public void Test3()
{
Pointer <int> p1 = stackalloc int[4];
Pointer <int> p2 = stackalloc int[4];
var rg2 = new[] { 1, 2, 3, 4 };
p1.WriteAll(rg2);
p1.Copy(p2, rg2.Length);
for (int i = 0; i < rg2.Length; i++)
{
Assert.True(p1[i] == p2[i]);
}
p2.Clear(rg2.Length);
p1.Copy(p2, 1, rg2.Length - 1);
var rg1 = new[] { 2, 3, 4 };
for (int i = 1; i < rg1.Length - 1; i++)
{
Assert.True(p2[i] == p1[i + 1]);
}
}