@Override
// TODO: recursive expressions as operands
public boolean process(
ProvaReagent prova,
ProvaDerivationNode node,
ProvaGoal goal,
List<ProvaLiteral> newLiterals,
ProvaRule query) {
ProvaLiteral literal = goal.getGoal();
List<ProvaVariable> variables = query.getVariables();
ProvaList terms = (ProvaList) literal.getTerms().cloneWithVariables(variables);
ProvaObject[] data = terms.getFixed();
if (data.length != 3) return false;
ProvaObject lt = data[0];
if (lt instanceof ProvaVariablePtr) {
ProvaVariablePtr varPtr = (ProvaVariablePtr) lt;
lt = variables.get(varPtr.getIndex()).getRecursivelyAssigned();
}
if (!((lt instanceof ProvaVariable) || (lt instanceof ProvaConstant))) return false;
ProvaObject a1 = data[1];
if (a1 instanceof ProvaVariablePtr) {
ProvaVariablePtr varPtr = (ProvaVariablePtr) a1;
a1 = variables.get(varPtr.getIndex()).getRecursivelyAssigned();
}
if (!(a1 instanceof ProvaConstant)) return false;
Object oa1 = ((ProvaConstant) a1).getObject();
if (!(oa1 instanceof Number)) return false;
ProvaObject a2 = data[2];
if (a2 instanceof ProvaVariablePtr) {
ProvaVariablePtr varPtr = (ProvaVariablePtr) a2;
a2 = variables.get(varPtr.getIndex()).getRecursivelyAssigned();
}
if (!(a2 instanceof ProvaConstant)) return false;
Object oa2 = ((ProvaConstant) a2).getObject();
if (!(oa2 instanceof Number)) return false;
Number na1 = (Number) oa1;
Number na2 = (Number) oa2;
Number result;
if (na1 instanceof Double || na2 instanceof Double)
result = na1.doubleValue() * na2.doubleValue();
else if (na1 instanceof Float || na2 instanceof Float)
result = na1.floatValue() * na2.floatValue();
else if (na1 instanceof Long || na2 instanceof Long) result = na1.longValue() * na2.longValue();
else if (na1 instanceof Integer || na2 instanceof Integer)
result = na1.intValue() * na2.intValue();
else result = na1.byteValue() * na2.byteValue();
if (lt instanceof ProvaConstant) return ((ProvaConstant) lt).getObject() == result;
((ProvaVariable) lt).setAssigned(ProvaConstantImpl.create(result));
return true;
}
@Override
public boolean process(
ProvaReagent prova,
ProvaDerivationNode node,
ProvaGoal goal,
List<ProvaLiteral> newLiterals,
ProvaRule query) {
ProvaLiteral literal = goal.getGoal();
List<ProvaVariable> variables = query.getVariables();
ProvaList terms = (ProvaList) literal.getTerms().cloneWithVariables(variables);
ProvaObject[] data = terms.getFixed();
if (data.length != 1 || !(data[0] instanceof ProvaList)) return false;
String symbol = ((ProvaConstant) ((ProvaList) data[0]).getFixed()[0]).getObject().toString();
ProvaLiteral lit = kb.generateLiteral(symbol, ((ProvaList) data[0]).getFixed(), 1);
// This automatically adds the rule to the respective predicate in the knowledge base
kb.generateRuleA(lit, new ProvaLiteral[] {});
return true;
}