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

Posted by Sergey Geraskov
Sergey Geraskov
3,621 Points

don't understand where is a mistake...

In challenge task I have to assign an NSNumber literal with a value of '4' to the variable 'thing'.

I have done:

  1. id thing=nil;
  2. NSNumber *thing= at4;

Where is a mistake... Please help me ...

PS. "at" cann't write in symbol here.

2 Answers

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

your object is of type id, so you can just assign it an NSNumber literal like so:

id thing = nil;
thing = @4;
Sergey Geraskov
Sergey Geraskov
3,621 Points
Sergey Geraskov
Sergey Geraskov
3,621 Points

thanks for answer)

that was a noob question...

Stone Preston
Stone Preston
42,016 Points

not at all. the dynamic typing can be a little confusing, which is why its one of the last topics covered