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iOS Error Handling in Swift 2.0 Error Handling Handling Errors

Aaron Glaesemann
Aaron Glaesemann
11,303 Points
Posted by Aaron Glaesemann
Aaron Glaesemann
11,303 Points

Is the error in my code or the constants at the bottom? I'm having a hard time figuring out exactly what is wrong.

So when I run it in Xcode, it appears that the code that I wrote runs. Perhaps the code that I wrote is messing up the constants data and parser?

error.swift 
enum ParserError: ErrorType {
  case EmptyDictionary
  case InvalidKey
}

struct Parser {
  var data: [String : String?]?

  func parse() throws {

  }
}

let data: [String : String?]? = ["someKey": nil]
let parser = Parser(data: data)
Aaron Glaesemann
Aaron Glaesemann
11,303 Points
Aaron Glaesemann
Aaron Glaesemann
11,303 Points

I think I almost have it figured out. I need to use the "do catch" statement.

Antonija Pek
Antonija Pek
5,819 Points

This is complete code which passes this challenge, hope it helps.

enum ParserError: ErrorType {
    case EmptyDictionary
    case InvalidKey
}

struct Parser {
    var data: [String : String?]?

    func parse() throws {
        guard let data = data else {
            throw ParserError.EmptyDictionary
        }

        guard let key = data["somekey"] else {
            throw ParserError.InvalidKey
        }

    }
}

let data: [String : String?]? = ["someKey": nil]
let parser = Parser(data: data)

do {
    try parser.parse()
} catch {
    ParserError.EmptyDictionary
} catch {
    ParserError.InvalidKey
}
Aaron Glaesemann
Aaron Glaesemann
11,303 Points
Aaron Glaesemann
Aaron Glaesemann
11,303 Points

Thanks, Antonia! I appreciate the help.