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Is there any easy way to translate a Prolog/ASP code into CLIPS?

Something like this one, but with CLIPS instead of Prover9: https://github.com/potassco/anthem/tree/master/examples

ciurlaro
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1 Answers1

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You can translate some of ASP into forward chaining, when the forward chaining engine allows you non-deterministic choice actions. The result will be a disjunctive head logic program. Here is an example of a little ASP program:

:- p, q, r.
{p,r}.
{q} :- p.
{r} :- p.

You can then rewrite this into forward chaining rules. For brevity we have used our (;)/2 action in the head of the forward chaining rules:

fail <= posted(p), posted(q), posted(r).
post(p); post(r) <= posted(init).
post(q) <= posted(p).
post(r) <= posted(p).

Here is a tracing Prolog execution, the code will first try p, but the constraint p, q, r will prevent this answer set element as a solution:

Jekejeke Prolog 3, Development Environment 1.3.2
(c) 1985-2018, XLOG Technologies GmbH, Switzerland

?- post(init).
    0 Call post(init) ? 
    1 Call post(p) ? 
    2 Call clause(q, true) ? 
    2 Fail clause(q, true) ? 
    2 Call post(q) ? 
    3 Call clause(p, true) ? 
    3 Exit clause(p, true) ? 
    3 Call clause(r, true) ? 
    3 Fail clause(r, true) ? 
    2 Exit post(q) ? 
    2 Call post(r) ? 
    3 Call clause(p, true) ? 
    3 Exit clause(p, true) ? 
    3 Call clause(q, true) ? 
    3 Exit clause(q, true) ? 
    3 Call fail ? 
    3 Fail fail ? 
    2 Fail post(r) ? 
    1 Fail post(p) ?

In the above clause/2 does check the bodies of the disjunctive head logic program. The Prolog interpreter will then backtrack to r as an answer set element:

    1 Call post(r) ? 
    2 Call clause(p, true) ? 
    2 Fail clause(p, true) ? 
    1 Exit post(r) ? 
    0 Exit post(init) ? 
Yes
  • Not exacly what i was looking for, but thanks anyway for the trial. Appreciated it. – ciurlaro Nov 07 '18 at 08:54
  • I checked CLIPS documentation, but couldn't find anything about choice or backtracking. Only do-for-all and such stuff. But you need a do-and-backtrack-do. Choice is the first thing that appears on the link you gave: https://github.com/potassco/anthem/blob/master/examples/choice-rules.lp –  Nov 07 '18 at 14:34