data containers

[Moritz]

Hello,

Im currently working on a gui framework for my game, and Im trying to 
find a versatile way to build my screens.

I thought about a generic "Screen" class, which has functions like 
"add_element()" to insert a sprite or text into a layer on the screen.

Rendering is then done from the lowest layer to the highest one.
My question is now how I can implement these Layers, since I didnt find 
LikedLists or Hastables in Phobos.

My Idea in C++ would be to have a hashtable int to linked list, which 
gives me the linked list for a layer upon inserting the layer number, 
and the linked list then contains my ScreenObjects (a base class for 
images, text, buttons and so on).
What would be the best way to do this in D?