public function amountOfDays(): int
    {
        return $this->end->handle()->diff($this->start->handle())->days + 1;
    }
public function amountOfDays(): int
    {
        return $this->end->handle()->diff($this->start->handle())->days + 1;
    }
public function amountOfDays ( ) : int { return $ this -> end -> handle ( ) -> diff ( $ this -> start -> handle ( ) ) -> days + 1 ; }
returns amount of days in this datespan

@return  int
returns amount of days in this datespan