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Oliver Duncan
16,642 PointsNot sure how to check if key does not exist.
I'm not sure how to use the contains method on the data.keys array to check if the key exists.
enum ParserError: ErrorType {
case EmptyDictionary
case InvalidKey
}
struct Parser {
var data: [String : String?]?
func parse() throws {
guard let data = self.data else {
throw ParserError.EmptyDictionary
}
//??? {
throw ParserError.InvalidKey
}
}
let data: [String : String?]? = ["someKey": nil]
let parser = Parser(data: data)
1 Answer

Krzysztof Growinski
8,405 PointsHi, try this:
if data.keys.contains("someKey") {
} else { throw ParserError.InvalidKey }
Oliver Duncan
16,642 PointsOliver Duncan
16,642 PointsAh, they were asking to literally pass in "someKey". I missed that by a mile. Thanks!