SetupOnce

@objc
public protocol SetupOnce

Simplifies work with classes that need some routine to be performed once on app load.

It’s behaviour is close to [NSObject load] but since overriding [NSObject load] method can’t be used in Swift you may use this protocol instead.

Using property assures code will never be executed twice.

static var setupOnce: Int = {
    // This code will be called once on app start
    return 0
}()