/**
* Constructor.
*
* @param engine the engine which is calling this interpreter
* @param goal the query to be satisfied
* @param clauses the set of code blocks needed to implement this goal
* @param isTop true if this is a top level call from the outside iterator, false means it is an
* internal generator call which means we don't need to insert an tabled call
*/
public LPInterpreter(
LPBRuleEngine engine, TriplePattern goal, List<RuleClauseCode> clauses, boolean isTop) {
this.engine = engine;
this.goal = goal; // Used for debug only
// Construct dummy top environemnt which is a call into the clauses for this goal
if (engine.getDerivationLogging()) {
envFrame = new EnvironmentFrameWithDerivation(RuleClauseCode.returnCodeBlock);
} else {
envFrame = new EnvironmentFrame(RuleClauseCode.returnCodeBlock);
}
envFrame.allocate(RuleClauseCode.MAX_PERMANENT_VARS);
HashMap<Node, Node> mappedVars = new HashMap<>();
envFrame.pVars[0] = argVars[0] = standardize(goal.getSubject(), mappedVars);
envFrame.pVars[1] = argVars[1] = standardize(goal.getPredicate(), mappedVars);
envFrame.pVars[2] = argVars[2] = standardize(goal.getObject(), mappedVars);
if (engine.getDerivationLogging()) {
((EnvironmentFrameWithDerivation) envFrame).initDerivationRecord(argVars);
}
if (clauses != null && clauses.size() > 0) {
if (isTop && engine.getRuleStore().isTabled(goal)) {
setupTabledCall(0, 0);
// setupClauseCall(0, 0, clauses);
} else {
setupClauseCall(0, 0, clauses, goal.isGround());
}
}
// TripleMatchFrame tmFrame = new TripleMatchFrame(this);
topTMFrame = new TopLevelTripleMatchFrame(this, goal);
topTMFrame.linkTo(cpFrame);
topTMFrame.setContinuation(0, 0);
cpFrame = topTMFrame;
}
/** Return a dereferenced copy of a triple. */
public static Triple deref(TriplePattern t) {
if (t == null) return null;
return new Triple(deref(t.getSubject()), deref(t.getPredicate()), deref(t.getObject()));
}