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iOS Error Handling in Swift 2.0 Error Handling Throwing Errors

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

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
}