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iOS Error Handling in Swift Error Handling Handling Errors

Struggling with Error Checking

Can't figure out how to handle the dictionary with two optionals, anybody have the answer for this exercise?

Thank you!

error.swift
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)

2 Answers

enum ParserError: Error { case emptyDictionary case invalidKey }

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

func parse() throws {

guard let parserData = data else {
    throw ParserError.emptyDictionary
}

guard let keysArray = data?["someKey"] else {
    throw ParserError.invalidKey
}

} }

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

Awesome thanks. It is a bit outdated with Swift 2, but helped me figure it out, thank you! Here is my final solution that ended up working:

enum ParserError: Error { case emptyDictionary case invalidKey }

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

func parse() throws {

    guard let parserData = data else {
        throw ParserError.emptyDictionary
    }

    guard let keysArray = data?["someKey"] else {
        throw ParserError.invalidKey
    }

}

}

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