Any good examples of `FirTypeAttributeExtension`? I'm trying to implement Scala's <Capture Checking...

# compiler

[Youssef Shoaib [MOD]]

Any good examples of FirTypeAttributeExtension?

I'm trying to implement Scala's Capture Checking as a FIR plugin. FirTypeAttributeExtension doesn't seem enough on its own though, and likely I have to add some checkers as well, no? Does FirTypeAttributeExtension affect call resolution as well? I don't actually want that, so I'm hoping it doesn't.

[Youssef Shoaib [MOD]]

In fact it seems like what I'm asking for is some explanation of ConeAttribute and how to use it! Seems like it has isSubtypeOf, which is likely what I want!

[bnorm]

The sandbox plugin has an example of @Positive and @Negative annotations which are translated to an attribute which can then restrict function calls. There's a test which shows some examples as well.

[Youssef Shoaib [MOD]]

Given how underused as an extension it is, is it likely to go away? I know there's 0 guarantees about FIR extensions in general. I guess more so, are there any plans to get rid of it? Is it a maintenance burden? Or is it simple enough that like there's no reason to get rid of it short-term?
I know that's a difficult question to answer, so feel free not to! I'm just trying to figure out if I should build something purely using Checkers instead (since Checkers seem unlikely to go away in one form or another).

[bnorm]

I think it's unlikely to go anywhere. ConeAttributes have significant use internally and this extension is a very low maintenance burden.