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Dynamic Typing Code Challenge Unsolved :-(

Can anyone help me with this code challenge? https://teamtreehouse.com/library/dynamic-typing

It goes like this: "Declare a variable named "thing" of type 'id' and initialize it to 'nil'." This works in Xcode:objective-c id thing = @[@"nil"]; This works in Xcode:objective-c id thing = @"nil"; but when I submit it to the Code Challenge, it says:"Bummer! Did you declare the variable 'thing' and set it to 'nil'?"

What am I doing wrong and how should I solve this challenge?

3 Answers

Holger Liesegang
Holger Liesegang
50,595 Points

Hi Matej, try using id without @ as it is already implicit.

Hi Matej, When you set it up as id thing = @"nil"; you actually defined |thing| as a string object with the value "nil" (i.e. the string, "nil") and not the actual nil value :)

id thing = @"nil" works on x-code because |id| can be passed any type of object; therefore, it is syntactically correct and will compile.

Thanks a lot! This worked: id thing = nil; btw, what does that @ stand for? what does it say? yup, I'm a beginner :-)

When someone answers your question and helps you resolve the problem, please choose a "Best Answer". This way, the person who gave you the answer gets extra points and it encourages participation.

Oh, and welcome to Treehouse. ;)

Holger Liesegang
Holger Liesegang
50,595 Points

Hi Jessica, congrats for your new status as a moderator :-)

Thanks. ^_^;;