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iOS Error Handling in Swift Error Handling Handling Errors

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

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)
}