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iOS Error Handling in Swift 2.0 Error Handling Handling Errors

error handling error

can't compile the handling error from dictionary

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

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

  func parse() throws {
guard var data = dict[data] else {
throw ParserError.EmptyDictionary
}
guard var data = dict["somekey"] else {
throw ParserError.InvalidKey
}
  }
}

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

4 Answers

Konrad Kr贸l
Konrad Kr贸l
4,454 Points

Nope. It works perfectly fine for challenge task 1 of 3:

enum ParserError: ErrorType {
    case EmptyDictionary
    case InvalidKey
}

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

    func parse() throws {
        if let someDict = data {
            if let someData = someDict["someKey"]{
                //code here
            } else {
            throw ParserError.InvalidKey
            }
        }
        else {
        throw ParserError.EmptyDictionary
        }

    }
}

let data: [String : String?]? = ["someKey": nil]
let parser = Parser(data: data)
Konrad Kr贸l
Konrad Kr贸l
4,454 Points

Hi, first you should check if data in dictionary exists if FALSE you throw an error .EmptyDictionary if TRUE you check if value for "someKey" exists, and again if FALSE throw an error .InvalidKey like this:

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

    func parse() throws {
        if let someDict = data {
            if let someData = someDict["someKey"]{
                // TRUE statement code is not required here
            } else {
            throw ParserError.InvalidKey
            }
        }
        else {
        throw ParserError.EmptyDictionary
        }      
    }
}

thks but still giving me a ton of errors

yes, Don't know what was going on. thks Mate!