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iOS Error Handling in Swift Error Handling Handling Errors

Sam Belcher
Sam Belcher
3,719 Points
Posted by Sam Belcher
Sam Belcher
3,719 Points

Handling Errors

I have been working on this for awhile and I'm still confused

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)

1 Answer

Maria Te
Maria Te
8,521 Points

Here was my answer to the whole code challenge and it was alright:

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")
}

If this works, please mark it as best answer

Maria Te
Maria Te
8,521 Points

Have fun coding! The rest of it can be really challenging! :-D