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

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?

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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.


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