IConstructor top = TreeAdapter.getStartTop(tree);
String name = Modules.getName(top);
// create the current module if it does not exist yet
GlobalEnvironment heap = eval.getHeap();
ModuleEnvironment env = heap.getModule(name);
if(env == null){
env = new ModuleEnvironment(name, heap);
// do not add the module to the heap here.
}
env.setBootstrap(needBootstrapParser(data));