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iOS Solution: Tower Defense Game

Ryan Carlson
Ryan Carlson
3,529 Points
Posted by Ryan Carlson
Ryan Carlson
3,529 Points

Hi. I was wondering why the sqrt() doesn't work when it's above the "import Foundation"?

The math works out, but I get an error. I'm pretty sure it has something to do with the "import Foundation", I just wanna know what that is. Thanks!

1 Answer

Thomas Dobson
Thomas Dobson
7,511 Points
Thomas Dobson
Thomas Dobson
7,511 Points

Any import statements should be above any code that references it. You should generally do your imports at the very top of your file. For example:

//Top of file
import Foundation

//Lots of code
//More code
//You get the idea

sqrt(4)

Generally speaking code is executed top to bottom. If a function or class is called before the referenced material is made available (i.e. Import Foundation) then your call will fail. 

sqrt(4) //Because this is executed before its imported, the compiler does not understand how to process it.
import Foundation

I hope this helps!

Ryan Carlson
Ryan Carlson
3,529 Points
Ryan Carlson
Ryan Carlson
3,529 Points

Thanks Thomas! Makes total sense!!