I've not paid attention to Kotlin in a while, but it seems like there's more progress at supporting Kotlin across more platforms (Kotlin native, web?, etc). I'm curious if people feel that the language features and design are at about parity, or if one is significantly stronger/weaker.
BTW, JetBrains recently sunsetted AppCode, so they are bleeding their Swift talent now. I suspect that doesn’t bode so well for Kotlin‘s Swift interop.
Nowadays it runs everywhere and supports a variety of deployment targets (relying on local runtime, packaging it together into a single somewhat compact binary, natively compiling the code (NativeAOT, it's good but has some limitations) or mixing and matching all of the above).
It is also one of the best high-level languages to write performance-oriented code with, especially so with .NET 7 which allows writing cross-platform SIMD code in a similar fashion to Rust's 'portable-simd' crate.
And while it's tangential, Xaml drives me absolutely bonkers. It's like the worst parts of iOS Storyboards and Android Framework XML layouts except there's no escape hatch for those looking to build a UI in pure code (Android Framework is a bit of an offender here too, but Jetpack Compose looks to remedy that).
UI frameworks on the other hand…I feel your pain.
This is interesting because all these magical functions (zip, map, Rx etc) have roots in LINQ which sprung from .Net world. I find it hard to believe that the battle tested CLR and C# doesn't have the equivalent functions.
No they don't. They're essentially unchanged from ML back in the 1970s. The part that was new in C# was the SQL-like syntax on top of them, and most subsequent languages haven't considered that worth adopting.
Kotlin has it's roots in JVM and the early language design choices clearly reflect that. Kotlin/Native will find it very hard to break free of it's JVM counterpart because it can't diverge too much from it to maintain compatibility.
Swift and Kotlin are in many ways similar, but I find Swift to be a bit nicer in almost every respect. Swift has more powerful generics, tuples, structs, powerful enums that are value types, `if let`/`guard let` statements that I'll take over `?.let {}` any day, etc. Kotlin is somewhat more expression oriented, which is nice; Swift is moving in that direction too, but slowly.
A native Kotlin (I have no idea how mature it is) might be a decent alternative to high-level Rust, but I'll take Swift if it's available. It's both more pleasant to work in and I assume more performant with better access to stack allocated value types.
That said I've only used Kotlin in the context of Android development. It might be nicer elsewhere.