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iOS Error Handling in Swift Error Handling Handling Errors

Help needed!

I need help to solve this

enum ParserError: Error {
  case emptyDictionary
  case invalidKey
}

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

  func parse() throws {

  }
}

let data: [String : String?]? = ["someKey": nil]
let parser = Parser(data: data)
Bruce Röttgers
Bruce Röttgers
18,211 Points

could you please format your code (refer to the markdown cheatsheet right before the post button for details (you need three backticks at the start and end

2 Answers

Here is my answer that passes all three parts of the challenge.

enum ParserError: Error {
    case emptyDictionary
    case invalidKey
}

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

    func parse() throws {
        guard let data = data else {
            throw ParserError.emptyDictionary
        }
        guard data["someKey"] != nil else {
            throw ParserError.invalidKey
        }

    }
}

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

do {
    try parser.parse()
} catch ParserError.emptyDictionary {
    print("Error: EmptyDictionary")
} catch ParserError.invalidKey {
    print("Error: InvalidKey")
}

Thanks! I solved in this way if someone wants to see other option

enum ParserError: Error {
    case emptyDictionary
    case invalidKey
}

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

    func parse() throws {
        if data?.count == nil {
            throw ParserError.emptyDictionary
        }


        if data?.keys.contains("someKey") != nil {
            throw ParserError.invalidKey
        }
    }
}

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

do {
  try parser.parse()
}catch ParserError.emptyDictionary {
    print("Error: EmptyDictionary")
} catch ParserError.invalidKey {
    print("Error: InvalidKey")
}
FANG YU
FANG YU
1,719 Points
func parse() throws {
        guard let data = data else {
            throw ParserError.emptyDictionary
        }
        guard data.keys.contains("someKey") else {
            throw ParserError.invalidKey
        }
    }