protected boolean hasOpenChoicepoint(RuleEvaluation e) {
        Choicepoint choicepoint=e.getChoicepoint(this,false);
        if (choicepoint==null) return false; // Not tried yet
        if (!choicepoint.isOpen()) return false;
        return true;
    }
Sets whether this ellipsis condition can be referred from a production or not
container-search/src/main/java/com/yahoo/prelude/semantics/rule/EllipsisCondition.java