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iOS Error Handling in Swift Error Handling Handling Errors

my do catch block is giving me errors, what am I doing wrong?

Im looking over my notes on how to create a do catch block and I can't see what im doing wrong

enum ParserError: Error {
  case emptyDictionary
  case invalidKey

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

  func parse() throws {
    guard let incomingData = data else { throw ParserError.emptyDictionary }

    guard incomingData.keys.contains("someKey") else { throw ParserError.invalidKey }

  do { try parse()

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

do {
  let attempt = try parse()
 catch ParserError {

1 Answer

Johnny Nguyen
Johnny Nguyen
3,875 Points

You did really good at task 1. These below are task 2 and 3. Look at the code and the task to improve your understanding. Good Luck!

Challenge task 2 of 3

do {
try parser.parse()
} catch let error {

Challenge task 3 of 3

do {
try parser.parse()
} catch ParserError.emptyDictionary {
} catch ParserError.invalidKey {