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iOS Error Handling in Swift Error Handling Handling Errors

Posted by STEVEN PENA
STEVEN PENA
13,928 Points

In the editor, you have a struct named Parser whose job is to deconstruct information from the web. The incoming data ca

am close what am i missing

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

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

    func parse() throws {
        guard let parsedData = data else {
            throw ParserError.EmptyDictionary
        }
        guard parsedData.keys.contains("someKey") else {
            throw ParserError.InvalidKey
        }
    }
}
let data: [String : String?]? = ["someKey": nil]

do {
  let parser = try Parser(data: data).parse()
} catch let error {
    print(error)
}
Joe Mayfield
Joe Mayfield
10,409 Points
Joe Mayfield
Joe Mayfield
10,409 Points

Take a look at the ParserError.EmptyDictionary and the ParserError.InvalidKey. Then compare them to the original once fixed I think it will work.

1 Answer

Otto linden
Otto linden
5,857 Points
Otto linden
Otto linden
5,857 Points

Hello! This is the code: 

enum ParserError: Error {
  case emptyDictionary
  case invalidKey
}

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

  func parse() throws {
        guard let parsedData = data else {
        throw ParserError.emptyDictionary
    }
    guard parsedData.keys.contains("someKey") else {
        throw ParserError.invalidKey
    }
  }
}

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

do {
  try parser.parse()
} catch ParserError.emptyDictionary {
    print("Help")
} catch ParserError.invalidKey {
    print("Help!")
}

(You did the do catch statement wrong!)