     /**
     The value of the alpha component of the current color.
     
+        let c = C4Color()
+        let alphaVal = c.alpha
+
     :returns: Double value in the range [0.0 ... 1.0]
     */
     public var alpha: Double {

    
    /**
    Initializes and returns a new C4Color object based on specified color values.

    :param: red The red value for the new color [0 ... 255]
    :param: green The green value for the new color [0 ... 255]

    /**
    Initializes and returns a new C4Color object based on a provided UIColor object.
    
        let c = C4Color(UIColor.redColor())

    :param: color A UIColor object whose components will be extrated to create a new C4Color.
    */
    public convenience init(_ color: UIColor) {
