How to create an IBInspectable of type enum

IBInspectable.Swift

enum StatusShape:Int {
        case Rectangle
        case Triangle
        case Circle
    }

    // Programmatically: use the enum
    var shape:StatusShape = .Rectangle

    // IB: use the adapter
    @IBInspectable var shapeAdapter:Int {
        get {
            return self.shape.rawValue
        }
        set( shapeIndex) {
            self.shape = StatusShape(rawValue: shapeIndex) ?? .Rectangle
        }
    }