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Elijah Florence
Courses Plus Student 3,225 PointsHow to check if Dictionary is nil
I know I can use a guard let statement to check whether or not a key exists, but I dont remember a lesson on how to check whether or not an entire dictionary contains data? Maybe something like [key : value] ????
enum ParserError: ErrorType {
case EmptyDictionary
case InvalidKey
}
struct Parser {
var data: [String : String?]?
func parse() throws {
if let data = [nil : nil] { throw ParserError.EmptyDictionary }
guard let key = data["someKey"] else { throw ParserError.InvalidKey }
}
}
let data: [String : String?]? = ["someKey": nil]
let parser = Parser(data: data)
1 Answer
Jari Koopman
Python Web Development Techdegree Graduate 29,349 PointsHi Elijah,
If you want to get what I think you want to get (just checking if there's anything in the dictionary) you can just use the not operator like this:
var dict: [String: AnyObject]
if dict != nil {
//Now you know it's not nil, so it contains someting
}
Hope this helped!
Kind regards, Jari