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Official Forum for Programming in Objective-C (the iPhone Programming Language) - Stephen Kochan
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Programming in Objective-C, 4th edition
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Chapter 11
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NSComparisonMethods
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Topic: NSComparisonMethods (Read 2602 times)
Bertus
Newbie
Posts: 20
'Audaces fortuna iuvat'
NSComparisonMethods
«
on:
April 30, 2014, 06:49:55 AM »
In the exercise where we had to implement
Code: (Objective-C)
-(BOOL)isEqual:(id) object
why does:
Code: (Objective-C)
[object numerator]
work well, while:
Code: (Objective-C)
object.numerator
throws an error in X-code?
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BrianLawson
Sr. Member
Posts: 262
Re: NSComparisonMethods
«
Reply #1 on:
April 30, 2014, 07:53:29 AM »
Code: (Objective-C)
[object numerator]
sends the numerator message to the object instance while
Code: (Objective-C)
object.numerator
is trying to access the ivar numerator from the class that object belongs to. Do you have a numerator property? Can you post more of your code along with the error message you are seeing?
Logged
kotyara
Newbie
Posts: 15
Re: NSComparisonMethods
«
Reply #2 on:
December 14, 2014, 11:08:20 AM »
I had the same problem. The thing is that you cannot use the dot operator with id variables (Chapter 9).
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