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iOS Error Handling in Swift 2.0 Error Handling Throwing Errors

Sheng Wei
Sheng Wei
4,382 Points
Posted by Sheng Wei
Sheng Wei
4,382 Points

[Help!] Whats wrong with this simple Error Handling Statement?

Hi there,

Im not sure what the correct syntax is, and do I need a guard statement? If so, I'm not sure what goes before "else"

error.swift 
enum BookError: ErrorType {
  case IncorrectTitle
}

func lend() throws {

    guard case IncorrectTitle = "n" else {
    throw BookError.IncorrectTitle("Failed")
    }
 }

1 Answer

Damien Watson
Damien Watson
27,419 Points
Damien Watson
Damien Watson
27,419 Points

Hi Sheng,

You just need to throw the error, you don't need to do anything else.

enum BookError: ErrorType {
  case IncorrectTitle
}

func lend() throws {
  throw BookError.IncorrectTitle
}