March Discussion

[alterationx10]

Starting a new discussion thread for March! What's on everyone's minds for Scala 3?

[8bitreid]

I would love to talk about given's and using's.

[alterationx10]

What's on your mind about using/givens? General usage, or something more meta programming related?

[8bitreid]

Have you seen https://youtu.be/sqTtZ3BQnRQ ? Lots of using and given. Blew my mind a bit. Doesn't have to be that crazy, but maybe we could talk about replacing json codecs that use implicit with given and using?

[alterationx10]

💯 I just watched it yesterday - pretty neat! given/using is the evolution of implicit.

So instead of something like this in Scala 2

implicit val myJsonCode[MyRecord]: JsonCodec[MyRecord] = ???
def encode(record: MyRecord)(implicit codec: JsonCodec[MyRecord]) = ???

If would become this in Scala 3

given JsonCodec[MyRecord] = ???
def encode(record: MyRecord)(using codec: JsonCodec[MyRecord]) = ???

given is used at the definition of an implicit, and using is at a call site of the implicit.

You can get away without naming them in some cases at both the definition and call site, since there should only be one in scope.

RockTheJVM has a nice articles about it here and here

[8bitreid]

so there is an explicit call to the given with a using?

[alterationx10]

You might say there's an implicit call to it 🤣 It doesn't have to be right next to it, just somewhere in the code base that's in scope where the using is called. The using is going to look through the implicit scopes to find the thing in scope

[alterationx10]

As we're a couple months in, I think it's a good spot to take a reflective look in and see where we can continue forward in a focused manner to make the most impact.

I think putting static site generators on the back burner is prudent. There are already a lot of tools set up to deploy sites, even if they aren't Scala based 🤣 With that in mind, the main Scala Works site will probably be ported over to something else soon.

At that point, I think the most impactful things will be

1. Making a high quality Scala Works site
2. Slim frameworks to help get started in the eco system
3. Micro libraries that you can take with you when you "graduate" away from the slim frameworks.