CVC4: using quantifiers in C++ interface

Question

I am trying to figure out how to code quantifiers in CVC4, using the C++ interface. Here is an example I am trying to get to run, but cannot.

int main() {
    SmtEngine smt(&em);
    smt.setLogic("AUFLIRA"); // Set the logic

    Expr three = em.mkConst(Rational(3));
    Expr  four = em.mkConst(Rational(4));

    // make the list of bound variables in CVC4
    Expr bound_var = em.mkBoundVar("x_bound",  em.integerType());
    vector<Expr> bound_vars;
    bound_vars.push_back(bound_var);
    Expr bound_var_list = em.mkExpr(kind::BOUND_VAR_LIST, bound_vars);

    Expr declare = em.mkExpr(kind::EQUAL, bound_var, three); //x_bound =3

    Expr check = em.mkExpr(kind::EQUAL, bound_var, four); //x_bound=4

    //forall x_bound, x_bound=3, the constraint I want to declare as true
    Expr expr = em.mkExpr(kind::FORALL, bound_var_list, declare); 

    smt.assertFormula(expr);
    smt.push();

    // expect to be INVALID
    // I want to check that given forall x_bound, x_bound = 3
    // then I ask CVC4: is it true that x_bound=4, or is it false?
    std::cout << "Quantifier " << smt.query(check) << std::endl;

    return 0;
}

Instead, I just get an error message:

Bound variables test
Quantifier unknown (INCOMPLETE)

But I define the quantifier as forall. What did I do wrong?

EDIT (asked https://www.andrew.cmu.edu/user/liminjia/):

Syntax is wrong. We want to know if

(forall x, x=3) IMPLIES (forall x, x=4)

is true or not. But CVC4 does not if the above formula is valid or not, because SMT solvers are not full-fledged first-order logic theorem provers.

If you want to try something that works, try in CVC4 language:

QUERY (FORALL (x:INT): x =4);

And in C++, we have

// check that forall x, x=3 is INVALID
void cvc4BoundVar() {
    std::cout << "Bound variables test" << std::endl;
    SmtEngine smt(&em);
    smt.setLogic("AUFLIRA"); // Set the logic

    Expr three = em.mkConst(Rational(3));

    Expr v_expr = em.mkBoundVar("x_bound",  em.integerType());
    vector<Expr> bound_vars;
    bound_vars.push_back(v_expr);
    Expr bound_var_list = em.mkExpr(kind::BOUND_VAR_LIST, bound_vars);

    Expr declare = em.mkExpr(kind::EQUAL, v_expr, three); //x=3

    Expr check = em.mkExpr(kind::EQUAL, v_expr, three);

    Expr expr = em.mkExpr(kind::FORALL, bound_var_list, declare); //forall x, x=3

    std::cout << "Quantifier " << smt.query(expr) << std::endl;
}