C# (CSharp) Overload Irrational примеры использования

Пример #1

 public override Expression Add(Irrational f)
 {
     return(new Irrational(value + f.value));
 }

Пример #2

 public virtual Expression Add(Irrational e)
 {
     return(new Error(this, "Don't support adding " + e.GetType().Name));
 }