Re: [gnugo-devel] attack5

[Evan Berggren Daniel]

On Mon, 11 Nov 2002 address@hidden wrote:

> I'm skeptical of the claim that you don't need defend5 but I haven't
> thought through this carefully.

You do need defend5.

The reason is that attack() and find_defense() need to be consistent.  The
reason the original patch worked was that I forgot to change the line in
attack() that returns immediately if there are more than 4 liberties.
Which meant that attack() would not attack things with 5 liberties, but
do_attack() would.  The result was that strings that started with 5
liberties would not be attacked, but that strings that could gain a fifth
liberty in defending themselves would be.  I actually think that might be
an interesting heuristic, for the simple reason that we can't try a
tactical attack and then an owl_attack.  But, that wasn't the intent, and
I don't think it's a great idea.

So, my current work includes a defend5 function.

Evan Daniel