public static int Main()
{
var b = new B();
if (b.Foo <int?> () == null)
{
return(0);
}
b.Foo2 <int?> ();
var b2 = new B2();
b2.Foo <byte> ();
var b3 = new B3();
b3.Foo <string> ();
return(1);
}