public void Where()
{
Nullable <int> n = 2;
Nullable <int> n0 = null;
Assert.Throws <ArgumentNullException>(() => NullableExtensions.Where <int>(n, null));
Assert.True(n.Where(i => i == 2).HasValue);
Assert.False(n.Where(i => i == 3).HasValue);
Assert.False(n0.Where(i => i == 2).HasValue);
Assert.False(n0.Where(i => i == 3).HasValue);
}
