re-creating C++'s reference bahavior

[Derek Parnell]

On Mon, 16 Apr 2007 20:47:31 -0400, swiftcoder - Tristam MacDonald wrote:

> I am fairly new to D, from a C++ background, and I am having a
> hard time coming up with a sensible way to deal with what is
> a fairly trivial example in C++:
> ...
> But now in D, I find that the last statement requires ...

Does this below help any?

////////////////////
import std.stdio;

class Vector3f
{
    int x;
    float y;
}

class Node
{
    Vector3f m_position;  // (reference to) a Vector
    Vector3f position()   // Copy-getter
    {
        Vector3f t = new Vector3f;
        // copy fields by hand
        t.x = m_position.x;
        t.y = m_position.y;

        return t;
    }

    Vector3f* position_flds() // Reference-getter
    {
        return &m_position;
    }

    this() { m_position = new Vector3f; }
}

void main()
{
    Node n = new Node;

    writefln("A %s %s", n.position.x, n.position.y);
    n.position_flds.x = 1;
    n.position_flds.y = 2.2;
    writefln("B %s %s", n.position.x, n.position.y);

    Vector3f v = n.position;
    writefln("C %s %s", v.x, v.y);
    v.x = 10;
    v.y = 9.9;
    writefln("D %s %s", v.x, v.y);
    writefln("E %s %s", n.position.x, n.position.y);
}
///////////////////


-- 
Derek
(skype: derek.j.parnell)
Melbourne, Australia
"Justice for David Hicks!"
17/04/2007 5:30:04 PM