class extension in objective-c

Question

I am learning object-c by reading a book. When I read the chapter about class extension, the book gives the following example code:

// A class extension
@int         


        

Answer 1

It is a little bit misleading to say "objects can no longer see". Objects doesn't see anything, even in the figurative sense. Let`s say: Code placed outside the implementation of the class cannot see the property.