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Start your free trialTim Watkins
16,034 PointsNeed help with errors
enum ParserError: Error { case emptyDictionary case invalidKey }
struct Parser { var data: [String : String?]?
func parse() throws {
guard let dict = data else { throw ParserError.emptyDictionary }
guard dict.keys.contains("someKey") else { throw ParserError.invalidKey }
}
let data: [String : String?]? = ["someKey": nil] let parser = Parser(data: data)
do { let parsed = try parser.parse() } catch ParserError.emptyDictionary { print("Empty Dictionary!") } catch ParserError.invalidKey { print("Invalid Key!") }
enum ParserError: Error {
case emptyDictionary
case invalidKey
}
struct Parser {
var data: [String : String?]?
func parse() throws {
guard let dict = data else { throw ParserError.emptyDictionary }
guard dict.keys.contains("someKey") else { throw ParserError.invalidKey }
}
let data: [String : String?]? = ["someKey": nil]
let parser = Parser(data: data)
do {
let parsed = try parser.parse()
} catch ParserError.emptyDictionary {
print("Empty Dictionary!")
} catch ParserError.invalidKey {
print("Invalid Key!")
}
1 Answer
Aniruddha Shukla
2,846 PointsI would refine your try catch block. You can declare your constant error in the catch block. Something like this
do {
try parser.parse()
} catch(let error) {
switch error {
case ParserError.emptyDictionary:
print("Empty Dictionary")
case ParserError.invalidKey:
print("Invalid Key")
default:
print("Some other error")
}
}
Tim Watkins
16,034 PointsTim Watkins
16,034 PointsAwesome! Thanks that works