Hi!
The idea of the universal polynomial ring naturally extends to other rings like Laurent-polynomial rings. So, it would be nice if there were a more "generic" implementation, let's call it "universal ring", which makes any ring with a fixed number of generators, like a polynomial ring or a Laurent-polynomial ring, into a corresponding ring with an extendable number of generators. This universal ring can then replace the current implementation of universal polynomial rings. Of corse some methods would need to be implemented specifically for the universal ring of Laurent-polynomials but I think most of the methods could be implemented in a generic way for all universal rings.

I'm asking for this because I'd like to implement generic cyclotomic rings, which are used in GenericCharacterTables.jl, with a fixed number of generators and then make them into a "universal" version with this new universal ring.

I haven't had a very close look into the code yet but I think this shouldn't be too hard and I should be able to implement this universal ring. What do you think about this?