ds_map_deep_clone

map = ds_map_create();                  //      resulting map D:
map[? "Hello"] = "World";               //      {
map[? "Goodbye"] = "Cruel World";       //          Hello: "World"
                                        //          Goodbye: "Cruel World"
clone = ds_map_create();                //          Clone: 
                                        //          {
ds_map_copy(clone, map);                //              Hello: "World"
                                        //              Goodbye: "Cruel World"
map[? "Clone"] = clone;                 //              Yesterday: "Tomorrow" 
map[? "Zero"] = "Infinity";             //          }
clone[? "Yesterday"] = "Tomorrow";      //          Zero: "Infinity"
                                        //      }
D = ds_map_deep_clone(map);

COPY/// @func   ds_map_deep_clone(map)
///
/// @desc   Clones a map deeply to a new copy,
///         cloning any nested maps and lists,
///         and returning the created root map.
///
/// @param  {map}       map         map to clone
///
/// @return {map}       deep-cloned map
///
/// GMLscripts.com/license

function ds_map_deep_clone(map)
{
    var json = json_encode(map);
    var clone = json_decode(json);
    return clone;
}