For collections — which are value types —that contain reference-typed instances, when they are copied, do the elements get copied over as well? My guess is no, since that feels confusing given that the elements are reference types.
Do collection types perform shallow copies?
Yes, they perform shallow copies. This follows directly from reference semantics. There is no general way to deep copy an arbitrary reference type.
This generalizes to any value type containing references (e.g. structs).
Thank you. Is it worth it to ask the Swift group to discuss more about mixing reference types and value types? I read through the struct vs classes doc and it didn’t discuss this edge case which can also help to clarify what a complex value type even is.