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Juan Torres
7,416 Pointsi can't figure out what i'm doing wrong
i Click recheck work and it tells me to check the preview button for errors. no errors are appearing but it says it won't compile. i'm also using the playground to work out ideas to get no errors.
enum ParserError: Error {
case emptyDictionary
case invalidKey
}
struct Parser {
var data: [String : String?]?
func parse(dict: [String : String?]?) throws {
guard (dict?.keys.contains("someKey"))! else {
throw ParserError.invalidKey
}
}
}
let data: [String : String?]? = ["someKey": nil]
let parser = Parser(data: data)
1 Answer
Brandon Mahoney
iOS Development with Swift Techdegree Graduate 30,149 PointsYou should do this in a way that does not require you to force unwrap. The most concise way I've found is below.
func parse() throws {
guard data?.isEmpty == false else {
throw ParserError.emptyDictionary
}
guard (data?["someKey"]) != nil else {
throw ParserError.invalidKey
}
}
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