How can I catch and log all errors? - swift

Question

I'm using some third-party functions, and I don't know what types of errors they can produce.
I want to catch and log all such errors, but ErrorType protocol does not have any members that could provide a meaningful message or error code. What can be done to log any type of errors properly?
do {
try someFunction()
} catch WellKnownError { // handle it }
} catch let err {
let message = ... // how can I get error type and some meaningful message from err?
NSLog(message)
}

Answer 1

I think it's not an option...
But you can try something like this...
//----------------------------------------
// Private API
//----------------------------------------
public enum CarError : ErrorType
{
case NeverTurnOn
case OutOfFuel
case Other(String)
}
public class Car
{
public func turnOn(newState:Int) throws -> Bool
{
if newState == 1
{
throw CarError.NeverTurnOn
}
else if case 2...5 = newState
{
throw CarError.OutOfFuel
}
else if newState == 10
{
throw CarError.Other("Something is gonna wrong")
}
else if newState == 11
{
throw CarError.Other(":(")
}
return false
}
}
Error Handling
func main()
{
let car = Car()
do {
try car.turnOn(4)
} catch CarError.NeverTurnOn {
print("Turn off")
} catch let err as NSError {
print(err.description)
} catch {
print("It's madness!!!")
}
}
main()
With this test... I had this result...
//Error Domain=trycatchtest.CarError Code=1 "The operation couldn’t be completed. (trycatchtest.CarError error 1.)"
//Program ended with exit code: 0
It's not the best way to solve your problem, but a new way to understand what is happening in background of this framework.
Now, asking a favor.
Please, let me now about the final result ;)
It's doesn't matter if is a good or bad result.