Returns a new set with the elements of both this and the given set.
Required. Default implementation provided.
- Xcode 8.0+
- Swift Standard Library
A set of the same type as the current set.
A new set with the unique elements of this set and
In the following example, the
attendees set is made up of the elements of the
If the set already contains one or more elements that are also in
other, the existing members are kept.