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iOS Error Handling in Swift 2.0 Error Handling Handling Errors

Nikita Voloboev
Nikita Voloboev
4,816 Points
Posted by Nikita Voloboev
Nikita Voloboev
4,816 Points

I am really confused about this exercise, I kind of understand what is being asked but not sure about implementation.

I am not sure what I need to do in the guard let statements in the function body and if I even need to pass the dict parameter into the function as the problem description does not say so.

I would appreciate any help. Thank you. :)

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

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

    func parse(dict: [String : String]) throws {
        guard let data == nil else {
            throw ParserError.EmptyDictionary
        }
    }
}

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

1 Answer

jcorum
jcorum
71,830 Points
jcorum
jcorum
71,830 Points

Nikita, try this:

    func parse() throws {
        if data == nil {
            throw ParserError.EmptyDictionary
        }

        if data!["someKey"] == nil {
            throw ParserError.InvalidKey
        }
    }

Note that the parse() function doesn't take any parameters.