rollback method

bool rollback(
  1. int id
)

Takes one optimistic layer off the stack. Removal, not an inverse: it writes nothing to the store, so it is allowed for any layer.

Implementation

bool rollback(int id) {
  _ready();

  if (!_cache.takeOverlay(id)) return false;

  _record(ActionKind.rollback, 'overlay #$id');
  _cache.notifyChanged();

  return true;
}