Loading a clip that does not actually exist

Edit: k I totally screwed up this problem, sorry guys I’ll be making a new thread with a clearer question

Hi

In my application I have a class Map, which is an as file that extends MovieClip. Map is used by the document class Core. I have multiple .fla files whose document classes all extend Map, and in each .fla, in the library, there’s clip map_1, map_2, map_3, etc. Now I load one of these maps into Core.

Map has a method addFirst():
public function addFirst(){
stg.addChild(new map_1())
}

but this generates the error “Variable Map_1 is not defined” when I use it in Core, I guess it’s because in Map itself map_1 is not defined, but it is in every children.
How do I solve this problem?