What are isKindOfClass and isMemberOfClass for?

Junior PRO

Essence

Both are runtime introspection of an object's type (from the NSObject protocol):

isKindOfClass: — YES if the object is an instance of the class or any of its subclasses. Walks the superclass chain.
isMemberOfClass: — YES only if object_getClass(obj) equals exactly this class. Subclasses do not count.

For protocols the analogue is conformsToProtocol:, for methods — respondsToSelector:.

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