Help on "Programming with Objective-C Exercise.

Question

I'm working through the "Programming with Objective-C exercise and in the chapter "Working with Objects," there is a question to use the factory method as follows:
Implement the XYZPerson class person factory method you declared in the previous chapter, to return a correctly allocated and initialized instance of the XYZPerson class, then use the method in main() instead of your nested allocand init.
Tip: Rather than using [[XYZPerson alloc] init] in the class factory method, instead try using [[self alloc] init].Using self in a class factory method means that you’re referring to the class itself.This means that you don’t have to override the person method in the XYZShoutingPerson implementation to create the correct instance. Test this by checking that: 
    XYZShoutingPerson *shoutingPerson = [XYZShoutingPerson person];creates the correct type of object. 
I'm not sure how to impliment the "person" method.
My code looks as follows:
-(void)person
     [[self alloc]init];
After this I get various error messages when I try to change the code.
What is the benefit of using this initiation versus the [[XYZPerson alloc]init]; ?
Thank you.

Answer 1

I tried that but i got an error message: "result expression unused".
+(void)person
     [[self alloc] init];
in my main.m file,
XYZShoutingPerson *shoutingPerson = [XYZShoutingPerson person];
also gives me an error message "innitializing 'XYZShoutingPerson * __strong' with an expression og incompadible type 'void'
this is the link to the page from which I found the exercise.
https://developer.apple.com/library/mac/documentation/cocoa/conceptual/Programmi ngWithObjectiveC/WorkingwithObjects/WorkingwithObjects.html#//apple_ref/doc/uid/ TP40011210-CH4-SW1