Experiment with -Xasync

[djspiewak]

According to @retronym it works with Cats Effect. Let's like… actually do it. I would very much like it if users could opt-in to this syntax for interacting with at least IO, and ideally any effect type.

[Baccata]

I've got something working. IOs are executed sequentially, and I haven't figured out why yet :

• implementation
• example call

[renghen]

https://github.com/rssh/cps-async-connect

Have same goal as async await, hope you can take some ideas

[Baccata]

@renghen thanks for sharing, that's pretty cool !

Unfortunately in scala-2 land the integration point is much less straightforward (if you want to tap into the mechanism enabled by the -XAsync flag and not write complex AST transformations from scratch, that is). I really hope that if the flag gets ported to scala-3, the underlying mechanism will be similar to the one you offer in dotty-cps-async, and that if the flag wasn't ported for whatever reason, your library would be used as a point of reference to obtain feature parity.

On an unrelated note, I was thinking that at some point I'd try implementing arrow-comprehensions (similar to https://github.com/manatki/volga) in Scala 3, and you work seem like it'd be a good starting point (the macro examples on dotty's website lack depth)

Thanks again for sharing 😄

[renghen]

one note this is not my work (https://github.com/rssh/cps-async-connect) I am just interested in Continuation passing style.
So I follow that repo and hope for something like suspend like in kotlin will get into scala.

I will also look into the git repo you mentioned.

cheers

[Baccata]

Hah my bad. Still, thanks for sharing 😄

[b-studios]

I just want to mention that similar things can be achieved building on monadic reflection and project loom: https://github.com/b-studios/cats-reflect

• The advantage is that you do not need a translation and it "just" works. In particular with higher-order functions like map.
• The disadvantage is that you need a Loom runtime -- it is much easier now since pre-release binaries are available, but it is still not the standard.

[djspiewak]

@b-studios That is really really cool

[b-studios]

Thanks @djspiewak! FYI, we moved our experiments here: https://github.com/lampepfl/monadic-reflection