Programming in Objective-C, Sixth Edition

They’re Not Objects!

Now you know how to define arrays, structures, character strings, and unions, and how to manipulate them in your program. Remember one fundamental thing: They’re not objects. Thus, you can’t send messages to them. You also can’t use them to take maximum advantage of nice things such as the memory-allocation strategy that the Foundation framework provides. That’s one of the reasons I encouraged you to skip this chapter and return to it later. In general, you’re better served learning how to use the Foundation’s classes that define arrays and strings as objects than using the ones built in to the language. Resort to using the types defined in this chapter only if you really need to—and hopefully you won’t!