[Vala] idiomatic way to pass an array for modification to a function

[Dan Hitt <dan hitt gmail com>]

I've been struggling to write a function that can modify an array it
receives as an argument.

Now, as it happens, it looks like you can just write it like it were
C, using pointers.

So this code works and does what i expect:

    void main( ) {
            var t = new int[6];
            change_values(t, 0);
            change_values(t, 3);
            for (var i=0; i<t.length; i++)
                    stdout.printf("%d -> %d\n",i,t[i]);
    }

    void change_values(int *w,int loc) {
            w[loc+0]=1;
            w[loc+1]=2;
            w[loc+2]=3;
    }

However, it doesn't use 'ref' and i would like to write something more
idiomatic.

The constraint is that i really do want to have reference-type semantics with
no unnecessary copying because the actual application will involve a routine
called many times on a long input array.

Thanks in advance for any clues on how to make this more stylistic, or any good
but detailed references.  (This subject seems to come up from time to
time, but the
answers are never quite detailed enough for me to comprehend.)

dan