Is there a difference between "is" and isKindOfClass()?

Question

Swift provides the is keyword (and as?) to check whether an object can be downcast successfully:

if foo is MyClass {     // ... } 

But NSObjectProtocol also provides the original func isKindOfClass(aClass: AnyClass!) -> Bool:

if something.isKindOfClass(MyClass) {     // ... } 

For classes conforming to NSObjectProtocol, is this really much different?

Answer 1

Yes there is a difference: is works with any class in Swift, whereas isKindOfClass() works only with those classes that are subclasses of NSObject or otherwise implement NSObjectProtocol.