"extending" existed class

[Jarrett Billingsley]

"novice2" <sorry at noem.ail> wrote in message 
news:eh4u36$2bsc$1 at digitaldaemon.com...
> Hello.
> I have existed class (for example Stream in phobos), and i need add
> new method to it. In the past (if i correctly remember), i was able
> to do it by defining function, that accept instance of class as
> first argument, and then use it function like instance.function()
>...
> Can anyone say, what i missed, or the better way to "extend"
> existed class without declare new class based on existed?
> Thanks.

I don't think that ability has ever existed.  Maybe you're confusing it with 
the ability to do so with arrays?

int method(int[] x)
{
 return x.length;
}

void main()
{
 int[] arr = new int[10];
 int i = method(arr);
 int k = arr.method(); // equivalent to above
}