That sounds like a subclass of Bag to me. But I don't think that thinking about who is subclassing whom is is how to think about this in Perl 6. All of these types are capable of doing the Iterable role, and that is what methods that could operate on a List, Array, Bag, or Set, should be calling for.
On Oct 25, 2010, at 08:08 PM, yary wrote: > +1 on this > On Mon, Oct 25, 2010 at 4:56 PM, Jon Lang <datawea...@gmail.com> wrote: >> As for the bit about sets vs. lists: personally, I'd prefer that there >> not be quite as much difference between them as there currently is. >> That is, I'd rather sets be usable wherever lists are called for, with >> the caveat that there's no guarantee about the order in which you'll >> get the set's members; only that you'll get each member exactly once. >> The current approach is of much more limited value in programming. > > I think of a list conceptually as a subclass of a set- a list is a > set, with indexing and ordering added. Implementation-wise I presume > they are quite different, since a set falls nicely into the keys of a > hash in therms of what you'd typically want to do with it.