[_a_a_a_]

With respect, and also with the understanding that I do not comprehend your domain very well so I may be talking out of my but with static typing I think it is possible, perhaps if a bit less pretty.

I can try and put something together in C# but not right now I'm afraid (it would be a good exercise for me as I've only read up on these, not actually use them personally, although I plan to start very soon for my own personal work). There was some examples going round here https://old.reddit.com/r/programming/comments/zm7f9/phantom_... which may help.

Again, I may be misunderstanding your domain completely, so bear it in mind please.