This is not solved by the relational model? I have think about this for my toy relational lang, I consider too the best is allow: fun print(people:People[

This is not solved by the relational model? I have think about this for my toy relational lang, I consider too the best is allow: fun print(people:People[id, name])... to work with any relation/class/struct that at least have that 2 fields. Also, in the relational model the name of the relation and the header is significant. Plus, re-combining of types is inbuilt. Need to extent person? rel Customer Person join Address, Phones...