static <A> A persistentObjectFromProgram(S progID, S name) {
  PersistentLister l = persistentListerReadOnly(progID);
  IVar<A> v = l.getVar(name, null);
  ret v == null ? null : v!;
}

// makeDefaultObject: (func -> A) or Class
static <A> A persistentObjectFromProgram(S progID, S name, O makeDefaultObject) {
  A a = persistentObjectFromProgram(progID, name);
  if (a == null)
    ret (A) (makeDefaultObject instanceof Class ? nu((Class) makeDefaultObject) : callF(makeDefaultObject));
  ret a;
}