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iOS Objective-C Basics (Retired) Advanced Objective-C Dynamic Typing

Salman Sherif
Salman Sherif
891 Points
Posted by Salman Sherif
Salman Sherif
891 Points

Can this be done like this ?

Assign an NSNumber literal with a value of '4' to the variable 'thing'.

My code :- id thing = nil; thing = [NSNumber initWithObject:@4];

2 Answers

Stone Preston
Stone Preston
42,016 Points
Stone Preston
Stone Preston
42,016 Points

looking at the NSNumber class reference, there is not an initWithObject method of the NSNumber class. you are asked to assign it using a literal, so just use a literal 

id thing = nil; 
thing = @4;

here is the documentation on objective c literals in case you need a refresher

the challenge asks you to use a literal, but in the case you did not want to use a literal you could use a method like initWithInt or numberWIthInt like so

NSNumber *number = [[NSNumber alloc] initWithInt:4];
NSNumber *number = [NSNumber numberWithInt:4];