's funny, because my experience is almost the opposite. My Scala skills are a bit rusty at this point and I promised myself to get back in the game once Scala 3 was released. Most of it I like. The new syntax, however, is really putting me off. My #1 problem with Scala has always been its huge upfront complexity and the quality of libraries, which are often over-engineered and not nearly enough UX-centric (cough implicits everywhere). Scala 3 was supposed to be a breath of fresh air, but I don't want to invest more time in a language that instead of getting simpler further complicates something as basic as the syntax. This change tells me that I strongly disagree with the core leadership when it comes to the future of Scala and what kind of language it should be.

Re: From First Principles: Why Scala?

#97

Post by noisy_boy »

MrPowers wrote: post #50
dominotw wrote: post #40

Earlier quoted context omitted.

> Hard to win technical arguments with Scala geniuses that like using complicated language features. I was on a team building good old crud apps using monads, monoids, categories, combinators, effects cats, seamless and bunch of other nonsense that i've now purged from my brain. You could've easily mistaken our team for a programming language research group at a university. This is literally the number one reason i w…

In the Spark world, you can use a tiny subset of the Scala features and enjoy huge productivity gains over the other language APIs (Java & Python). Those productivity gains are wiped out as more crazy language features get used. I don't think the super complex language features should be removed. Li's libs do some crazy stuff under the hood, but provide a clean, Python-like public interface. Most devs aren't that goo…

I think the trick to using Scala is to read the high level/key features of the language (case classes/pattern matching/using Option/Some/None, type aliases etc) and basically stick to them. A good yardstick for what are those features is the Scala Book[0]. This is what I read before I started to actually code in Scala.

That coupled with side-effect free functional style (as much possible without overstretching) uses the power of Scala and keeps the code concise and readable. That is how I use it and find it very pleasurable to write in Scala compared to Java.

[0]: https://docs.scala-lang.org/overviews/scala-book/introductio...

Re: From First Principles: Why Scala?

#98

Post by sdfhbdf »

polote wrote: post #78

Damn, you submitted the link 5 times in 5 days, at what number did you plan to stop? https://news.ycombinator.com/submitted?id=lihaoyi

I guess 8.

They did that with a YouTube link sometime before [1]. Stopped after 8 failed submissions.

[1]: https://news.ycombinator.com/item?id=23810499

Re: From First Principles: Why Scala?

#99

Post by sdfhbdf »

aynyc wrote: post #15

Is Scala used outside of Spark and Akka? Spark is my company chosen analytic engine, Scala was/is the main language for majority of the production workload. In the last two years or so, more devs are writing PySpark and SparkSQL jobs than Scala.

It's used in my workplace for ElasticSearch interactions. It's for search, product recommendations, discovery, sorting in an ecommerce.

Re: From First Principles: Why Scala?

#100

Post by Kototama »

brainzap wrote: post #85
dominotw wrote: post #40

Earlier quoted context omitted.

> Hard to win technical arguments with Scala geniuses that like using complicated language features. I was on a team building good old crud apps using monads, monoids, categories, combinators, effects cats, seamless and bunch of other nonsense that i've now purged from my brain. You could've easily mistaken our team for a programming language research group at a university. This is literally the number one reason i w…

Clojure still sounds like research group to me.

Tell that to Amazon, Apple, Netflix, Cognitect and all enterprises that produce reliable and performant software with it everyday.
Post reply on HN