Small things that matter in #Scala 3: top-level methods. It’s surprising how often having a function outside the scope of any object/class just makes sense. No more artificial method containers! - ThreadSky

warski.org • 92 days ago

Small things that matter in #Scala 3: top-level methods.

It’s surprising how often having a function outside the scope of any object/class just makes sense. No more artificial method containers!

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alexn.org•92 days ago

We can finally escape the "kingdom of nouns" 💪

https://steve-yegge.blogspot.com/2006/03/execution-in-kingdom-of-nouns.html

michal.pawlik.dev•92 days ago

This can be a trap for library developers. Renaming a file makes you break the contract.

warski.org•92 days ago

True ... not so great, then ;)

michal.pawlik.dev•91 days ago

Top-level methods are present in many popular languages, so it made sense to introduce them for smoother newcomer experience. It makes sense as a concept. Implementation makes it problematic

jakubjanecek.bsky.social•92 days ago

How do you deal with the fact that the filename gets encoded into the FQN of the method? It's logical and not anything new but given how top-level definitions are presented I was very much surprised when I got conflicts because I had the same filename (e.g. package.scala) in main and test sources.

warski.org•92 days ago

I did not encounter this problem (yet), so I don't have any particular feelings :) Won't this cause problems with refactoring, though? If the same method starts to live in a different file (still top-level definition, same package). Such a change might not be binary-compatible then?

warski.org•92 days ago

That said, I try to use descriptive names for the files containing the top-level methods, so not `package.scala` but rather `files.scala` or whatever the purpose of the code there

jakubjanecek.bsky.social•92 days ago

I agree. However, in my opinion using descriptive names is very close to actually putting the definitions into named object (it's basically just one extra line like "object MyUtils:") so given the surprise with bincompat and filenames I rather do that to be explicit.

warski.org•92 days ago

Yeah this might have hidden traps, thanks for pointing this out. Still, using an object was always a hack, and in a way abused the notion of an object.

jakubjanecek.bsky.social•92 days ago

Exactly! Changing the filename is not binary compatible which in my view is very unexpected (though logical). It's actually described here: https://docs.scala-lang.org/scala3/reference/dropped-features/package-objects.html

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