CODEWITHSUNDEEP
swiftswift2
donkey
donkey

Reputation: 4363

How to silence "Default will never be executed" in Swift 2.0

I have a switch statement that shows different banners according to a type variable.

switch type {   
        case HPBannerType.NetworkUnavailableBanner:
            break
        case HPBannerType.LocationServiceUnavailableBanner:
            break
        case HPBannerType.LocationServiceDisabledBanner:
            break  
        default:
            break
}

The type variable is of type HPBannerType which is an enum:

enum HPBannerType: String{
    case NetworkUnavailableBanner = "HPNetworkUnavailableBanner"
    case LocationServiceUnavailableBanner = "HPLocationServiceUnavailableBanner"
    case LocationServiceDisabledBanner = "HPLocationServiceDisabledBanner"
}

There isn't quite a default type out of 3 types. When I write the switch statement, I have to list all of the cases for clearer understanding. This leaves the ending "default" state an useless state and shows the warning.

Default will never be executed

How could I silence this warning?

EDIT:

@Eric D. has absolute the right solution. But the reason I posted this is because

at first, I did not use the shorthand form .XXX but the complete form HPBannerType.XXX, when I remove the default tag, XCode gave me 200 errors!

So to correct this problem, you HAVE to use shorthand form to allow XCode to recognize if its exhaustive switch statement! Or you will get error. You can try the following:

switch type {
        case HPBannerType.NetworkUnavailableBanner:
            break
        case HPBannerType.LocationServiceUnavailableBanner:
            break
        case HPBannerType.LocationServiceDisabledBanner:
            break
 }

This will raise error!

Upvotes: 3

Views: 3498

Answers (1)

Eric Aya
Eric Aya

Reputation: 70098

You don't need to include default when switching over your enum because the compiler knows the switch is exhaustive (you've covered all cases):

switch type {
case HPBannerType.NetworkUnavailableBanner:
    break
case HPBannerType.LocationServiceUnavailableBanner:
    break
case HPBannerType.LocationServiceDisabledBanner:
    break
}

As @vadian commented, you can also use a shorter syntax, because the compiler already knows that type is an enum of type HPBannerType:

switch type {
case .NetworkUnavailableBanner:
    break
case .LocationServiceUnavailableBanner:
    break
case .LocationServiceDisabledBanner:
    break
}

Upvotes: 10

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