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iOS Error Handling in Swift 2.0 Error Handling Throwing Errors

Posted by Billy Potts
Billy Potts
Courses Plus Student 2,344 Points

Am i throwing this error wrong ??

For this task, let's get some practice throwing an error. You've been provided with an error object in the editor. Errors are typically thrown from inside functions so let's start by creating a function that can throw. Name this function lend. It takes no parameters and has no return type.

error.swift 
enum BookError: ErrorType {
  case IncorrectTitle
}

func lend () throws -> {
  throw BookError.IncorrectTitle 
}

3 Answers

jcorum
jcorum
71,830 Points

Your work is great except for one small problem:

func lend () throws {
  throw BookError.IncorrectTitle 
}

If you have no return type you can have -> Void or nothing. You cannot have -> without the Void.

Billy Potts
Billy Potts
Courses Plus Student 2,344 Points

thanks a lot

Devin Boddie
Devin Boddie
6,777 Points
Devin Boddie
Devin Boddie
6,777 Points

hi jcorum,

I came up with the same answer that you have however no matter what I do I cannot get the system to compile.

any advice?

Devin Boddie
Devin Boddie
6,777 Points
Devin Boddie
Devin Boddie
6,777 Points

func lend () throws { throw BookError.IncorrectTitle }

This was the code I came up with however for some reason I must still be doing something incorrect as I'm still not able to pass the challenge.

Joshua Hardy
Joshua Hardy
17,317 Points
Joshua Hardy
Joshua Hardy
17,317 Points 
func lend() throws {
    throw BookError.incorrectTitle
}
Joshua Hardy
Joshua Hardy
17,317 Points

the 'i' in .incorrectTitle needs to be lowercase.