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iOS Error Handling in Swift Error Handling Handling Errors

Posted by perpetual makayi
perpetual makayi
8,441 Points

error handling in swift 3

enum ParserError: Error { case EmptyDictionary case InvalidKey }

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

func parse() throws {
    guard let parsedData = data else {
        throw ParserError.EmptyDictionary
    }
    guard parsedData.keys.contains("someKey") else {
        throw ParserError.InvalidKey
    }
}

}

let data: [String : String?]? = ["someKey": nil]

do { let parser = try Parser(data: data) parser.parse() } catch ParserError.EmptyDictionary {

} can anyone help my error is in the line that says parse.parse()

error.swift 
enum ParserError: Error {
    case EmptyDictionary
    case InvalidKey
}

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

    func parse() throws {
        guard let parsedData = data else {
            throw ParserError.EmptyDictionary
        }
        guard parsedData.keys.contains("someKey") else {
            throw ParserError.InvalidKey
        }
    }
}

let data: [String : String?]? = ["someKey": nil]


do {
    let parser = try Parser(data: data)
    parser.parse()
} catch ParserError.EmptyDictionary {

}

1 Answer

Jeff McDivitt
Jeff McDivitt
23,970 Points
Jeff McDivitt
Jeff McDivitt
23,970 Points 
enum ParserError: Error {
  case emptyDictionary
  case invalidKey
}

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

    func parse() throws {

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