using System;

class Tests {

	struct TestStruct {
		public int i;

		public TestStruct (int i) {
			this.i = i;
		}
	}

	static int Main ()
	{
		return TestDriver.RunTests (typeof (Tests));
	}
	
	public static int test_1_nullable_unbox ()
	{
		return Unbox<int?> (1).Value;
	}

	public static int test_1_nullable_unbox_null ()
	{
		return Unbox<int?> (null).HasValue ? 0 : 1;
	}

	public static int test_1_nullable_box ()
	{
		return (int) Box<int?> (1);
	}

	public static int test_1_nullable_box_null ()
	{
		return Box<int?> (null) == null ? 1 : 0;
	}

	public static int test_1_isinst_nullable ()
	{
		object o = 1;
		return (o is int?) ? 1 : 0;
	}

	/* FIXME: This doesn't work yet

	public static int test_1_nullable_unbox_vtype ()
	{
		return Unbox<TestStruct?> (new TestStruct (1)).Value.i;
	}

	public static int test_1_nullable_unbox_null_vtype ()
	{
		return Unbox<TestStruct?> (null).HasValue ? 0 : 1;
	}

	public static int test_1_nullable_box_vtype ()
	{
		return ((TestStruct)(Box<TestStruct?> (new TestStruct (1)))).i;
	}

	public static int test_1_nullable_box_null_vtype ()
	{
		return Box<TestStruct?> (null) == null ? 1 : 0;
	}

	public static int test_1_isinst_nullable_vtype ()
	{
		object o = new TestStruct (1);
		return (o is TestStruct?) ? 1 : 0;
	}
	*/

	static object Box<T> (T t)
	{
		return t;
	}
	
	static T Unbox <T> (object o) {
		return (T) o;
	}
}