Makes sense, hope they make it soon to the compiler

A little bit of an update, I talked about the actual extensions, they are going to remove the type intercepting one, replacing with special annotation instance which can participate in type checking (checking annotation equality + usual types). call interception still going to be there.

that's very interesting indeed

If that is union/sum without the need to create sealed hierarchies then we are also working on that in Meta

Do you have any draft on that? I guess it is not coming anytime soon from design side. Also I was talking with the annotation processing team, they are planning to make apt-like compiler plugin, but that will go through proper Keep process.