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Start your free trialGokul Nishanth
245 PointsHow to get all the keys from the dictionary?
I have used this syntax:
let allKeys = Array(data.keys)
enum ParserError: Error {
case emptyDictionary
case invalidKey
}
struct Parser {
var data: [String : String?]?
func parse() throws {
guard let nilData = data?["someKey"] else {
throw ParserError.emptyDictionary
}
let keysArray = Array(data.keys)
guard let key = keysArray.contains("someKey") else {
throw ParserError.invalidKey
}
}
}
let data: [String : String?]? = ["someKey": nil]
let parser = Parser(data: data)
1 Answer
Elliot Rutherfoord
7,684 PointsHey man, I found this one daunting at first, but this is how I ultimately got it to work:
enum ParserError: Error { case emptyDictionary case invalidKey }
struct Parser { var data: [String : String?]?
func parse() throws {
guard data != nil else {
throw ParserError.emptyDictionary
}
guard (data?["someKey"]) != nil else {
throw ParserError.invalidKey
}
}
}
let data: [String : String?]? = ["someKey": nil] let parser = Parser(data: data)
do { let someData = try parser.parse() } catch ParserError.emptyDictionary { print("I'm so empty inside") } catch ParserError.invalidKey { print("I'm also an invalid") }
Gokul Nishanth
245 PointsGokul Nishanth
245 PointsThankyou.