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

Ask HN: Has anyone here programmed in Kotlin? What do you think about it?

news.ycombinator.com

Post reply on HN
Print view View original

111–120 of 203 posts

Re: Ask HN: Has anyone here programmed in Kotlin? What do you think about it?

#111

Post by drdeca »

rattray wrote: post #104
tootie wrote: post #100

Earlier quoted context omitted.

I think that calling something verbose and unreadable is an oxymoron. XML is very explicit about what each field is labeled. Having an XSD means you always know what field is available where and what type of values are permitted. BUT, if you're still not happy, there's always polyglot maven[1] [1] https://github.com/takari/polyglot-maven

Why why why do do do you you you think think think that that that a a a language language language that that that was was was verbose verbose verbose could could could not not not also also also be be be unreadable unreadable unreadable ? ? ?

It took me until the question marks to realize that the words were repeated.

Weird.

Re: Ask HN: Has anyone here programmed in Kotlin? What do you think about it?

#112

Post by mike_hearn »

radlad wrote: post #90
georgemcbay wrote: post #59

Earlier quoted context omitted.

"I think that at one point go is going to become the defacto language for Android since google likes to keep everything in-house." As someone who writes Android/Java code for the day job but who prefers coding in Go whenever I have the chance, I'd love for this happen but I doubt it will anytime in the foreseeable future. There's just way too much invested in all of the Android Java Platform/UI/etc APIs which would m…

I had kinda hoped that the lawsuit over Java APIs would give them motivation to switch to Golang. :(

I hope not. There are plenty of people who would rather use even Java 6 than Go, and Kotlin is dramatically better than either of them.

Re: Ask HN: Has anyone here programmed in Kotlin? What do you think about it?

#113

Post by mike_hearn »

throwaway999777 wrote: post #76
hhariri wrote: post #20

Earlier quoted context omitted.

To summarize, we were looking for a language that could cut down our code base (IntelliJ platform and server side tools are written in Java), be concise but still expressive, toolable, as fast as Java, easy ramp-up time, and very important, interoperable with all the existing code base we had. Given the candidates at the time, it was decided to start Kotlin.

Was there a need to develop a Java IDE in Java to begin with? I can understand dog fooding by building IDE-primarily-for-lang in lang itself. But were there technical reasons? Or maybe Java just was the best alternative [at the time].

It's worked out pretty well for them I'd say. Consider that any developer can write a plugin for it easily, that cannot segfault the entire app, and which runs on all the platforms the IDE supports. That's just one advantage. Higher productivity of feature development is probably another.

To see how things could have been different, look at Visual Studio which is still a 32 bit program even in 2015. Users of it complain that it simply can't load big projects without running out of RAM even if their computer has enough. The VS team says they aren't doing a 64 bit port because it's such a big code base and besides, their plugin model is fully native. And of course it's Windows only.

Re: Ask HN: Has anyone here programmed in Kotlin? What do you think about it?

#114

Post by throwaway999777 »

mike_hearn wrote: post #113
throwaway999777 wrote: post #76

Earlier quoted context omitted.

Was there a need to develop a Java IDE in Java to begin with? I can understand dog fooding by building IDE-primarily-for-lang in lang itself. But were there technical reasons? Or maybe Java just was the best alternative [at the time].

It's worked out pretty well for them I'd say. Consider that any developer can write a plugin for it easily, that cannot segfault the entire app, and which runs on all the platforms the IDE supports. That's just one advantage. Higher productivity of feature development is probably another. To see how things could have been different, look at Visual Studio which is still a 32 bit program even in 2015. Users of it compl…

> Higher productivity of feature development is probably another.

So productive that they had to invent a new language for the JVM platform?

Re: Ask HN: Has anyone here programmed in Kotlin? What do you think about it?

#115

Post by ninjakeyboard »

virtualwhys wrote: post #108
rattray wrote: post #103

Earlier quoted context omitted.

As someone who doesn't follow such things (eg; I don't recognize the "pron" or "adriaanm" usernames, and haven't used Scala or any other JVM language), I found your comment to be a turn-off towards using Scala. That's not the kind of mature tone I'd look for from the tech lead of an open-source language. That said, it is good to know that "pron" was incorrect/exaggerating when they said Scala adopts a lot of PL conce…

FYI, pron's the author of a would be competing project to Scala's Akka (i.e. competing for share of distributed computing market on the JVM), and takes every opportunity to danger-danger-dragons-be-there on Scala related threads/comments. Saying that, there is always some truth in what pron brings to the table, it's sort of a higher kinded trolling ;-) As for Scala and PL concepts, sure, plenty on offer if that's of…

What is a pron? That's like a shrimp?

Re: Ask HN: Has anyone here programmed in Kotlin? What do you think about it?

#116

Post by bkase »

warmfuzzykitten wrote: post #107
bkase wrote: post #31

We built Roll for Android ( http://tryroll.com ) in Kotlin -- we currently have ~17k lines and have been working on it since this Spring. We wanted to iterate on a lot of the software structure we came up with for our Swift iOS app, and for a bunch of pieces we needed a powerful type system. So rather than just stick with Java -- as others have said, it's way too verbose, we started looking at alternatives. We wanted…

Your comment on build speed is interesting. Do you have a ballpark figure for Kotlin compile speed in lines per minute?

Unfortunately, not. We had a bad gradle config for a while so when we fixed that our build time jumped down from 6min incremental to 2min. However, I can tell you that I haven't noticed an increase in build time since we fixed our gradle settings which happened a few months ago and we have added code. Maybe it's a function of gradle modules (we have around 25)? If we ever spend a bunch more time trying to optimize our build time we'll write about it somewhere.

Re: Ask HN: Has anyone here programmed in Kotlin? What do you think about it?

#117

Post by mike_hearn »

virtualwhys wrote: post #72

Well, let's look at the JVM landscape. First of all Oracle has (finally) picked up the pace in terms of evolving Java and the JVM. This is a bit of a double edged sword for alternative JVM languages since on the one hand JVM improvements (like current SAMs and value types in Java 10) are a big win for all involved, but on the other, Java's evolution is very much a threat to Scala, Kotlin, and Ceylon in particular* Wh…

I doubt it. Java 10 is very, very unlikely to match even a fraction of the features Kotlin has. Oracle is very obviously continuing Sun's strategy of focusing on the JVM rather than the Java language.

Their roadmap is pretty clear for the coming years, and it's all things like value types, better arrays, better APIs, modularity, performance, better ways to do "unsafe" stuff, etc. The only major change to the Java language they seem to be exploring right now is improved generics/class specialisation, and only because that's needed for the value types project.

Kotlin has basic things like real properties, which Java still lacks after two decades. Along with many other features.

The big competitors for Kotlin are Scala and Ceylon.

Re: Ask HN: Has anyone here programmed in Kotlin? What do you think about it?

#118

Post by mike_hearn »

mcintyre1994 wrote: post #109
virtualwhys wrote: post #72

Well, let's look at the JVM landscape. First of all Oracle has (finally) picked up the pace in terms of evolving Java and the JVM. This is a bit of a double edged sword for alternative JVM languages since on the one hand JVM improvements (like current SAMs and value types in Java 10) are a big win for all involved, but on the other, Java's evolution is very much a threat to Scala, Kotlin, and Ceylon in particular* Wh…

In clr land we've already seen c# adopting a fair few functional things - I think largely ahead of Java. There's this pretty interesting article from an f# (if anyone's unaware that's a Microsoft built functional language on the clr) tutorial site addressing reasons to still use f# over it. It's quite opinionated but worth a read and largely applies to Java/functional on the jvm: http://fsharpforfunandprofit.com/post…

There is a Haskell implementation for the JVM if you want a language like F# (it's called Frege).

Kotlin has some FP features. You can easily make immutable data classes (one line definitions of struct like things), you have map/filter/reduce/etc with a much more efficient approach than Java 8's streams framework, the compiler knows about tail recursion, there's some basic forms of pattern matching.

I suspect Kotlin will take a breather from new features for a while now to try and stabilise what they've got. But after that, I imagine a few more FP features might materialise.

Re: Ask HN: Has anyone here programmed in Kotlin? What do you think about it?

#119

Post by mike_hearn »

pjmlp wrote: post #11

Apparently Google used it for prototyping the new data bindings library in Android. https://www.reddit.com/r/androiddev/comments/3egzq5/so_has_g... For me the language looks nice as alternative to Java 6 on Android (or 7 when targeting 4.4 onwards), but those break@label, continue@label, .... put me off.

I'm surprised how often this comes up. What's the big deal with this syntax? It's not even used all that often, only in some special circumstances.

Re: Ask HN: Has anyone here programmed in Kotlin? What do you think about it?

#120

Post by mike_hearn »

warmfuzzykitten wrote: post #107
bkase wrote: post #31

We built Roll for Android ( http://tryroll.com ) in Kotlin -- we currently have ~17k lines and have been working on it since this Spring. We wanted to iterate on a lot of the software structure we came up with for our Swift iOS app, and for a bunch of pieces we needed a powerful type system. So rather than just stick with Java -- as others have said, it's way too verbose, we started looking at alternatives. We wanted…

Your comment on build speed is interesting. Do you have a ballpark figure for Kotlin compile speed in lines per minute?

Kotlin is not actually slow to compile. The problem is that incremental compilation and gradle/android don't mix. So it ends up recompiling the whole thing each time.

I use Kotlin for non-Android projects with Maven, so incremental compilation works. Build times are not a significant issue, though the Kotlin compiler is still not as fast as the Java compiler is. I noticed from doing hotswaps when debugging processes that Kotlin seems to still compile too much, even when in incremental model. So I hope once JetBrains get stability under control they can spend some time optimising.

Post reply on HN