Ask HN: Functional programming in Kotlin vs. Scala advantages/disadvantages? | Hacker News Reader

Ask HN: Functional programming in Kotlin vs. Scala advantages/disadvantages?

14 points4ipp10 comments

I am curious if there are any advantages or disadvantages in the are of functional programming comparing Scala and Kotlin. Are there any important functional features that one has and the other doesn't?

View on HN

I think the main differences Scala being much more of a functional programming language where as Kotlin is a bit of a balance between Java/OOP and FP and affects the complexity/learning curve of the respective languages.

OVERVIEW - Scala is much more of a functional programming language - Scala has a steeper learning curve - Scala community/ecosystem leans much more towards FP - Kotlin is like Functional Programming "lite"

LANGUAGE - Scala: has higher kinded types - Scala: has for comprehensions - Scala: has type classes - Scala: has built in support for monads - Scala: has better support for encoding errors at compile time

MARKET - Kotlin: has heavy usage on Android - Kotlin: on the server side is pretty active too - Kotlin: integrates nicely with java - Kotlin: multi-platform support

Choosing Scala with the intent of only using the simpler parts isn't a path I've seen work out. Maybe with strong dev culture, documentation, and tooling that could work. My experience has been that you end up with more complex implementations than you wish you had to maintain. The other way to go is to hire for it--so everyone is competent and comfortable with that level, at which point it's typically not the subset. With that view I would only suggest Scala over say F# or OCaml if JVM compatibility was a requirement.

It's fine, actually. I've been working many teams over the last eight years using Scala. The important thing is to know where you _don't_ want to go and you'll be fine. Clean code is a developer's agreement.

> My experience has been that you end up with more complex implementations than you wish you had to maintain.

Don't you get that with any language? I for one always find myself in a battle against complexity, no matter the language.

There is a difference. The advanced Scala one may be simpler in concept if the high level concepts/idioms are known and a complete mystery if not. With less expressive languages the complexity is due to the volume rather than nature of code if that makes it any clearer.

Metaprogramming or code generation is similar. You can certainly make smaller, more sophisticated solutions with it. I would consider that has a comprehensibility cost and need some justification for its use, if not merely for academic/learning purposes. Maintainability could go either way depending on the situation and team composition.

Scala is a much more functional language than Kotlin. Scala has inbuilt support for constructs like monads etc. Kotlin needs library like Arrow.

Thank you. Are there other benefits apart from build in monads support?

Big thing with scala is you really need someone who knows what theyre doing. The language is powerful and complex, which allows developers to shoot themselves in the foot. A big project, with all first time scala developers, will turn into somewhat of a maintenance nightmare. Generally at the outset, it needs to be determined what the best practices and design patterns will be.

If you're looking to stay in the world of JVM and want something functional, enjoyable, and a little different, check out Clojure.

Thank you. I am just curious to compare these two. Clojure is a whole different language (as I understand it), while Kotlin and Scala are more or less of the same league.

Fair enough. If it's strictly either/or and your interest is in getting exposure to Functional Programming, then go with Scala for sure.

Reply on news.ycombinator.com