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iOS Error Handling in Swift Error Handling Handling Errors

Adam Petritsis
Adam Petritsis
2,942 Points
Posted by Adam Petritsis
Adam Petritsis
2,942 Points

Do i need to create a new func outside the struct for this problem or use the do/catch inside the struct?

Now that you have good error handling code, let's call the parse method. Remember that since this is a throwing function, you will need to use a do catch block. For this task, just use a generic catch block rather than pattern matching on specific errors. In the catch clause, simply log an error message of your choosing.

error.swift 
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)