erlang中的数据结构

.gb_tree

1>X = gb_trees:from_orddict(orddict:from_list([{trace,false},{limit,-1},{timeout,-1}])).
{3,{timeout,-1,{limit,-1,nil,nil},{trace,false,nil,nil}}}
2>gb_trees:update(limit,true,X).                                                      {3,{timeout,-1,{limit,true,nil,nil},{trace,false,nil,nil}}}