private static void OptionalInterfaceDemo()
{
Console.WriteLine("\n*** Optional Interface Demo:");
Person jill = new Person("Jill", 19, Color.Red); // Has a car
Option <Car> jillsCar = jill.TryGetCar(); // Some
if (jillsCar is Some <Car> some1)
{
PrintName(some1);
}
Option <ICar> abstractCar =
jill.TryGetCar().OfType <ICar>(); // Some<ICar>
if (abstractCar is Some <ICar> someOther)
{
PrintAbstractName(someOther.Content);
}
}
private static void MappingDemo()
{
Console.WriteLine("\n*** Mapping demo:");
Person child = new Person("Jill", 12, Color.Red);
Person grownUp = new Person("Joe", 46, Color.Blue);
Option <Car> none = child.TryGetCar(); // None
Option <Car> some = grownUp.TryGetCar();
Console.WriteLine($"{none}, {some}");
Option <Person> noPerson = None.Value;
Option <Person> someChild = child;
Option <Person> someGrownUp = grownUp;
Option <Car> noCar = noPerson.MapOptional(person => person.TryGetCar());
Option <Car> noChildCar = someChild.MapOptional(person => person.TryGetCar());
Option <Car> someGrownUpCar = someGrownUp.MapOptional(person => person.TryGetCar());
Console.WriteLine($"{noCar}, {noChildCar}, {someGrownUpCar}");
}