             return nil
         }
 
+        
         returnString += ", green: "
         if let modifiedString = numberFormatter.stringFromNumber( Double ( color.greenComponent ) ) {
             returnString += modifiedString

        
        // Always include the alpha component as it is impossible to tell if there is
        // an extionsion to handle the creation of colours without it.
        returnString += ", alpha: \(color.alphaComponent) )"
        
        return returnString
    }

            return nil
        }
        
        
        numberFormatter.maximumFractionDigits = ColorBuilder.maximumAlphaFractionDigits

        if let modifiedString = numberFormatter.stringFromNumber( Double ( color.alphaComponent ) ) {
            returnString += " alpha:\(modifiedString)]"
        } else {
            print ( "Error converting alpha component \(color.alphaComponent) of color to a string" )
            return nil
        }
        
        return returnString
}
    
