static double exclusive_measureSizeOfObject(int instances default 100000, IF0<O> f) {
  ret exclusive_measureSizeOfObject(instances, if0ToF0(f));
}

static double exclusive_measureSizeOfObject(int instances, F0<O> f) {
  O[] array = new O[instances];
  long mem1 = usedMemoryAfterGC();
  for i over array: {
    array[i] = callF(f);
  }
  long mem2 = usedMemoryAfterGC();
  ret (mem2-mem1)/(double) l(array);
}