C# (CSharp) FightCharacters.NullableSum примеры использования

Пример #1

 public long?GetDamageTypeDamage(DamageType damageType) => FightCharacters.NullableSum(c => c.GetDamageTypeDamageDone(damageType));

Пример #2

 public int?GetDamageTypeHits(DamageType damageType) => FightCharacters.NullableSum(c => c.GetDamageTypeHitsDone(damageType));