Leafdown                Leafdown R6 Class
assert_join_map_levels_by
                        Check whether the given join_map_levels_by is
                        valid
assert_spdf_list        Check whether the given spdf_list is a valid
                        spdf_list and has all the required params.
check_draw_ellipsis     Checks for undesired arguments in ellipsis in
                        $draw_leafdown method
gdp_2014_admin_districts
                        GPD for administrative districts of Germany for
                        2014.
gdp_2014_federal_states
                        GPD for federal states of Germany for 2014.
us_election_counties    Results of the 2016 US Presidential Election -
                        County Level
us_election_states      Results of the 2016 US Presidential Election -
                        State Level
