Why do I get “Static member '…' cannot be used on instance of type '…'” error?

Question

Here is a straightforward use of a static member inside an instance method:

public struct RankSet {
    private let rankSet : UInt8
    static let counts : [UInt         


        

Answer 1

The error message is misleading: static members can be accessed from any piece of code that has proper visibility to them, which includes instance methods.

However, Swift does not provide a short name access to static members from instance methods - a common feature of many other programming languages. This is what is causing the error above.

Swift insists on fully qualifying names of static members, as follows:

public var count : Int {
    get {
        return Int(RankSet.counts[Int(rankSet)])
        //         ^^^^^^^^
    }
}