websiteUp set to false, but does not print Failure - swift

Question

I am trying to learn Swift/Xcode and have come across an error that I can't explain.
Here is some code that should print the error code, but still prints Success even though I have changed websiteUp to false!
enum WebpageError: Error {
case success
case failure(Int)
}
func getWebpage(uRL: String, siteUp: Bool) throws -> String {
if siteUp == false {
WebpageError.failure(404)
}
return "Success"
}
let webpageURL = "http://apple.com"
let websiteUp = false
do {
let status = try getWebpage(uRL: webpageURL, siteUp: websiteUp)
print(status)
} catch {
print(error)
}
I can't spot what is wrong, as it all looks OK to me!

Answer 1

You are doing two silly things:
How can a case of an Error enum be a .success? It's for failures!
It isn't enough to say WebpageError.failure. You have to throw the error.
So:
enum WebpageError: Error {
case failure(Int) // <== look
}
func getWebpage(uRL: String, siteUp: Bool) throws -> String {
if !siteUp {
throw WebpageError.failure(404) // <== look
}
return "Success"
}
let webpageURL = "http://apple.com"
let websiteUp = false
do {
let status = try getWebpage(uRL: webpageURL, siteUp: websiteUp)
print(status)
} catch {
print(error)
}
Having said all that, let's go back to the question of why you included a .success case. Maybe your idea was to return a value signalling success or failure. That would be a Result. Like this:
enum WebpageError: Error {
case failure(Int)
}
func getWebpage(uRL: String, siteUp: Bool) -> Result<String,Error> {
return Result {
if !siteUp {
throw WebpageError.failure(404)
}
return "Success"
}
}
let webpageURL = "http://apple.com"
let websiteUp = false
let status = getWebpage(uRL: webpageURL, siteUp: websiteUp)
do {
try print(status.get())
} catch {
print(error)
}
That might be more sophisticated than you had in mind at this stage, but it's worth thinking about.