if (!swappy_array.observe()) return false; // failed to allocate.
for (int i = 0; i < len; i++) {
if (!detach(packed_form, swappy_array[i]))
if (!swappy_array.observe()) return false; // failed to allocate.
for (int i = 0; i < len; i++) {
if (!detach(packed_form, swappy_array[i]))