1namespace solidware.financials.service.domain.payroll
 2{
 3    public class Vest
 4    {
 5        Fraction portion;
 6        Date vesting_date;
 7
 8        public Vest(Fraction portion, Date vesting_date)
 9        {
10            this.portion = portion;
11            this.vesting_date = vesting_date;
12        }
13
14        public Units unvested_units(Units total_units, Date date)
15        {
16            return expires_before(date) ? Units.Empty : total_units.reduced_by(portion);
17        }
18
19        bool expires_before(Date date)
20        {
21            return vesting_date.is_before(date);
22        }
23    }
24}