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0 pointsbad_user9y ago0 comments

Kotlin is just a Java++, akin to what CoffeeScript is to JS, a Java with a different syntax.

Scala is not just a Java with a different syntax. Because of how traits work and because of how they were encoded in Java's class format, in older Scala versions even adding a method with a default implementation breaks binary compatibility, which is why the history of Scala has been so fraught with compatibility breakage.

Scala 2.12 takes advantage of Java 8's new default methods in interfaces, among others, for encoding Scala's features. We finally have a Scala version that isn't so fragile. And because of the limited resources of the core team, they can't maintain different backends.

Java 8 was released in 2014. I cheered for Google when they won Oracle's lawsuit, but when you're forking the ecosystem, you have a responsibility to keep on your promise of keeping up to date and compatible with the upstream. They just pulled a Microsoft and are getting away with it.

Fuck Google for fracturing the Java ecosystem. There, I said it.

0 comments

cel1ne9y ago

Kotlin is not CoffeeScript for Java.

Kotlin is Java done much better. Null as syntax, extensions with receivers, reified typing, type-safe builders, first-class lambdas, sealed classes, co-routines and so much more...

Kotlin is my language of choice for just about everything at the moment.

I have done 15+ years of programming in Java (Desktop, Server, Android), JavaScript (ES5, ES6+), Kotlin and a little programming in Coffee-script. Your comparison is just wrong.

It's 100% compatible to Java so of course it's not a completely different language. Haskell is a different language. I like Haskell, but I'm glad that I don't have to convert all my old java code to it.

I can open old java-projects and use Kotlin on a file-by-file basis without any problems.

lmm9y ago

If Kotlin wasn't just CoffeScript for Java but a whole new language then there would be no reason to use it instead of Scala. There's an excluded middle here: either it's a very-close-to-Java language (in which case probably not worth the cost of using) or it's a language that's significantly different from Java (in which case it has no interop/familiarity advantage over Scala and the two languages have to be compared on their merits - and I'd say Kotlin comes off pretty poorly in that).

> It's 100% compatible to Java so of course it's not a completely different language. Haskell is a different language. I like Haskell, but I'm glad that I don't have to convert all my old java code to it.

> I can open old java-projects and use Kotlin on a file-by-file basis without any problems.

Sure. I do exactly that in Scala too.

Larrikin9y ago

One of the arguments against Scala is that its large and simply too feature rich. https://agilewombat.com/2016/02/01/scala-vs-kotlin/

1 more reply

pkolaczk9y ago

Kotlin doesn't really have true reified generics (any more than e.g. Scala has), Java 8 has first class lambdas, extension methods and @Nullable now. Kotlin is just Java 8 with cleaner syntax.

ptx9y ago

I'm no expert on Java 8, but it looks like the new feature they call "extension methods" is just the ability to define methods in interfaces and inherit them, essentially like a concrete method in an abstract base class, isn't it?

The "extension methods" in Kotlin (and C#) is a completely different feature: syntactic sugar for static utility methods, which allow you to add new methods to any class without needing to modify the original class. (Or at least make it look that way syntactically.)

So in Kotlin you can do this:

  fun String.toLeetSpeak(): String {
     val charmap = mapOf('e' to '3', 'l' to '1')
     return this.map { charmap[it] ?: it }.joinToString(separator="")
  }

  fun main(args: Array<String>) {
      println("Hello!".toLeetSpeak())
  }

...whereas in Java you would have to change (and have access to) the implementation of one of the classes or interfaces that String inherits from.

2 more replies

dep_b9y ago

The @Nullable syntax is akin to putting a band-aid on a rotting leg. You cannot fix Java without breaking compatibility with older code. They only way to see it is not to look at the problem from the inside out when you have been surrounded with Java for perhaps decades in your career.

In my code null-pointer exceptions or similar accidents (force unwrapping something that simply doesn't exist) never happens anymore. Not in my libraries and not in my program code. A whole class of bugs just gone. Simply because I have to prove that something exists before I use it at compile time already.

It's like having security that starts with everything turned OFF for a default user instead of ON.

cel1ne9y ago

Kotlin has generics that are in most circumstances reified enough ;).

Optionals of Java8 and Guava are a terrible idea. @Nullable is just an annotation. Null-safety built in the language is the only way to go.

You could always argue that a language is just cleaner syntax. Kotlin is a cleaner syntax for interacting with JVM-bytecode. Scala is a also cleaner syntax for interacting with JVM-bytecode. JVM-Bytecode is a cleaner syntax for interacting with operating systems.

2 more replies

pjmlp9y ago

> Fuck Google for fracturing the Java ecosystem. There, I said it.

Right on the spot, yet as Silicon Valley darling they get a free pass instead of being blamed like Microsoft was.

I still hope Oracle manages to force them to play by rules.

Other JVM vendors like IBM, Atego, Azul, MicroEJ,.... are able to provide their own extensions, while supporting Java properly and not forking the whole language + standard libraries.

Some of them do sell JVMs for embedded devices with soft and real-time constraints much higher than Android, so the whole story about a Java fork being a requirement for Android is such Google marketing for their actions.

dep_b9y ago

> Kotlin is just a Java++, akin to what CoffeeScript is to JS, a Java with a different syntax.

Kotlin is a smaller language than Java (just based on my feeling actually) yet more safe and in many regards flexible. Kotlin is more similar to Swift, where Swift is aimed at Cocoa and Kotlin at the JVM.

The only thing it really has in common is that it uses the JVM. But F# is not similar to C# just because it has .Net compatibility. Especially if you try to write C# in F# instead of F# according to the gospel.

Just as I've seen tons of code by Objective-C devs that's just the old code translated to the new code a lot of Java devs probably won't really get Kotlin and will write the same code as they would do in Java.

j / k navigate · click thread line to collapse

0 comments

cel1ne9y ago

Kotlin is not CoffeeScript for Java.

Kotlin is Java done much better. Null as syntax, extensions with receivers, reified typing, type-safe builders, first-class lambdas, sealed classes, co-routines and so much more...

Kotlin is my language of choice for just about everything at the moment.

I have done 15+ years of programming in Java (Desktop, Server, Android), JavaScript (ES5, ES6+), Kotlin and a little programming in Coffee-script. Your comparison is just wrong.

I can open old java-projects and use Kotlin on a file-by-file basis without any problems.

lmm9y ago

> I can open old java-projects and use Kotlin on a file-by-file basis without any problems.

Sure. I do exactly that in Scala too.

Larrikin9y ago

One of the arguments against Scala is that its large and simply too feature rich. https://agilewombat.com/2016/02/01/scala-vs-kotlin/

1 more reply

pkolaczk9y ago

Kotlin doesn't really have true reified generics (any more than e.g. Scala has), Java 8 has first class lambdas, extension methods and @Nullable now. Kotlin is just Java 8 with cleaner syntax.

ptx9y ago

So in Kotlin you can do this:

  fun String.toLeetSpeak(): String {
     val charmap = mapOf('e' to '3', 'l' to '1')
     return this.map { charmap[it] ?: it }.joinToString(separator="")
  }

  fun main(args: Array<String>) {
      println("Hello!".toLeetSpeak())
  }

...whereas in Java you would have to change (and have access to) the implementation of one of the classes or interfaces that String inherits from.

2 more replies

dep_b9y ago

It's like having security that starts with everything turned OFF for a default user instead of ON.

cel1ne9y ago

Kotlin has generics that are in most circumstances reified enough ;).

Optionals of Java8 and Guava are a terrible idea. @Nullable is just an annotation. Null-safety built in the language is the only way to go.

2 more replies

pjmlp9y ago

> Fuck Google for fracturing the Java ecosystem. There, I said it.

Right on the spot, yet as Silicon Valley darling they get a free pass instead of being blamed like Microsoft was.

I still hope Oracle manages to force them to play by rules.

Other JVM vendors like IBM, Atego, Azul, MicroEJ,.... are able to provide their own extensions, while supporting Java properly and not forking the whole language + standard libraries.

dep_b9y ago

> Kotlin is just a Java++, akin to what CoffeeScript is to JS, a Java with a different syntax.

j / k navigate · click thread line to collapse