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

B Mo
B Mo
1,703 Points
Posted by B Mo
B Mo
1,703 Points

a little guidance for these quizzes would be helpful. how do i declare a variable of type id and set the value to nil?

i usually get the 1st question of the quizzes easily and have trouble with the 3rd question but this one i'm not getting the 1st question.

1 Answer

Nick Sint
Nick Sint
4,208 Points
Nick Sint
Nick Sint
4,208 Points

Okay lets break the questions down

  1. The task is to declare an "id" variable called thing. Note that unlike other types, "id" does not require a pointer. Usually you declare a string using "NSString *string = ..." but for id you just type "id variableName = ...". Therefore the correct statement to use here is:
id thing = nil;
  1. The NSNumber literal syntax is simply @number (i.e. @4 or @7 or @100). Therefore to assign thing to an NSNumber of 4,
thing = @4;
  1. Just remember here that the syntax for outputting a id variable is %@. 
NSLog(@"thing = %@",thing);