Hacker News Reader

Comment by EdwardDiego | Hacker News Reader

Ah, F#, when I was desperately trying to get skills in .NET (lots of .NET in my town, and I don't have a degree) I encountered F# and lost my enthusiasm for C#. Which is doubly ironic now that I work for a JVM shop.

I still have a lot of love for it though. Especially things like measure types.

View on HN

JVM has a lot of functional languages. As well as the usual Clojure, Scala, etc. I think it has some Haskell-like ones.

Is there an ML on the JVM? The best part of F# is it felt like a simpler version of Scala, even without things like higher kinded types that are present in OCaml.

If you squint very (very) hard, Kotlin can fill that role. You've got algebraic data types via sealed classes, a weaker form of pattern matching via `when` expressions, and decent facilities for higher-order functions.

I was going to comment the same thing. I moved from F# to kotlin and have about 80% of what I want / used from F#. With more tools eco system that makes management happy. Arrow adds to that, with it's library and compiler additions.

I have also been building type providers in Kotlin. Where a gradle plugin scans a file / schema then generates types and DSLs off of it. It's a pragmatic functional language.

The biggest catch to me. Is there are very few places using Kotlin in a fully functional style. On the back end more often than not you'll find Spring. Which undoes a lot of these features / patterns.

Incidentally, Java is getting pattern matching that is more capable than Kotlin's (and probably on par with Scala's).

It’s not exactly ML, but there is a pretty-ok port of Haskell to the JVM called Eta [0].

[0] https://eta-lang.org/

Nah there isn't, I looked. There's Scala, but I don't have 5 years lying around to get up to speed on it.

Frege is a Haskell inspired language on the JVM, about as close as I’ve found.

> I think it has some Haskell-like ones.

Eta might be what you're referring to: https://eta-lang.org/

(there's also Frege, but it's less haskell-y)

Could F# be ported to JVM?

Not until JVM supports value types, low level pointer manipulation and reiffed generics.

In addition to that, the .NET runtime supports tail calls but the JVM does not, IIRC.

Yes, JVM still has it under "some day it would be nice".

Actually this is one of the bytecodes that .NET Native doesn't handle, if I am not mistaken.

2 out of 3 of those are coming in Valhalla. You don't need pointers.

If you want to support F# without performance degradation emulating features, I am not so certain.

Yes, but it wouldn't be F#. F# is so deeply tied to .NET semantics that you'd have a very different language, even if the syntax looked the same.

JVM has already got clojure, scala and kotlin.

Reply on news.ycombinator.com