Trait object with associated types in field - requires generic param?

Дата публикации: 07-10-2026 16:02:43

I currently have:
trait ListModel {
fn get_stuff(&self, row: i) -> Stuff;
...
}
struct List {
model: Rc<dyn ListModel>,
...
}
I think I want to change my model to use row IDs instead of usize indices. If I do this:
trait ListModel {
type Key: Eq + Hash + Clone;
fn get_stuff(&self, row: Key) -> Stuff;
}
There is no way to keep List non-generic, correct? I need to have something like these? :
struct List<M: ListModel> {
model: Rc<M>,
}
// or
struct List<K> {
model: Rc<dyn ListModel<Key = K>>,
...
}
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