Why do Objective-C objects have to be dynamically allocated?

Question

Why do Objective-c objects have to be dynamically allocated? Why do I have to make it a pointer to an object, unlike in C++ I can create them on stack? Thanks.

Answer 1

This is because of the way Objective-C uses dynamic or late binding. Unlike C++ where you'll always have the choice between calling a function of a class by it's object or via a pointer of the same class or even of a superclass. In the latter case polymorphism is required.

However, in Objective-C there exists always the ability to determine the correct function at runtime. The difference is, that for example in C++ the compiler has to ensure, that the used function exists, whereas in Objective-C the compiler doesn't really care, the runtime system decides only.