/**
* This function obtains from a predicate that is a conjunction of assignments the assignment
* related to an identifier
*
* @param specID The identifier of a variable in the specification
* @param pred A predicate
* @return the equality
*/
public static MemPred getRelatedEquality(Pred pred, String specID) {
AbstractRepository<Pred> predRep = pred.accept(new AndPredClausesExtractor());
AbstractIterator<Pred> predIt = predRep.createIterator();
while (predIt.hasNext()) {
Pred auxPred = predIt.next();
if (auxPred instanceof MemPred) {
MemPred memPred = ((MemPred) auxPred);
if (memPred.getMixfix()) {
String id = ((RefExpr) memPred.getLeftExpr()).getName().toString();
if (id.equals(specID)) {
return memPred;
}
} else return null;
} else return null;
}
return null;
}
/* (non-Javadoc)
* @see pea.util.z.TermToCDDVisitor#visitMemPred(net.sourceforge.czt.z.ast.MemPred)
*/
@Override
public CDD visitMemPred(MemPred pred) {
if (pred.getRightExpr() instanceof RefExpr) {
final RefExpr refExpr = (RefExpr) pred.getRightExpr();
final ZName name = refExpr.getZName();
// We replace expressions like a != b + c with NOT(a = b + c)
if (name.getOperatorName().getWord().equals(Z_NEQ_OPERATOR)) {
final ZName newRefName = factory.createZName(Z_EQUALS_OPERATOR, name.getStrokeList());
final RefExpr newRefExpr =
factory.createRefExpr(newRefName, refExpr.getZExprList(), refExpr.getMixfix());
final Pred newMemPred =
factory.createMemPred(pred.getLeftExpr(), newRefExpr, pred.getMixfix());
return newMemPred.accept(this).negate();
}
}
return visitTerm(pred);
}