}

    @Override
    public SortedMap<K, V> subMap(K fromKey, K toKey) {
      synchronized (mutex) {
        return sortedMap(delegate().subMap(fromKey, toKey), mutex);
      }
    }

    @Override
    public SortedMap<K, V> tailMap(K fromKey) {
      synchronized (mutex) {
        return sortedMap(delegate().tailMap(fromKey), mutex);
      }
    }

					continue
				}
				if _, f := res[fromKey]; !f {
					res[fromKey] = map[Reference]*Grants{}
				}
				if _, f := res[fromKey][toKey]; !f {
					res[fromKey][toKey] = &Grants{
						AllowedNames: sets.New[string](),
					}
				}
				if to.Name != nil {
					res[fromKey][toKey].AllowedNames.Insert(string(*to.Name))
				} else {
					res[fromKey][toKey].AllowAll = true
				}
			}
		}
	}