public static Map<TensorAddress, ScalarFunction<Reference>> wrapScalars(Map<TensorAddress, ExpressionNode> nodes) {
        Map<TensorAddress, ScalarFunction<Reference>> functions = new LinkedHashMap<>();
        for (var entry : nodes.entrySet())
            functions.put(entry.getKey(), wrapScalar(entry.getValue()));
        return functions;
    }
Returns the tensor function wrapped by this
searchlib/src/main/java/com/yahoo/searchlib/rankingexpression/rule/TensorFunctionNode.java