Chimney VS dotty

But yeah, I wonder if using a tool for case classes conversion like https://github.com/scalalandio/chimney would help in managing those ADT hierarchies for DB/business logic/web layer/etc.

Hello, if you have some nice examples could you please check if it's something that would fit any of issues planned for 0.7.1 or create a new one?

Perhaps, https://github.com/scalalandio/chimney would leverage it.

Thankfully, there are some solutions that can help reduce the boilerplate of these manual conversions. For instance, chimney : https://scalalandio.github.io/chimney/

I want to upgrade one project to Scala 3.1, but I'm using the macro heavy chimney (https://github.com/scalalandio/chimney) to reduce the boilerplate, which is not available for Scala 3 yet. My idea was to copy and paste the code that chimney generates on 2.13, and after that uncomment the uses of chimney for now.

In my $dayjob we originally used Scala, but I pushed for a couple of new services to be written in TypeScript/Node as it was really hard to hire Scala developers. I'd say it worked well, we even took a somewhat functional approach to building things. We tried fp-ts but that was a bit hardcore (when you are trying to hire TypeScript developers who don't know functional programming), so just built Either and Option types which provided 99% of what we needed.

There are still a few things I miss though:

* Pattern matching and exhaustive checking. Using a switch statement it is possible to define a function that can emulate the compile-time exhaustive checking, but it's still rather weak compared to what you can do in Scala.

* Implicits. Being able to define something that can convert say a UUID to a String or vice versa automatically just feels like magic, especially when dealing with data from third party systems.

* Compiler macros and metaprogramming. It enables tools like Chimney (https://scalalandio.github.io/chimney/) to be built, which I don't think are possible with TypeScript right now.

Converting between these classes can add some boilerplate, but luckily there are libraries like https://github.com/scalalandio/chimney that make it much easier.

Dotty? Was it still the name later?

http://dotty.epfl.ch/

I think this might be related to this issue.

You can look (and EPFL collect feedback) about EPFL implementation of async/await: https://github.com/lampepfl/async. Also you can look at dotty ticket about this: https://github.com/lampepfl/dotty/pull/16739

The reason I’m not currently an opaque type user as they do not play well with the tagless final style we use, though I am patiently awaiting some attention on my bug report: https://github.com/lampepfl/dotty/issues/17281

Links: - https://dotty.epfl.ch/ - https://scala-native.org/en/stable/ - https://www.scala-js.org/ - https://typelevel.org/ - https://zio.dev/ - https://github.com/scala-native/scala-native/pull/3120 - https://github.com/lampepfl/dotty/pull/16517 - https://dotty.epfl.ch/docs/reference/experimental/index.html - https://scala-cli.virtuslab.org/ - https://scalameta.org/metals/ - https://docs.scala-lang.org/scala3/guides/migration/compatibility-intro.html - https://www.scala-lang.org/blog/2023/04/18/faster-scalajs-development-with-frontend-tooling.html - https://www.scala-lang.org/blog/2022/08/17/long-term-compatibility-plans.html

Scala Native has much more control on how the Scala AST is compiled, and can easier workaround platform limitations, eg. lazy vals in Scala 3 required reflection config for Native Image (see this and that), while in Scala Native we could mitigate problems with unsupported usage inside in other ways within the compiler plugin.

By the way, you might be interested in this recent PR which overhauls the scala 3 macro docs: https://github.com/lampepfl/dotty/pull/17060.

For example, this issue (https://github.com/lampepfl/dotty/issues/12840) was blocking the migration, it was reported more than a year ago and the fix was finally released a month ago (https://github.com/lampepfl/dotty/releases/tag/3.3.0-RC2).

For the record, there is an implementation of :javap which is close to being done but might need a volunteer to get it over the finish line: https://github.com/lampepfl/dotty/pull/12210

im glad to tell you that in 3.3.0 a lot of these -Wunused lints will be supported: see https://github.com/lampepfl/dotty/pull/16157