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

Jay Caston
Jay Caston
3,941 Points

How to declare a variable as type id and initialize it to a string.

I'm on the challenge regarding dynamic typing and the first step of the challenge is to declare and initialize a variable of type id. This seems like it could be easy enough, but the nature of the dynamic type id is that it could be initialized to any type of value. The video didn't cover how to initialize a variable of type id, so every time I try to initialize it as I would another variable type I get an error.

How does one initialize a variable of type id?

Thanks

2 Answers

Holger Liesegang
Holger Liesegang
50,595 Points

Hi Jay,

I know that it's not explicitly told in the videos. You declare a variable named "thing" of type 'id' and initialize it to 'nil' like so:

id thing = nil;

...and notice that there is no asterisk in this declaration, as id implies the asterisk.

You also might find you don't call methods, you send messages interesting if you are into more details :)

Just some feedback, it's a little frustrating when the challenges don't refer back to what was just learned in the videos, or when the videos show a different way to do things than what the challenges ask for. Thanks for your answer, and great work overall, thanks!