pub fn old_line_range(&self) -> std::ops::Range<u32> {

        let start: u32 = self.old_line_no;

        let end: u32 = self.old_line_no + self.old_size;

    }

    pub fn new_line_range(&self) -> std::ops::Range<u32> {

        let start: u32 = self.new_line_no;

        let end: u32 = self.new_line_no + self.new_size;

    }

}