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iOS Error Handling in Swift Error Handling Cleaning Up With Defer

Solution of the Coding Challenge

Can you please upload the solution of each Coding Challenge? Sometimes we get confused so, a solution for each Coding Challenge will be helpful for us.

This is my code

enum ParserError: Error { case emptyDictionary(description: String) case invalidKey(description: String) }

struct Parser { var data: [String : String?]?

func parse() throws {
    guard let emptyDictionary = data else { throw ParserError.emptyDictionary(description: "The Dictionary has no value") }
    guard let invalidKey = data?["someKey"] else { throw ParserError.invalidKey(description: "There are no keys associated with the value") }
}

}

let data: [String : String?]? = ["someKey": nil] let parser = Parser(data: data)

do { let parser = try Parser.parse } catch ParserError.emptyDictionary(let description) { print(description) } catch ParserError.invalidKey(let description) { print(description) }

1 Answer

Here is my code:

enum ParserError: Error {

case emptyDictionary(description: String) case invalidKey(description: String) }

struct Parser { var data: [String : String?]?

func parse() throws {

guard data != nil else { throw ParserError.emptyDictionary(description: "empty dictionary") }

    guard data?.keys.contains("someKey") == true else {
        throw ParserError.invalidKey(description: "invalid key")
    }

}

}

let data: [String : String?]? = ["someKey": nil] let parser = Parser(data: data)

do { try parser.parse() } catch ParserError.emptyDictionary(let description) { print(description) } catch ParserError.invalidKey(let description) { print(description) }