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iOS Error Handling in Swift Error Handling Handling Errors

Martel Storm
Martel Storm
4,157 Points
Posted by Martel Storm
Martel Storm
4,157 Points

Handling Errors! I can't Handle it!

Isn't this supposed to pass?

error.swift 
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]
do {
    let parser = Parser(data: data)
    try parser.parse()
} catch ParserError.EmptyDictionary {
} catch ParserError.InvalidKey {
}

1 Answer

Nathan Tallack
Nathan Tallack
22,159 Points
Nathan Tallack
Nathan Tallack
22,159 Points

Yeah, your code is good, but the workspace unit tests don't really like you changing stuff that have already coded for. In this case you changed the case of your error enum items.

Your code would look like this without those changes.

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]

do {
    let parser = Parser(data: data)
    try parser.parse()
} catch ParserError.emptyDictionary {
} catch ParserError.invalidKey {
}
Martel Storm
Martel Storm
4,157 Points
Martel Storm
Martel Storm
4,157 Points

You're basically a god. Thank you.