@Override
        public Double apply(List<Long> arguments) {
            MapContext context = new MapContext();
            for (int i = 0; i < type.dimensions().size(); i++)
                context.put(type.dimensions().get(i).name(), arguments.get(i));
            return evaluate(context).asDouble();
        }
Evaluate this in a context which must have the arguments bound
searchlib/src/main/java/com/yahoo/searchlib/rankingexpression/rule/GeneratorLambdaFunctionNode.java