Anonymous union variants

[domn1995]

Some times we want to make a very basic union without naming its variants. We should be able to do something like:

public partial record struct Number : Union<int, double>;

This would enable us to do the following:

var integer = new Number.Int();
var @double = new Number.Double();

Should it support generics? Should it require you to name its variants or infer from the type name?