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Learn Kotlin in Y Minutes

learnxinyminutes.com

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Re: Learn Kotlin in Y Minutes

#11

Post by shallot_router »

notamy wrote: post #10

Honestly I could never really get into Kotlin. I like the features of the language - and would love to have many of them in plain ol' Java - but the syntax just feels wrong to me and I've not been able to get over it.

I find it a huge improvement over Java, but I wish it would have more syntax sugar for lists/arrays/maps like Swift and dynamic languages do.

The mix of "hip" programming language constructs with unchanged Java verbosity feels weird to me. But if I were making an Android app, I'd definitely try to do it with Kotlin first.

Re: Learn Kotlin in Y Minutes

#12

Post by WaxProlix »

shallot_router wrote: post #11
notamy wrote: post #10

Honestly I could never really get into Kotlin. I like the features of the language - and would love to have many of them in plain ol' Java - but the syntax just feels wrong to me and I've not been able to get over it.

I find it a huge improvement over Java, but I wish it would have more syntax sugar for lists/arrays/maps like Swift and dynamic languages do. The mix of "hip" programming language constructs with unchanged Java verbosity feels weird to me. But if I were making an Android app, I'd definitely try to do it with Kotlin first.

What kind of sugar are you looking for? I'd like to have first-class comprehensions in any language I use, but having decent map/filter/reduce|fold implementations is good enough for the most part.

(1..100).map({ it + 10 })

Doesn't seem so bad.

Re: Learn Kotlin in Y Minutes

#18

Post by betatest »

shubb wrote: post #9

In terms of why we'd want to, there is this note here: https://kotlinlang.org/docs/reference/comparison-to-java.htm... Other factors to consider are tools support, how often interoprability with java libraries causes problems. Would be nice to hear from someone who has used it a bit about what the state of these is?

Come on. This is not about actual production stuff. It's new! It's cool! That's pretty much it.

Re: Learn Kotlin in Y Minutes

#19

Post by dcow »

WaxProlix wrote: post #12
shallot_router wrote: post #11

Earlier quoted context omitted.

I find it a huge improvement over Java, but I wish it would have more syntax sugar for lists/arrays/maps like Swift and dynamic languages do. The mix of "hip" programming language constructs with unchanged Java verbosity feels weird to me. But if I were making an Android app, I'd definitely try to do it with Kotlin first.

What kind of sugar are you looking for? I'd like to have first-class comprehensions in any language I use, but having decent map/filter/reduce|fold implementations is good enough for the most part. (1..100).map({ it + 10 }) Doesn't seem so bad.

You can even get rid of the final parentheses.

(1..100).map { it + 10 }

Re: Learn Kotlin in Y Minutes

#20

Post by on_and_off »

shubb wrote: post #9

In terms of why we'd want to, there is this note here: https://kotlinlang.org/docs/reference/comparison-to-java.htm... Other factors to consider are tools support, how often interoprability with java libraries causes problems. Would be nice to hear from someone who has used it a bit about what the state of these is?

I can talk about this in the context of Android.

First I should point out that many large Android apps are using Kotlin. There is a lot of momentum behind Kotlin on Android, that's why Google adopted it.

Tools support is really good. Jetbrains knows how to create tools and it shows. Using kotlin also shows you how great the android plugin for java is. Nothing major, but little features like shortcuts to create a string/drawable resource are sometimes missing in kotlin. Jetbrains is missing that gap though, and we should quickly reach parity now that the language is officially supported.

Interop with Java is equally great ! Both java & kotlin output bytecode, so they can dialog easily.

Some interop caveats : - sometimes calling java from kotlin is not idiomatic. However nowadays many libs are already offering kotlin bindings and again, this should improve.

- similarly, calling kotlin from java can be a bit awkward syntactically speaking.

- kotlin guarantees nullability behavior, but this can be broken at the interface with java in a couple of cases. If the java code lack @nonnull @nullable annotations, it is up to you to handle their nullability. Similarly, kotlin classes instantiated from java code can mess with nullability. If you data class contains a nonnull property and you instantiate this class with Moshi (a json parser), if the corresponding json field is missing you end up with a null field on a nonnull property.

So it is pretty rare, but you can still end up with some NPE.

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