One of the things about Objective-C that I find extremely useful is the ability to resolve a method call at runtime. In addition this same functionality allows us to do some fairly creative things with callbacks, passing messages between threads, etc.

However there is a bit of a trick when it comes to passing primitives though some of these methods. For example, one method that I use quite frequently is performSelectorOnMainThread:withObject:waitUntilDone:. How exactly does one pass a BOOL or an int to this method?
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