-// Compiler options: -langversion:future
-
using System;
interface IContravariant<in T>
return typeof (T) == typeof (object);
}
+ public static bool CovContCont<T> (ICovariant<T> e1, IContravariant<T> e2, IContravariant<T> e3)
+ {
+ Console.WriteLine (typeof (T));
+ return typeof (T) == typeof (string);
+ }
+
+ public static bool ContCovContCov<T> (IContravariant<T> e1, ICovariant<T> e2, IContravariant<T> e3, ICovariant<T> e4)
+ {
+ Console.WriteLine (typeof (T));
+ return typeof (T) == typeof (string);
+ }
+
+ public static bool CovCovCont<T> (ICovariant<T> e1, ICovariant<T> e2, IContravariant<T> e3)
+ {
+ Console.WriteLine (typeof (T));
+ return typeof (T) == typeof (string);
+ }
+
public static int Main ()
{
+
ICovariant<object> a = null;
ICovariant<string> b = null;
if (!Covariant (a, b))
if (!Contra (a_1, b_1))
return 2;
+ ICovariant<string> a_2 = null;
+ IContravariant<object> b_2 = null;
+ IContravariant<string> c_2 = null;
+ if (!CovContCont (a_2, b_2, c_2))
+ return 3;
+
+ IContravariant<object> a_3 = null;
+ ICovariant<string> b_3 = null;
+ IContravariant<string> c_3 = null;
+ ICovariant<string> d_3 = null;
+ if (!ContCovContCov (a_3, b_3, c_3, d_3))
+ return 4;
+
+ Console.WriteLine ("ok");
return 0;
}
}