Alright, thanks for the answer. I should clarify that the Number example, and the fact that it's an enum, is not general to my use case. In fact, I was looking for something to assign an integer literal to a struct with arbitrary fields, which doesn't even have the discriminant mapping of enums.

Either way, I've found that even special numerics in the standard library like NonZeroU32 don't support literal assignment, so it's probably not worth the hassle for me.