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Start your free trialJohn Wilcox
4,233 PointsUnwrapping needed? Where?
The compiler here keeps saying that something needs to be unwrapped.
Can someone please tell me where the error lies in my second guard statement?
Thanks,
Jack Wilcox
enum ParserError: Error {
case emptyDictionary
case invalidKey
}
struct Parser {
var data: [String : String?]?
func parse() throws {
// if no dictionary
guard let dictionary = data else {
throw ParserError.emptyDictionary
}
// if no key
guard data?.keys.contains("someKey") else {
throw ParserError.invalidKey
}
}
}
let data: [String : String?]? = ["someKey": nil]
let parser = Parser(data: data)
1 Answer
robb
5,167 PointsYou need to assign data?.keys.contains("someKey") to something:
guard let key = data?.keys.contains("someKey") else {
throw ParserError.invalidKey
}
John Wilcox
4,233 PointsJohn Wilcox
4,233 PointsHi Robb, but doesn't .contains return a Bool?
Aren't I essentially checking to see if data?.keys.contains("someKey") is true?