public void ContravarianceTest()
{
ContravarianceDelegate <BaseClass> b = input => input.Update();
// ContravarianceDelegate<BaseClass> => ContravarianceDelegate<DerivedClass>로 implicit conversion.
// 반대로는 불가능.
ContravarianceDelegate <DerivedClass> d = b;
}
private static void ContravarianceInvoke()
{
ContravarianceDelegate del = TextWriterMethod;
TextWriter tw = null;
Console.WriteLine("Invoking Contravariance");
del((StreamWriter)tw);
}
