private Condition findIncludedCondition(String name) {
        for (Iterator<ProductionRule> i = productionRules.iterator(); i.hasNext(); ) {
            ProductionRule rule = i.next();
            if ( ! (rule instanceof IncludeDirective) ) continue;

            RuleBase included = ((IncludeDirective)rule).getIncludedBase();
            NamedCondition condition = included.getCondition(name);
            if (condition != null) return condition.getCondition();
            included.findIncludedCondition(name);
        }
        return null;
    }
Adds a named condition which can be referenced by rules
container-search/src/main/java/com/yahoo/prelude/semantics/RuleBase.java