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iOS

Posted by Pablo Kvitca
Pablo Kvitca
Courses Plus Student 9,624 Points

Advanced Objective-C Dynamic Typing Challenge

I'm trying to learn about Dynamic typing, actually I only have this challenge left butI'm stuck on Task 2. The task is: "Assign an NSNumber literal with a value of '4' to the variable 'thing'."

and my current input (from Task 1) looks like this: "id thing = nil;"

What should I do?

2 Answers

Aaron Kison
Aaron Kison
5,758 Points

All literals in objective-c are prefixed with the @ symbol. So a literal number 4 is represented using @4 Your code should look something like

id thing = nil;
thing = @4;

You could also use the helper construction method with NSNumber like:

id thing = nil;
thing = [NSNumber numberWithInt:4];
Pablo Kvitca
PLUS
Pablo Kvitca
Courses Plus Student 9,624 Points
Pablo Kvitca
Pablo Kvitca
Courses Plus Student 9,624 Points

Thank you!! I had tried "thing = 4". I had forgotten about the @. Thank You!!!!!