[partisan]

I am not sure that Kotlin competes with Scala in any way. They are trying to remove the pain from Java by providing a concise and safe language (see the quotes from their website below). What are "all the things" they reinvented that were discard in Scala?

> Kotlin is a pragmatic programming language for JVM and Android that combines OO and functional features and is focused on interoperability, safety, clarity and tooling support.

> Being a general-purpose language, Kotlin works everywhere where Java works: server-side applications, mobile applications (Android), desktop applications.

[premium-concern]

> What are "all the things" they reinvented that were discard in Scala?

Extension methods, properties, special syntax for everything, final by default, short constructor syntax, trying to put band-aid around Java's broken collection types, ...

[didip]

I'd love to learn more about Java's broken collection types. What's broken about them?

[premium-concern]

The pattern of throwing exceptions for operations deemed "unsupported", an API that requires massive workarounds to keep alive in Java 10, no support for immutable collections, unmodifiable views are a complete clusterfuck, no persistent collections etc.

[partisan]

Thank you. I appreciate the list.

[ionforce]

Kotlin competes with Scala in that they are both alternatives to Java.

[yawaramin]

Every single description of Kotlin in your comment could just as easily be describing Scala.