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Comment by chuwy | Hacker News Reader

I agree about painful learning curve for Scala. Problem I think in very divergent community and in different approaches for a every single problem (unlike for example Python or Go): OOP vs FP, Typesafe vs Typelevel, scalaz vs cats, Cake Pattern vs sanity.

There's a also a problem that most powerful Scala techniques are there "by accident" [1] and unlikely will (or should) appear in official guides.

Also I disagree that "Scala for impatient" is good book for start. It make me feel Scala is dump of random unrelated features, it's very easy to disappoint.

However, despite all above I think Scala is definitely worth to invest some time. It made all other learning curves (for languages, techniques, concepts) more flatten.

[1] https://meta.plasm.us/posts/2015/07/11/roll-your-own-scala/

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The community is the worst part IMO, and it all boils down to the Typesafe vs Typelevel communities. The typelevel crowd want to turn Scala into Haskell whereas the typesafe crowd have always recognized it as an ML dialect first and foremost.

The rift pollutes and bloats your dependencies, and causes problems with unexpected behavior and unreadable documentation. Trying to shoehorn libraries into my projects that pollute their code with these new standard libraries with lazy functionality and its accompanying monadic bullshit[1] is a huge thorn in my side. I wish the typelevel crowd would just accept the fact that Scala is an ML language, and adopt Frege instead if they can't handle that.

[1] https://existentialtype.wordpress.com/2011/05/01/of-course-m...

You are talking from the point of view of an advanced I-know-about-this-stuff annoyance level.

Newbies to Scala, especially those coming from Java, couldn't care less whether it looks more like ML or like Haskell. Both languages would be alien to them. Robert Harper's "Existential Type" blog is hardly aimed at the average programmer.

I'm pretty sure this is not the worst part about Scala :)

I find that the Typesafe (Lightbend) and Typelevel communities are more or less moving in the same direction. Using Shapeless, for example, doesn't seem to really conflict with more mundane Scala usage. I'd say that there's more of a contrast with the Scalaz world, where obscure category-theoretic terms and operators are unavaoidable.

That said, I've had plenty of success applying Scala at work without bringing in overt category theoretical concepts into my codebases. Scalaz remains very much an opt-in community.

> It made all other learning curves (for languages, techniques, concepts) more flatten.

I find learning Haskell definitely does this and although I can't do the same things in C# a lot of the ideals (immutable state, keeping things separate and simple as possible) not having a complex unpredictable state to manage with lots of 'actors' trying to mangle with it.

Haskell has design patterns which are only what in the OO GoF context you couldn't even dream of. The free monad interpreter pattern alone can probably achieve what all of the other patterns do and then a few more light years. It is amazing stuff and to bring a single drop of this greatness back to the mortgage-paying languages is nice to do. Rx anyone?

I'm aware it's probably not intentional, but you describe Scala as being eclectic, and then immediately criticize Scala For The Impatient for presenting it as eclectic!

However, I do feel like you're right. For instance, the section on XML literals probably should have been avoided, since that feature doesn't fit nicely with the rest of the language and most of the time isn't necessary to know.

I think that's totally consistent. It's bad that Scala is so eclectic. It's also bad that introductory books present Scala as eclectic instead of selecting the "best" subset of Scala to teach.

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