errors/gcs0311-3.cs

   1 // CS0311: The type `B' cannot be used as type parameter `T' in the generic type or method `Foo<T>'. There is no implicit reference conversion from `B' to `A'
   2 // Line: 35
   3 using System;
   4
   5 public class Foo<T>
   6         where T : A
   7 {
   8         public void Test (T t)
   9         {
  10                 Console.WriteLine (t);
  11                 Console.WriteLine (t.GetType ());
  12                 t.Hello ();
  13         }
  14 }
  15
  16 public class A
  17 {
  18         public void Hello ()
  19         {
  20                 Console.WriteLine ("Hello World");
  21         }
  22 }
  23
  24 public class B
  25 {
  26         public static implicit operator A (B b)
  27         {
  28                 return new A ();
  29         }
  30 }
  31
  32 class X
  33 {
  34         Foo<B> b;
  35
  36         static void Main ()
  37         {
  38         }
  39 }