public bool Equals(Quality other) { return(_value == other._value); }
protected void Devaluate() { _quality = new Quality(0); }
protected void IncreaseQuality() { _quality = _quality.Increase(); }
protected void DecreaseQuality() { _quality = _quality.Decrease(); }
protected Item(string name, Days shelfLife, Quality quality) { _name = name; _quality = quality; _shelfLife = shelfLife; }