为什么我的 for-in 循环不起作用？ 错误处理 Swift

Question

I tried a error handling function to crack the code of a safe(for example), In my thoughts the for-in loop should print all the tries which are in the array... But the thing is that just the first String of the array gets printed and the others aren`t. Can anyone tell me where is my failure?

enum SafeError: Error {
    case wrongCode
    case tooMuchTries
    case safeIsOpen
}

 struct Safe {
    var safeIsclosed: Bool
    var code: String
    var maximumTries: Int
    mutating func OpenSafe(triedCodes: [String]) throws {
        guard safeIsclosed else {
            throw SafeError.safeIsOpen
        }
        for triedCode in triedCodes {
            print("Try \(triedCode)")
            
        
            guard triedCode == code else {
                throw SafeError.wrongCode
            }
        }
        guard triedCodes.count <= maximumTries else {
            throw SafeError.tooMuchTries
        }

    print("Password was correct")
        
    }
    
}
var safe = Safe(safeIsclosed: true, code: "WD1146", maximumTries: 5)

do {
    try safe.OpenSafe(triedCodes: ["DD377789", "123456", "WD1146", "112378AADD", "DDFG4567"])
} catch SafeError.safeIsOpen {
    print("Safe is already open")
} catch SafeError.tooMuchTries {
    print("Safe is closed now, your try was wrong")
} catch SafeError.wrongCode {
    print("Wrong Password")
} catch {
    print("Error")
}

Thanks in advance!

Answer 1

Calling throw from a function terminates the execution of said function immediately. This means that as soon as the first element of triedCodes is wrong, your function terminates because a .wrongCode error is thrown.

I would suggest modifying your function such that you check whether the correct code is contained in the triedCodes array and throw an error in case it isn't. This ensures that the whole array is checked before an error is thrown.

mutating func openSafe(triedCodes: [String]) throws {
    guard safeIsclosed else {
        throw SafeError.safeIsOpen
    }

    guard triedCodes.contains(code) else {
        throw SafeError.wrongCode
    }

    guard triedCodes.count <= maximumTries else {
        throw SafeError.tooMuchTries
    }
}

Answer 2

Once you get the first exception you are out of the loop.

Try changing the struct like this:

struct Safe {
var safeIsclosed: Bool
var code: String
var maximumTries: Int

func OpenSafe(triedCode: String) throws {
    guard safeIsclosed else {
        throw SafeError.safeIsOpen
    }
    print("Try \(triedCode)")
    
    guard triedCode == code else {
        throw SafeError.wrongCode
    }
}

mutating func OpenSafe(triedCodes: [String]) throws {
    guard safeIsclosed else {
        throw SafeError.safeIsOpen
    }
    for triedCode in triedCodes {
        do {
            try safe.OpenSafe(triedCode: triedCode)
        } catch SafeError.safeIsOpen {
            print("Safe is already open")
        } catch SafeError.wrongCode {
            print("Wrong Password")
        } catch {
            print("Error")
        }
    }
    guard triedCodes.count <= maximumTries else {
        throw SafeError.tooMuchTries
    }

    print("Password was correct") 
}
}

I cannot test it right now, so I could have syntax errors.