[rules-users] keep only one, retract all other

[Wolfgang Laun]

You cannot use an interfact (List) to instantiate an object, which
is happening due to the collect.
--W

On 30/11/2012, Martin Minka <martin.minka at gmail.com> wrote:
> I want to keep only 1 fact with id=="aaaa". But this is not working:
>
> rule "leave only one"
> when
>     $removeUs : java.util.List(size>1)
>         from collect(Fact(id=="aaaa")
> then
>     size = $removeUs.size();
>     for (int i=1; i < size; i++) {
>         retract($removeUs.get(i));
>     }
> end
>