if (s.isDoc())
return null;
Container parentContainer = s.getContainer();
TypeStoreUser parentUser = parentContainer.getType( getRoot() )._user;
if (s.isAttr())
return parentUser.get_attribute_field( s.getName() );
assert s.isBegin();
assert !parentContainer.isLeaf();
TypeStoreVisitor visitor = parentUser.new_visitor();
if (visitor == null)
return null;
for ( Splay t = parentContainer.nextSplay() ; ; t = t.nextSplay() )