Do int ref parameter get boxed?

Question

Say I have the following code:

void Main()
{
    int a = 5;
    f1(ref a);
}

public void f1(ref int a)
{
    if(a > 7) return;
    a++;
    f1(ref a);
    Co         


        

Answer 1

It's easy to create a program that could give different results depending on whether ref int gets boxed:

static void Main()
{
    int a = 5;
    f(ref a, ref a);
}

static void f(ref int a, ref int b)
{
    a = 3;
    Console.WriteLine(b);
}

What do you get? I see 3 printed.

Boxing involves creating copies, so if ref a were boxed, the output would have been 5. Instead, both a and b are references to the original a variable in Main. If it helps, you can mostly (not entirely) think of them as pointers.