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wwyattw
10,389 PointsI don't quite understand how to get the empty key property. Can someone help?
To get a list of keys in a dictionary you can use the keys property which returns an array. Use the contains method on it to check if the value exists in the array
enum ParserError: Error { case emptyDictionary case invalidKey }
struct Parser { var data: [String : String?]?
func parse() throws {
guard let emptyDictionary = data else { throw ParserError.emptyDictionary }
guard let invalidKey = data?.keys.contains("someKey") else { throw ParserError.invalidKey }
}
}
let data: [String : String?]? = ["someKey": nil] let parser = Parser(data: data)
enum ParserError: Error {
case emptyDictionary
case invalidKey
}
struct Parser {
var data: [String : String?]?
func parse() throws {
guard let emptyDictionary = data else { throw ParserError.emptyDictionary }
guard let invalidKey = data?.keys.contains("someKey") else { throw ParserError.invalidKey }
}
}
let data: [String : String?]? = ["someKey": nil]
let parser = Parser(data: data)
1 Answer
Mitchell Richmond
5,401 PointsI found this was a much easier way to do it and the challenge accepts it.
guard data != nil else { throw ParserError.emptyDictionary }
guard (data?["someKey"]) != nil else {
throw ParserError.invalidKey
}