Error with nested maps

[g-argyropoulos]

While trying out the map feature of generate_parameter_library, I encountered a compilation error with nested maps. A minimal example is the following:

queries_list: {
    type: string_array,
  }

  queries:
    __map_queries_list:    
      arguments: {
        type: string_array,
      }
      __map_arguments:       
        command: {
          type: string,
        }    

The output looks like that:

In member function ‘void foo::ParamListener::refresh_dynamic_parameters()’:
error: ‘struct foo::Params’ has no member named ‘arguments’
  153 |       for (const auto & value : updated_params.arguments){
      |                                                ^~~~~~~~~
error: ‘struct foo::Params::Queries’ has no member named ‘__map_queries_list’; did you mean ‘MapQueriesList’?
  154 |           auto& entry = updated_params.queries.__map_queries_list.arguments_map[value];
      |                                                ^~~~~~~~~~~~~~~~~~
      |                                                MapQueriesList
In member function ‘rcl_interfaces::msg::SetParametersResult foo::ParamListener::update(const std::vector<rclcpp::Parameter>&)’:
error: ‘struct foo::Params’ has no member named ‘arguments’
  187 |         for (const auto & value : updated_params.arguments){
      |                                                  ^~~~~~~~~
error: ‘struct foo::Params::Queries’ has no member named ‘__map_queries_list’; did you mean ‘MapQueriesList’?
  190 |                 updated_params.queries.__map_queries_list.arguments_map[value].command = param.as_string();
      |                                        ^~~~~~~~~~~~~~~~~~
      |                                        MapQueriesList
In member function ‘void foo::ParamListener::declare_params()’:
error: ‘struct foo::Params’ has no member named ‘arguments’
  231 |       for (const auto & value : updated_params.arguments){
      |                                                ^~~~~~~~~
error: ‘struct foo::Params::Queries’ has no member named ‘__map_queries_list’; did you mean ‘MapQueriesList’?
  232 |           auto& entry = updated_params.queries.__map_queries_list.arguments_map[value];
      |                                                ^~~~~~~~~~~~~~~~~~
      |                                                MapQueriesList

Are nested maps not supported or am I doing something wrong?

[tylerjw]

I don't have any examples of anyone else doing this. It is probably just not yet working. You are welcome to submit PRs if you want to work on making nested maps work.