Well, I prefer to think of cons-as-lists as one implementation of lists. It's possible to define alternative implementations of lists; all that is necessary is to define the overloads for 'car, 'cdr, 'scanner, and 'unscan. With generic functions in Arc-F, that is enough to iterate, cut, search, filter, join, map, and more on any list, regardless of whether it's made of 'cons cells or 'lazy-scanner objects.
