public object Convert(object value, Type targetType, object parameter, CultureInfo culture)
        {
            if (Equals(value, TrueWhenEqualTo))
            {
                return(Boxes.True);
            }

            if (Equals(value, FalseWhenEqualTo))
            {
                return(Boxes.False);
            }

            return(Boxes.For(Default));
        }