@Test
public void functionTest4() {

    String ruleCode = "set col: speed value: ismissing('')";
    RuleVisitorParser parser = new RuleVisitorParser();
    Set setRule = (Set) parser.parse(ruleCode);
    ExprEval exprEval = ((Expr)setRule.getValue()).eval(null);
    System.out.println(exprEval.toString());
    //assertEquals("3600", exprEval.asString().substring(0,4));
}