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iOS Error Handling in Swift Error Handling Handling Errors

Hasseeb Hussain
Hasseeb Hussain
2,154 Points
Posted by Hasseeb Hussain
Hasseeb Hussain
2,154 Points

What's gone wrong?

Help!

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

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

    func parse() throws {
        guard let _ = data else {
            throw ParserError.EmptyDictionary
        }

        guard let _ = data!["someKey"] else {
            throw ParserError.InvalidKey
        }
    }
}

let data: [String : String?]? = ["someKey": nil]

do {
    let parser = try Parser(data: data).parse()
} catch {
    print("Error")
}

1 Answer

Jeff McDivitt
Jeff McDivitt
23,970 Points
Jeff McDivitt
Jeff McDivitt
23,970 Points

You switched the code given from Error to ErrorType (You should never need to adjust the code provided for the IOS course). I believe you can figure out the other errors by the code provided. Let me know if you have any questions

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 {
    let parser = try Parser(data: data)
    try parser.parse()
} catch ParserError.emptyDictionary(let description) {
    print(description)
}
catch ParserError.invalidKey(let description) {
    print(description)
}