@Override
    public MultiArgFunctionNode clone() {
        MultiArgFunctionNode obj = (MultiArgFunctionNode)super.clone();
        obj.args = new ArrayList<>();
        for (ExpressionNode node : args) {
            obj.args.add(node.clone());
        }
        return obj;
    }
<p>Perform the appropriate calculation of the arguments into a result node.</p>

@param args   A list of operands.
@param result Place to put the result.
@return True if successful, false if not.
searchlib/src/main/java/com/yahoo/searchlib/expression/MultiArgFunctionNode.java