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iOS Error Handling in Swift 2.0 Error Handling Handling Errors

Posted by jc laurent
jc laurent
6,351 Points

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 Król
Konrad Król
4,454 Points
Konrad Król
Konrad Król
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 Król
Konrad Król
4,454 Points
Konrad Król
Konrad Król
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
        }      
    }
}
jc laurent
jc laurent
6,351 Points
jc laurent
jc laurent
6,351 Points

thks but still giving me a ton of errors

jc laurent
jc laurent
6,351 Points
jc laurent
jc laurent
6,351 Points

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