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iOS Error Handling in Swift 2.0 Error Handling Handling Errors

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

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

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

Thanks, Antonia! I appreciate the help.