Re: [eclipse-clp-users] A complex Problem

2010/2/8 Christian Wirth <tyrion_at_geek-squad.de>:
> i have a complex problem, i dont even have a clue how to start solving it
>
> .. hopefully i can explain it somehow understandable. I have terms
> describing states of games. those are not grounded.
> The terms are like this:
> State = [location(_73, _264, _265), blockednorth(_264, _265)]
> now i want to determine all possible effects in this state with a given
> move. This can be done by this call:
> d_next(Effect,[does(Player,Move)]-State), but d_next is dynamic compiled
> out of the game description.
> .. to get all possible effects, i use
> findall(Effect,(d_next(Effect,[does(Player,Move)]-State)),Effects) (or
> bagof)
>
> .. but now i have the variables bound, and the state looks like this:
> State = [location(bomberman, 1, 1), blockednorth(_491, _492)]
> That should not happen !
>
Why?

You could first copy State term (using copy_term predicate) and use
a copy in findall.

> The only additional thing i know, that helps is this:
> If a condition is true in a given state is checked by
>
> :- mode d_true(?, +).
> d_true(F,_-Z) :-
>    member(F,Z).
>
What is a connection between d_true/2 and d_next/2 predicates? What is
F in d_next
predicate?

> my current ideas are
>
> a) get a list of all grounded facts and remove them for befor calling
> the predicate. Was not able to do this, because i dont know how to get
> the lis
>
Where are facts stored? What do you mean by removing them?

I do not see what is the algorithm. How are predicates called and what they do?
Maybe providing us with a simple example would be a good idea?

> .. i know this mailing list is not exactly the right place, but here i
> got the best answers to prolog problems till now ....
>
You can try comp.lang.prolog too.

Best regards
-- 
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