Use of std.sumtype.SumType instead of std.variant.Algebraic

[tom-tan]

Currently Node type internally uses std.variant.Algebraic but the official document says it becomes outdated.

Is there a plan to migrate from Algebraic to std.sumtype.SumType or can I send a pull request for it?
IMO it is worth doing because it enables D-YAML to work with attributes such as pure.

[Herringway]

It is something I wanna do eventually, but at the moment it doesn't really add a lot of value by itself. There are a few other dependencies that block pure, like std.regex, and that doesn't appear to be changing anytime soon...