@Override
    public Value evaluate(Context context) {
        if (getCondition().evaluate(context).asBoolean())
            return getTrueExpression().evaluate(context);
        else
            return getFalseExpression().evaluate(context);
    }
The average probability that the condition of this node will evaluate to true, or null if not known
searchlib/src/main/java/com/yahoo/searchlib/rankingexpression/rule/IfNode.java