Swift: How to get the size of an enum?

Question

I have an enumeration like this:

enum SomeType: Int {
    case Base = 0
    case Expert = 1
    case Special = 2
}

What I'd like is to get the size of this enumeration, like this:

Int enumSize = sizeof(SomeType)

However, this leads to the unexpected result of "1"; what I'd like to have is "3", certainly ;-)

How may I achieve to get the 3 as result?

Thanks for your support!

• Hardy