Time complexity of Swift's Set.indexOf

Question

What is the time complexity of Set.indexOf? The documentation doesn't say, and the source delegates to some kind of internal storage class (_VariantStorage/_VariantSetStorage) whose source I can't find.

Answer 1

The documentation for CollectionType suggests that it is O(self.count).

That would make sense, as the worst case scenario is that every element in the Set (or any other collection) is checked for equality. It shouldn't ever be more complex than O(self.count).